Gallbladder fossa volume decreased in livers without gallbladders: A cadaveric study.

The gallbladder normally lies within a fossa on the visceral surface of the liver. The primary purpose of this study was to determine whether the volume of this fossa was reduced after cholecystectomy. Livers were obtained from embalmed cadavers of 19 females and 15 males with a mean age of 84.1 ± 10.8 yrs. The presence of a gallbladder was assessed, the volume of the irregularly-shaped gallbladder fossa determined from a mold of the fossa, and the dimensions of each fossa were estimated. The mean volume of gallbladder fossae from livers with gallbladders (n = 26; 13 females and 13 males) was 31.01 ± 17.82 ml, which was significantly greater than fossae in livers without gallbladders (n = 8, 6 females, 2 males) which was 8.75 ± 4.72 ml (P<0.0001). This difference still was significant after correcting fossa volume for overall liver weight and length of the femur. Livers with gallbladders had significantly larger dimensions (depth, length, and width) of their fossae molds than did livers without gallbladders (P<0.05). The largest percentage difference between the two groups in these dimensions was in the fossae depth, and there was a significant, positive correlation between all three of these dimensions and the overall volume of the fossae. Even looking only at female livers which tend to be smaller, gallbladder fossa volume was reduced in livers without a gallbladder. Thus, the present study demonstrated that the mean gallbladder fossa volume was significantly decreased in livers lacking gallbladders, even after correcting for the liver weight and size of the individual. While the mechanisms behind these changes in fossa volume currently are unknown, alterations in mechanical pressure relayed to adjacent liver cells after gallbladder removal may play a role in these fossa volume differences.