Radiologic Anatomy - Abdomen/Pelvis Flashcards
Broad Topic-Indications for Abdominal Imaging
Abdominal Complaints
Gastrointestinal: Liver, Biliary Tract, Pancreas, Trauma
Genitourinary (women’s health included here)
GI Imaging modalities
Metal salts (barium sulfate0
Capsule endoscopy
Luminal Contrast-Mucosal changes
CT Scan- All things abdomen, neoplasm, etc
MRI-Like CT, small mucosal/focal lesions not well detected
Ultrasound-Mainly for solid organs and biliary tract ie Gallbladder
Endoscopy-Visualize mucosa from esophagus to colon
CT indications for Abdomen
All things abdomen, neoplasm, etc
MRI indications for Abdomen
small mucosal/focal lesions not well detected
Ultrasound indications for abdomen
Mainly for solid organs and biliary tract ie Gallbladder
Endoscopy use for abdomen
Visualize mucosa from esophagus to colon
Luminal contrast indications for abdomen
Looks at mucosal changes
What we look for with Upper GI Endoscopy
dysphagia, chest pain, bleeding (ulcers), dyspepsia (pharynx to duodenum)
Small bowel endoscopic or barium edema can look for:
bleeding not localized to upper or colon,
diarrhea, inflammatory bowel disease(IBD), obstruction, malignancy, fistula (duodenum to ileum)
Colonoscopy can look for
Rectal bleeding, IBD, malignancy, obstruction, length of colon
What is Positron Emission Tomography
(PET Scan)
Uses radioactive tracer to pinpoint areas of high metabolic activity
- Interacts with protein target
- FDG for glucose metabolism in tumors
Combined with CT for anatomic clarity
Modality to use for Esophageal Cancer, GERD, Stricture,Peptic Ulcers
Endoscopy most commonly used.
Modality to use for Crohn’s Disease, Meckel’s diverticulum, cancer, SBO
Capsule endoscopy, CT, MRI (SBO, Crohn’s disease)
What modality to use for Diverticulosis, colitis, polyps, cancer, volvulus
Colonoscopy, MRI, CT (diverticulitis). Barium enema with larger polyps, severe diverticulosis.
What modality to use for Diffuse Hepatic: Cirrhosis
CT first choice. Good survey scan, moderately sensitive
What modality to use for Focal Hepatic: Liver mass
Ultrasound often used initially then CT if needed. MRI can f/u on findings with survey scans obtained by U/S and CT
What modality to use for abdominal trauma
CT is gold standard. Bedside ultrasound (eFAST). MRI not used at this point in trauma-Why??
Modality to use for Pancreatic Inflammation/Tumor
Initial study CT. U/S limited use
Pros/Cons of plain films for assessing Kidney, ureters and bladder
“Gas, mass, bones, stones”
Renal outline can be seen, ureters not so much
Urinary tract calcifications-less sensitive than previously thought (40-60% vs. 80% sensitivity)
Rarely, masses are detected
Bony lesions can be seen eg. prostate cancer metastasis
Multi-detector (spiral) CT has had greatest impact and Essentially eliminated the intravenous pyelogram (IVP) in what area
GU
Advantages of GU CT (spiral)
Exams are quick and thin slices allow for detailed exams
CT without contrast for renal/ureteral stones-Why without contrast??
CT with IV contrast for hematuria, mass vs cyst detection, renal anatomy (too small or too large), staging renal CA, trauma, vascular structures
Advantages of Ultrasound for GU imaging
widely available, no contrast, no radiation
Hypoechoic vs. Hyperechoic in Ultrasound
Hypoechoic-darker than surrounding tissue
Hyperechoic-lighter than surrounding tissue
Why can an MRI be advantageous for GU in someone with normal renal function?
overall safer to give Gadolinium vs. iodine contrast (CT)
