14th Annual Meeting

Society of Nuclear Medicine

Papers To Be Read by Title

1. “TheEffect of Hyperbaric Oxygenation on the Uptake of Radioisotopes byTumors in Rats.―1NORMAN B. ACKERMAN, (Department of Surgery, BostonUniversity Medical Center, University Hospital, Boston, Massachusetts)

We have been interested in developing techniques for increasing radioisotope uptakeby tumors. During exposure of animals to OHP, oxygen tensions of tumors rise significantly.This condition occurs in parts of tumors which appear necrotic due to inadequate bloodsupply, as well as more viable tumors. It has not been fully determined how hyperbaricoxygen affects tumor metabolism and growth, nor how tumor vascularity is affected. Wehave attempted to study effects of OHP on uptake of radioisotopic agents with relation topossible changes in metabolism and vascularity.

Studies were performed on Sprague-Dawley rats with Novikoff hepatoma tumor implanted into the stomach wall. These tumors grow well in this location and can easily bedistinguished from surrounding normal stomach. Tumor vascularity was studied by administration of RISA and tumor metabolism by sodium phosphate (phosphorus-32). Experimentalanimals were exposed to 100% oxygen at 15 p.s.i.g. in a small animal hyperbaric chamber.At time of sacrifice, stomachs were studied by radioautography and by counting in anappropriately shielded well-scintillation counter.

Animals receiving 25 microcuries of RISA were sacrificed 24 hours later. Treatedanimals were continuously exposed to hyperbaric oxygen until sacrifice. Both control andhyperbaric animals had approximately a 40% increase of radioactivity in the tumors, althoughthe range was wide. In a preliminary group of rats sacrificed at four hours, neither controlnor hyperbaric animals concentrated more radioactivity than surrounding normal stomach.Experimental animals receiving 25 microcuries of phosphorus-32 were sacrificed after fourcontinuous hours of OHP. Both control and treated animals had increased 32p uptakes, butdifferences between the two groups were not significant. Further studies are in progress usingtumors in other locations. In addition, hyperbaric studies with 98% 02 and 2% CO2 are underway to determine whether CO2 can overcome any vasoconstrictive effects of pure oxygen.

‘Supported in part by the American Cancer Society, Massachusetts Division.

2. “SplenicTrapping of Heated-Erythrocytes in Leukemia and Allied Conditions.― HUSSEIN S. BAD1IAwI, MUHAMMAD A. RAzz@ic, AND BADIE Gumcls,(Department of Medicine and Division of Nuclear Medicine, Faculty ofMedicine, Cairo University, U.A.R.)

In a trial to find out whether or not the enlarged spleen plays a role in the productionof the form of anemia so commonly encountered in leukemias and allied conditions, 44patients suffering from these disease states were studied using 51Cr-tagged erythrocytesheated at 50° C for 60 minutes. Cells altered in this manner have been shown by variousworkers to be selectively sequestered by the spleen.

As a control, the test was performed on 24 normal subjects. In these normals, thedisappearance half-time of radioactivity from the circulation (T3@) amounted to 172 ± 69minutes (Mean ±1 S.D.), the range being 74 to 280 minutes. Accordingly, patients with

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380 ABSTRACTS

T3@less than 74 minutes were considered to have an abnormally rapid disappearance of heattreated erythrocytes from the circulation and, consequently, exaggerated splenic sequestrationof these altered cells.

Splenic trapping of heated-erythrocytes was most marked in acute leukemia ( 4 out of6 cases ) . However, three had associated normoblastic hypoplasia of the sternal marrow.Corticosteroids induced a remission with reversion of both processes responsible for theanemia in two out of these four patients.

In chronic myeloid leukemia, exaggerated splenic sequestration of altered cells was seenin four of the iS cases examined. This condition was of extra-erythrocytic origin, sincerepetition of the test using normal donor heated-erythrocytes did not significantly alter thedisappearance half-time. However, there was no correlation between the size of the spleenand its avidity for trapping altered cells. Follow-up studies showed that therapy causedprolongation in Th of heat-treated erythrocytes, the effect being more apparent aftercorticosteroids than with x-rays or endoxan.

In Hodgkin's disease, increased red cell trapping was observed in two out of the sevenpatients studied.

In contrast, five cases of chronic lymphatic leukemia, six lymphosarcoma, and fivereticulum cell sarcoma had normal disappearance half-time of heated-erythrocytes from thecirculation.

3. “Variation of Scan Pattern in Middle Cerebral Artery Occlusion.― H@o H.BYUN, MARION F. MAGALOTrI, Fa@t@c STASIA, ANTHONY J. R@tn@@soNDI, @i

DAVID YASHON, (Cook County Hospital, Chicago, Illinois)

Some of the interesting abnormal brain scans other than neoplasm are those producedby acute cerebro-vascular occlusion. There appears to be more than one pattern of abnormalbrain scan finding in acute cerebro-vascular accident and good reasons exist for not expectinga single scan pattern in occlusion of the middle cerebral artery.

It has long been known in the fields of neuropathology and neurosurgery that occlusion of a main intracerebral artery does not produce a consistant pathological picture ofinfarction involving the entire area normally supplied by that vessel. Various sizes anddifferent patterns of infarction depends chiefly upon the size of the affected area and thedegree and availability of collateral circulation to the involved area. It is also important thatthe blood pressure at the time of occlusion be high enough to open these channels.

Zulch has concisely diagrammed the various types of infarct patterns seen in the middlecerebral artery occlusion. These patterns range from the large wedge shaped infarcts involving the entire area by the middle cerebral artery to small linear areas in minimalinfarction. It would therefore follow as a reasonable conclusion that since the pathologicalpattern in middle cerebral artery occlusion may vary, the scan pattern may also vary.

In evaluating the abnormal scans of infarction, one must consider that the pattern mayvary not only because of the presence or lack of collateral circulation, but also because offactors such as surrounding brain edema in the acute stage of infarction, which maysimilarly disturb the blood brain barrier.

We found a wide variety of scan configurations in our abnormal brain scans in acutecerebro-vascular accident, which we attempted to classify as follows:

1. Tubular

2. Triangular3. Wedge shaped

4. Bi-lobular5. Tumor-like6. Diffuse

Examples will be presented.

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4. “Selenium-75: What is the True Activity?― PATRICIA A. CLIGGETT, (Radia

tion Safety Section, National Institutes of Health, Bethesda, Maryland)

The National Institutes of Health has recently begun using selenium-75. Assays of thefirst shipments showed a considerable discrepancy between the values given by the supplierand those obtained at the National Institutes of Health. In order to determine the accurateassay of the material, the decay scheme of the radionuclide was examined and a search wasconducted for an appropriate standard. A comparison was made of the assays of this nuclideon shipments from several suppliers and the Oak Ridge National Laboratory cooperated inmaking this a three-way intercomparison study. The results of this study are presented witha suggestion for uniform use of the most recent data on the decay scheme of selenium-75.

5. “TheSynthesis of Carbon-14 and Radioiodinated Compounds in the Dichlorodiphenyldichloroethane (DDD) Series.―' R. E. COUNSELL, R. E. WILLETrE, AND W. DlGunio, (College of Pharmacy and Department of In

ternal Medicine, University of Michigan, Ann Arbor, Michigan)

As part of a broad program aimed at the development of a radiopharmaceutical foradrenal photoscanning, we have synthesized a number of carbon-14 and iodine-125 labeledDDD isomers and analogues. Our selection of DDD and related compounds for this studywas based on the reported predilection of these substances for adrenal tissue.

Our initial studies involved the synthesis of carbon-14 labeled o,p'-, m,p'-, and p,p'-DDD,used to obtain information regarding the tissue distribution, excretion, and metabolism forcompounds in this series. These compounds were synthesized by acid catalyzed condensationof chlorobenzene-14C with an excess of the appropriate 2,2-dichloro-i-( chlorophenyl)-ethanol.Because of the problem of isomer by-products in these syntheses, it was absolutely essentialthat the purity of each compound be firmly established. Gas liquid chromatography ( GLC)was found to be the most effective tool for assessment of purity. In addition, the NMRspectrum for o,p'-DDD was readily distinguishable from those for m,p'- and o,p'-DDD.

Iodine-125 was selected for the synthesis of the radioiodinated analogues, since its longhalf-life and low radiation energy simplified the synthesis and storage of the products. Toobtain the isomeric o, m, and p-chlorophenyl-p'-iodophenyldichlorethanes, iodobenzene wascondensed with the appropriate 2,2-dichloro-1-( chlorophenyl)ethanol in a manner similar tothat described above. The introduction of 125! was readily effected by exchange with iodide125 in ethylene glycol at 180°.The radiolabeled componds were purified by recrystallizationand analyzed by thin layer chromatography.

Preliminary tissue distribution studies on the three radioiodinated products have beencarried out in rats at 4 and 24 hours following I.V. administration. All three compoundsshowed a similar tissue distribution pattern. At four hours, fat, adrenal, and liver concentrations were significantly greater than all other tissues studied. At 24 hours, the radioactivityin all the tissues except fat had fallen. Additional studies are in progress.

iThis work was supported by grants from the American Cancer Society, National Institutes of Health, and H. H. Rackham School of Graduate Studies of the University ofMichigan.

6. “TheRatio of Protein-Bound Iodine to the in vitro Binding of Triiodothyronine by Serum Proteins as an Index of Free Throxine Concentration inSerum.―ALFREDo CUARON, (Hospital General del Centro Medico Nacionaland Comisión Nacional de Energia Nuclear, Mexico City, Mexico)

Thyroid function was studied in S60 subjects (109 hyperthyroid, 106 hypothyroid, 146pregnant women, 19 nephrotic patients and in 180 normal subjects), all of whom werestudied by thyroid uptake of P31, conversion ratio, protein-bound iodine concentration in

382 ABSTRACTS

serum ( PBI ), in vitro binding of triiodothyronine (T3 ) by serum proteins, and total andfree thyroxine binding globulin (TBG) capacities.

The plotting of values of PB! against the percentage of binding of T3 by serum proteinsallowed the separation of the five groups studied. The amount of PB! was found to increasein hyperthyroidism and during pregnancy and to decrease in hypothyroidism and nephrosis.The binding of T3 to serum proteins was elevated in hypothyroidism and during pregnancyand lowered in hyperthyroidism and nephrosis.

The index obtained dividing the PB! concentration by the in vitro binding of T3 byserum proteins similar to that of Clark and Horn was found to be increased in hyperthyroidism and decreased in hypothyroidism, but during pregnancy and in nephrosis its valueremained normal.

Total and free TBG capacities, PB! concentration and binding of T3 by serum proteinsincreased from the twelfth week of pregnancy to labor and decreased to normality during thepost-partum period.

The index represented by PB! concentration to binding of T3 by serum proteins remainednormal throughout the pregnancy and post-partum.

The PBI concentration, the binding of T3 by serum proteins, the dializable fraction ofthyroxine ( Df-T4 ) and the molar concentration of free thyroxine (FT4 ) were determinedin 45 subjects.

The index, the dializable fraction of T4 and the free thyroxine concentration were foundincreased in hyperthyroidism and decreased in hypothyroidism. Both for pregnancy andnephrosis, the values of the index, the dializable fraction of T and the Free T4 concentrationwere normal, but the PB! concentration was found increase@l in the former and decreasedin the latter. The index and the free T4 concentration were found to be in a highly significantpositive correlation.

It is postulated that the simultaneous estimation of PBI concentration and of in vitrobinding of T3 by serum proteins increases the diagnostic accuracy mainly in those cases inwhich it is expected to find atypical variations on TBG capacities, such as in nephrosis andin pregnancy.

The empirical index described here is positively correlated with the molar concentrationof free T4 in serum and its estimation can be considered as a simple and practical procedureto obtain a value proportionaly related to the actual concentration of free T4 during thedaily routine.

7. “ADose Check Meter for Radiopharmaceuticals in the Diagnostic Clinic.―JACK D. DAVIDSON, AND WILLIAM L. Asmn.mIN, (Nuclear Medicine Department, National Institute of Health, Bethesda, Maryland)

The physician who administers doses of radiopharmaceuticals should have a simplemethod of verifying the radioassay and identity of the material he is about to inject, entirelyindependent of his supporting personnel. This can be done with a simple device using anysort of ratemeter, a Geiger-Mueller detector and a calibrated range. The range consists of aboard two inches wide, arranged to hold the dose syringe transversely at calibrated fixeddistances from the G-M tube. A Mo inch aluminum absorber is mounted in front of thedetector to eliminate variability contributed by beta praticles of 131! and gold-198. Shallowtransverse notches are located down the range board for each radionuclide as determinedwith known doses of the radionuclides, so that the meter reads 1000 cpm per 100 @zCforeach radionuclide in its respective notch. Using an old Nuclear Instrument and ChemicalCorporation Model 1615-B ratemeter with an unshielded D-34 detector tube, 85Sr, 9amTc,

@ ‘97Hg and ‘98Au calibration notches fell between 4 and 8 inches from the detector.

The accuracy is within 15% despite variation in dose volume from 0.5 ml to 6 ml and useof 2, 5 or 10 ml plastic syringes. All measurements are made with the column of fluid in thesyringe centered on a longitudinal midline on the range board. The shallow range slotsautomatically center the dose for distance from the detector, irrespective of syringe diameter.

FOURTEENTH ANNUAL MEETING 383

A presumptive confirmation of the radionuclide identity is made by using appropriatehalf-value layer absorbers, e.g., %2―lead for 85Sr, 1―aluminum for DOmTc,14j―aluminum for197Hg, and @“lead for iodine-131. Gold-198-colloid depends on its color to differentiate itfrom 131! compounds. We similarly rely on blue dye incorporated in our 9OmTc@sulfidecolloid to distinguish it from pertechnetate.

8. “TheMercury-197 Chiormerodrin Brain Scan in Patients with Cerebral In

farction.― WALTER DIGwuo, AND E@uu. R. FERINGA, ( Radioisotope and

Neurology Sercies, Veterans Administration Hospital, and Departments ofInternal Medicine, Nuclear Medicine, and Neurology, University of Michigan Medical School, Ann Arbor, Michigan)

Since January 1965, l9THg Chlormerodrin brain scans were performed on every patientadmitted to the Ann Arbor Veterans Administration Hospital with a clinical diagnosis ofcerebral infarction. Initially, only positive scans were repeated. More recently, to enlargethe number of unbiased scans at variable post infarction intervals, repeat scans have beenobtained routinely. These and all initial scans are referred to as “unselected―scans. Seventytwo patient records are analyzed in this report.

There were 27 positive and 31 negative unselected scans during the first six weeks.Only 3 of 19 unselected scans were positive more than six weeks post infarction. The highestpercentage of positive scans was observed at three weeks.

The EEC performed within a few days of the scan was often positive when the scanwas negative. There were 58 positive EEGs and 28 positive scans in 72 paired studies. Onlyone negative EEC was obtained when the scan was positive.

Patients were divided into four classes according to disability. The scan was positivemore than four weeks after infarction in one patient of 22 with minor disability. The scanwas positive beyond four weeks in 19 of 37 patients in the two higher classes of disability.Seven of 20 patients who had positive scans beyond 28 days were dead at followup evaluation.Only 5 were dead of 39 patients with negative scans beyond 28 days.

Fifty-one of 72 patients were alive at the last followup period. Only 26 of the surviving51 patients had positive first scans, whereas 16 of the 21 decreased patients had positivefirst scans. These findings suggest a prognostic value of the brain scan in patients with cerebralinfarction.

9. “Pertechnetate Scanning of the Thyroid with Low Iodide Uptake.― W. J.DODDS, AND M. R. POWELL, (Nuclear Medicine Section, Department ofRadiology, University of California School of Medicine, San Francisco,California)

Either because of disease or suppression by exogenous agents, the thyroid with lowradioiodide uptake, retains some of its capacity to trap monovalent anions. The ratio oftarget counts in this trap to non-target counts in surrounding neck tissues is low, but excellentquality thyroid scans may be made by labelling the thyroid trap with sufficient counts andby using appropriate background suppression during scanning. Mihicurie amounts of technetium-99m pertechnetate may be used in thyroid scanning with favorable dosimetry, compared to conventional 1131 scanning doses. Pertechnetate thyroid scans have provided thefollowing improvements in scanning technique:

1. Better resolution of contours of cold areas within thyroid images;2. Imaging of glands with marked suppression of 1131 uptake either because of pituitary

insufficiency or medication, including exogenous thyroid therapy, thiouracils, iodides, andother suppressive agents;

3. Improved visualization of glands affected by primary thyroid diseases;4. Reduction of thyroid radiation dose, making use of this agent particularly desirable

in the pediatric age group.

384 ABSTRACTS

10. “RadioisotopeTechniques in the Assessment of Hepatic Radiation Injury inthe Rat.―PAUL A. F@uuu@ii,u'm Pinui' RUBIN, (Division of Radiation Therapy and Radioisotopes, Department of Radiology, University of RochesterSchool of Medicine and Dentistry, Rochester, New York)

Based on recent observations, it is becoming apparent that the liver is a more radiosensitive organ and subject to damage following external irradiation than had been generallythought. Clinical and histological features of radiation hepatitis developing after therapeuticirradiation of the liver have already been described ( Ingold et al, Am. 1. Roentgen. 93:200-208, 1965 ) . However, the precise mechanism and the interrelated roles of the vasculature,reticuloendothelial cell-compartment and parenchyma in radiation injury to the liver arenot fully understood. A number of currently available radiopharmaceuticals permit in vivoscanning of the liver on the basis of selective distribution and localization in one or otherhepatic tissue-compartment. Radiocolloids (e.g., Au-198) provide a means of visualizing thereticulo-endothelial ( Kupffer) cell-compartment and of quantifying phagocytic function. Inaddition, colloidal Au-198 can be used for the indirect determination of effective liver bloodflow. Hepatic scintiscans using 1-131 Rose-Bengal or carrier-free Mo-99-molybdenate provide a visual outline of the polygonal cell- compartment and with Rose-Bengal it is possibleto evaluate parenchymal function and biliary patency. Lastly, the hepatic vascular “bed―can be visualized by scanning with 1-131 serum albumin which outlines the intrahepaticplasma “pool―.

In experiments using Sprague-Dawley male rats, the above radioisotope techniqueswere applied in order to observe and identify possible specific changes in the different tissuecomponents of the x-irradiated rat-liver. The study was also designed to evaluate the use ofin vivo radioistope procedures in detecting hepatic radiation injury and assessing the severityand duration of damage. In the first phase of the study, single dose schedules of 1000, 2000,3000, 4000 and 5000 rads partial hepatic x-irradiation were used. In addition, groups of ratsreceived x-irradiation to the entire liver in the same single doses. The second phase is designed to use fractionated doses at the rate of 200 rads per day, to total accumulated dosesof 3000, 4000, 5000, and 6000 rads. The results will be reported in some detail and ourtentative impressions concerning the pathophysiologic effects of localized hepatic irradiationwill be outlined for discussion.

11. “ClinicalExperience with a Ten Detector, Digital Rectilinear Scanner.―ALBERT J. GILSON, (Division of Nuclear Medicine, University of Miami

School of Medicine, Miami, Florida)

The instrument consists of ten adjacent crystals measuring 2―X 6―X 7k―with a backing ofindividual photomultiplier tubes, amplifiers, spectrometers and digital counting circuits. Eachof the ten assemblies is capable of independent counting and data recording. The ten detectorhead moves at speeds up to 240 cm/min. On each pass, ten lines of scan information arerecorded on magnetic tape and C.R.T. display.

Five hundred patients have had clinical examinations with this instrument. The initial100 were performed in conjunction with scans from a conventional 5―Picker Magnascanner.

12. “ClinicalUse of the Vertex View in Brain Scanning.―THOMASGUYTON,ANDALBERT J. GILSON, (Department of Radiology, Division of Nuclear Medi

cine, University of Miami School of Medicine, Miami, Florida)

In an attempt to improve the diagnostic accuracy of our brain scanning procedure,we have obtained a vertex view whenever the interpretation of the conventional views is indoubt or when more definitive spatial localization might be of benefit to the surgeon or radiotherapist. The vertex view was first described by Overton (I. Nuc. Med., 6:705, 1965) andits anatomical landmarks were well defined by Mack (I. Nuc. Med., 7:633, 1966). We

FOURTEENTH ANNUAL MEETING 385

have confirmed the former's finding that the vertex view may be the only view to demonstrate a cranial lesion. In addition, we have found that the vertex view occasionally offersa better opportunity to detect discrete metastatic lesions than the conventional views.

In our series of about 1,000 brain scans, we have obtained 100 vertex views in additionto the conventional views. Our series includes pre-operative primary brain tumors, e.g.,

@ astrocytomas, meningiomas, as well as metastatic brain tumors from breast, lung, esophagus,kidney, etc.

In our laboratory routinely after the intravenous injection of 5 mCi of 99mTc, two ormore conventional views are obtained. Each view takes approximately ten minutes with the5―Magnascanner® or approximately eight minutes with the Dynapix® unit. The decisionto obtain a vertex view is based on the results of the conventional views and the patient'sclinical history reviewed before all injections.

A disadvantage of the available scanning units is the inability to obtain the vertexview on the unconscious patient or on the patient who is suffering from an incapacitatinghead lesion or other illness.

We have found with the use of our headrest chair that the leaded rubber apron toshield the shoulders is not uncomfortable for the short period of time necessary.

We believe that in certain selected cases this vertex view is a rewarding adjunct to thediagnostic brain scanning procedure.

13. “RadioactiveIron (59Fe) Excretion Through the Urine and Feces After Intravenous Iron-59 Administration in Congenital Hemolytic Anemias.― H. GYFTAXI, M. KESSE-ELIAS, M. CONSTANTOULAKIS, AND B. MALAMOS, (Depart.

ment of Clinical Therapeutics, University of Athens and the RadioisotopeLaboratory, “Alexandra―Hospital, Athens, Greece)

In the present study, determination of the percentage of radioiron ( 59Fe ) excretion infeces and urine has been made, after i.v.59Fe administration, in thalassemic patients, sicklecell anemia patients and carriers of thalassemic trait.

The maximum excretion of 59Fe in urine has been found to occur during the first 24hours ( it ranges between 0.077 and 0.127% for thalassemic patients with about equivalentvalues for the thalassemic traits and sickle-cell anemia cases), while in the following daysthe excretion falls to much lower values forming a plateau. In one thalassemic patient withhemochromatosis the percentage of the first day excretion was much higher (1.64%).

The fecal excretion remained lower than the first day urine excretion and continuedduring the study (6-10 days), forming either a plateau or showing small peaks. The abovefindings are compared with the scanty reports in the literature on patients with hemolyticanemias, aplastic anemias and normal subjects.

Comparison is made to normal persons and thalassemic patients after desferrioxamineadministration.

14. “Stereoscopicand Fluorescent Electron Microscopy.― T. L. HAYES, R. F. W.PEASE, L. W. MCDONALD, AND A. S. CAMP, (Donner Laboratory, Lawrence

Radiation Laboratory, and Department of Electrical Engineering, University of California, Berkeley, California)

Electron bombardment can cause a specimen to emit secondary electrons, visible light,characteristic x-rays and backscattered electrons. Each of these radiations contains informationof a particular type relating to the specimen. If we scan a tiny electron beam over thespecimen and scan, in synchrony, a second beam of electrons over the screen of a cathoderay tube, we have established a one-to-one correspondence between points on the specimenand points on the cathode ray tube. If the brightness of the spot on the cathode ray tube atany instant is determined by the signal from a detector measuring the intensity of one ofthe secondary radiations coming from the specimen, an image can be built up on the face ofthe cathode ray. Such a device, called a scanning electron microscope, greatly increases the

386 ABSTRACTS

kinds of information available from electron microscopy. The instrument may also be used as amicro-irradiation source capable of delivering high dose rates ( lOTrad/sec ) electron radiationto a very small ( 10—6cm2) area. At the same time, the scanning electron microscope allowspositioning of its beam with great precision.

In the scanning electron microscope the picture is built up by a point-by-point timesequence; hence, the information used to build up the picture need not be focused in anoptical sense. The information content of the picture is greatly expanded by the use ofemitted radiation not available to the ordinary electron microscope. The dimension addedmay be stereoscopic, molecular, or chemical, depending on the kind of radiation used.Human cells and tissues have been examined stereoscopically at magnifications up to 10,000times and living organisms have undergone micro-irradiation and visualization using thescanning electron microscope technique.

15. “ScintiphotoLiver Scans.―GEORGEC. HENEGAR,VERNONWAiw, AND BARBARAFRITSCH, ( Veterans Administration, Research Hospital and Department ofSurgery, Northwestern University Medical School, Chicago, Illinois)

The development of the scintiphoto technique for organ visualization has led to amethod which delineates space-occupying lesions better than heretofore available and hasalso led to a means of evaluating for portal hypertension in the cirrhotic.

Collodial 98Au or 99mTc sulfur colloid is used as the label. The scans are made with ascintiphoto camera by the breath holding technique described by Gottschalk.

Two hundred fifty-four scans of the liver were performed at Veterans AdministrationResearch Hospital by this method. Resolution was excellent and there was good definitionof the liver edge as compared to scans made while the patient breathed normally. Spaceoccupying lesions, such as primary and metastatic carcinoma, were well delineated by thismethod.

In cirrhotics with hepatic insufficiency and portal hypertension, the liver was faintlyshown; the spleen concentrated most of the label and marked portal hypertension existed.The bone marrow in the vertebral bodies showed a high uptake.

16. “TheLabeled Phosphate (Na2HP32O,) As Fixed in vivo in Tissues Seriouslyinjured Morphologically.― T. S. HOLAN, L. CAPUSAN, M. MICLUTEA, P.POCANGEUNU, ( Clinical Radioisotope Unit and Dermatological Hospital,The Medico-Pharmaceutical Institute, Cluj, Romania)

It is generally accepted that the nucleic acids are of utmost importance in cellularmultiplication and division and that protein synthesis is one of their main functions. Thatis why for our experiments we have chosen phosphorus as the fittest radioactive isotope;it is easily followed in vivo and it is a component of the proteins as well.

Phosphorus is to be found together with a pentose and a nitrogenous grouping, asphosphoric acid in the structures of nuclear proteins. They all are mononucleotids which intheir turn may change into nucleic acids. Phosphorus takes part in the glucose metabolism,to9 (the hexaphosphoric esters are the source of macroenergy); as well as in lipid metabolism(as phospholipids) and it is important in bioenergetic cellular functions.

We have studied labeled phosphate dynamics and differences of their uptake incancerous and benign tumours, in inflammatory and degenerating tissues, in hyper- orparakeratoses, in atrophic cutaneous disorders, on prepared tissues of patients who havehad collagenous disease, and in irradiated (x-rays) skin surfaces.

As a first finding, an increased essential need of phosphates in all these biological derangements occurs, and this finding may be demonstrated by an increased in vivo uptakeof the radiophosphates in injured tissues, save for some degenerating processes (like fibrocystic mastopathy for instance) or atrophying processes when the intake of phosphates islower than in normal tissues.

FOURTEENTH ANNUAL MEETING 387

The dynamics of increased uptake are different according to the derangement: i.e. theparakeratotic process ( psoriases ) starts with an initial uptake, a plateau follows in a fewminutes, and the highest uptake is reached within 24 hours. In malignant tumours after acontinuous rise, a plateau or a slightly ascending line next occurs.

Our interpretation : the different metabolic derangements are likely to cause variousdynamic aspects of the fixed phosphorus and we can utilize this fact in differential diagnosticproblems.

17. “TheUptake and Concentration of the Pertechnetate ion by the ChoroidPlexus.―DAVID W Jtsi@ui, ROBERT J. Giim, AND WIL B. NELP, (Division ofNuclear M@dicii@Uiii@sity of Washington School of Medicine, Seattle,Washington)

Concentrations of radioactivity in the region of the choroid plexus are noted in aboutfive per cent of otherwise normal brain scans done with pertechnetate ( OamTcO4-@@) . Thislocalization of activity may be eliminated if the patient is pre-treated with perchiorate.Because of these observations, the metabolic relationship of the rabbit choroid plexus to thepertechnetate ion was studied in vivo and in vitro. One hour after the intravenous injectionof 99mTcO4_ ( 200 uc/Kg. body weight), the concentration of activity in the choroid plexusaveraged 1.4 times greater than plasma. All other tissues except thyroid had concentrationsless than that in plasma (brain .03, muscle .15, cerebral spinal fluid .01, thyroid 50). Whenrabbits received 20 mgm/Kg. of potassium perchlorate 30 minutes prior to O9mTcO4_ thechoroid plexus to plasma concentration ratio was reduced to 0.6, while other tissue concentrations except thyroid were unaffected. Fresh choroid plexus progressively concentratedpertechnetate when incubated at 37°in Tyrode's solution containing 1 uc/ml of 9OmTcO4_.After one hour the choroid plexus attained 40 times the activity of the surrounding incubationfluid. The choroid plexuses of animals pre-treated with perchlorate showed a significantreduction of in vitro uptake of pertechnetate, ( concentrations of 10 times that in the incubation fluid). These studies support the concept that the pertechnetate ion is actively concentrated by the choroid plexus and that this process can be blocked by perchlorate.

18. “PlacentalScanning with Technetium-99m-Labeled Albumin.―P M Johnson,J. J. Sci&im@,@r'wJ. A.O'LEARY,(ColumbiaUniversityCollegeoUPh@1.cians and Surgeons, New York, N. Y.)

High resolution scintillation scanning of the placental blood pool was performed in 36gravid patients using technetium-99m bound to human serum albumin. The anatomic siteof the placenta was subsequently determined in each patient by manual removal at time ofdelivery. The placental site was correctly predicted by the scanning technique in 34 patients,including 6 of 7 patients with placenta previa. Less than 5% of the radionucide underwenttransplacental passage, as determined by measurement of radioactivity in maternal and cordblood in 10 patients who received the tracer zero to 4 hours before delivery. Placental scanningappears preferable to older methods of placental localization.

19. “RadioisotopeScanning of Pancreas Carcinoma.― HIROTAKEKAKEm, YUKIOTATENO, Gino UCHIYAMA, ANI) ShIN TSUCHIYA, (Department of Radiology,

Chiba University School of Medicine, Chiba, Japan)

Since 1962, the usefulness of radioisotope scanning with Se-75-selenomethionine for thediagnosis of pancreatic diseases has been investigated in our department. Se-75-selenomethionine is intravenously administered without any dietary preparations or premedications.The scan is started 5 to 10 minutes after the administration of the isotope. Immediately afterthe first scan including the entire liver and the pancreas is through, the second scan of thepancreas in limited area is taken with half-overlapped lines. The second scan allows clear

388 ABSTRACTS

visualization of the outline of the pancreas. Visualization of the pancreas was obtained inmore than 95% of the cases. The scans of the normal pancreas are classified into two typesby the scanned form of the body and tail of pancreas. One is the so-called “reverse5―type,which is straight or curved shape. In this type, the incisure of pancreas is almost alwaysclearly seen. The other is the “horseshoe―type, which shows a concave and the incisure isnot so clear as the former one. Chronic pancreatitis shows no remarkable changes.

Pancreas carcinoma shows six suspected findings as follows:

1. Circumscribed defect in pancreatic shadow.

2. Complete defect of a part of pancreas.3. Unclear delineation of pancreas.

4. Irregularity of pancreas contour.

5. Narrowing of pancreas shadow.6. Defects in the liver shadow.

The percentage of appearance in circumscribed defect is 31%, complete defect of a partof pancreas, 23%, unclear delineation, 23%, irregularity of the contour, 12%, and narrowing,8%. Three per cent had no obvious findings. The smallest carcinoma correctly interpreted bythe pancreas scan was 3 cm in diameter in the head and 2 cm in the tail.

20. “SomeStudies of Absorptiometry in Two Component Systems Using IsotopicX-ray Sources.― DAVID M Li@uw, Lirrium E. PREUSS, AND C@&in@mSK.BUGENIS, (Department oUPhyii@Edsel B. Ford Institute for Medical Research, Detroit, Michigan)

The potential life science application of the two-photon absorption system has stimulated this laboratory to a preliminary evaluation, using x-rays from 1251 and Americium-241.The physical principle and theory are well-established. Where the mass absorption coefficients and the differential absorption for two monochromatic photons are known, the cornponent concentration computation is straightforward. Ratio determinations done here andelsewhere on known, synthetic systems showed that the method was sensitive to experimentalparameters and this fact raised questions as to the inherent accuracy and reproducibility ofthe system. The present phase of this investigation consists of an in-depth examination ofthese various parameters and their effect on the methods' reliability.

It was early determined that this critique of the methodology would require spectroscopyof these low-energy photons. To this end, a laboratory system, scintillation detectors, anda 128-channel analyzer with attendant linear pulse amplification and readout were employed.Two approaches were made in the experimental design. In the first, a standard plot wastheoretically established, using published values for the component mass absorption coefficients. In the second case, experimental values from internal standards were used to plot anexperimental calibration curve.

This phase of this critique, carried out with non-biological (but organic) two-componentsystems, proved that the methodology was highly reactive (error-wise) to a number ofelements. Among these were the overall geometry, sample configuration and thickness, scattering distance, aperturing, filtering, and selection of the spectral section. Where thesefactors were not optimized, large errors resulted.

Determinations made under best experimental conditions show a straight line plot, aspredicted, parallel to but not coincident with the theoretical plot and displaced by abouttwo per cent at mid-point. Experimental plots fall within one per cent of a straight line. Thisfinding indicates that an experimental internal standard is the calibration of choice and thatthe methodology holds promise when carefully controlled.

21. “SomeClinical Aspects of Computer-Processed Scintiscans.― LESTERM LEVY,(Division of Nuclear Medicine, Long Island Jewish Hospital@NH@l@

FOURTEENTH ANNUAL MEETING 389

Park, New York and Department of Radiology, Downstate Medical Center,Brooklyn, N. Y.)

With full-time availability of a small 8K word DDP-116 computer, it has become possible to link a conventional 5-inch scintiscanner to produce computer-processed scintiscans.

Full storage of the original digital data recorded as small elements along each scan linepermits rather complete control over the output. No longer subject to fortuitous positioningof the controls on the scanner, the computer affords complete control over contrast. It ispossible to divide the full dynamic range of count rates into as many levels as desired, eachdisplayed with a discrete symbol. Moreover, the program permits variable widths of eachlevel, so that curves of contrast may be linear with count rate or vary as some curvilinearfunction. An iterative smoothing process may also be applied to decrease irregularities dueto statistical fluctuations analogous to optical data blending, but with more control.

The response of the smoothing process will be demonstrated in clinical scans to illustratethe power of this method. Several clinical scans processed by the digital computed will bepresented to illustrate the increased diagnostic possibilities.

Future plans in terms of computer control of the scanner, of immediacy of display, andof possible future improvement in resolution will also be discussed.

22. “Evaluationof Rectilinear Scanners and Scintillation Camera for Scintiphotography.― Muu@ K LOKEN, (Nuclear Medicine Clinic, University ofMinnesota hospitals, Minneapolis, Minnesota)

Following the installation of our scintillation camera early in 1965, we have beenevaluating this unit and conventional rectilinear scanners as scintiphotographic devices. Thisevaluation has been a continuous process because of a series of improvements being made tothese instruments, particularly in collimators. Studies to date have included use of a phantomskull ( Picker Nuclear ), a phantom liver developed in our laboratories several years ago,and a rectangular phantom of recent design containing pseudotumors of various sizes, whichhave either a greater or lesser concentration of radioactivity than the remainder of thesystem.

Several studies have been performed using our scanners and camera according to accepted standards for operation of these units in our clinic. These studies have shown comparable results in the resolution of pseudotumors in the brain and liver phantom. The timeallotted for obtaining the various scintiphotograms for these studies was not fixed. Thus, astudy was recently initiated to evaluate these scintiphotographic devices with the sameamount of time allotted for obtaining each scintiphotogram. This study has permitted amore precise evaluation to be made of our techniques for operating each of the scannersand the camera than was possible before.

The radioisotope of principle interest for these phantom studies has been 99mTc,although consideration is also being given to the use of 19THg, 131! and gold-198.

23. “LiverScans and Brain Scans as Screening Procedures in Bronchogenic Carcinoma.― K@r@m R McCorni@i1tac, ROBERT H. GRB@it@tw, AND CLrwris R.HOPKINS, (Department of Radiology, University of Kentucky Medical Cen

ter, Lexington, Kentucky)

Metastases from bronchogenic carcinoma can be very widespread, and two of the morecommon distant sites of metastatic spread are the liver and the brain. Extensive therapeuticprograms (surgery, radiation therapy and chemotherapy) are being utilized with increasingfrequency to control bronchogenic carcinoma. Knowledge of distant metastatic spread at thetime of the initial evaluation of patients with bronchogenic carcinoma would definitelyinfluence the choice of therapeutic endeavors. Scintiscanning of the liver and brain could beof real benefit as a screening procedure to rule out major metastatic spread, if a sufficientnumber of occult metastatic lesions can be demonstrated by these techniques.

390 ABSTRACTS

Liver and brain scans have been performed on a series of patients with proven diagnoses of bronchogenic carcinoma. The findings on the scans will be presented, with correlation as to presence of clinical findings referable to these organ systems and available confirmatory evidence from surgery or post-mortem examinations as to presence or absence ofdistant metastases to liver and/or brain. The prospective usefulness of these procedures willbe evaluated as screening techniques in patients with bronchogenic carcinoma.

24. “Significanceof Splenic Concentration of Radioactive Gold in Liver Scans.―MARION F MAGALOrrI, HY0 H. B'@uN, RAYMOND J. DES ROSIERS, F@iu'@A@@rnoVIu@, FREDERICKS@iCMANN, AND ILTIFAT A. Ai@tv@, (Cook County Hospi.tal, Chicago, illinois)

In performing scanograms of the liver with radioactive colloidal gold, one often encounters a significant concentration in the spleen. It is generally accepted that a normal spleenmay concentrate radioactive colloidal gold approximately 10% of that seen in the liver. Infact, however, in most normal liver scans, the spleen is barely visible. Concentrations of morethan 10% are felt to be abnormal, but the exact significance of this finding has not beendefinitely established. In an attempt to help clarify this point, we reviewed 633 liver scanssince January 1965 through July 1966 and found 103 cases which showed more than atrace concentration of radioactive colloidal gold in the spleen.

The scans are classified according to splenic concentration:+ 1 Splenic concentration : Concentrates less than the liver ( 43 cases)2+ Splenic concentration : Concentrates equal to the liver ( 33 cases)3+ Splenic concentration : Concentrates more than the liver ( 20 cases)4+ Splenic concentration: Concentratesalmost exclusively (7 cases)

These 103 cases were reviewed by gastroenterologists and all available data was tabulated.None of all the liver profile examination showed any significant correlation with the degreeof splenic concentration, but liver biopsy, laparoscopy and clinical diagnosis supported bythe liver profile showed a significant trend.

Cirrhosis of the liver was by far the most common diagnosis. However, fatty liver,hepatitis, tumor, T.B., sarcoid and fibrosis secondary to congestive heart failure and cholestasis, due to common duct stone, also showed significant concentrations.

25. “Strontium-85 Bone Scans as an Aid in the Selection of Patients for Phosphorus-32 Therapy of Skeletal Metastasis.― Wn..UAM S MAxlrmLD, ANDJom4 D. WATSON, JR., (Oschsner Clinic, New Orleans, iiii@i@i)@

Extensive skeletal metastasis from carcinoma of the breast and carcinoma of the prostatecan be treated by therapeutic doses of phosphorus-32. The selection of patients for this formof treatment has been difficult, as there may be severe depression of the hematopoietic systemif there is not an excellent differential of 32p localization in the areas of metastatic disease.Since 85Sr and 32p follow similar metabolic pathways depositing in areas of new boneformation, the bone scan has been employed as a test to aid in the selection of patientsfor 32p therapy. When the bone scan shows 85Sr localization in all areas of known diseaseand the degree of localization as demonstrated by spot counting is good, the patients haveresponded well to the 32p therapy. When poor localization of Strontium occurs, phosphorustherapy has not provided palliation.

26. “BrainScanning in the Pediatric Age Group.―C DOUGLASMAmItiw, (Bowman Gray School of Medicine, Winston-Salem, North Carolina)

Between January 1964 and January 1967, brain scans employing 99mTc pertechnetate wereperformed on 130 children at the North Carolina Baptist Hospital. In this group, thirtyeight positive brain scans were obtained.

FOURTEENTh ANNUAL MEETING 391

A conventional three-inch scanner and a 19-hole low energy collimator were used. Following the administration of two to ten millicuries of 99mTc pertechnetate, counts in the rangeof 10,000 to 20,000 were obtained and scanning was begun immediately. Four or five viewswere routinely obtained, requiring approximately one hour.

There were twenty-five proven primary brain tumors of which twenty were localizedby the scan ( 80%). Of the five missed, four were slow-growing tumors which had obviouslyabnormal skull x-rays. There were 18 other positive scans due to AV malformation, vascularocclusions, cerebral contusions, brain abscesses and meningitis.

We have found the brain scan to be of considerable assistance in the diagnosis of intracranial lesions in the pediatric age group.

27. “Evaluation of Ethiodol for Lung Scanning.― ROBERT C MEADE, PHILIP P.RUETZ, AND KARL PINTAR, ( Radioisotope and Laboratory Services, Wood

Veterans Administration Center, and Marquette University School of Medicine, Milwaukee, Wisconsin)

Ethiodol 1131 has been suggested as a suitable agent for lung scanning. When mixedwith serum and agitated, the ethiodol forms only a few small particles. This does not appear tobe satisfactory for even distribution. The material can be homogenized with serum andparticle size regulated by the serum: ethiodol ratio. For this study, particles mostly below 5microns and all below 10 microns in diameter were used. The safety and distribution of thismaterial was investigated in rats, guinea pigs, and dogs.

The lethal does is between one and two ml of ethiodol per kg. If injected rapidly, oneml per kg may be acutely fatal. In such cases, frozen microsections demonstrated the oil in thecapillaries. With slower rates of injection, localization in the lung apparently happens bypinocytosis in the first circulation. Between 75 and 95 per cent of the total body radioactivity remains localized in the lungs. The biological half-life averaged six days, allowingsatisfactory scans for two weeks following injection. Less than ten per cent was found in theliver and the remainder appeared evenly distributed throughout the body. Since the doserequired for lung scanning is 0.0003 to 0.003 ml per kg, it appears to have an adequatesafety margin. The density makes it somewhat unsatisfactory, as it localizes in the mostdependent pulmonary vascular bed.

28. “Radioactivityfrom Labeled Precursors of Melanin in Mice and Hamsterswith Melanomas.―1 DONALD A MEmii, Wn.UAM H. BEIERWALTES, AND RAY

MOND COUNSELL, (Department of Internal Medicine [Nuclear Medicine],and the School of Pharmacy, University of Michigan Medical School, AnnArbor, Michigan)

In a repetition of the work of Blois and Kallman and of Hempel and Deimel studyingthe tissue distribution of radioactivity concentration following injections in mice with melanomas of DL-3, 4-dihydroxyphenylalanine-2-'4C( dopa), DL-dopa-1-14C, and L-dopa-3H,little incorporation of radioactivity was found in the melanoma. A maximum 14C concentrationratio of melanoma:serum of 4 was attained at 24 hours. Radioactivity in a more pigmentedarea of a Syrian hamster melanoma varied from 6.3-33.4 times that of serum. The uptake of14C appeared to depend to a large extent upon the degree of pimentation. Pretreatment withpyrogallol, a competitive inhibitor of catechol-o-methyl-transferase, the enzyme most responsible for the degradation of circulating catecholamines, did not enhance uptake in the adrenalgland. Administration of 14C and 125I-labeled 5,6-diacetoxyindole derivaties failed to resultin concentration of radioactivity in melanoma or adrenal, possibly because an earlier precursor of melanin enters the melanosome before these late metabolic steps occur.

1Supported by NIH Grants CA-5134-03 and CA-08429-02, the Michigan Memorial Phoenix Project #317, the Nuclear Medicine Research Fund, and the American Cancer AssociationPRA-18.

392 ABSTRACTS

29. “BoneScanning with Strontium-85 and Strontium-87m.―R T MoiuusoN, R. E.PETERSON, AND F. Bi@orr, (Department of Radiology and Radiation Research Laboratory, University of Iowa, Iowa City, Iowa)

Two hundred patients suspected of having bone metastases were scanned using strontium85 nitrate and/or strontium-87m nitrate. The results are evaluated and compared with radiographs. Strontium-85 and strontium-87m are compared with regards suitability of radiations,ease of use, patient radiation dose and accuracy of detection and localization of bone metastases.

30. “Histopathologic Studies after Prolonged Co-Precipitate Microembolism ofCerebral Capillaries.― EDTJABDOS Mimuiw, ROBERTOE. MAASS, ANDCELIAR.CERVANTES, (Comisión Nacional de EnergIa Nuclear, Dirección déMedicina Nuclear, Mexico City, Mexico)

In a previous publication we reported on our histopathologic investigation on potencialcerebral micro-infarcts as a result of the use of Taplin's technique for brain scanning withmacroaggregates of 131! radioalbumin. Using five to ten times the probable dose necessary tocarry out the study in human patients, we injected the carotid artery in twenty-five rabbitsand allowed them to survive from five minutes to ten days. From the clinical autoradiographicand histopathologic standpoints, we could not discern any adverse effects as a result of themicroembolism of approximately one out of fifty cerebral capillary blood vessels. Nonetheless,the method does present the drawback of a relatively rapid disappearance of the effective radioactivity. Consequently, it was no longer possible to recognize the exact site where the particleswere detained. One of us ( R.M.E. ) developed a method for the preparation of co-precipitatesof stannous hydroxide labeled with 198Au (half-life of 64.8 hours). Working with these, wehave been able to perform long-term autoradiographic observations.

Microscopic control revealed that 95% of the co-precipitates measured from 6.3 to 60.2micras in greatest diameter. They were administered to twenty-five rabbits in the mannerdescribed above in 50-100 microcurie doses and it was found that there were coprecipitateslodged in cerebral capillaries with sufficient radioactivity for autoradiographic studies up tofifty hours after injection. The clinical autoradiographic and histopathologic observations wereonce again negative. These findings point up the probable safety of perfusion studies usinglong-lasting coprecipitates as a carrier for tracer radionuclides.

31. “Cerebro-PulmonaryScan with iodine-131 MAA as a Quantitation of Intracerebral Arterio-Venous Shunting.―TERUONAGAI, KEIJI SANO, AND MINORUJINB0, (National Institute of Radiological Sciences, Chiba, Japan, andDepartment of Neurosurgery, University of Tokyo, Tokyo, Japan)

Although some information can be obtained by a conventional cerebral angiography, thepotential value of the technique has not been fully exploited in the quantitative measurement

of the blood flow through the vascular malformation.In the present investigation, we have developed a new radioisotope scanning technique

with 131J MAA for this purpose. Fifty to 300 @C.of 131! MAA was injected into the commoncarotid artery of patients with intracerebral arteriovenous malformation before and aftersurgical treatment. Immediately after injection into the artery on the diseased side, the lungsbrain uptake ration was determined to assess quantitatively the shunt flow. Profile scancovering the skull and lungs was performed with a linear scanner. In some patients, cerebralhemisphere scan and lung scan were carried out.

The lungs-brain uptake ratio with this technique in normal control was 37.0%, while theratios in patients were 1297.4% (case 1), 381.4% (case 2), and 579.5% (case 3). After surgicaltreatment (case 1; artificial embolization with the intraluminal application of liquid plastic,

FOURTEENTh ANNUAL MEETING 393

dimethyl polyciloxane, plus clipping, case 2; extirpation, case 3; artificial embolization withthe liquid plastic plus efferent ligation ) the ratios were markedly decreased respectively(case1; 39.2%,case2; 10.1%,case3; 6.1%,expressedin percentageson thepreoperativeratio).

The absence and decline of the accumulation in the lungs shown by profile and areascans served also to indicate that the surgical procedure had been effective.

In this study no brain insult was revealed clinically. The fact that our method is avaluable adjunct in assessing the effectiveness of surgical treatment makes it great value tosurgeons involved in neurosurgical procedures of intracerebral arteriovenous malformation.

Further studies will be presented.

32. “AnimalToxicity Studies of a Ferric Oxide Colloid Suitable for MarrowScanning.―BnL NELSON, R. L. H@YES, AND C. L. EDWARDS, ( Medical Division, Oak Ridge Institute of Nuclear Studies, an operating unit of Oak RidgeAssociated Universities, Oak Ridge, Tennessee, under contract with the

United States Atomic Energy Commission)

Previous animal studies have shown that colloidal hydrous ferric oxide labeled with 68Gacan be used for scanning of red marrow (J. Nuci. Med. 7:335-336, 1966). Much of the colloidgiven I.V. is taken up by the liver and spleen, but marrow deposition can be enhanced bycontrolling the gelatin stabilizer, the particle size and the number of particles administered.This report concerns studies of the possible toxicity of the optimum preparation preliminaryto clinical use. No deleterious effects were noted in the rabbit and dog after intravenous dosesup to 10 mg/kg. Histologic studies showed no reaction to the colloid. Prussian blue stainsdemonstrated aggregates of iron-containing material in histiocytes of the marrow, liver, andspleen within two hours after injection. These intracellular aggregates were subsequentlyresorbed so that no excess of stainable iron was found in tissues of dogs and rabbits 35 daysafter an I.V. dose of 1 mg/kg (the dosage planned for human use). Resorption of the colloidwas confirmed by preparing it with iron-59. After a brief delay, the injected tracer enteredthe iron pooi and was incorporated into red cells; iron from the colloid was utilized morerapidly in iron-deficient dogs. Similar results were obtained in the rabbit. No significanthistologic abnormalities were detected in the lungs, adrenals, or kidneys.

33. “Quantitationof Lung Ventilation and Perfusion by Scintillation Camera andXenon-135 in Man.―M T NEWHOUSE,F. J. WiuGIrr, G. K. INGHAM, ANDL. B. HUGHES, (McMaster Uni@i@iity and St. Joseph's Hospital, Hamilton,Ontario)

An Anger Scintillation Camera was interfaced to a multichannel Analyzer and the datastored on tape compatible with an IBM 7040 digital computer. This system was used todetect the distribution of 135-xenon in the lung after it has been delivered by both intravenous injection in saline solution and after inhalation as xenon gas. The subject's lung wasthen equilibrated with 135-xenon of known concentration in a spirometer. The IBM 7040could thus be programmed to calculate the ventilation and perfusion per unit volume oflung and the ventilation—perfusion ratio for each of approximately 40 2.5 X 2.5 cm. squares.

From apex to base within each vertical lung slice in normal seated subjects, there was asmoothly progressive increase of ventilation per unit lung volume of 30%, while perfusion perunit volume increased 3-4 fold.

At the apex the ventilation—perfusion ratio was approximately 3, while at the base itaveraged 0.8.

Within horizontal lung slices, no major ventilation or perfusion gradient was apparent.This system provides a reliable and rapid means for the topographic quantitation of ventilation and blood flow in the human lung.

394 ABSTRACTS

34. “Studyon the Preparation and Metabolism of Macroaggregated Albumin.―H OGAWA,H. NoGt@.n, M. 110, H. Ui@A, AND T. ISim, (Tokai Laboratory,Daiichi Pure Chemical Company and University of Tokyo)

The preparation method of macroaggregated albumin ( MAA) labeled with iodine-131have been evaluated and reported previously by the authors.

In the present study the influence of the temperature of heating and the duration ofvibration in the preparation procedure on the growth of MAA grain are investigated. Variousbatches of MAA were produced by applying several different conditions and the particle sizes(Stokes'diameter) weremeasuredusing“Hitachi-particlesizeanalyzermodel2―.

Then all information was fed into a computer, and statistical analyses, such as x2 testand least square method, were performed. It was found that the particle size of MAAincreased with the higher temperature and the longer vibration duration applied, but thegrowth of the particle slowed down and stopped at a temperature more than 90°C, if thevibration duration was longer than a certain period.

The duration of vibration and the size of MAA grain show a strong positive lineardependence. Analysis of the actual data gave the following regression equation.

Z(u) = —41.31+ 53.16 (0 c/100) + 26.55 (t(mlfl)/40)As this equation shows, the particle size ( weight mean diameter ) can be controlled satisfactorily by the fixed temperature at 80, 90 or 100 c and regulated duration of vibration.

After the MAA intravenous administration, metabolites in human urine was chemicallyanalyzed. Approximately 90% of 131! was excreted as iodine. The rest of 1311 was found aslabeled mono-iodotyrosine and thyroxin. Labeled peptide was not found as the metabolitein the urine.

35. “ColonScanning with Technetium-99m Pertechnetate.― DENNIS D PATrON,AND ROGER T. CRENSHAW, (Department of Radiology S@iences, Universityof California, California College of Medicine, Los Angeles, California)

Scans of the colon were obtained 12 to 24 hours following I.V. administration of 99mTc@pertechnetate. The principal route of entry into the colon appears to be via the bloodstream,rather than the intestinal lumen, and the isotope appears to be transiently concentrated in thecolonic mucosa prior to its release into the lumen and stool. By taking advantage of this effect,one can visualize the colonic mucosa on an abdominal scan. The pathway was investigatedin normal controls and in patients with obstruction, ileus, or double colostomy. The compartment turnover of pertechnetate is discussed in relation to other radiologic studies ofthe gastrointestinal tract.

Scans of the abdomen at appropriate times after I.V. administration of pertechnetatecan be used to demonstrate mucosal and vascular lesions of the colon. The estimated radiationdose to the colon is about 1.5 rads. The technique appears to have value as an adjunctto the barium enema; the colon scan offers a method of visualizing the colonic mucosa,while the barium enema demonstrates the lumen. Clinical applications are demonstratedand discussed.

36. “TheUse of Small Aquarium Fish in Radioisotope Research.― JOSEPH LRABINOWITZ, AND JONATHAN GLAUSER, (Radioisotope Service, Veterans Ad

ministration Hospital, Philadelphia, Pennsylvania)

During developmental work on several projects it became necessary to measure thetotal body radioactivity of the specimens being considered. Our laboratory does not havespecialized laboratory equipment for this purpose. It occurred to us that aquarium fishwould be an excellent model and because of their small size, radioactive measurementwould be simplified. Total body radioactivity of a small fish can be determined by simplyplacing the fish with a few ml of water in a centrifuge tube and counting the test tube ina crystal well scintillation counter or a “NancyWood―counter.

FOURTEENTH ANNUAL MEETING 395

(A) The useof smallfishpermittedthe investigationof changesin permeabilitytindercontinuous topical application. For this purpose two beakers were used, each of these containing 10 small fishes (i.e. glow tetras). Both beakers contained the indicator radioactivematerial ( dyes, ions, drugs, etc. ) . To one beaker, the agent under study was introduced.At giventime intervalsfishare removed,washedand assayedfor radioactivity.

(B) Studyof radio-protectiveagentswasalsopossible.A strongradioactivematerialwasplaced in both beakers (enough to give a LD50 in 10 hours). To one beaker was added theradio-protective agent.

37. “TheDistribution of Labeled 4@'lC Cholesterol in Terminal Patients.― JOSEPHL RABINOWITZ,AND RALPH M. MYERSON,(Radioisotope and Medical S@i@vices, Veterans Administration Hospital, Philadelphia, Pennsylvania)

Tissue analysis for specific activity of 4-14C-cholesterol was performed on many patientswho died between one day and one year after receiving 20 microcuries of 4-14C-cholesterolintravenously. Different tissues were removed at postmortem, among these were liver, kidney,spleen, lung, etc. The tissue material was saponified and the total cholesterol extracted andprecipitated with digitonine. The cholesterol-digitonide was dissolved in methanol and aliquotsprepared for assay. Some aliquots were used for radioactive measurement by liquid scintillation. Other aliquots were used for Chiamori's colorimeric cholesterol assay. Specific activitywas then determined for each tissue. Results were compared to the activity of the circulatingcholesterol sera. The evidence obtained suggests that serum cholesterol equilibrates rapidlywith certain tissue but exceedingly slow with others. Analysis of large organs indicated smalldifferences between lobes or regions of these organs.

38. “Stomach Scanning with Radioiodinated Toluiten Red (Neutral Red).―

FELICITOS CALLEJAS RAMOS, AND RAiJL ALVAREZ T0STAB0, ( Laboratorio deRadioisotopos, HospitaF't@i RãZa,―Instituto Mexicano del Seguro Social,Mexico City, Mexico)

The radioiodinated toluilen red (131!) was labeled by the first time in Mexico 1, forgastric studies. The new tagged molecule was assayed for activity, purity, sterility andtoxicity by the usual methods. Using several kinds of laboratory animals, the metabolism wasstudied. Finally, the radioactive dye was used in human beings for studying the gastricfunctions.

This communication includes the experimental gastricscans both, mucous (directly) andwall (indirectly). The experimental work was divided in two different steps, one for determining the optimal dose and the best elapsed time for scanning; the other step was the utilization of different well-known substances which permit clear images without the interferenceof other organs and which also metabolize the dye, as in the liver.

The TALPRAN was the best inhibitor of gastric secretion for no accumulation of theradioactive substance in the gastric cavity. The stable toluilen red and the sulphonbromphtalein blocked partially the clearance activity of the liver.

The main conclusions are as follows:1.—With the radioiodinated toluilen red given intravenously, it was possible to obtain

clear mucous gastric images if one inhibit's secretion substance was used.

2.—In the case of gastric ulcer, the radioactive area of mucous gastric detected is less,but more active than in normal cases.

3.—In the case of piloric stesis, the area is bigger but less active than in normal cases.4.—When the gastricscans were compared with the respective radiological images, there

were great similarity and in some cases it was possible to understand a few scanningsapparently unintelligible.

396@ ABSTRACTS

39. “SplenicSequestration of Heat-Treated Chromium.51 Tagged Red Cells inHepatosplenic Bilharziasis (Schistosomiasis).―M A Riizz@, A. M. HIc@tzx,M. A. RIFAAT, F. Gii@4rnu@ A. A. ATA, S. ABSEL-HALIM,AND I. KAMEL,(Departments of Medicine, Surgery, Tropical Medicine and Pathology,

Faculty of Medicine, Cairo University, U.A.R.)

Hepatosplenic bilharziasis is caused by an intravascular parasite that inhabits the portalvenous system leading to hepatic fibrosis, portal hypertension and late involvement of theliver parenchyma. In this disease, splenic enlargement is more constant and more marked thanin the other forms of cirrhosis. Pathologically the bilharzial spleen is characterized byreticular hyperplasia and marked engorgement of the sinusoids.

In the present study, a modified heat-treated 51Cr-tagged red cell method was used toevaluate the avidity of the spleen in removal of altered cells from the circulation in 78subjects ( 24 normals and 54 bilharzial patients representing different grades of this disease).

In the normals, the disappearance half-time of radioactivity from the circulation (Ta)

amounted to 172 ±69 minutes ( Mean ±1 S.D. ), the range being 74 to 280 minutes.Using this technique in bilharzial patients, the results were extremely variable. In 8

patients with active urinary and/or intestinal bilharziasis without visceral manifestations,T@ was within normal limits. In contradiction, T1 of the 46 patients having hepatosplenic

affection ranged between 30 and 280 minutes, with 14 cases below 74 minutes (lowestfigure obtained in normals ) . As regards the cause of this rapid disappearance of altered cells,results of the present study point to the spleen as being the cause. Thus, when heat-treatederythrocytes from a normal donor were injected into a bilharzial patient, the same T@ was

obtained; whereas, when the patient's cells were injected into a normal recipient, T3 waswithin normal limits. Furthermore, splenectomy caused marked prolongation in the disappearance half-time of heated-cells. In addition, by surface counting, the spleen/liver ratioin 9 bilharzials was found to be 5.5 ± 1.8, which is significantly higher than both normalsand patients having splenic enlargement from other causes, such as leukemia. However,there was no correlation between the size of the spleen and its trapping of heated-cells inbilharziasis.

When present, this exaggerated splenic trapping function should be considered anindication for splenectomy.

40. “HighSpecific Activity Technetium-99m Albumin.―1 P RICHARDS, AND H. L.

ATKINS, (Brookhaven National Laboratory, Upton, New York)

High specific activity OOmTc@labeledhuman serum albumin is of importance in certainapplications in nuclear medicine and is essential in the preparation of macroaggregatedalbumin for lung scanning. A number of procedures have been reported for labeling albuminwith 99mTc; generally, all are similar, with modifications in amounts of reagents and pH adjustments. Some difficulties have been encountered in achieving consistent high yields andmost methods result in relatively low specific activities.

A systematic examination of the chemical steps involved has been made to determinetheir importance, if any, and to find the optimum conditions to give the maximum yield oflabeled albumin. The pH of the initial aOmTc solution, the amounts of Fe+3 and ascorbicacid, the pH adjustment prior to the addition of albumin, the amount of albumin and thepH adjustment to initiate labeling have all been found to play an important role in thefinal yield.

A procedure has been developed that will reproducibly give labeling yields greaterthan 75% with as little as 5 mg of albumin. As a result, high specffic activity material canbe produced with relatively small amounts of 9OmTc activity. Macroaggregates more than1 mC/mg suitable for lung scanning are readily prepared by heating the labeled albuminfor several minutes in boiling water.

1This work was performed under the auspices of the U. S. Atomic Energy Commission.

FOURTEENTH ANNUAL MEETING 397

41. “LungScanning in Chronic Respiratory Disease.― OSCAR M POWELL, ANDE. RONALDRIGGALL,(Nuclear Medicine Laboratory and Section of Pu!monary Diseases, Samuel Merritt Hospital, Oakland, California)

This is a preliminary report of observations made in correlation of findings in 34 patientswith chronic respiratory disease in whom both pulmonary function studies and lung scanswere obtained. Lung scans have been performed in a total of 115 patients with chronicrespiratory disease; in 34 of these patients, obstructive pulmonary disease was found bypulmonary function studies, but was undifferentiated except by degree.

The lung scans demonstrated pulmonary perfusion patterns by use of radioiodine 131!tagged macroaggregated human herum albumin.1 Three general patterns were seen in thelung scans in these patients: ( 1 ) mottled ischemia, (2) segmental ischemia and (3)peripheral ischemia. Also seen were combinations of mottled and segmental ischemia. Thepredominant pattern was of the combined mottled and segmental ischemia. One of thesepatterns alone was uncommon. The peripheral ischemia was found in only two patients.

Pulmonary function studies did correlate well with the overall estimate of lung diseasemade by scan, but did not correlate with a particular pattern seen by scan.

These patterns of circulatory loss discerned by lung scan may lead to a differentiationin the future as to etiologic and clinical types of obstructive lung disease not presentlyappreciated.

iSupplied by Abbott Laboratories. Correspondence to be sent to Dr. Powell.

42. “TheReproducibility of Tests of Thyroid Function.―Joii@ F SCHOLER,(PaloAlto Clinic, Palo Alto, California)

A study was made to determine the reproducibility of several tests of thyroid functionwith the tests done on the same individual at different times and under clinical rather thanideal conditions. Euthyroid and otherwise normal male prisoners volunteered for tests ofBMR, PBI, Achilles reflex (photomotogram), 131! uptake at five hours, and the thyrobinding-index (TBI). Each test was repeated in two to six weeks without reference to theprevious results and the blood tests done on coded specimens.

The “reproducibility―of each test was determined by comparing the differences betweenthe original and repeat test on the same individual with the standard deviation of thetests done on the entire group. On this basis, the reproducibility of the tests from best toworst was as follows: TB!, photomotogram, PB!, 131! uptake, and the BMR. The “usefulness―of each test was determined by comparing these differences with the generally acceptedrange of normal. On this basis, the usefulness of the tests from most to least was asfollows: 131! uptake, photomotogram, TB!, PBI, and BMR.

43. “InVivo Measurement of Absolute Quantities of Radioactivity Within anOrgan.―A. G. Sciiuirz, F ROLLO,AND Km@TF. Fomj@ii, (Department ofRadiological Science, Johns Hopkins University, Baltimore, Maryland, Applied Physics Laboratory, Johns Hopkins University, Silver Spring, Maryland, and Siemens A.G. WW f. Madizinische Technik, Eriangen, Germany)

Values obtained in the measurement of organ uptake vary as a function of the unknowndepth of the organ. The variation results from attenuation of gamma rays in tissue and fromthe variation of the solid angle of the detector with the unknown distance between thedetector and the organ. Two methods are proposed for determining the effective depth ofthe organ in the patient and thereby permitting the determination of the absolute value ofthe organ uptake.

One method is based on comparing the in vivo ratio of the counting rates of gammarays of two different energies arising from the same isotope (or from two isotopes of the

398 ABSTRACTS

same element ) to the ratio of the counting rates of the same mixture in air. The difference inthese ratios is related to the known attenuation factors and the unknown depth. The secondmethod is based upon measuring the in vivo ratio of counting rates for a single gammaphoton energy for two positions of the detector. The unknown depth is related to this ratioand to external geometry of the system.

Experiments with phantom sources using a renal uptake system demonstrated thatneither method could be described by simple attenuation and geometry formulas because ofscattered photons. For a radioactive source buried in a scattering medium, the count ratefollows an exponential attenuation law as the depth in the medium is varied. The expectedadditional decrease resulting from the increased distance between source and detector iscompensated for by the relative increase in scattered photons. Computations of the countsdue to unscattered, singly scattered, and doubly scattered gamma rays, as a function ofgamma ray energy, depth of the organ, and distance of the detector from the body surfaceagree with experimental data. The methods have been used successfully to measure absolutequantities of radioactivity within phantoms of organs.

44. “lodine Concentration in Facial Structures.― JAN K SIEMSEN, BomuS CA@rz,AND RALPH E. BODEFISH, (University of Southern California School of Medicine, the Los Angeles County General Hospital, and the Veterans Administration Hospital, Long Beach, California)

Iodine accumulation by salivary glands, as well as other extrathyroidal tissues, is awell-known phenomenon. Intense iodine concentration by other facial structures has not beenreported until recently.

Fifty-four patients were studied by scintillation scanning of face and skull followingadministration of therapeutic or diagnostic doses of iodine-131. In all cases the thyroid hadbeen ablated prevously, partially or completely, by thyroidectomy and/or radioiodine fortreatment of thyroid cancer, cardiac disease or malignant exophthalmos. !ntense concentrationof radioiodine in the mucosa of the nose, the paranasal sinuses and/or the palate was demonstrated in the majority of cases.

Effective half-life studies showed that these loci handled the material like the salivaryand gastric glands with a turnover more rapid than thyroid tissue. Radio-resistance of thesetissues was indicated by the fact that concentration was observed even after numerousprevious cancericidal doses of iodine-131.

Concentration of radioactivity in nasal secretions provoked by various stimulants wasweak in some cases and absent in others. It is not obvious why some patients fail to concentrate iodine in these areas under identical circumstances.

The clinical significance of this observation lies in the fact that these areas of accumulation should not be interpreted as metastatic lesions in thyroid cancer or as ectopic thyroidtissue.

45. “Effectof Stable Calcium on Strontium-90 Absorption in Man.―1HERTASPENCER, JOSEPH SAMACHSON, EDWARD P. HARDY, JR., 1u'm JOSEPH RIvERA, (Metal@iic Section, Veterans Administration Hospital, Hines, Illinois, and Healthand Safety Laboratories, U. S. Atomic Energy Commission, New York City)

In order to investigate whether stable calcium would decrease, the absorption of 90Sr,balances of 90Sr and calcium were performed under constant dietary conditions during lowand high calcium intake. The average low calcium intake was 213 mg/day and the averagehigh calcium intake was 1718 mg/day. The high calcium intake was attained by addingcalcium gluconate tablets to the constant diet and the 90Sr intake was similar during the lowand high calcium intake, 4.8 and 5.7 pC/day. The average 90Sr balance was slightly more

1Research supported by U.S. Atomic Energy Commission.

FOURTEENTH ANNUAL MEETING 399

negative during high calcium intake, —0.36pC/day, than during low calcium intake, +0.01pC/day. Also, the net absorption of 90Sr was on the average lower during high calcium intake,6.3%, than during low calcium intake, 12.3%. However, these differences were not significant.There was no correlation between 90Sr and calcium balances, while there was a correlationbetween urinary excretion of 90Sr and calcium and between urinary excretion of 90Sr and

@Srintake. The 90Sr/Ca ratio of urine was more variable than the 90Sr/Ca ratio of stoolduring the intake of different levels of calcium and the 90Sr/Ca ratio of stool was similarto the °°Sr/Caratio of the diet.

46. “LogarithmicPlotting of Scan Surface Areas: A Function of Organ Weights.―1RICHARD P SPENCER, (Department of Radiology, Yale University School of

Medicine, New Haven, Connecticut)

For many organs, there exists a relationship between the area seen on radioisotopic scansand the organ volume or weight. A dimensional analysis of the scan surface area ( S ) revealsthat it is related to the volume (V) by: V f•53/2@Hence, log V log f + 1.5 log S.A plot of the logarithm of the surface area should thus be a linear function of the logarithmof the volume (or weight, if the density is constant). This finding can be shown to be truefor the spleen. Using values from Holzbach and co-workers for lateral spleen scans, therelationship was: log spleen weight ( gm ) —0.59 + 1.5 log spleen area (cm2). Thecorrelation coefficient was over 0.8 for data covering a 15-fold difference in spleen size.For the kidneys, the equation was: log kidney weight ( gm ) —0.18+ 1.21 log area ( cm2).Values for the kidney from a different series reveal essentially the same equation, with theexponent equal to 1.22. Variation of the exponent from a value of 1.5 can be explained byone or more dimensions growing at a rate quite different from a reference axis. Organ weightsdetermined this way can be compared with weights estimated by means of the allometricrelationship. Such an analysis can be applied to the liver in cirrhosis and likely depicts adisordered growth pattern. The simple equations probably do not pertain to grossly diseasedorgans; elucidation of the new relationships in such cases may be of use in following progressof the disease. Two useful applications appear to be found in quantitating growth of organsin individuals or experimental animals over a period of time, and in following organ regeneration.

1Supported by United States Public Health Service Grants CA6519 and AM09429.

47. “TheLate Incidence of Hypothyroidism after Therapy of Hyperthyroidismwith Radioiodine.― MAxwEu@ SPRING, (New York Medical College andBronx-Lebanon Hospital, Bronx, New York)

The incidence of hypothyroidism in the first year after therapy with RAI for hyperthyroidism is 5-10%. Subsequent to this the incidence is 2-3% per year as reported in therecent literature. Thus, in ten years 25-40% of those treated will be hypothyroid. My resultsin the treatment of 50 private patients will be reported. They were followed from 3 to 81months. There were 12 males and 38 females. Age range was 27-59 and 22-72, respectively.Two had recurrent toxic nodules following previous surgery, eight had toxic adenomas andthe remainder had Graves disease. Thyroid weights ranged from 25-70 gms., most being lessthan 40 grams. The early patients were treated on the basis of 100 microcuries per gram oftissue for Graves and 125 microcuries for the nodular type. Later dosage was based ondelivery to the thyroid of 80 and 100 millicuries of RAI per gram of tissue respectively.Fifty per cent required one dose and three patients three or more doses. Most received 3-5mC. Four patients have been followed from three to eleven months and the remainder fromthirteen to eighty-one months. Three patients, 2F and 1M, became hypothyroid during thefirst year after therapy and remained so. None of the others have shown any evidence ofhypothyroidism to date. The results are in marked contrast to those reported.

400 ABSTRACTS

48. “TheSignificance of Shine-Through on the Side View Lung Scan.―E LSURPRENANT, N. BROWNING, L. R. BENNETT, AND M. M. WEBBER, (Depart

ment of Radiology, University of California, Center for the Health Sciences,Los Angeles, California)

“Shine-through―refers to the per cent of the detected radioactivity which originatesfrom regions beyond the depth of interest. The significance of shine-through from the distantlung when a lung is scanned from the side was determined from human and phantom experiments.

Studies were made with a rectilinear scanner ( 19-hole focus collimator, 3-inch crystal)and an Anger Camera ( non-focus collimator ) . The lung cavities of a body phantom werefilled with oatmeal tagged with 131! or technetium-99m. Measurements were made from thisphantom as well as from specially constructed phantoms in which the geometry could bevaried and from patients who perfused only one lung.

The shine-through varied with the point of measurement. At the point of maximumactivity, it averaged 30% with 131! and 24% with aamTc as measured with the 19-holecollimator. The effect of shine-through on the side scan image is determined by (A) thedegree of blurring of information from the distant lung, and (B ) the magnitude of theshine-through. The magnitude varies with ( 1 ) the diameter of the shine-through source,i.e; if its diameter is less than the area included by the collimator, its contribution to thetotal count rate is proportionately less, ( 2) the density of the internal absorber and (3) thescatter by the internal absorber. The amount of scatter detected is related to ( a ) the natureand energy of the isotope emission, ( b ) the density of the absorber, and ( c ) the size andposition of the window.

The primary effect of shine-through on the side scan image is to increase the overalldensity of the image without significantly effecting its resolution. Actually, shine-through canmore easily mask ischemic lesions in the anterior or posterior projections, since the A-Pdiameter of a lung is much wider than its transverse diameter. Thus, a side scan of eachlung is recommended in conjunction with anterior and/or posterior views.

49. “Equilibria Involved in the Trisorb Resin Test of Thyroid Function.― D. L.TABERN, Jom. KEARNEY, AND ANNE DOLBOW, ( Louis A. Weiss Men@@1

H@jital, Chicago, Illinois)

The binding of T-3 or T-4 by red cells or resins is commonly regarded as a “oneway―phenomenon, reaching equilibrium in a few hours. The widely variable results in the literaturestrongly suggest that multiple variant dependent equilibria are involved. The fixed geometryTrisorb sponge seemed an excellent means for establishing and quantitating such equilibria.

It was established that the presence of the supporting polyurethane foam materiallyalters the effective surface, both as far as absorption and desorption are concerned. There aretwo degrees of binding: one which persists for several hours, being largely reversible andanother which happens slowly and is almost nonreversible. Both are strongly dependent ontemperature.

The rate and extent of transfer of T-3 from binding proteins to resin are materiallychanged by ions as biologically common as NaC1 and Na!. Quite surprisingly, they are notinfluenced by cold T-3 or T-4 in several thousand-fold concentration and bear little relationto the results of dialysis experiments.

These observations seemed to suggest the mildest possible incubation conditions and theuse of multiple standard sera of constant binding composition in the clinical procedure. Wehave shown that by using 00 instead of 20-25° there is a pronounced shift in equilibria insuch a way as to give a much sharper distribution pattern, especially on the low side wherehypothyroidism has been difficult to differentiate.

This report will cover some 1500 clinical determinations, as well as repeat studies on aseries of 15 standard sera of known history and composition. This data will be related toelectrophoretic studies on these sera.

FOURTEENTH ANNUAL MEETING 401

50. “Preparing and Dispensing Xenon-133 in Isotonic Saline.― Ro@ S. TILBURY,

Hsrmy H. KRAMER, AND WERNER H W@uiL, ( Neisler Laboratories, Inc.,Union Carbide Corporation, Tuxedo, New York)

An apparatus and procedure is described for the preparation of known uniform concentrations of 133Xe in isotonic saline solution. Also described is a method of containing thissolution without contact with a gas phase and dispensing it so that a known dose of ‘33Xecan be injected into the patient.

Fission product xenon-133 is transferred from a storage container into a sterile evacuatedglass bulb containing the required amount of sodium chloride. Sterile, pyrogen-free water isdegassed in an attached reservoir and then transferred under vacuum to the bulb containing133Xe until the bulb is full. The gas, salt and water mixture is stirred until dissolution iscomplete, producing a sterile isotonic saline solution. The 133Xe concentration is controlledby the 133Xe transferred to the system and by the available volume of the dissolution bulb.

The ‘33Xesaline solution is dispensed into special cartridges consisting of glass tubes fittedwith a rubber piston at one end. The cartridges are filled to overflowing and sealed with a rubber septum in a manner that avoids formation of a gas space. The 133Xe activity and concentration is determined by assaying each cartridge.

To insure that repeated doses of ‘33Xein saline of known concentration are obtained, the133Xe saline solution must be dispensed so that no gas bubble is created in the cartridge.This procedure is accomplished by placing the 133Xe-saline cartridge in a CARPULE ASPIRATOR with the septum exposed. The dead space of a tuberculin syringe is filled with sterileisotonic saline solution and the sterile septum is pierced with the hyperdermic needle. Thepiston rod of the CARPULE ASPIRATOR is then depressed so that the 133Xe-saline solutionis forced out of the cartridge and into the syringe without creating any gas space in eitherthe syringe barrel or the cartridge. The needle is then withdrawn from the cartridge septumand the syringe is ready to inject a measured volume of known concentration. The solutionleft in the cartridge is available to fill additional syringes in the same manner.

51. “Evaluationof the H-3 Labeled Digitonin Method for Serum CholesterolAssay.―H. UnA, M 110, M. MoTomu, S. MuRAo, S. KATO, ( University ofTokyo, and the Dainab@ Radioisotope Laboratory, Tokyo, Japan)

In spite of the necessity of an accurate method to measure serum cholesterol in metabolicdisorders, conventional methods were not satisfactory because of the instability and sensitivityto light and temperature of the reagent.

In order to eliminate the step of colorimetric assay after preliminary purification, the useof H-3 labeled digitonin method was introduced by Cardinal and Miller (Abbott Lab.)

When compared with the method reported by Morris, the former method has the advantage in its further simplicity. Therefore, clinical evaluation of this method was performed.

In principle, an extraction procedure by acetone-alcohol followed by precipitation withH-3 digitonin, the cholesterol digitonide is allowed to crystallize over night at room temperature. Supernatant is then measured for radioactivity by liquid-scintillation counter. From thestandard curve (amount of cholesterol versus c.p.m. in the supernatant), cholesterol level isobtained.

Standard calibration curve indicated good linear relationship between the serum cholesterol level and count in the supernatant with straight flexion over 500 mg/dl level, probablydue to the formation of different molecular compounds.

Reproducibility of this method is quite satisfactory with standard deviation of 1.2-4.2%.Comparison of the cholesterol levels obtained by this method with those obtained by

the autoanalyzer method indicate a fairly close relationship; however, because of the poorreproducibility of the latter method, no definite correlation was found.

This method proved to be useful for the accurate and reproducible assay of cholesterol.

402 ABSTRACTS

52. “Diagnostic Value of Lung Scans in a General Hospital Population.― THOMASA VEBDON,JR., BRUCEF. CHANDLER,NICHOLASTHURMOND,(RadioisotopeClinic, Letterman General Hospital, San Francisco, California)

The value of lung scans in detecting pulmonary emboli has been well-proven in recentyears. By means of a study group involving patients who were presented to the Chest Serviceof a large general hospital, we have found that the lung scan performed with macroaggragated1311 albumin has been helpful in the evaluation and treatment of many conditions other

than just diagnosing pulmonary emboli.Analysis of 130 scans performed on 113 patients with various pulmonary conditions

revealed that the scan was positive on 81 occasions ( 62%).

To be emphasized in this study was the value of the scan in evaluating patients withbronchogenic carcinoma, with 25 of 27 ( 92%) scans positive, frequently indicating far moreimpairment of pulmonary artery blood flow than was suspect from the standard chest x-ray.

Also striking were the changes in saccular bronchiectasis, with 10 of 12 scans ( 83%)positive, revealing alteration of pulmonary blood flow that was not suspected from the conventional chest x-ray.

A wide spectrum of other pulmonary conditions gave positive scans indicating far morepulmonary artery involvement than had been suspected previously.

Appropriate scans, x-rays and angiographic studies will be shown to illustrate the widevariety of pulmonary pathology that will yield a positive lung scan with macro-aggragatedalbumin iodine-131. The value of the scan in determining prognosis and therapy, as in thecase of bronchogenic carcinoma, will be discussed.

53. “Significanceof Spleen Pickup of Radioactive Gold-198.― THOMAS A VERDON JR., O'NEILL B@uui@Tr, JR., FRANK PANETTIEBE, ( Radioisotope Clinic,

Letterman General Hospital, San Francisco, California)

Liver scans performed by the use of radio gold-198 are effective in outlining the shapeof the liver and detecting space-occupying lesions. Additional information is available on theliver scan if significant spleen pickup of radio gold occurs.

We have noted that such pickup occurs in at least five diverse groups of conditions:(1) Patients with portal hypertension secondary to fibrotic processes of the liver, such ascirrhosis, will have splenic and bone marrow uptake depending upon the degree of portalhypertension. This finding has been an invaluable aid in the diagnosis and management ofpatients with this form of hepatic disease. (2) Spleen pickup is noted in patients withmyeloproliferative diseases, such as chronic granulocytic leukemia, polycythemia vera andmyelofibrosis. (3) In patients with primary reticuloendothelial cell disease, such as lymphoma,striking spleen pickup is also noted. Here it is postulated that the degree of activity is dueto hyperfunction of the reticuloendothelial cells. (4) We have observed spleen pickup inmost patients with malaria. This has not been found to occur in other chronic infectiousdiseases studied. (5) In patients with diffuse infiltrative diseases of the liver, such assarcoidosis, schistosomiasis or military tuberculosis, if spleen pickup occurs, liver biopsyusually confirms the presence of infiltrative liver disease.

In summary, spleen pickup of radioactive gold is a nonspecific occurrence seen in amultiple variety of clinical conditions. When interpreted in view of the proper clinical setting,it is a significant valuable diagnostic tool.

Appropriate scans and biopsy specimens will be shown to illustrate the various groupsof diseases.

54. “TheUsefulness of the Liver Scan in Detection and Treatment of AmoebicAbscess.― THOMAS A VERDON JR., GEORGED. HAMILTON, ARTHUR COHEN,

FOURTEENTH ANNUAL MEETING 403

(Radioisotope Clinic, Letterman General Hospital, San Francisco, California)

The use of the liver scan in detecting space-occupying lesions of the liver has provento be a valuable diagnostic procedure in patients returning from Southeast Asia, whereamoebic infestations are common.

The ability to detect abscesses of the liver has afforded new insight into the basic natureof this disease and has made surgical exploration and drainage a procedure which until onlyrecently was condemned, a now accepted mode of therapy.

Three cases will be presented to show the wide spectrum of disease that may be encountered. Symptoms have ranged from severely ill, moribund patients to totally asymptomaticpeople with large abscesses in their liver.

It is to be expected that as more Americans return from Southeast Asia this problemwill be encountered with increasing frequency in Radioisotope Laboratories.

55. “Full-Size Scinitiphotos from the Scintillation Camera.― MIL0 M. WEBBER,

AND L. R. BENNErr, (Department of Radiology, University of California at

Los Angeles, Los Angeles, California)

This paper will describe an enlarging camera which can be mounted on the scintillationcamera output oscilloscope. The integrated image photographed from this oscilloscope screencan be enlarged to the size of the object being examined. This system provides scintiphotosthe same size as roentgenograms and does away with the disadvantages in the response ofpoloroid film. Scintiphotos made in this manner appear to be very acceptable to radiologistsand referring physicians who are used to full-size read out.

56. “TheSimultaneous O1HA and Renografin Renograms and Clearance Determinations in Patients.― F C WATTS, C. D. MAYNARD, R. DEARMAS, I.MESCHAN, AND R. WITCOFSKI, (Department of Radiology, The BowmanGray School of Medicine, Winston.Salem, North Carolina)

The sometimes complex renal function studies utilizing tagged compounds for renogramsand clearance studies performed consecutively have been performed simultaneously in patients.The method used employs a single injection technique of both O125!HA and 131! Renografinand a dual-channel spectrometer for energy differentiation yielding four renogram curves.

Clearance values, total and differential, are presented for each of the patients in the series.

57. “Demonstrationof the Vascularity of the Femoral Head.―M M WEBBER,L. R. BENNETT,JOSEPHWAGNER,AND DENNiS L. PATTON, (Department ofRadiology, University of California at Los Angeles, Los Angeles, California)

In the management of hip diseases, it is desirable to have knowledge of the femoral headblood supply. Waiting for the healing of a fracture or for the clearing up of an arthriticcondition may at times be futile and result only in discomfort on the part of the patient andeventual implantation of a prosthesis. Prognosis in many such cases rests upon the presenceor absence of adequate blood flow to the femoral head.

Demonstration of the bone marrow is possible by virtue of the phagocytic cells presentwithin it. Such phagocytic cells pick up colloidal particles carried to them if their bloodsupply is intact. Scanning procedures are able to demonstrate effectively the in vivo locationof radio-tagged tracers. Colloidal tracers such as radio-technetium99― sulfide demonstrate verysatisfactorily the distribution of bone marrow within the human skeleton.

404 ABSTRACTS

Technetium sulfide in these studies was prepared by the method originally suggestedby Patton and associates. Patients were given approximately ten millicuries of the tracersubstance. One-half hour following the injection, scintiphotos of the pelvis were made. It isseen that the femoral heads in normal individuals pick up somewhat less of this colloidalsubstance than do other areas of the long bones. However, sufficient tracer is localized thatthe presence of activity in the region of the femoral heads can be ascertained even thoughresolution of the actual form is difficult to perceive. This study will compare the normalappearance with the appearance seen in patients who have known hip disease.

58. “ElectronicAnalogue Contrast Enhancement.―MIL0 M WEBBER,ELWOODDEWIG, ANDRAYMONDL. SMITH, (Department of Radiology, University ofCalifornia at Los Angeles, Los Angeles, California)

In the visualization of scan pictures and scintiphotos, it is desirable to demonstraterelatively minimal changes in the density of the black and white images so that all canappreciate the difference and accept it without equivocation.

An application of the techniques of color television to contrast enhancement has beenmade. The system consists of a television camera which, in effect, scans the black and whitephotoscan ( which is made in the routine manner ) . The video signal so produced is thenelectronically made to control the level of activity of the three color guns of the colortelevision tube. The control of these colors is continuously variable so that the scale of colorscan be changed while the scan is being viewed. In this way, proper adjustment will permitmarked contrast enhancement. Slight differences of grey can be made to correspond to avery obvious and unequivocal change in color. This system is especially useful in demonstration of scans to referring physicians and in conferences when there is a question of isotopeconcentration. The ability to change the relative setting of the colors results in a backgroundcutoff type response. It is therefore possible to scan with very low or with no backgroundsuppression or contrast enhancement. Enhancement can be added at a later time when thescan is being viewed with the electronic color contrast.

59. “TheUptake of Technetum-99m Pertechnetate by the Choroid Plexus.―1 R. L.WITCOFSKI, C. D. MAYNARD, AND R. JANEWAY, (Departments of RadiI@@

i@d Neurology, The Bowman Gray School of Medicine, Winston-Salem,North Carolina)

In the performance of over 3000 99mTc pertechnetate brain scans, we have observedmore than 30 patients with marked uptake of the radlionuclide by the choroid plexus. Effortsto block the uptake with iodide (Lugol's solution) have been partially effective; the uptakeis completely blocked with prior administration of 200 mg of potassium perchlorate. (Thisfact implies an active concentration process.) Experiments were undertaken in rabbits todetermine if this accumulation was indeed active concentration by the choroid plexus. Afterprior administration of blocking agents, OOmTcpertechnetate was injected and the rabbitssacrificed at specified time intervals. The choroid plexus of each lateral ventricle was dissected out and assayed in a well counter. There was an active concentration of pertechnetateabove blood levels at one hour and this concentration steadily increased up to four hours.Prior oral administration of potassium perchlorate blocked this uptake. Other agents (Lugol's,etc.) were less effective.

1Partially supported by a grant from the Forsyth Cancer Service.

60. “Quantitation of the R.I.S.A. Aerosol Distribution in the Normal HumanLung.― F J WRIGHT, M. T. NEWHOUSE, G. K. INGRAM, AND L. B. HUGHES,

(McMaster University and St. Joseph's Hospital, Hamilton, Ontario)

By means of the Anger Scintillation Camera suitably interfaced to a multichannelanalyzer and tape data storage, the distribution of R.I.S.A. (mean size 3u) delivered by an

FOURTEENTH ANNUAL MEETING 405

ultrasonic nebulizer was determined in five normal subjects. The tidal volume and respiratoryrate was carefully controlled. By equilibrating the subject's lung with a known xenon-135concentration in a spirometer just prior to aerosol inhalation, data were obtained whichallowed a volume calibration and thereby enabled aerosol distribution to be expressedtopographically in terms of R.I.S.A. deposition per unit volume of lung. (Aerosol Index).The results obtained were compared with the distribution of a single breath of inhaledxenon-135. In general, there was a progressive increase in the areosol index from lung apexto base which followed the ventilation gradient. In contrast to xenon-135 distribution, however, there was also a marked lateral gradient of decreasing aerosol distribution frommediastinum to lateral chest wall. These data suggest that the distribution of aerosols in thelung is not a precise reflection of the distribution of ventilation.

61. “ElectronicCounting, Size Distribution and Size Control of Radio AlbuminMacroaggregates in Suspension.―1 ROBERT M ZUCKER, BENEDICT CASSEN,GEORGEV. TAPLIN, AND JOHN C. KENNADY,( Laboratory of Nuclear Medicine and Radiation Biology of the Department of Biophysics and NuclearMedicine, School of Medicine, University of Calfornia at Los Angeles,Los Angeles, California)

The electronic counting of macroaggregates of radioalbumin consists of the passage ofthe particles suspended in saline through a small orifice containing a dense current flow,created between two platium electrodes ( Coulter counter ) . When a non-conducting aggregate enters the orifice, it displaces a volume of conducting fluid (saline) that alters theresistance to electrical current flow until the particle leaves the orifice. This change in electrical resistance is detected as a pulse which is amplified, electronically analyzed and displayedon a 400-channel analyzer. The macroaggregates with larger volumes produce a greaterchange in electrical resistance and a larger pulse.

The size of radioalbumin macroaggregates can now be effectively controlled by a processof heating and ultrasound. Ultrasound significantly breaks up larger aggregates into smallerones, while heating tends to increase their size. The particle size distribution is controlledwith the use of ultrasound and is checked by the multichannel analyzer for volume distribution and consistency in different preparations. Macroaggregates of a specific size rangecan then be used to study organ blood flow distribution by scanning.

Kennady has demonstrated that the absence of extra macroaggregates (> 60 /L) preventsthe formation of local microinfarction when they are injected into the internal carotid fordetermining relative regional cortical blood flow by the scanning technique. Adequate control of size distribution during preparation thus assures complete safety of the test agent.

Due to the porous nature of the albumin macroaggregates, the electronic size distributionappears smaller than that of solid non-conducting polystyrene sphere of similar microscopicsize. However, a relative size distribution exhibiting the presence or absence of smallpercentages of larger aggregates, is obtained.

‘These studies were supported by Contract AT( 04-1 )GEN-12 between the AtomicEnergy Commission and the University of California.