Viva · Specialty
Gastrointestinal and Hepatobiliary Viva Questions
Oral-exam style questions and answers on gastrointestinal and hepatobiliary for MD, DNB and super-specialty practical examinations. Each answer links back to the playbook or Library entry it was written from.
- Define the Nyquist limit and list four ways to correct aliasing on pulsed-wave Doppler.
- The Nyquist limit is half the pulse repetition frequency and represents the maximum Doppler shift that can be measured without aliasing. Corrections include raising the PRF, shifting the baseline, lowering the transmit frequency, using a shallower sample gate, or switching to continuous-wave Doppler.
- Compare colour Doppler and power Doppler.
- Colour Doppler encodes mean velocity and variance, is angle-dependent and can alias. Power Doppler encodes signal amplitude, is angle-independent, does not alias and is more sensitive to slow flow, but provides no velocity or direction information and is prone to flash artefact.
- What makes a liver shear-wave elastography acquisition reliable?
- At least ten valid measurements taken from a right-lobe region at least one centimetre below the capsule, avoiding vessels and artefacts, with a small interquartile range relative to the median, commonly thirty percent or less. The device and failure rate should be reported.
- How do Baveno VII liver stiffness thresholds guide assessment of compensated advanced chronic liver disease?
- Liver stiffness below 10 kilopascals argues against compensated advanced chronic liver disease, 10 to 15 kilopascals is indeterminate, and above 15 kilopascals supports clinically significant portal hypertension and triggers decisions such as variceal screening, always interpreted with the clinical context and device used.
- Give four causes of falsely high liver stiffness.
- Common causes are hepatic congestion, acute inflammation or hepatitis, cholestasis, recent food intake, and technical factors such as a narrow intercostal window or measurements taken too close to the capsule.
- Differentiate strain elastography from shear-wave elastography.
- Strain elastography measures relative tissue deformation under compression and is qualitative or semi-quantitative, while shear-wave elastography measures the speed of an induced shear wave and provides absolute stiffness in metres per second or kilopascals, allowing serial comparison on the same platform.
- What are the components of the original Balthazar CT Severity Index?
- It is the sum of the Balthazar pancreatic and peripancreatic inflammatory grade, scored from 0 to 4, and the extent of pancreatic necrosis, scored from 0 to 6.
- How are Balthazar grades A to E scored?
- Grades A, B, C, D and E receive 0, 1, 2, 3 and 4 points respectively, progressing from a normal pancreas to multiple collections or gas in or adjacent to the pancreas.
- How is pancreatic necrosis scored in the original CTSI?
- No necrosis scores 0, up to 30% scores 2, more than 30% to 50% scores 4, and more than 50% scores 6.
- How does the Modified CTSI differ from the original CTSI?
- It simplifies pancreatic inflammation to 0, 2 or 4 points, simplifies necrosis to 0, 2 or 4 points, and adds 2 points for one or more extrapancreatic complications.
- Which extrapancreatic complications are included in the Modified CTSI?
- They include pleural effusion, ascites, vascular complications, extrapancreatic parenchymal complications and gastrointestinal tract involvement.
- How are the original CTSI and Modified CTSI severity categories defined?
- Original CTSI scores of 0–3, 4–6 and 7–10 indicate mild, moderate and severe disease. Modified CTSI scores of 0–2, 4–6 and 8–10 indicate mild, moderate and severe disease.
- Is CT severity according to the Modified CTSI equivalent to Revised Atlanta clinical severity?
- No. Modified CTSI is a morphological imaging score, whereas Revised Atlanta severity is based primarily on organ failure and whether it is transient or persists for more than 48 hours.
- What is a common scoring error with extrapancreatic complications in the Modified CTSI?
- Their presence adds only 2 points in total, irrespective of how many qualifying extrapancreatic complications are present.
- What is the BCLC staging system?
- The Barcelona Clinic Liver Cancer system stages hepatocellular carcinoma by integrating tumour burden, liver function and cancer-related ECOG performance status, and links each stage to a treatment strategy.
- Enumerate the five BCLC stages.
- Stage 0 is very early, A is early, B is intermediate, C is advanced and D is terminal stage.
- What defines BCLC stage 0?
- A single HCC measuring 2 cm or less, with preserved liver function, ECOG performance status 0 and no vascular invasion or extrahepatic spread.
- What defines BCLC stage A?
- A solitary HCC larger than 2 cm irrespective of size, or two to three nodules each measuring 3 cm or less, with preserved liver function and ECOG performance status 0.
- How does the 2026 BCLC update define multifocal stage B disease?
- Stage B includes more than three nodules, or two to three nodules with at least one larger than 3 cm, provided there is no vascular invasion or extrahepatic spread and liver function and performance status are preserved.
- Which BCLC stage is conventionally associated with TACE?
- BCLC-B. TACE is most appropriate for well-defined arterialised tumours when portal flow is preserved and selective catheterisation is feasible; not every stage B patient is a TACE candidate.
- What defines BCLC stage C?
- Portal invasion, extrahepatic spread or cancer-related ECOG performance status 1–2 in a patient whose liver function permits active treatment. Systemic therapy is the usual treatment direction.
- What is the common staging error with a large solitary HCC?
- A large solitary HCC should not automatically be called BCLC-B. If liver function is preserved, performance status is 0 and there is no vascular invasion or extrahepatic spread, it remains BCLC-A.
- What is the Bismuth–Corlette classification?
- It is an anatomical classification of perihilar cholangiocarcinoma based on the longitudinal extent of tumour involvement in relation to the hepatic duct confluence and the right and left hepatic ducts.
- Enumerate the Bismuth–Corlette types.
- Type I is below the confluence, type II involves the confluence, type III extends unilaterally into either hepatic duct, and type IV shows bilateral or multifocal biliary involvement.
- How do types I and II differ?
- Type I remains below the right–left hepatic duct confluence, whereas type II reaches and involves the confluence without extending into either main hepatic duct.
- How do types IIIa and IIIb differ?
- Type IIIa extends into the right hepatic duct, whereas type IIIb extends into the left hepatic duct.
- What constitutes a Bismuth–Corlette type IV tumour?
- Type IV denotes extension into both right and left hepatic ducts or multifocal biliary involvement.
- What is the clinical importance of the Bismuth–Corlette classification?
- It communicates the longitudinal biliary extent of perihilar cholangiocarcinoma and assists planning of resection and biliary drainage. It must be combined with assessment of vascular, hepatic, nodal and metastatic disease.
- What are the major limitations of the Bismuth–Corlette classification?
- It does not adequately describe vascular invasion, lobar atrophy, future liver remnant, lymph-node involvement or distant metastases. Therefore, it cannot independently determine stage, prognosis or resectability.
- What is the 'small bowel faeces sign' and what does it indicate?
- The small bowel faeces sign refers to particulate faecal-like material with gas bubbles within dilated small bowel loops, indicating stasis and helping to localise the transition zone in subacute obstruction.
- How do you differentiate an SMA embolus from an SMA thrombosis on CT angiography?
- An embolus typically lodges distal to the origin of the middle colic artery, whereas thrombosis usually occurs at the vessel ostium in the setting of severe atherosclerotic disease.
- What are the late, irreversible CT signs of bowel ischaemia?
- Late signs include pneumatosis intestinalis, portal venous gas, lack of bowel wall enhancement, and bowel wall thinning, all indicating transmural infarction.
- Why is a competent ileocaecal valve dangerous in large bowel obstruction?
- A competent valve creates a closed-loop obstruction, preventing retrograde decompression and placing the caecum at high risk for perforation due to its large resting diameter (Law of Laplace).
- What is the Child–Pugh classification used for?
- It grades hepatic functional impairment in chronic liver disease, particularly cirrhosis, and supports prognostic, procedural and treatment-risk assessment.
- Which five parameters constitute the Child–Pugh score?
- Total bilirubin, serum albumin, INR or prothrombin-time prolongation, ascites and hepatic encephalopathy.
- How is each Child–Pugh parameter scored?
- Each parameter receives 1, 2 or 3 points, with increasing points representing greater impairment. The five scores are added to produce a total between 5 and 15.
- What total scores define Child–Pugh classes A, B and C?
- Class A is 5–6 points, Class B is 7–9 points and Class C is 10–15 points.
- Which Child–Pugh variables are subjective?
- Ascites and hepatic encephalopathy are partly subjective and may change after diuretic, lactulose or other treatment.
- Should both INR and prothrombin-time prolongation be scored?
- No. They are alternative measures of the same coagulation component, so only one should contribute to the score.
- What does Child–Pugh Class C indicate?
- It indicates the most severe category of hepatic functional impairment, corresponding to a total score of 10–15.
- What is the purpose of the Hinchey classification?
- It grades the anatomical severity of acute diverticulitis, progressing from a localised abscess to generalised purulent or faecal peritonitis.
- Enumerate the original Hinchey stages.
- Stage I is a pericolic abscess, stage II is a pelvic or other distant abscess, stage III is generalised purulent peritonitis and stage IV is generalised faecal peritonitis.
- What is the difference between modified Hinchey Ia and Ib?
- Stage Ia is confined pericolic inflammation or phlegmon without an abscess, whereas stage Ib is a confined pericolic or mesocolic abscess.
- What constitutes modified Hinchey stage II?
- Stage II is a pelvic, distant intra-abdominal or retroperitoneal abscess rather than a collection confined to the pericolic or mesocolic region.
- How do Hinchey stages III and IV differ?
- Stage III is generalised purulent peritonitis without gross faecal contamination, while stage IV is generalised faecal peritonitis from free colonic perforation.
- Can CT reliably distinguish Hinchey III from Hinchey IV?
- Not always. CT can demonstrate free perforation, free gas and diffuse fluid, but the distinction between purulent and faecal peritonitis is fundamentally clinical or operative.
- Does pericolic extraluminal gas automatically indicate Hinchey III diverticulitis?
- No. Localised pericolic gas can occur with a contained perforation; Hinchey III specifically requires generalised purulent peritonitis.
- Why should a radiology report specify which Hinchey version is being used?
- The original classification contains stages I–IV, whereas modified systems add stage 0 and subdivide stage I. Naming the version prevents ambiguity in multidisciplinary communication.
- What is the purpose of LI-RADS Treatment Response Assessment?
- It standardises lesion-level assessment of presumed or proven hepatocellular carcinoma after locoregional treatment using post-treatment multiphase CT or MRI.
- What are the LR-TR categories in the nonradiation algorithm?
- They are LR-TR Nonevaluable, Nonviable, Equivocal and Viable.
- What are the LR-TR categories in the radiation algorithm?
- They are LR-TR Nonevaluable, Nonviable, Nonprogressing and Viable. Equivocal is not a radiation-algorithm category.
- What is the major imaging feature of viability in LI-RADS TRA v2024?
- The major feature is masslike enhancement of any degree in any contrast-enhanced phase.
- How is stable masslike enhancement classified after TACE and after TARE?
- After TACE, definite masslike enhancement is LR-TR Viable. After TARE, masslike enhancement that is stable or decreased in size over time is LR-TR Nonprogressing.
- Which MRI ancillary features favour viability?
- Diffusion restriction and mild-to-moderate T2 hyperintensity favour viability. They may support an optional upgrade to LR-TR Viable when present in the required area and, after radiation therapy, show the required temporal increase.
- When should LR-TR Nonevaluable be assigned?
- Assign LR-TR Nonevaluable when masslike enhancement cannot be assessed because the required imaging is technically inadequate, degraded or incomplete.
- What is the principal interpretation pitfall after radiation-based therapy?
- Persistent enhancement should not automatically be labelled viable. After TARE or SBRT, stable or decreasing masslike enhancement is LR-TR Nonprogressing, whereas new or increasing masslike enhancement is LR-TR Viable.
- What is the MELD score?
- The Model for End-Stage Liver Disease is an objective prognostic score that estimates 90-day mortality in advanced liver disease and helps determine medical urgency for liver transplantation.
- Which variables are included in the original MELD score?
- The original MELD score uses serum bilirubin, INR and serum creatinine, with natural logarithmic transformation.
- How does MELD 3.0 differ from MELD-Na?
- MELD 3.0 retains bilirubin, INR, creatinine and sodium, adds albumin and an adult female-sex term, introduces interaction terms and lowers the creatinine ceiling from 4.0 to 3.0 mg/dL.
- What laboratory bounds are used for MELD 3.0?
- Bilirubin, INR and creatinine have a minimum of 1.0; creatinine is capped at 3.0 mg/dL, sodium at 125–137 mmol/L and albumin at 1.5–3.5 g/dL.
- How is creatinine handled in a patient receiving dialysis?
- For MELD 3.0, creatinine is set to 3.0 mg/dL after at least two dialysis treatments in the preceding 7 days or 24 hours of continuous veno-venous haemodialysis during that period.
- How is the MELD score interpreted?
- The score ranges from 6 to 40. A higher score represents greater predicted 90-day wait-list mortality and therefore greater urgency for transplantation.
- Which score is used for a child younger than 12 years?
- PELD, the Paediatric End-Stage Liver Disease score, is used for candidates younger than 12 years; MELD is used from 12 years onwards in the OPTN system.
- What is the relevance of MELD before TIPS?
- MELD was originally developed in patients undergoing TIPS, and a higher score indicates increased post-procedural mortality risk. It supports risk stratification but must not replace assessment of bilirubin, cardiac reserve, encephalopathy, haemodynamics and the clinical indication.
- What does mRECIST measure that RECIST 1.1 does not?
- mRECIST measures the diameter of the arterially enhancing, viable component of a target lesion, whereas RECIST 1.1 measures the whole lesion diameter regardless of necrosis.
- Define complete response by mRECIST.
- Disappearance of any intratumoural arterial enhancement in all target lesions.
- What are the thresholds for partial response and progressive disease?
- Partial response is at least a 30% decrease in the sum of viable enhancing target-lesion diameters from baseline; progressive disease is at least a 20% increase from the smallest sum recorded since treatment started.
- Which lesion is unsuitable as an mRECIST target lesion?
- A lesion that is not arterially enhancing at baseline, is poorly demarcated, or cannot be measured reproducibly on contrast-enhanced CT or MRI.
- How are portal vein tumour thrombus and new ascites handled?
- Both are non-target findings assessed qualitatively rather than measured; a new effusion or ascites should be confirmed as malignant before being called progression.
- Why can mRECIST and RECIST 1.1 disagree after TACE?
- A lesion may be largely necrotic yet unchanged or larger in overall size, giving stable disease by RECIST 1.1 but a partial or complete response by mRECIST.
- What is the basis of the Todani classification?
- It classifies congenital bile duct cysts according to the site, extent and morphology of intrahepatic and extrahepatic biliary dilatation.
- What are the principal Todani types?
- Type I is extrahepatic duct dilatation, type II is an extrahepatic diverticulum, type III is a choledochocele, type IV comprises multiple biliary dilatations and type V is isolated intrahepatic duct ectasia.
- How are type I choledochal cysts subdivided?
- Type IA is marked cystic dilatation of the entire extrahepatic duct, type IB is a focal segmental dilatation and type IC is diffuse fusiform or cylindrical extrahepatic duct dilatation.
- What is a type III choledochal cyst?
- Type III is cystic dilatation of the intramural distal common bile duct protruding into the duodenum, termed a choledochocele.
- How do type IVA and type IVB differ?
- Type IVA involves multiple dilatations of both the intrahepatic and extrahepatic ducts, whereas type IVB has multiple dilatations confined to the extrahepatic ducts.
- What is Todani type V disease?
- Type V is segmental or diffuse saccular dilatation confined to the intrahepatic bile ducts and corresponds to Caroli disease.
- What is the difference between Caroli disease and Caroli syndrome?
- Caroli disease denotes isolated intrahepatic bile duct ectasia, whereas Caroli syndrome combines this duct abnormality with congenital hepatic fibrosis.
- What is an important imaging pitfall when diagnosing type IVA disease?
- Secondary intrahepatic duct dilatation caused by distal obstruction should not be mistaken for type IVA. True type IVA shows intrinsic cystic or disproportionate involvement of both the intrahepatic and extrahepatic ducts.
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma
Bismuth–Corlette Classification of Perihilar Cholangiocarcinoma