Developmental anomalies of the right hepatic lobe: systematic comparative analysis of radiological features

Abstract Aim To investigate the radiological characteristics of developmental anomalies of the right hepatic lobe and to systematically compare the efficiency of CT, MR and ultrasound (US) imaging in revealing characteristics of these disorders. Methods This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. CT, MR or US imaging and clinical data of 43 cases with developmental anomalies of the right hepatic lobe were independently reviewed by two experienced radiologists. Systematic comparative analysis of the CT, MR, and US imaging data indicating the main signs of right lobe aplasia or hypoplasia were obtained. Then, c2 tests were performed to compare the results, considering P<0.05 as the significance threshold. Results Agenesis of the right hepatic lobe was observed in two cases. The main imaging features were agenesis of the right lobe and the absence of the right branch of the portal vein and hepatic artery, although one patient exhibited right diaphragm agenesis and a diaphragmatic hernia. Aplasia or hypoplasia of the right hepatic lobe was observed in 41 patients, and among these patients, the main radiological characteristics were as follows: right lobe volume reduction and stenosis of the right portal vein (41 cases, 100%), ectopic gallbladder (39 cases, 95%), left lobe hypertrophy (39 cases, 95%), left portal vein thickening (37 cases, 90%), dextral displacement of the first hepatic portal (32 cases, 78%), caudate lobe hypertrophy (16 cases, 39%), cholelithiasis (12 cases, 29%), portal hypertension (14 cases, 34%), tumor complications (11 cases, 27%), liver abscess (2 cases, 5%), concurrent intrahepatic bile pneumatosis (5 cases, 12%), dysplasia of the right hepatic bile duct (2 cases, 5%), and Budd-Chiari syndrome (2 cases, 5%). Comparative analysis of the main signs of right lobe hypoplasia revealed no significant difference in overall diagnostic efficiency between CT, MRI and US (CT VS MR, X2 = 6.28, P = 0.985; CT VS US, X2 = 11.2, P = 0.797; US VS MR, X2 = 8.48, P = 0.903). Conclusion The main radiological characteristics of developmental anomalies of the right hepatic lobe were right lobe volume reduction, stenosis of the right portal vein, ectopic gallbladder, left lobe hypertrophy and dextral displacement of the first hepatic portal. By combining the data from imaging methods (CT, MRI, and US) with clinical data, developmental anomalies of the right hepatic lobe can be relatively accurately diagnosed. The results of this systematic comparative analysis may improve our understanding of this disease.