Abstract

Background: Gallbladder mucocele (GBM) is an increasingly recognized cause of extrahepatic biliary disease in dogs, but the optimal timing of surgical referral remains poorly defined, and published guidance on preoperative diagnostic criteria and combined surgical approaches is limited.
Case presentation: We describe two dogs referred for progressive icterus, vomiting, and abdominal discomfort. Case 1 was a two-year-old intact male Spitz; Case 2 was a ten-year-old neutered male mixed Pomeranian with concurrent diabetes mellitus. Serial complete blood counts and serum biochemistry demonstrated cholestatic liver enzyme patterns (elevated alkaline phosphatase and gamma-glutamyl transferase with hyperbilirubinemia), and abdominal ultrasonography identified a stellate (Case 1) and kiwi-like (Case 2) gallbladder mucosal pattern consistent with GBM. Both dogs were stabilized medically for one week before cholecystectomy was performed through a combined right subcostal-midline incision, which we found to provide wider intraoperative exposure of the extrahepatic biliary tree than either approach used alone. Histopathology confirmed mucocele with hydropic degeneration, ischemic necrosis, and epithelial hyperplasia in both cases. Liver enzyme activities and total bilirubin concentrations declined after surgery, and gastrointestinal signs resolved in both dogs during a six-month follow-up period.
Conclusions: In these two dogs, a structured preoperative work-up combining serial biochemistry with ultrasonographic staging supported timely surgical referral, and a combined subcostal-midline approach allowed adequate exposure for cholecystectomy without intraoperative rupture. These observations should be interpreted as descriptive findings from two cases rather than generalizable evidence, and further comparative studies are needed to evaluate this combined approach against standard techniques.

Key words: bile duct, cholecystectomy, gallbladder, mucocele