Tc-GSA SPECT/CT fusion imaging for hepatectomy candidates with extremely deteriorated ICG value.

Purpose: The value of indocyanine green (ICG) test is negatively affected in patients with intrahepatic shunt, ICG excretory defect, or jaundice. This study evaluated Tc-GSA SPECT/CT fusion imaging for assessing liver function in patients with severely deteriorated ICG values.

Materials And Methods: Thirteen hepatectomy candidates with ICG retention rates over 40% were retrospectively analyzed. The ICG clearance rate (KICG) and estimated KICG obtained by Tc-GSA scintigraphy (KGSA) were used to evaluate preoperative whole liver function. Remnant liver function was assessed using the remnant (rem) KICG (= KICG × volumetric rate) and remKGSA (= KGSA × functional rate) indices; hepatectomy was considered unsafe for values < 0.05. The correlations of remKICG and remKGSA with postoperative mortality and morbidity were also investigated.

Results: KGSA values were significantly greater than KICG values (median: 0.12 vs. 0.059; p < 0.01); remKGSA values were greater than remKICG values in all patients (median: 0.107 vs. 0.0413; p < 0.01). Hepatectomy was considered unsafe in 70% patients using remKICG, and in none of those using remKGSA; liver failure or postoperative mortality did not occur.

Conclusions: Tc-GSA SPECT/CT fusion imaging enables more accurate liver function assessment than the ICG test in patients with severely deteriorated ICG values.