contrast media 1
DESCRIPTION
Contrast media 1. Radiographic Contrast Media. RAD TECH 255 SPECIAL PROCEDURES MERRILLS VOL2 RTA BOOK CH 19. Subject Contrast. Range of differences in the intensity of the x-ray beam, after it has been attenuated by the subject (patient). Low Subject Contrast . - PowerPoint PPT PresentationTRANSCRIPT
Contrast media 1
Radiographic Contrast Media
RAD TECH 255 SPECIAL PROCEDURES
MERRILLS VOL2RTA BOOK CH 19
Subject Contrast
• Range of differences in the intensity of the x-ray beam, after it has been attenuated by the subject (patient).
Low Subject Contrast
What can be done to attain medical information-
• see the difference between muscle, organs or vessels
Define and outline – organ structure and function
Contrast media
• Defines subtle differences in subject contrast
• Increases atomic number of area injected
• Results in a SHORTER scale of subject contrast
Purpose of Contrast Media
• To enhance subject contrast or render high subject contrast in a
tissue that normally has low subject contrast.
Atomic Number
• Fat = 6.46
• Water = 7.51
• Muscle = 7.64
• Bone = 12.31
Radiographic Contrast : Influenced by…
• Radiation Quality (KVP)
• Film Contrast
• Radiographic object (Patient)
KVP TYPE OF CONTRAST USED DETERMINES KVP RANGE•
BARIUM 90 – 120 kVp
IODINES 70 – 80 kVp(Ionic / Nonionic Water or Oil)
INJECTABLECONTRAST MEDIA
for RT 255 procedures
INVASIVE PROCEDURESThe “o-grams”
ALWAYS TAKE
A “SCOUT”
BEFORE CONTRAST INJECTION
√ PATHOLOGY
√ TECHNIQUE
√ PREP & PRIOR CONTRAST
√ POSITIONING
SPECIAL “o-grams”
• Venogram• Arthrogram• Sialogram• Myelogram• Arteriogram• Angiogram• Galactogram• Hystersalpingogram…….. etc
CONTRAST INJECTION
DOUBLE CONTRAST WITH IODINE - HIP Arthorgram
To check fertility
LYMPHANGIOGRAM
Galactography - Breast Duct
Cerebral Angiogram
SPECIAL PROCEDURESARE INVASIVE
ALWAYS GET PATIENT’S HISTORY AND CONSENT BEFORE
BEGINNING OR GIVING ANY CONTRAST
MEDIA
CONSENTS
• SIGNED AND WITNESSED• AFTER PROCEDURE HAS BEEN EXPLAINED• CHECK DEPARTMENT PROTOCOL• WHO’S RESPONSIBLE ??????
CONSENTS
• ASSAULT verbal threat of harm
• BATTERYUnlawful touching - unauthorized treatment“X-RAY” TAKEN ON WRONG PATIENT
• FALSE IMPRISONMENTRestraints require permission
from patient or authorized person
BLOOD WORK LAB TESTS to check function of kidneys prior to
injection of contrast • WATCH THE UPPER LIMITS• BUN = BLOOD UREA NITROGEN• Merrills pg 214 range is 8 to 25 pg 242 range is 10 - 20
always check with RAD when level above 20• CREATININE levels range:• pg 214 (0.6 - 1.5) pg 242 (0.05 - 1.2)
always check with RAD when level above 1.2 • Indicates function of kidneys • Diseases / dehydration / kidney failure
EGFR (new test)
• Estimated • Glomerular • Filtration • Rate
• More advanced test for • CREATININE levels
Review of Contrast Agents
Types of ContrastRoutes of AdminstrationChemical Components
Contrast Media changes the density of the organs
Therefore changing the Subject contrast will change the Radiographic contrast and film contrastMay need to INCREASE TECHNIQUE FROM SCOUT IMAGE
Contrast Media (review)
• Negative contrast• (AIR OR CO2)
• Radiolucent
• Low atomic # material
• Black on film
• Positive contrast • (all others)
• Radiopaque
• High atomic # material
• White on film
Types of Contrast Media
• Radiolucent-• negative contrast agent• x-rays easily penetrate • areas- appear dark on films
Negative Contrast Media• Air and gas
• complications• emboli-air pockets in
vessels• lack of oxygen
• Radiopaque- • positive contrast agent- • absorbs x-rays• appears light
Positive Contrast Agents• BARIUM • IODINES
Both + & - can be used in same study
2 BASIC TYPESOF CONTRAST material
• BARUIM Z# 56
• NON WATER SOLUABLE
• GI TRACT ONLY INGESTED OR RECTALLY• KVP 90 – 120*
• IODINE Z# 53• WATER SOLUABLE• POWDER• LIQUID• INTRAVENOUS OR• Intrathecal• GI TRACT• Also OIL based• KVP BELOW 90*
Methods of Administrationof Contrast Material
• INGESTED – (ORAL)
• RETROGRADE – AGAINST NORMAL FLOW
• INTRATHECAL – Spinal canal
• PARENTERAL (IV, Intrathecal)– Injecting into bloodstream– (anything other than oral)
Contrast media for SPECIAL PROCEDURES
Diagnostic agents that are injected into
• Circulatory System, Joint Spaces, Ducts
• Body orifices/organs: uterus, breast, salivary & lymph glands
BARIUM – a review
BARUIM SULFATENot used in Special Procedures
Barium Sulfate
• High atomic number• Not soluble in water• Used to coat the lining of organs• Supplied in different thicknesses• Used
– Esophogram, UGI, Small Bowel,Lower GI or BE
Ba ADVERSE REACTIONS
• BARIUM INERT• SUSPENSION MAY CAUSE ALLERGY• OCG TABLETS (IODINE) ALLERGY• AFTER EXAM – MAY SOLIDIFY DIFFICULT TO
EVACUATE• INCREASE FLUIDS, MILD LAXATIVE
• EXTRAVASATION OF CONTRAST INTO PERITONEUM
Extravasation of BA in abd
Ingested CONTRASTGastrografin or Hypaque
• High atomic #– Close to iodine
• Water soluble
• Similar usage as Barium
GASTROGRAFINAdverse Reactions
• Water soluble, safe in the abdominal cavity–Safe to use if perforation is suspected
• Very harmful to the lung tissue–Do not use if aspiration is possible
Gastro – Pathology present
• Bowel • Obstruction
• Note contrast• Seen in
kidneys as well
IODINEIONIC OR NON IONIC
WATER OR OIL BASE
IODINATED CONTRASTiodine z # 53
• WATER BASED
• INJECTED• VESSELLS/DUCTS• INGESTED• Organ function/flow• OPEN WOUNDS
• OIL BASED• INJECTED• NEVER VESSELLS• ONLY DUCTS• NOT INGESTED• OPEN WOUNDS
INJECTION OF IODINEinto Vessels
• ALWAYS A WATER BASED IODINATED COMPOUND
• BOLUS INJECTION• INFUSION DRIP
• IONIC VS• NON IONIC• CONTRAST
• 50 -70 % CONCENTRATE
IODINE WATER BASED CONTRAST
• IONIC• LESS $$$
• MORE REACTIONS
• NON IONIC• MORE $$$
• LESS REACTIONS
CONTRAST MEDIAIODINE
is either: IONIC or NON-IONIC • Osmolarity• # Of Particles (Cations + And Anions -)
– In Solution Per Kilogram Of Water• High Osmolarity
– =more Cations And Anions• Can Upset Homeostasis• Nonionic Have No Charged Particles
Contrast AgentsIONIC• High Osmolality
(Higher risk of complications)
– Diatrizoate sodium (Hypaque)
– Iothalamate meglumine (Conray)
NON-IONIC• Low Osmolality
(Lower risk of complications)
• Gadodiamide (Omniscan) – Iodixanol (Visipaque) – Iopamidol (Isovue) – Iopromide (Ultravist) – Ioversol (Optiray)
• Less money• More reactions
• More money• Less reactions
OIL – BASED
IODINECONTAST
Instilled in ORGAN
Oil Based Iodine• Fatty Acids• Insoluble in water
– White on the radiograph = Radiopaque• Uses
– Broncography (lungs)– Tear ducts– Salivary glands– Lymphatic system– Hysterrosalpingogram– Galactography (breast ducts)
• FAT EMBOLUS IF IT GETS INTO • BLOOD VESSEL
Newer Contrast Agents Balance Safety and Visualization