INVESTIGATIONS OF CHOICE [IOC] Diagnosis/ Disease Investigation of Choice All space occupying lesions MRI of brain Acute pancreatitis CT scan Acalculous cholecystitis HIDA scan Acoustic Neuroma Gd - enhanced MRI Anal fissure Local examination under LA Aneurysm Angiography Any paranasal sinus FESS Amyloidosis Abdominal fat biopsy/Rectal Biopsy + Congo red stain Any other condition of ear HRCT Aortic dissection Patient is stable – MRI Patient is unstable - TEE Any metastases/ Muscle/Soft tissue MRI Calculous cholecystitis USG Cardiotoxicity Following CT/RT - biopsy Cardiac tamponade ECHO Chronic subarachnoid Haemorrhage Flair MRI Congenital hypertrophic pyloric stenosis USG Chronic sinusitis CT scan Chronic pancreatitis ERCP CIN Cytology (pap) C1- C2 Jefferson's fracture Odontoid view Carotid stenosis Doppler / MR angio / CT angio CSF Rhinorrhea CT scan Diverticulosis Barium enema Diverticulitis CT scan Diffuse esophageal Spasm, Achalasia and any motility disorder of esophagus Manometry Down's syndrome ECHO DCIS Mammography Emergency in case of stable patient FAST Esophageal perforation Flexible endoscopy Extra adrenal pheochromocytoma MRI Gastric bleed Tc99 RBC scan >> Angiography Gastroesophageal reflux (GERD) Gold standard-24 hr pH mon¬itoring (Demeester score) Best - endoscopy Heart transplant rejection Biopsy Hirschsprung disease Rectal biopsy FNH of liver Tc99 sulfur colloid scan FAP Sigmoidoscopy Hydrocephalus Infants – USG Adults - MRI Head injures Parenchymal bleeds Subarachnoid hemorrhage Non contrast CT Insulinoma Intra operative endoscopic ultra sound (EUS) Intersititial Lung disease, bronchiectasis HRCT Lymphangiomyomatosis HRCT Le Fort's fracture CT scan Meningiomas Gd-enhanced MRI Minimal ascites USG Neuroendocrine tumours Somatostatin receptor scintigraphy(SRS) Nasopharyngeal Angiofibroma Contrast CT (Antral sign) Obstructive jaundice USG Osteoporosis DEXA scan Osteomyelitis Bone scan (Tc99 MDP) Ovarian reserve FSH Parathyroid glands Sestamibi scan, Tc-thallium scan subtraction Pre operative Insulinoma Intra arterial Ca+2 injection angiography Post menopausal, Uterine bleeding Fractional curettage Pneumo peritoneum X-ray abdomen in left lateral decubitus Pulmonary sequestration CT Angio Pheochromocytoma MIBG scan Pericardial effusion ECHO Pericarditis CT > MRI Pneumo thorax CXR PA view with full expiration Pulmonary embolism PTA (Gold standard) > Doppler > D-Dimer (screening) Recurrence of a tumor PET scan Reticulo endothelial system Tc99 sulfur colloid scan Recurrent GIST PET scan Rhabdo myosarcoma MRI Reversible myocardial Ischemia Thallium scan Superior sulcus tumor CE - MRI Subacute intestinal obstruction X-ray abdomen Schwannomas Gd-enhanced MRI Sella turcica Lateral view of x-ray skull Synovial pathology Gd-enhanced MRI Temporal bone CT scan Traumatic paraplegia MRI Thyroid & breast FNAC Toxoplasmosis IgA - ISAGA > IgM Advanced ren