Gastrointestinal Flashcards
Drug causes of hyperattenuating liver?
Amiodarone, Thorotrast, gold
Differential for multiple tiny hypoattenuating liver lesions?
Candidiasis (immunocompromised)
Mets
Lymphoma
Biliary hamartomas
Caroli’s
Hypervascular metastases?
NMTRS
Neuroendocrine
Renal cell
Thyroid
Melanoma
Sarcoma
Choriocarcinoma
HCC
5 key points
Occurs in cirrhotics
AFP often elevated
Arterial phase enhancement
Portal venous phase wash out
Locally invasive - portal vein, hepatic veins, biliary tree
On FNH:
1. Composition?
2. Classic MR appearance?
3. Enhancement pattern?
4. Central scar characteristics?
- Normal hepatocytes, abnormal biliary drainage, large central feeding artery with branching vessels “spoke-wheel”
- May be iso to low on T1 and iso to high T2, if the central scar is present it is T2 bright. “stealth lesion”
- Arterial enhancement with no washout, there is retention of hepatocyte specific contrast at 20 mins
- Following administration of extra-cellular contrast agent, central scar is low on arterial + portal venous and hyperenhancing/retains contrast on delayed phase. Following admin of hepatobiliary contrast, central scar is hypoenhancing on all phases.
On hepatic adenoma:
1. Composition?
2. MR characteristics?
3. Contrast enhancement?
4. Late phase imaging?
- Hepatocytes with diminished function that contain abundant fat and glycogen, traditionally don’t have bile ducts or Kupffer cells although this is variable
- Non-haemorrhagic adenomas are variable on T1 and slightly hyperintense on T2 - drop in signal on OOP
- Arterial enhancement then become isointense on portal venous
- Reduced uptake of Primovist on HB phase - hypointense compared with surrounding liver
Most common cancers to metastasise to spleen?
Melanoma (most common)
Breast
Ovary
Lung
Colon and other GI
Abdominal complications following stem-cell transplant?
Early
Pseudomembranous colitis
Infective - CMV, fungal
Veno-occlusive disease (first 30 days)
Acute GVHD (2-3 months) - small bowel wall thickening, abnormal mucosal enhancement, dilatation, fluid-filled, bowel loop separation
Late
Chronic GVHD
Haemorrhagic cystitis
Post-transplant lymphoproliferative disorder
Autoimmune pancreatitis true or false
- CA 19-9 may be raised
- duct-penetrating sign is a sign of malignancy
- usually associated with duct dilatation
- spectrum of IgG4 disease
T
F
F
T
What lesion is this?
Early arterial enhancement on CEUS in a spoke-wheel centrifugal pattern, followed by portal venous washout
FNH
On rectal cancer:
- what are the regional nodes?
- what are considered metastatic?
- what is the exception?
- what is used to predict involvement of the CRM?
Mesorectal, presacral, inferior mesenteric, internal iliac, obturator
- external iliac, common iliac and inguinal are considered metastatic
- EXCEPT if a low rectal tumour extends below the dentate line, then inguinal can be considered regional
- if the tumour extends to within 1mm of the mesorectal fascia
On oesophageal cancer:
- key question radiology can answer regarding staging?
- what kind of cancer does Barrett’s predispose you to and what is the pattern?
- where does it metastasise to?
T3 - invades adventitia or T4 - invades adjacent structures
Adenocarcinoma, reticular mucosal pattern
Liver - lung - bone - kidney - brain
Carney’s triad?
Carneys eat garbage
Chondroma
Extra adrenal phaeo
GIST
On GIST:
- benign or malignant?
- association?
- if malignant, where do they met to?
Usually benign, with no lymph node involvement
NF1, Carney’s triad
Liver
Most common extra-nodal site for NHL?
The stomach
Differential for linitis plastica?
Scirrhous gastric adenocarcinoma
Breast met (most common)
Lung met
Lymphoma
Inflammatory causes
On gastric volvulus:
- GOJ position?
- the GOJ is below the antrum in mesentero-axial volvulus
- the GOJ is above the antrum in organo-axial volvulus
On Meckel’s diverticulum:
- what is it?
- what is the rule of 2s?
- diverticulum of the ileum
- 2% of population, 2 feet (60cm) of IC valve, 2 inches (5cm) long, 2 type of heterotopic mucosa, presents at the age of 2
GI manifestations of Behcet’s?
Ileocecal ulcer - mimics Crohn’s
Budd-Chiari
Oesophageal ulcer
Differential for small bowel tumour?
Which ones have LNs?
GIST location and characteristic?
Lymphoma location and characteristic?
Adenocarcinoma location and characteristic?
Carcinoid location and characteristic?
Carcinoid
Adenocarcinoma
Lymphoma
GIST
All but GIST
Stomach > small bowel > other locations
Extraluminal/exophytic
Ileum. Diffuse wall thickening with aneurysmal dilatation. May be multiple sites
Duodenum > jejunum > ileum
Circumferential thickening, shouldered margins, invasion of surrounding fat/mesentery
Appendix and distal ileum
Hypervascular, intense desmoplastic reaction, calcification, may be multiple
Immune suppressed patient with small bowel thickening?
Typhilitis / neutropenic enterocolitis
What cancers do patients with Celiac get?
Adenocarcinoma
Lymphoma
T cell lymphoma
Most common pancreatic duct variant and clinical significance?
Pancreas divisum - main pancreatic duct/dorsal duct drains via the minor papilla
Pancreatitis
Types of choledochal cyst?
Most common type?
Type 1 - extrahepatic duct dilatation
Type 2 - true diverticulum from extrahepatic duct
Type 3 - dilatation of extrahepatic duct within the duodenal wall
Type 4 - intra and extrahepatic duct cysts/dilatation
Type 5 - multiple intrahepatic duct cysts/dilatation - Caroli’s
Type 1 - associated with anomalous pancreaticobiliary duct junction
