answers for image interpretation sessionconplus.co.kr/~kcr2012/down/image_interpretation.pdf5....

Answers forImage Interpretation Session


































● Moderator Hyo-Keun Lim Samsung Medical Center

● Discussers AB Hun Kyu RyeomKyungpook National University Hospital

CH Hwan Seok YongKorea University Guro Hospital

GU Hak Jong LeeSeoul National University Bundang Hospital

NR Dae Seob ChoiGyeongsang National University Hospital

PD Choon Sik YoonGangnam Severance Hospital

October 18 (Thu), 14:00 - 15:30Grand Ballroom 101 - 105, Convention Hall 1F, Coex

KCR 2012

Image Interpretation Session 1

Case 1: Pediatric

Discusser Choon-Sik YoonCountry Republic of KoreaCurrent Affiliation Gangnam Severance Hospital

Age/Gender 5/FChief complaint Epigastric pain (10 months)

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Image Interpretation Session

2 KCR 2012

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Case 1

HistoryA 5-year-old girl presented with epigastric pain

for 10 months. Laboratory findings were withinnormal range.

FindingsPlain radiograph of the abdomen shows abnor-

mal amorphous calcification in the left upper ab-domen.

Contrast-enhanced abdominal CT scan demon-strates a well-defined, lobulated mass with hetero-geneous enhancement in the gastric high body.The mass shows dense calcification and endolumi-nal growth pattern.

An oblique view obtained after barium swallow-ing shows a smoothly marginated filling defectcontaining calcification, that forms obtuse angleswith the gastric wall suggesting a submucosalmass. Ulceration was not demonstrated.

Endoscopic examination of the stomach reveals apolypoid mass covered by normal-appearing mu-cosa at the anterior wall of gastric high body.

Differential DiagnosisGISTHamartomaTeratomaCarcinoid tumor

Diagnosis: Gastric inflammatory myofibroblastictumor

DiscussionGastric inflammatory myofibroblastic tumors

(IMT) are rare benign lesions that most often affectyoung adults and children. The tumor predomi-nantly affects females (ratio, 4:1) between the agesof 4 months and 15 years (mean age, 7 years). IMT

is a benign solid tumor composed mainly of spin-dle-shaped cells and has a chronic inflammatorycomponent consisting of plasma cells, lympho-cytes, and occasionally histiocytes. This lesion maynot be differentiated from malignant tumors radio-logically because of its local invasiveness and thetendency to recur. Additionally, some reported themalignant transformation of IMT and lymphoretic-ular malignancy arising in the residual IMT.

The clinical presentation of an IMT can vary anddepends on the site of origin. Symptoms includeweight loss, fever, and a general constellation of in-flammatory biomarkers such as anemia, thrombo-cytosis, elevated ESR, and hypergammaglobuline-mia. The clinical and laboratory abnormalities typ-ically resolve after surgical resection but can be as-sociated with local recurrence of the tumor. The ra-diologic findings of intraabdominal IMT are non-specific. It may show solid, sometimes heteroge-neous, well-demarcated (or multilobulated) spheri-cal mass. They may show infiltrative feature of theIMT as occurred in some cases.

The current treatment for a gastric IMT is com-plete surgical resection, with chemotherapy play-ing a role before surgery if complete excision is notpossible.

References1. Kamak I, Senocak ME, Ciffci AO, Caqlar M, Binqol-Kologlu

M, Tanyel FC, et al. Inflammatory myofibroblastic tumorin children: diagnosis and treatment. J Pediatr Surg2001;36:908-12

2. Kim KA, Park CM, Lee JH, Cha SH, Park SW, Hong SJ, etal. Inflammatory myofibroblastic tumor of the stomachwith peritoneal dissemination in a young adult: imagingfindings. Abdom Imaging 2004;29:9-11

3. Al Hatlani M, Ratcliffe EM. Endoscopic visualization of agastric polypoid mass: a rare pediatric presentation of an in-flammatory myofibroblastic tumor. Gastrointest Endosc.2010;72:894-5


4 KCR 2012

Case 2: Neuro

Discusser Dae Seob ChoiCountry Republic of KoreaCurrent Affiliation Gyeongsang National University Hospital

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Age/Gender 57/FChief complaint Headace (onset: a month ago)


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Case 2

HistoryA 56-year-old female presented with headache

and dizziness for a month. Recently, a right hemi-anopsia was accompanied.

FindingsAxial T2 FLAIR images show slightly hyperin-

tense mass with severe perilesional edema in theleft occipital lobe. The mass shows well-definedmargin and mixed signal intensity with heteroge-neous iso- or hypointense wall on T2WI, whichshows no calcification nor hemorrhage on gradientecho image. T1WI shows central mixed iso- andhyperintense portion and hyperintense rim. Aftercontrast material injection, smooth ring enhance-ment is seen. DWI shows restricted diffusion inthe center. The capsule shows no contrast en-hancement on rCBV map compatible with the hy-poperfusion (hypovascularization).

Differential DiagnosisPyogenic abscessMetastasisTuberculoma

Diagnosis: Tuberculoma

DiscussionInvolvement of the CNS is seen in approximately

5% of patients with tuberculosis. CNS tuberculosisusually results from hematogenous spread.However, it may result from direct rupture or ex-tension of a subependymal or subpial focus (Richfocus) and may be located in the meninges, brain,or spinal cord. CNS tuberculosis can manifest in avariety of forms, including tuberculous meningitis,tuberculomas, tuberculous abscesses, tuberculouscerebritis, and miliary tuberculosis.

The most common CNS parenchymal lesion oftuberculosis is tuberculoma (tuberculous granulo-ma). This lesion may be solitary, multiple, or mil-iary and may be seen anywhere within the brainparenchyma, although it most commonly occurswithin the frontal and parietal lobes.

The MRI findings depend on whether the tuber-culoma is caseating, and if so, whether the center

is liquid or solid. A noncaseating tuberculoma ishypointense relative to gray matter on T1WI andhyperintense on T2WI, with homogeneousgadolinium enhancement. Caseating tuberculomaswith a solid center are iso- to hypointense on bothT1- and T2WI. They usually have a variableamount of surrounding edema, which is hyperin-tense on T2WI. Caseating tuberculomas with a liq-uid center are hypointense on T1WI and centrallyhyperintense on T2WI, with a peripheral hy-pointense rim on T2WI representing the capsule.

Histologic correlation revealed that the centraliso- or hyperintensity on T1WI corresponded tocaseation necrosis with adjacent inflammatory in-filtrates. Surrounding slight hyperintense and hy-pointense rims corresponded to a layer of collage-nous fibrosis and a layer of outer inflammatory in-filtrates, respectively. The variable signal intensityof central caseation necrosis might be related to thevariable protein concentration which has varied T1relaxation time. Rim enhancement is usually seenat gadolinium-enhanced MRI. The core of the le-sion showed restricted diffusion similar to pyo-genic abscess. However, the ADC values weremuch lower than necrotic neoplastic lesions, be-cause of the high viscousity in the caseation necro-sis resulting from the presence of intact inflamma-tory cells. The low rCBV on perfusion-weightedimage is attributed to the high amounts of maturecollagen and decreased neovascularity. The rCBVratios in the capsular portions of brain abscesseswere significantly lower than those of malignanttumors compared with normal white matter.

References1. Burrill J, Williams CJ, Bain G, Conder G, Hine AL, Misra

RR. Tuberculosis: a radiologic review. Radiographics2007;27:1255-1273

2. Kim TK, Chang KH, Kim CJ, Goo JM, Kook MC, Han MH.Intracranial tuberculoma: comparison of MR with patho-logic findings. AJNR Am J Neuroradiol 1995;16:1903-1908

3. Castillo M, Mukherji SK. Diffusion-weighted imaging in theevaluation of intracranial lesions. Semin Ultrasound CTMR 2000;21:405-416

4. Holmes TM, Petrella JR, Provenzale JM. Distinction be-tween cerebral abscesses and high-grade neoplasms by dy-namic susceptibility contrast perfusion MRI. AJR Am JRoentgenol 2004;183:1247-1252

5. Erdogan C, Hakyemez B, Yildirim N, Parlak M. Brain ab-scess and cystic brain tumor: discrimination with dynamicsusceptibility contrast perfusion-weighted MRI. J ComputAssist Tomogr 2005;29:663-667

6 KCR 2012


Case 3: Chest

Discusser Hwan Seok YongCountry Republic of KoreaCurrent Affiliation Korea University Guro Hospital

Age/Gender 16/MChief complaint Chronic productive cough, mild dyspnea

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Case 3

History A 16-year old male presented with chronic pro-

ductive cough and mild dyspnea.

FindingsInitial chest radiography revealed diffusely in-

creased interstitial markings in both lungs.High-resolution CT scan showed bilateral sym-

metric diffuse bronchiectasis and bronchiolitiswith mucoid plugging in both lungs, which wasmore prominent in upper and mid-lung zones.

Differential DiagnosisDiseases that can manifest diffuse bronchiectasis

and bronchiolitis include:�Diffuse panbronchiolitis (DPB)�Ciliary dyskinesia (immotile cilia syndrome)�Allergic bronchopulmonary aspergillosis (AB-

PA)�Non-tuberculous mycobacterial infection

(NTM disease)�Cystic fibrosis (CF)

Lab. Findings�Sweat chloride test (+)�CFTR gene mutation (+)

Pathologic DiagnosisExplantation and transplantation of bilateral

lungs was performed 8 years after the first visit.Pathologic examination of resected specimensshowed:

1) diffuse bronchiolar dilatation with acute in-flammation and luminal purulent material,

2) dense peribronchiolar fibrosis and honeycombchange.

Diagnosis: Cystic fibrosis

Discussion Cystic fibrosis is one of most common inherited

diseases in the Western world (autosomal reces-

sive, 1/2,000-3,500 live births), but it is very rare innonwhites (only 6 cases in Korea). It is known to beresulted from CFTR (CF transmembrane conduc-tance regulator) gene mutation, which causes ab-normal mucus formation in the airway, leading toluminal obstruction and recurrent bronchial in-flammation and infection. Thus, the involved lungsshow diffuse bronchiectasis, bronchiolitis and mu-coid plugging. Although the major clinical manifes-tation of cystic fibrosis is an obstructive pulmonarydisease (almost 100%) with recurrent bacterial res-piratory infections, the incidence of pancreatic in-sufficiency (80-90%) is also highly reported. Thediagnosis of cystic fibrosis is confirmed by a sweatchloride test (standard) ( 60 mmol/L) and CFTRgene mutation ( 2 among 1,500 types). Thetreatment includes antibiotics and anti-inflamma-tory agents for conservative purposes. Regardingthe prognosis of cystic fibrosis, 80% of patientsreach adulthood with a median survival 40years.

HRCT findings include:�Bronchiectasis (100%): bilateral symmetric,

more severe in the upper lobes�Bronchial wall thickening, mucus plugging�Consolidation or atelectasis (80%)�Cystic/bullous lesions:

subpleural regions of upper lobes�Branching centrilobular nodules (a tree-in-bud

pattern) as an early sign of disease�Air trapping on expiratory CT.

References1. Kim SJ, Lee M, Cha SI, et al. Standardized Sweat Chloride

Analysis for the Diagnosis of Cystic Fibrosis in Korea.Korean J Lab Med 2008;28:274-281

2. Farrell PM, Rosenstein BJ, White TB, et al. Guidelines fordiagnosis of cystic fibrosis in newborns through olderadults: Cystic Fibrosis Foundation consensus report. JPediatr 2008;153:S4-S14

3. Muller NL, Silva CIS. Specific causes of bronchiectasis. In:Imaging of the chest, Vol.2, Saunders, Philadelphia.2008;1039-1055

8 KCR 2012


Case 4: Gastrointestinal

Discusser Hun Kyu RyeomCountry Republic of KoreaCurrent Affiliation Kyungpook National University Hospital

Age/Gender 70/MChief complaint Intrahepatic mass on follow-up CT

(Hx. s/p Abdominoperineal resection for sigmoid colon cancer, 5 years ago)

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Case 4

HistoryA 70-year-old male presented with recently

found abdominal mass on F/U CT who underwentabdominoperineal resection for sigmoid colon can-cer 5 years ago.

FindingsRecent abdominal CT reveals a 3.1 cm mass

showing lobulating margin and heterogeneous en-hancement with central low density portion sur-rounded by a low-density rim.

On MRI, the mass shows hypo intensity onT1WI, high signal intensity on T2WI, and defecton hepatobiliary phase. Gadoxetic acid-enhanceddynamic images show arterial hypervascularityand heterogeneous enhancement with washoutportion on portal venous phase. Central scarshowed hypointensity on T1WI, hyperintentensityon T2WI, and gradual enhancement.

Differential DiagnosisMetastasis from colon cancerCholangiocarcinomaScirrhous HCCCombined hepatocellular and

cholangiocarcinoma

Diagnosis: Scirrhous HCC with a central scar andscalloped margin

DiscussionAccording to WHO classification, scirrhous HCC

is a subtype of HCC characterized by diffuse fibro-sis along the sinusoid-like blood spaces and atro-phy of tumor trabeculae. Radiological findings ofscirrhous HCC include homogenous architecture,peripheral rim-like enhancement on arterial phase,followed by prolonged and delayed enhancementon equilibrium phase, absence of tumor capsule,and a retraction of the liver surface. Scirrhous HCCis often misdiagnosed as cholangiocarcinoma,metastasis, and combined hepatocellular andcholangiocarcinoma because of heterogenous en-hancement in the arterial phase and prolonged en-hancement in the late phase attributed to abundant

fibrous stroma.There was a report that scirrhous HCC included

two types: 1) one with dense fibrosis as in cholan-giocarcinoma; and 2) one with a central scar withlamellar fibrosis as in fibrolamellar HCC. The sec-ond type might be the same as scalloped HCC inthe present case.

On histology, there is a central scar consisting ofcoarse fibrosis and lamellar or dense fibrous bandsdividing the tumors into small parts in varioussizes. These tumor cells do not show oncocyte-likefeatures such as in fibrolamellar HCC. Fibrousbands are connected from the central scar to theperipheral margin of the tumor, so scalloped HCChas a lobulated tumor margin without distinct cap-sule formation.

Scirrhous HCC with a central scar and scallopedmargin tends to appear in patients with non-cir-rhotic liver and a lower serum level of AFP com-pared to usual HCC; therefore, it is difficult to dif-ferentiate from cholangiocarcinoma, fibrolamellarHCC or FNH in some cases.

The recurrence rates of scalloped HCC are notdifferent from those of simple nodular HCC.However, the time of recurrence is later, and the 5-and 10-year survival rates are better in patientswith scalloped HCC than in patients with simplenodular HCC.

References1. Lee JH, Choi MS, Gwak GY, et al. Clinicopathologic char-

acteristics and long-term prognosis of scirrhous hepatocel-lular carcinoma. Dig. Dis. Sci. 2012;57:1698-1707

2. Kim SH, Lim HK, Lee WJ, et al. Scirrhous hepatocellularcarcinoma: comparison with usual hepatocellular carcino-ma based on CT-pathologic features and long-term resultsafter curative resection. Eur. J. Radiol. 2009;69:123-130

3. Leon TY, Kim SH, Lee WJ, et al. The value of gadobenatedimeglumine-enhanced hepatobiliary-phase MR imagingfor the differentiation of scirrhous hepatocellular carcino-ma and cholangiocarcinoma with or without hepatocellularcarcinoma. Abdom Imaging 2010;35:337-345

4. Yamamoto M, Ariizumi S, Yoshitoshi K, et al.Hepatocellular carcinoma with a central scar and a scal-loped tumor margin resembling focal nodular hyperplasiain macroscopic appearance. J. Surg. Oncol. 2006;94:587-591


12 KCR 2012

Case 5: Genitourinary

Discusser Hak Jong LeeCountry Republic of KoreaCurrent Affiliation Seoul National University Bundang Hospital

Age/Gender 43/FChief complaint Abdominal pain (1 month ago)

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Case 5

History A 43-year-old female presented with lower ab-

dominal pain for one month.

FindingsOutside US images depicted multiseptated cystic

lesions combined with a large unilocular cystic le-sion in the pelvic cavity. On CT images, there wereseveral multiseptated and unilocular cystic masseswith or without ascites in the lower abdomen andpelvis. Both ovarian tissues were located withinthose cystic lesions. No enhancing solid portionwithin the cystic mass was seen. MR images alsodemonstrated similar findings with those of CT im-ages. On both T1- and T2WI showed multiseptatedcystic masses around the uterus, while the uterus,fallopian tubes, and both ovaries look normal inshape except several small intramural leiomyomasin the uterus. In addition, CT images showed twolobulated cystic lesions with peripheral rim en-hancement in the portocaval space and perihepaticspace, respectively. A focal scalloping without theparenchymal invasion was noted at the hepaticparenchyma adjacent to the perihepatic lesion.

Differential DiagnosisTuberculous peritonitisPrimary ovarian epithelial tumor with peritoneal

seedingPeritoneal seeding with unknown primary

Diagnosis: Tuberculous peritonitis

DiscussionGenital tract involvement was detected in 1.3%

of female patients with tuberculosis, and the affect-ed sites were the endometrium (72%), salpinx(34%), ovary (13%), and cervix (2%). Tubo-ovarianinvolvement is usually caused by hematogenous orlymphatic spread and occasionally by peritonealdissemination. It can mimic ovarian cancer byboth radiologic and clinical findings; the symptomsare usually vague, serum CA-125 levels are usuallyelevated, and the radiologic findings closely resem-ble those of ovarian cancer with peritoneal seed-ing. Therefore, the definite diagnosis is usually

made postoperatively.When overt tubo-ovarian abscesses (TOA) are

formed by tuberculosis, complex adnexal masseswith a large amount of ascites may be demonstrat-ed on US, resembling ovarian malignancies withperitoneal seeding. When ovaries and salpinges areaffected by peritoneal tuberculosis, tubo-ovarianlesions are usually minimal or even inconspicuouson CT, whereas the findings of tuberculous peri-tonitis frequently mimic those of peritoneal carci-nomatosis. MRI is more helpful in revealing tubo-ovarian lesions and may demonstrate thickenedsalpinges or nodularities along tubo-ovarian sur-faces. However, these findings are also nonspecificand differentiation from peritoneal seeding or pri-mary ovarian malignancy such as serous surfacepapillary carcinomas is difficult. Some helpfulfindings suggestive of tuberculous peritonitis aresmoother peritoneal thickening at CT and a moreregular pattern of small nodularities along the peri-toneum on MRI. Calcifications may be found inadnexal masses on CT and suggest tuberculosis butare not frequently observed, especially in active in-flammation. Lymph node enlargement is common,and necrotic lymph nodes suggesting tuberculouslymphadenitis may be found.

On MRI, the walls of tuberculous TOAs are oftenirregular and show hypointensity on T2WI.Compared with usual TOAs, in which the wallthickening is usually uniform, tuberculous TOAmay show a serrated or nodular inner wall. Denseadhesion with the uterus or other adjacent organsis common and reflects a late fibrotic process ofthis infection.

References1. Kim SH, Yang DM, Kim KA. Unusual causes of tubo-ovari-

an abscess: CT and MR imaging findings. Radiographics2004;24:1575-1589

2. Crowley JJ, Ramji FG, Amundson GM. Genital tract tuber-culosis with peritoneal involvement: MR appearance.Abdom Imaging 1997;22:445-447

3. Rodriguez E, Pombo F. Peritoneal tuberculosis versus peri-toneal carcinomatosis: distinction based on CT findings. JComput Assist Tomogr 1996;20:269-272

4. Barutcu O, Erel HE, Saygili E, Yildirim T, Torun D.Abdominopelvic tuberculosis simulating disseminatedovarian carcinoma with elevated CA-125 level: report oftwo cases. Abdom Imaging 2002;27:465-470


14 KCR 2012

Case 6: Pediatric

Discusser Choon-Sik YoonCountry Republic of KoreaCurrent Affiliation Gangnam Severance Hospital

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B (T2WI) C (STIR)

Age/Gender 16/FChief complaint Multiple bony masses, P/Hx Right humerus fracture (10 months ago)


D (T1WI) E (T1WI)

F G H

Case 6

History A 16-year-old girl presented with progressive left

hip pain for 8 months. She had an episode of righthumerus fracture 10 months age without history oftrauma. Laboratory exam. showed an elevatedserum calcium level of 11.9 mEq/l (normal 4.2-5.2mEq/l) and serum intact parathyroid hormone(iPTH) level of 2091 pg/ml (normal 15-50 pg/ml).

FindingsAnteroposterior radiograph of the pelvis, lateral

radiograph of the femur and anteroposterior radi-ograph show multifocal expansile osteolytic lesionsinvolving bilateral pelvic bones and proximal fe-murs.

On MRI, the lesions have solid and cystic compo-nents. The solid components show hypointensityon T1WI and heterogeneous intermediate to hy-pointensity on T2WI. Multifocal cystic areas showfluid-fluid levels on T2WI. Neither reactive edemaof adjacent bone marrow nor soft tissue is seen.

10 months age when the patient had an episodeof right humerus fracture, radiograph showed anexpansile osteolytic lesion with pathologic fracture.Note that several small osteolytic lesions and sub-periosteal bone resorption at the right humeralhead and scapula. On T1WI, the lesion revealed aseptated cystic lesion with fluid-fluid level. Aftercontrast material injection, the septa of the cysticlesion and adjacent muscles were enhanced.

Whole body bone 99mTc-MDP scintigraphyshowed multiple foci of increased uptake on theskull, maxilla, mandible, both humerus, right ulna,both ribs, vertebrae, pelvic bones, femurs, and tib-ias.

A solitary adenoma of the left lower parathyroidgland was identified by 99mTc-methoxyisobutyl-isonitrile (MIBI) scintigraphy and US scan.

Differential DiagnosisLangerhans cell histiocytosisGiant cell tumors with ABC change Fibrous dysplasia with ABC formationOsteolytic metastasesBone cysts

Diagnosis: Brown tumor with primary hyper-parathyroidism

Discussion Brown tumors are nonneoplastic, osteolytic le-

sion of the bone caused by primary or secondaryhyperparathyroidism. It can occur as solitary ormultiple lesions in any bone, but commonly affectsthe pelvis, ribs, femur, other long bones, facialbones, metacarpals, phalanges, clavicle, spine, andrarely the sphenoid sinus.

The name of brown tumor arises from its grosslybrownish color on biopsy due to the rich vasculari-ty, hemorrhage, and hemosiderin deposition.Histopathologically it is characterized by hypervas-cular fibroblastic stroma, foci of hemorrhage, andaccumulation of osteoclastic multinucleated giantcells.

Radiographically, brown tumors are seen as ex-pansile lytic lesions. The cortex may be thinned orfractured. Other imaging findings of hyperparathy-roidism can be associated with brown tumor in-cluding osteopenia, subperiosteal bone resoption,and pathologic fracture. On MRI, they are single ormultifocal lesions of a cystic nature mixed with orwithout solid lesions. The solid portions are iso tohypointense on the T1- and T2WI and the cysticportions are hyperintense on the T2WI. The solidportions and the septa of the cystic portions arewell enhanced. Cortical destruction and soft-tissueextension can be seen.

References1. Hong WS, Sung MS, Chun KA, Kim JY, Park SW,

Lee KH, et al. Emphasis on the MR imaging findingsof brown tumor: a report of five cases. SkeletalRadiol 2011;40:205-13

2. Takeshita T, Takeshita K, Abe S, Takami H,Imamura T, Furui S. Brown tumor with fluid-fluidlevels in a patient with primary hyperparathy-roidism: radiological findings. Radiat Med 2006;24:631-634

3. Miyakoshi M, Kamoi K, Takano T, Nishihara M,Kawashima T, Sudo N, et al. Multiple brown tumorsin primary hyperparathyroidism caused by an ade-noma mimicking metastatic bone disease with falsepositive results on computed tomography and Tc-99m sestamibi imaging: MR findings. Endocr J 2007;54:205-210

16 KCR 2012


Case 7: Neuro

Discusser Dae Seob ChoiCountry Republic of KoreaCurrent Affiliation Gyeongsang National University Hospital

Age/Gender 25/FChief complaint Left-side weakness and paresthesia

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Case 7

HistoryA 25-year-old female presented with left side

weakness and hyperesthesia in her body and facefor a week with nausea, vomiting, dizziness and fa-tigue.

FindingsMultiple cortical or subcortical lesions are pre-

sent in bilateral frontal lobe, left mediobasal tem-poral lobe and left medulla oblongata. On T2WI,there is a peri-lesional edema. On T1WI, focal hy-perintenstiy, which is suspected as a hemorrhagiccomponent, is present in the largest lesion in theleft frontal lobe. Gradient echo images confirm theexistence of internal hemorrhagic components inall lesions. These lesions show thick and irregularperipheral rim enhancement on contrast enhance-ment study and non-enhancing foci are consideredto be a necrotic component.

On DWI, the largest lesion in the left frontal lobeshows diffusion restrictive component, which isconsidered to be cystic areas consistent with necro-sis. Perfusion weighted images reveal that a lack ofrCBV increment in all lesions.

Differential DiagnosisPrimary CNS lymphoma Metastases

Diagnosis: Primary CNS T-cell lymphoma

DiscussionIn general, CNS T-cell lymphoma (T-PCNSL) is

more prevalent in Eastern countries, of which theincidence was 16.7% in Korea.

In Eastern countries, T-PCNSL is more likely tobe located in either the supratentorial or subcorti-cal areas.

Necrosis and hemorrhage are more often notedin the PCNSL of immunocompromised patientsand are scarce in immunocompetent patients. AndT-PCNSL showed necrosis more frequently thanCNS B-cell lymphoma (B-PCNSL). Some T-PCNSLsshowed high and low signal intensity on the DWI

and ADC map, respectively, as well as finding ofcystic areas consistent with necrosis, which raisesthe possibility of an abscess.

Homogeneous enhancement has generally beenconsidered to be a characteristic finding of PCNSL,but the T-PCNSL showed rim enhancement or het-erogeneous enhancement, which is dissimilar tothe enhancement pattern of B-PCNSL. T-PCNSLmostly consists of small-sized cells which are inter-spersed without forming a solid mass, while B-PC-NSL is commonly composed of large cells thatcrowd together to form monomorphous sheets.These different pathologic manifestations may giverise to their distinct enhancement patterns: hetero-geneous enhancement in T-PCNSL and homoge-neous enhancement in B-PCNSL.

On perfusion-weighted imaging, it was reportedthat neo-vascularization is not identified in PCNSL,in contrast to anaplastic gliomas. Thus, PWI can beused to differentiate cerebral lymphomas fromanaplastic gliomas. Nevertheless, further studiesshould be con-ducted to determine the usefulnessof PWI in differentiating T-PCNSL from high-gradegliomas.

References1. Choi JS, Nam DH, Ko YH, Seo JW, Choi YL, Suh YL,

et al. Primary central nervous system lymphoma inKorea: comparison of B- and T-cell lymphomas. Am JSurg Pathol 2003;27:919-28

2. Coulon A, Lafitte F, Hoang-Xuan K, Martin-Duverneuil N, Mokhtari K, Blustajn J, et al.Radiographic findings in 37 cases of primary CNSlymphoma in immunocompetent patients. EurRadiol 2002;12:329-40

3. Kim EY, Kim SS. Magnetic resonance findings of pri-mary central nervous system T-cell lymphoma in im-munocompetent patients. Acta Radiol 2005;46:187-192

4. Kleihues P, Burger PC, Scheithauer BW. Histologicaltyping of tumours of the centeral nervous system.Berlin: Springer Verlag; 1999

5. Hartmann M, Heiland S, Harting I, Tronnier VM,Sommer C, Ludwig R, et al. Distinguishing of prima-ry cerebral lymphoma from high-grade glioma withperfusion-weighted magnetic resonance imaging.Neurosci Lett 2003;338:119-22


20 KCR 2012

Case 8: Chest

Discusser Hwan Seok YongCountry Republic of KoreaCurrent Affiliation Korea University Guro Hospital

A

C D

B

Age/Gender 60/MChief complaint Abnormal chest radiograph

Case 8

HistoryA 60-year-old man presented with an abnormal

chest radiographic finding.

FindingsPlain chest radiograph showed diffusely in-

creased interstitial markings in both lower lungs.Chest HRCT scan showed diffuse interlobular sep-tal thickening and diffuse centrilobular micronod-ules plus subpleural nodules (so called, perilym-phatic nodules), which were more prominent inthe lower lung zones. Also, multiple punctate calci-fications are noted in the micronodules.

Differential DiagnosisDiseases that can manifest perilymphatic nod-

ules among diffuse micronodular lung diseases in-clude:

Sarcoidosis PneumoconiosisHematolymphangitic carcinomatosis Amyloidosis.

Diagnosis: Amyloidosis, primary, a diffuse intersti-tial form, involving gastrointestinal tracts andlungs, in a patient with multiple myeloma

Stomach biopsy performed due to hemateme-sis symptom: Amorphous material deposition in laminapropria; c/w amyloidosis Bone marrow biopsy: Plasma cell myeloma

DiscussionAmyloidosis is a constellation of disease entities

characterized by the abnormal extracellular depo-sition and accumulation of fibrillar protein andprotein derivatives. Primary amyloidosis is associ-ated with plasma cell dyscrasia, such as plasma

cell myeloma or MGUS, and secondary amyloido-sis can be seen in chronic inflammatory conditionsor tissue-destructive processes such as rheumatoidarthritis or inflammatory bowel diseases. It canmanifest either a systemic (80-90%) or a localized(10-20%) form.

Primary amyloidosis occurs in 5-12 persons/mil-lion per year, and 20% of them progress to multiplemyeloma. It can involve kidneys, heart, gastroin-testinal tracts, peripheral nerves, liver, and spleen.The respiratory system is also involved in 50%.The treatment of amyloidosis includes chemother-apy, ASCT, organ transplantation, and surgery.

Pulmonary amyloidosis manifests one of threeforms: tracheobronchial, nodular parenchymal,and diffuse interstitial form. The tracheobronchialpattern is most common, and manifests as focal ordiffuse thickening with luminal narrowing of thetracheobronchial wall.

The nodular parenchymal pattern shows a soli-tary or multiple well-defined nodules (amyloido-ma, 0.5-5 cm), which are located most commonlyin the lower lobes, showing calcification in 20%-50%. The diffuse interstitial pattern is least com-mon with a poor prognosis, usually seen in multi-ple myeloma. The HRCT shows widespread inter-lobular septal thickening, irregular lines, and dif-fuse perilymphatic micronodules with some punc-tate calcifications, which are more prominent inthe lower lungs.

References1. Pickford HA, Swensen SJ, Utz JP. Thoracic cross-sec-

tional imaging of amyloidosis. AJR Am J Roentgenol1997;168(2):351-355

2. Georgiades CS, Neyman EG, Barish MA, FishmanEK. Amyloidosis: review and CT manifestations.Radiographics 2004;24(2):405-416

3. Urban BA, Fishman EK, Goldman SM, et al. CT eval-uation of amyloidosis: spectrum of disease.Radiographics 1993;13(6):1295-1308


22 KCR 2012

Case 9: Abdomen

Discusser Hun Kyu RyeomCountry Republic of KoreaCurrent Affiliation Kyungpook National University Hospital

D (T2) E (T1)

B (Arterial) C (Portal)

A (EGD)

Age/Gender 68/FChief complaint Known EGC IIa+IIc in antrum on gastroscopy


I (DWI, b=800) J (ADC)

F (Arterial) G (Portal) H (Delay)

Case 9

HistoryA 68-year-old female diagnosed as early gastric

cancer (EGC) type IIa+IIc in the antrum on en-doscopy.

FindingsPreoperative contrast-enhanced CT scan re-

vealed no abnormality in the stomach and no evi-dence of distant metastasis. However, a 3.2 cmmass was detected around common hepatic arterywhich abutted the pancreas. It showed well-de-fined margin and relatively homogenous enhance-ment. Its degree of enhancement was less than ad-jacent pancreas parenchyma.

On MRI, the mass showed hypointensity onT1WI, hyperintensity on T2WI, and less contrastenhancement compared with the pancreas on dy-namic images. DWI revealed diffusion restriction.It was impossible to discriminate between intra-and extra pancreatic location of the mass even onMRI. Finally, US was performed to localize themass. It showed a sliding motion against the pan-creas during the patient s respiration.

Differential DiagnosisMetastatic lymph node from EGCExophytic pancreatic tumor

Neuroendocrine tumorSolid pseudopapillary tumor

Diagnosis: Metastatic lymph node from EGCSubtotal gastrectomy and regional lymphnode dissection: single metastatic lymph nodein the area of common hepatic artery(T1bN1).

DiscussionThe incidence of lymph node metastasis has

been reported to range from 2.6 to 4.8% in EGCpatients. While the prognosis for surgically treated

EGC is excellent, with 5-year survival greater than90%, patients with lymph node metastasis havelower survival rates than those without metastasis.The recurrence rate is higher in patients withlymph node metastasis than in patients withoutthat (7-20% vs. 0.6-0.7%).

Unlike the stationary imaging modality such asCT and MR, ultrasonography gives us the real timemonitoring of targeted lesion with some interven-tion such as respiratory movement. Based on thefact that intraperitoneal and retroperitoneal organsmove differently during respiration, we can ob-serve the same phenomenon demonstrated be-tween extra- and intra-pancreatic lesions, calledsonographic sliding sign.

In this case, sonographic sliding sign is a valuableclue in making a correct diagnosis differentiatingbetween a intra- and extra-pancreatic localizationwhen CT and MR has been inconclusive. Whenwe wonder if the origin of lesion is between intraand retro-peritoneal location, it could lead to limitthe differential diagnosis.

References1. Park CH, Song KY, Kim SN. Treatment results for gastric

cancer surgery: 12 years experience at a single institute inKorea. Eur J Surg Oncol 2008;34:36-41

2. Haruta H, Hosoya Y, Sakuma K, Shibusawa H, Satoh K,Yamamoto H, Tanaka A, et al. Clinicopathological study oflymph-node metastasis in 1,389 patients with early gastriccancer: assessment of indications for endoscopic resection.J Dig Dis 2008;9:213-218

3. Nam MJ, Oh SJ, Oh CA, Kim DH, Bae YS, Choi MG, NohJH, et al. Frequency and predictive factors of lymph nodemetastasis in mucosal cancer. J Gastric Cancer 2010;10:162-167

4. Lim HK, Kim S, Lim JH, Kim SH, Lee WJ, Chun H, ChoJW, et al. Assessment of pancreatic invasion in patientswith advanced gastric carcinoma: usefulness of the slidingsign on sonograms. AJR Am J Roentgenol 1999;172:615-618

5. Lim JH, Ko YT, Lee DH. Sonographic sliding sign in local-ization of right upper quadrant mass. JUM 1990;9:455-459

24 KCR 2012


Case 10: Genitourinary

Discusser Hak Jong LeeCountry Republic of KoreaCurrent Affiliation Seoul National University Bundang Hospital

Age/Gender 49/MChief complaint Right scrotal pain (2 months ago)

A B

C D

E F

Case 10

HistoryA 49-year-old male presented with right scrotal

pain for 2 months. Serum AFP and HCG levelswere within normal range.

FindingsThe US images depicted a 1.5 cm mass showing

heterogeneous echotexture in the right testis. Oncolor doppler images, the mass showed minimalvascularity. The origin of the lesion was not clearlydetermined because it abuts both the testis and epi-didymal tail. MRI demonstrates an exophytic massin the right testis showing isointensity on T1WIand heterogeneous hypointensity relative to thetesticular parenchyma on T2WI. The epididymislooks separated from the mass, and the massseems to be a paratesticular lesion. Contrast-en-hanced images were not obtained.

Differential DiagnosisEpidermoid cystNon-seminomatous germ cell tumorAbscessBenign tumor originating from tunica albuginea.

Diagnosis: Adenomatoid tumor originating fromtunica albuginea.

DiscussionAdenomatoid tumor is the most common parat-

esticular neoplasms and account for approximately30% of all paratesticular neoplasms. It occurs inmen with a wide range of ages, with the majorityin patients aged 20-50 years. Patients usually pre-sent with a painless scrotal mass. The tumors aresmooth, round, well-defined and vary in size from0.4-5.0 cm. Although more frequent in the tail,

adenomatoid tumor may occur anywhere in theepididymis and have also been reported in thespermatic cord, paratesticular tissue and tunica al-buginea, where they can grow intratesticularly.Thus these lesions can extend into the testis from aparatesticular location, and it may be necessary toobtain an MRI after an initial US to prove their ex-tratesticular origin.

The histologic nature of adenomatoid tumors hasbeen a source of controversy, with most investiga-tors suggesting a mesothelial origin. In female sub-jects, adenomatoid tumors are commonly found inthe uterus and fallopian tubes. Because of the be-nign nature of this tumor, the treatment of choiceis local excision.

On US, they appear nonspecific and variable, al-though the majority appears isoechoic and homo-geneous. When the epididymis is involved, it iseasily identified as extratesticular. When the lami-na parietalis of the tunica vaginalis is involved,they cannot be differentiated from peripheral tes-ticular tumors in the absence of fluid collection.

MRI demonstrates hypointensity relative to thetesticular parenchyma on T2WI. MRI can aid indetermining the paratesticular origin of the lesion.After contrast material injection, slow or decreasedenhancement relative to the normal testis may bedemonstrated and also suggest a benign condition.

References1. Park SB, Lee WC, Kim JK, et al. Imaging features of benign

solid testicular and paratesticular lesions. Eur Radiol2011;21:2226-2234

2. Akbar SA, Sayyed TA, Jafri SZH, Hasteh F, Neill JSA.Multimodality imaging of paratesticular neoplasms andtheir rare mimics. Radiographics 2003;23:1461-1476

3. Kim W, Rosen MA, Langer JE, Banner MP, Siegelman ES,Ramchandani P. US-MR Imaging correlation in pathologicconditions of the scrotum. Radiographics 2007;27

26 KCR 2012

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