GI/GU

Question 1

Adrenal adenoma

Answer 1

Rapid washout
DDX- Phaeochromocytomas, hyprvascular mets (HCC, RCC)
>60% ABSOLUTE WASHOUT
>40% RELATIVE WASHOUT

HCC and RCC mets can contain fat

on portal venous imaging if >120HU more likely to be phaeo or hypervascular mets

Question 2

Adrenal cortical carcinoma

Answer 2

Syndromes- MEN 1, Li Fraumeni, Carney complex, FAP

Large >6cm, necrosis, calc, hemorrhage

Question 3

Phaechromocytoma

Answer 3

MEN 2, VHL, NF1

Heterogenous, large (4-6cm)
necrosis/ cystic change
avidly enhance- more in PV than arterial (>120HU on PV)

Ocrtreotide/ MIBG

Cannot confidentally differentiate from ACC > urinary metenephrines

Question 4

MEN 1

Answer 4

• Hyperparathyroidism
• Pancreatic neuroendocrine tumours (gastinoma)
• Pituitary adenomas (prolactinoma commonest)

Question 5

FNH

Answer 5

T1 = iso / hypointense

T2 = iso /hyperintense, hyperintense central scar

T1 C+ (Gd)
central scar retains contrast on delayed scans
slightly hyperintense / isointense to liver on portal venous phase
early intense arterial phase enhancement

T1 C+ (Eovist/Primovist)
early arterial enhancement, persists into delayed phases, fades toward background liver intensity on the delayed HPB phase, with a small amount of enhancement remaining (cf. adenomas, which are classically hypointense relative to liver on hepatobiliary phase)
central fibrotic scar typically does not enhance on hepatobiliary phase

CT:
bright HOMOGENOUS arterially enhancing lesion, scar doesnt enhance
PV- slightly hyperattenuating / isoattenuating to liver, central scar can enhanced on very delayed imaging

Takes up sulfur colloid (Kuppfer cells) + HIDA

Question 6

Hepatic adenoma

Answer 6

• contains fat/ calc/hemorrhage
  CT
• transient homogeneous enhancement, isodensity on PV and delayed phase images

MRI
T1: HYPO/ISO/HYPER

T2: mildly hyperintense

T1 C+ (Gd)

early arterial enhancement and become nearly isointense about liver on delayed

T1 C+ (Eovist/Primovist):
usually appears HYPOINTENSE on HPB (20 mins after injection) due to reduced uptake of Eovist (cf FNH)

UPTAKE ON HIDA SCAN

Question 7

Massive splenomegaly

Answer 7

1. CML
2. Myelofibrosis.
3. Malaria.
4. Gaucher’s disease.
5. Lymphoma*.

Question 8

Colitis patterns

Answer 8

• RIGHT- Yersinia, Salmonella, and colonic TB , typhilitis
• PANCOLITIS- E. coli, CMV, and C. difficile, pseudomembranous colitis

LEFT- Shigella, ishcaemic colitis, radiation, epiploic appendagitis

remember immunotherapy related colitis