Clinical Scorecard: Assessment of Liver Function Through Multiphase Hepatic CT: Evaluating the Diagnostic Efficacy of Iodine Uptake and Volumetric Metrics

At a Glance

Key Highlights

• ICG-R15 is a validated dynamic quantitative test for liver function and hepatectomy safety, with ≥20% indicating severe dysfunction and contraindication for major hepatectomy.
• 99mTc-GSA scintigraphy provides imaging-based regional hepatocyte function assessment but is limited by availability, cost, complexity, and radiation exposure.
• Multiphase hepatic CT iodine uptake parameters (ECV and IWR) and volumetric indices correlate with liver fibrosis and function, potentially enabling liver function assessment during routine tumor imaging.

Guideline-Based Recommendations

Diagnosis

• Use ICG-R15 as a reference standard for dynamic liver function assessment prior to hepatectomy.
• Consider 99mTc-GSA scintigraphy for patients with limited future liver remnant or underlying liver disease when volume modulation strategies are planned.
• Employ multiphase hepatic CT iodine uptake parameters and volumetry as adjuncts to evaluate liver function and fibrosis.

Management

• Avoid major hepatectomy in patients with ICG-R15 ≥ 20% due to severe liver dysfunction risk.
• Use liver function assessment to guide surgical planning and minimize postoperative liver failure.
• Incorporate imaging-based liver function tests to complement biochemical and clinical scoring systems.

Monitoring & Follow-up

• Monitor liver function progression using dynamic tests like ICG-R15 and imaging modalities.
• Assess postoperative liver failure using standardized definitions (e.g., ISGLS criteria).

Risks

• Recognize that static biochemical markers and clinical scores may have limited predictive value for hepatic decompensation.
• Consider radiation exposure and technical complexity when using 99mTc-GSA scintigraphy.
• Be aware of limitations of CT volumetry alone in predicting liver dysfunction without parenchymal damage information.

Patient & Prescribing Data

Patients with hepatobiliary tumors undergoing liver function evaluation for surgical planning

Dynamic liver function tests (ICG-R15) and imaging-based assessments guide safe extent of hepatectomy and predict postoperative outcomes.

Clinical Best Practices

• Integrate ICG-R15 testing as a next-step dynamic liver function assessment following static biochemical tests.
• Use multiphase hepatic CT iodine uptake parameters alongside volumetric indices to enhance liver function evaluation during routine imaging.
• Apply 99mTc-GSA scintigraphy selectively in patients with compromised liver function or planned volume modulation.
• Exclude patients with confounding factors (portal venous occlusion, prior hepatectomy, biliary obstruction) when interpreting imaging-based liver function tests.
• Define clinically significant post-hepatectomy liver failure using ISGLS criteria (grade B or C) for outcome assessment.

References

• European guidelines on liver function assessment before hepatectomy
• International Study Group for Liver Surgery (ISGLS) definition of post-hepatectomy liver failure
• ICG retention test methodology and clinical utility