RADIO ISOTOPE SCAN PRINCIPLES RADIO ACTIVE TRACER SUBSTANCE IS USED. COUPLED WITH SPECIFIC KITS FOR VARIOUS ORGANS. SENSITIVE AND SPECIFIC-PICKS PATHOLIGY AT EARLIEST. MINIMAL RADIATION.
PREPARATION No specific preparation for Bone scan & Renal scan Cardiac scan- to stop coffee, Chocolate, Ca channel blockers before two days, 6 hrs. fasting Thyroid scan – To stop Anti thyroid drugs before 2 weeks. Liver (Hida) scan – NB Phenobarb. for 1wk. To drink lot of water during the scanning. To void frequently during test period.
Indication of bone scan All first diagnosed malignancies. Ca. Breast, Cx & Uterus etc. Lung & Prostate cancers. Hodgkin’s lymphoma & other malign. Pathological Fractures. AVN & ? Pelvic girdle pain. Osteo mylitis. Stress fracture/ vague boney pain. Unexplained backache.
Indications Recurrent UTI & Growth retardation in children. GUT problems & unexplained Anemia. Primary Hyper tension. Renal donor evaluation Renal Transplant evaluation
Effect of Creatinine If level of S.Creatinine is high then extraction of Tc-99m –DTPA is low and delayed. Background is also very high. GFR is low. In this case it needs to be inject more activity. EC scan is recommended.
DMSA cortical imaging DMSA has tubular binding receptor. It binds with tubular protein for a longer period. Imaging is generally done after 3 hours delay to allow time for uptake and slow background clearance. NON-FUNCTIONING RT KIDNEY
Myocardial Perfusion scan (Stress Thallium) EASY & SAFE: NON-INVASIVE, OUT PATIENT PROCEDURE, NO DYE NO ALLERGY FUNCTIONAL IMAGING : SHOWS BLOOD FLOW & VIABILITY; NOT JUST THE MECHANICAL BLOCK TRUE FLOW PATTERN : REVEALS COLLATERALS & MICROVASCULAR CIRCULATION & CORONARY STEAL PHENOMENON VIABILITY: STUNNED MYOCARDIUM, HIBERNATING MYOCARDIUM MOST COMPREHENSIVE INVESTIGATION OFFERING MAXIMUM INFORMATION FROM SINGLE STUDY
PATIENT PREPARATION 6 Hrs. FASTING FOR THALLIUM IS ESSENTIAL. DISCONTINUATION OF BETA-BLOCKERS & FRUSEMIDE FOR 72-48 HRS BEFORE EXERCISE STRESS NO THEOPHYLLINE AND CAFFEINE BEFORE ADENOSINE STRESS NO NITRATES PREFERABLY ON THE DAY OF EXERCISE STRESS DETAILED HISTORY TAKING
INDICATIONS : EVALUATION OF CAD (Coronary Artery Disease): in cases with equivocal TMT/ECHO and/or chest pain, high risk group prior to non- cardiac surgery POST ANGIO PLASTY & POST CAG: CHRONIC H.T. SPLY. WITH D.M. CHEST PAIN & UNEXPLAINED DYSPNOEA.
MYOCARDIAL PERFUSION IMAGE Normal Vs Abnormal NORMAL ISCHEMIA. INFARCT