Gallbladder torsion is a rare disorder occurring when the gallbladder twists along its axis and only approximately 500 cases have been reported in the English literature [1,2]. Preoperative diagnosis is difficult due to similar signs and symptoms and image findings as other acute cholecystitis [3]. Emergent cholecystectomy is the preferred treatment in most cases. However, delays in treatment may result in poor prognosis and a high mortality rate because of gallbladder ischemia, necrosis, and perforation [4]. We herein report two cases of gallbladder torsion which was difficult to diagnose preoperatively and was confirmed intraoperatively and treated successfully with laparoscopic cholecystectomy.

Gallbladder torsion is rare and occurs secondary to the twisting of the gallbladder on its mesentery. Anatomical variation is thought to play a role in its pathogenesis, with an abnormally long mesentery joining the gallbladder to the liver, resulting in a free-hanging or “floating gallbladder,” which was first described by Wendel [5] in 1898. The highest incidence of gallbladder torsion occurs in the elderly population, with 85% of cases occurring in people between the ages of 60 and 80 years old [6]. Adult women are reportedly more affected than men, with a 3:1 female to male ratio [4]. The etiology of gallbladder torsion is not entirely clear, but there are two common predisposing anatomical factors: a wide mesentery that support cystic duct and artery, and a small liver bed of the gallbladder that can flat the gallbladder freely. These variations allow the rotation of the gallbladder along its long axis, causing vascular compromise due to ischemic compression of the cystic artery. Torsion is classified as complete, which is ≥180° of rotation, and incomplete, <180° of rotation [7].

Gallbladder torsion is a separate entity that can mimic other causes of cholecystitis. Gallbladder torsion is difficult to diagnose [8], but if treated according to acute cholecystitis, an urgent situation can be avoided. However, in most cases like our first case, when the initial signs and symptoms were not clear likewise other acute cholecystitis, the operation could be delayed due to suspicion of another disease [9]. And in the majority of cases, the patient is older and has many underlying diseases, acalculous cholecystitis can be often managed non-operatively with a growing trend toward percutaneous cholecystostomy as the initial and sometimes definitive management [4]. However, in cases of gallbladder torsion, conservative treatments such as intravenous antibiotics and percutaneous cholecystostomy could be ineffective and result in even fatal. Hence, preoperative diagnosis is important as it requires urgent surgical management.

Preoperative CT and MRCP findings and imaging such as ultrasound and CT are often obtained yet rarely reveal the diagnosis of gallbladder torsion. CT imaging findings suggestive of possible gallbladder torsion include a fluid collection between the gallbladder and the gallbladder fossa of the liver, a horizontal arrangement of the long axis of the gallbladder, a well-enhanced cystic duct located on the right side of the gallbladder, and signs of inflammation such as edema and gallbladder wall thickening [3,10]. MRCP imaging findings may aid in the preoperative diagnosis of gallbladder torsion by showing a V-shaped distortion of the extrahepatic bile ducts due to a twisting of the cystic duct. Additionally, a high-intensity signal on T1-weighted images within the gallbladder wall could indicate a possible infarction [3]. Other studies report a “cystic duct knot sign” on ultrasonography and a CT finding of a “whirl sign” in cases reported cases of gallbladder torsion [10]. Our patient exhibited a distended gallbladder with possible wall thickening and a dilated and redundant gallbladder on CT imaging. However, a diagnosis of gallbladder torsion was not suspected based on these imaging findings alone and the definitive diagnosis of gallbladder torsion was not made until surgery. Once identified, diagnosis and treatment via laparoscopy or laparotomy should result in prompt detorsion and cholecystectomy.

In conclusion, torsion of the gallbladder is a rare but clinically important condition that is primarily seen in elderly women. Current imaging modalities are unreliable for obtaining a preoperative diagnosis. However, this diagnosis must be considered in the differential of elderly women patients with signs and symptoms of acalculous cholecystitis with the absence of biliary stones and a free-floating gallbladder.