GI Flashcards
Causes of linitis plastica
Imaging appearances
#1 Scirrhous adenoCa stomach #2 Lymphoma - often thicker >4 cm #3 Mets (usually breast and lung)
Rigid wall of stomach with reduced distension and altered fold pattern; ddx = gastritis from other causes (eosinophilic, TB, corrosive ingestion)
What entity causes Rams horn sign?
- Crohn disease
- Causes tubular/conical appearance of distal stomach and antrum
Imaging appearances in GVHD
When does this occur?
- 100 days post BMT, after induction chemo or radiation
- Most commonly SB and colon
- Mural and fold thickening progressing to ribbon like bowel, separated loops (on upper GI)
- Segmental involvement
Imaging findings celiac disease
Barium
- small intestinal dilatation
- intussusceptions
- jejunoileal fold pattern reversal
- moulage sign (loss of normal folds)
CT (similar findings)
- reversal of folds
- ileal fold thickening
- prominent nodes - can contain fat/cavitate
- splenic atrophy
- *increased risk of adenocarcinoma and lymphoma of SB
Ddx for nodular, thickened small bowel folds
Whipples - sand-like nodules in the jejunum, thickened folds, big low attenuation nodes
MAI (pseudo Whipples) - segmental or diffuse small bowel wall thickening + big nodes
DDx: lymphoma
Most common location of TB in GI tract
Terminal ileum
C-RADS findings and F/U
C0: inadequate study
C1: normal colon/benign lesion: routine screening to be continued
C2: indeterminate polyp: surveillance or colonoscopy
- 6-9 mm in diameter
<3 in number
C3: possibly advanced adenoma: follow up colonoscopy
>10 mm in diameter
>3 in number with each 6-9 mm
C4: colonic mass likely malignant: urgent surgical referral
has associated luminal narrowing
has extra-colonic extension
Which rectal cancer nodes are local versus mets? What are concerning features?
Local - mesorectal, sup/mid/inf rectal, int iliac, sacral, sigmoidal mesentery
Concerning features: size not very reliable; consider morphology - round, irregular or heterogeneous signal
Which stages are locally advanced in rectal ca?
T3c-d, T4, N1 and N2 - require neoadjuvant chemo
Standard surgical tx for rectal Ca
TME
Where do Barrett’s esophagus strictures occur?
More commonly lower esophagus, if you see stricture in mid esophagus then Barrett’s is #1 cause
(ddx: caustic ingestion, radiation changes, drugs, etc)
Associated with pseudodiverticulosis
Ddx for enhancing lesion in the small bowel
- Carcinoid (usually TI)
- AdenoCA (ampulla or jejunum, varied appearance from polypoid to infiltrating mass)
- Mets (most common SB neoplasms, usu multiple)
- GIST (can be polypoid, central hypoattenuation)
- Lymphoma (usu ileum)
Imaging findings scleroderma
Esophagus most commonly involved (dilated)
Small bowel also has findings:
– hidebound bowel (multiple thin folds, stack of coins)
– SB dilation, usu duodenum
– pseudosacculations/pseudodiverticula
– benign pneumatosis or pneumoperitoneum
Causes of pneumatosis
- AMI #1
- Severe infx (yersinia, TB, amebiasis, etc.)
- COPD/ lung disease
- Drugs
- CTD - scleroderma
Causes of toxic megacolon
- UC (most common, look for pseudo-polyps and thumbprinting on x-ray)
- Ischemic colitis
- Pseudomembranous colitis
Other less common causes: Crohns, infection (TB)
