Clinician overconfidence in visual estimation of the posthepatectomy liver remnant volume: A proximal source of liver failure after major hepatic resection?

Background: Post-hepatectomy liver failure is a source of morbidity and mortality after major hepatectomy and is related to the volume of the future liver remnant. The accuracy of a clinician's ability to visually estimate the future liver remnant without formal computed tomography liver volumetry is unknown. Methods: Twenty physicians in diagnostic radiology, interventional radiology, and hepatopancreatobiliary surgery reviewed 20 computed tomography scans of patients without underlying liver pathology who were not scheduled for liver resection. We evaluated clinician accuracy to estimate the future liver remnant for 3 hypothetical major hepatic resections: left hepatectomy, right hepatectomy, and right trisectionectomy. The percent-difference between the mean and actual computed tomography liver volumetry (mean percent difference) was tested along with specialty differences using mixed-effects regression analysis. Results: The actual future liver remnant (computed tomography liver volumetry) remaining after a hypothetical left hepatectomy ranged from 59% to 75% (physician estimated range: 50%–85%), 23% to 40% right hepatectomy (15%–50%), and 13% to 29% right trisectionectomy (8%–39%). For right hepatectomy, the mean future liver remnant was overestimated by 95% of clinicians with a mean percent difference of 22% (6%–45%; P < .001). For right trisectionectomy, 90% overestimated the future liver remnant by a mean percent difference of 25% (6%–50%; P < .001). Hepatopancreatobiliary surgeons overestimated the future liver remnant for proposed right hepatectomy and right trisectionectomy by a mean percent difference of 25% and 34%, respectively. Based on years of experience, providers with <10 years of experience had a greater mean percent difference than providers with 10+ years of experience for hypothetical major hepatic resections, but was only significantly higher for left hepatectomy (9% vs 6%, P = .002). Conclusion: A clinician's ability to visually estimate the future liver remnant volume is inaccurate when compared to computed tomography liver volumetry. Clinicians tend to overestimate the future liver remnant volume, especially in patients with a small future liver remnant where the risk of posthepatectomy liver failure is greatest.