GI radiology Flashcards
- Recognize free intra-abdominal free air on abdominal radiographs and computed tomography (CT) and describe how patient positioning affects sensitivity for its detection.
Upright chest is best for finding free intra-abd free air. The air will collect under the diaphragm
benefit of fluoroscopy
it is seen in real time with x ray images, mobile tabel and video monitor.
fluoroscopy negatives
significant radiation dose
contrast agents
air, barium (avoid upstream of mechanical colon obstruction), iodinated water soluble (use in gut perforations, avoid high osmolarity)
what do we look for in barium swallow
aspiration into pharynx
biphasic esophagram
using air and contrast- for dysphagia and heartburn to detect reflux, hiatal hernia, aspiration, neoplasm, esophagitis
when fundus has air and body of stomach has contrast, are they supine or prone
prone- fundus is posterior
small bowel follow through indications
indications: IBD, malabsorption, diarrhea, partial SBO, unexplained GI bleed
What does small bowel follow through evaluate
distal duodenum, duodenojejunal junction to ileocecal valve
small bowel pathology diseases identified
crohns, lymphoma tuberculosis, sprue, adhesions, obstruction
enteroclysis
provides more detail than SBFT- tube goes through jejunum and ileum. Methylcellulose instilled into jejunum after barium and can be used with CT
Enteroclysis uses
same as SBFT
barium enema indications
double contrast: rectal bleeding, polyps, cancer, IBD. Single contrast: fistula or sinus tract, if unable to tolerate double.
Contraindications for barium enema
acute perforation, colitis (toxic megacolon), immediately after biopsy
barium enema contrast benefits/disadvantages
water soluble, risk for intestinal perforation, therapeutic for disimpaction
Ultrasound advantages
no radiation, safe in pediatric and pregnant pts, real time, portable.
ultrasouund disadvantages
body habitus, operator dependent, intestinal gas can affect quality
ultrasound indications
gallbladder, solid organ lesions (solid vs cystic), appendicitis, vascular flow (doppler), image guidance procedures
CT types
without IV contrast: renal stone or hemorrhage. With IV contrast: ischemic, infectious, tumor, arterial. Enteric contrast: oral or rectal. CT cholangiopancreatography
IV contrast risks
nephrotoxicity, allergic rxn
CT and pregnancy
contraindicated unless life threatening
nuclear medicine benefits
functional information
nuclear medicine uses
bile leak, cholecystitis, gastric motility, source of GI bleed
