Clinically Oriented Classification of Anatomic Variants of the Umbilical Fissure for Ligamentum Teres in the Human Liver.

Background In the classic descriptions of the human liver, the umbilical fissure (UF) is a long, narrow groove on the visceral surface that receives the ligamentum teres hepatis. In this study, we document the UF variations encountered in a series of cadaveric dissections. Methods We reported UF variations using the following classification: Type I refers to "normal" anatomy where there is a long, narrow groove. In type II, the UF was covered by a fibrotic band devoid of hepatic parenchyma. In type III variants, an extension of hepatic parenchyma partially covered but did not obliterate the UF. In type IV variants, the hepatic parenchyma formed a bridge over the UF, completely obliterating the groove. After institutional review board approval, we observed all consecutive cadaveric dissections over five years and recorded the characteristics and dimensions of each UF and its immediate relations. Results There were 69 cadavers, and variant UFs were present in 38 (55.1%) cadavers: type II (1.5%), type III (20.3%), and type IV (33.3%). Conclusions In this Jamaican population, only 44.9% of persons had conventional "normal" anatomy and 55.1% had UF variants. These variants are clinically significant, as they lead to misinterpretation of patient imaging and can hinder operative procedures on the liver.