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Radiographic Contrast Media. RAD TECH 255 SPECIAL PROCEDURES WEBPAGE VERSION MERRILLS VOL2 RTA BOOK REV: SPRING 2010. Subject Contrast. Range of differences in the intensity of the x-ray beam, after it has been attenuated by the subject (patient). For LOW CONTRAST stucures:
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RadiographicContrast Media RAD TECH 255 SPECIAL PROCEDURES • WEBPAGE VERSION MERRILLS VOL2 RTA BOOK REV: SPRING 2010
Subject Contrast • Range of differences in the intensity of the x-ray beam, after it has been attenuated by the subject (patient). • For LOW CONTRAST stucures: • 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 used to: • enhance subject contrast or render high subject contrast in a tissue that normally has low subject contrast
Contrast media • Defines subtle differences in subject contrast • Increases atomic number of area injected • Results in a SHORTER scale of subject contrast
Radiographic Contrast : Influenced by… • Radiation Quality (KVP) • Film Contrast • Radiographic object (Patient) Atomic Number • Fat = 6.46 • Water = 7.51 • Muscle = 7.64 • Bone = 12.31
KVPTYPE OF CONTRAST USED DETERMINES KVP RANGE BARIUM _______kVp IODINES ________kVp (Ionic / Nonionic Water or Oil)
INJECTABLECONTRAST MEDIAfor RT 255 procedures INVASIVE PROCEDURES The “o-grams”
ALWAYS TAKE A “SCOUT” BEFORE CONTRAST INJECTION Why? List 4 reasons
SPECIAL “o-grams” • Venogram • Arthrogram • Sialogram • Myelogram • Arteriogram • Angiogram • Galactogram • Hystersalpingogram…….. etc
CONTRAST INJECTION KNEE ARTHROGRAM
Myelogram Contrast • Pantopaque was introduced in 1944 as a oil contrast medium • The first low-osmolar contrast medium to be produced was metrizamide (Amipaque) • Oil never completely re –absorbed • (Pre-employment L.sp)
LYMPHANGIOGRAM Now largely replaced by ________ ?
Dacryocystography Now largely replaced by CT
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 • BATTERY Unlawful touching - unauthorized treatment “X-RAY” TAKEN ON WRONG PATIENT • FALSE IMPRISONMENT Restraints require permission from patient or authorized person
The ARRT has a published code of ethics. • The ARRT Code of Ethics provides the radiologic technologist with an operational blueprint of norms of professional conduct.
Review of Ethics(Pt Care Book –Professional Ethics) The science of rightness and wrongness of human conduct and character is termed ethics. • __________is the ethical principle that means that “above all, do no harm.” • _________ principle that means that being truthful is right. • __________ is the ethical principle that means that actions benefit others.
Review of Contrast Agents Types of Contrast Routes of Adminstration Chemical Components
Contrast Media changes the density of the organs Therefore changing the Subject contrast will change the Radiographic contrast and film contrast May need to INCREASE TECHNIQUE FROM SCOUT IMAGE* f/s
Negative contrast (AIR OR CO2) Radiolucent Low atomic # material Black on film Positive contrast (all others) Radiopaque High atomic # material White on film Contrast Media (review)
Radiolucent- negative contrast agent x-rays easily penetrate areas- appear ____ on films Negative Contrast Media Air and gas complications emboli-air pockets in vessels lack of oxygen Radiopaque- positive contrast agent- absorbs x-rays areas- appear ____ on films Positive Contrast Agents BARIUM IODINES Both + & - can be used in same study Types of Contrast Media
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* 2 BASIC TYPESOF CONTRAST material
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
BLOOD WORKLAB 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 • Why is this important?
various water-soluble contrast media for urography and angiography • Both ionic and non-ionic monomers* • are all extracellular contrast media • are excreted unmetabolized by glomerular filtration • Approximately 85-90% of the injected dose is found in urine within the first 6 hours • 95-100% within the first 24 hours
monomers* • The ionic monomeric agents are salts that • dissociate into two molecules • one anion containing the radiopaque property due to three iodine atoms • and one cation without radiopaque properties • More on this later in the lecture…..
BARIUM – a review BARUIM SULFATE Not used in Special Procedures
Barium Sulfate • High atomic number Z #? ______ • 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
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
Bowel Obstruction Note contrast Seen in kidneys as well Gastro – Pathology present
IODINEIONIC OR NON IONIC WATER OR OIL BASE
WATER BASED INJECTED VESSELLS/DUCTS INGESTED Organ function/flow OPEN WOUNDS OIL BASED INJECTED NEVER VESSELLS ONLY DUCTS NOT INGESTED OPEN WOUNDS IODINATED CONTRASTiodine z # 53
ALWAYS A WATER BASED IODINATED COMPOUND BOLUS INJECTION INFUSION DRIP IONIC VS NON IONIC CONTRAST 50 -70 % CONCENTRATE INJECTION OF IODINEinto Vessels
IONIC LESS $$$ MORE REACTIONS NON IONIC MORE $$$ LESS REACTIONS IODINE WATER BASED CONTRAST
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
IONIC 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) Contrast Agents
Less money More reactions More money Less reactions
OIL – BASED IODINE CONTAST Instilled in ORGAN – Not vessells Oil-based iodine contrast media are made from fatty acids of poppy seed oil containing 48% and 37% iodine