Wright F W
Clin Radiol. 1977 Jul;28(4):469-73. doi: 10.1016/s0009-9260(77)80167-0.
Gas within clefts of fissures in gallstones is not a very common finding, but when it occurs is, characteristic and indicates the presence of one or more calculi. It closely resembles the appearance of a 'Jack Stone' but has previously been termed the 'Mercedes Benz' sign. Only a few cases have previously been recognised in the U.K. Most reported cases have been associated with biliary colic or cholecystitis. Various theories have been put forward to explain the presence of gas, but the author believes that the gas is released from solution by negative pressure within cholesterol stones undergoing internal fissuring due to their crystalline structure, i.e. the gas is released from solution from the small amount of fluid trapped in the calculus, in the same way that gas may be 'pulled' out of solution in a joint, a degenerate intervertebral disc or the fibro-cartilage of the symphysis pubis.
胆结石裂隙内的气体并非常见表现，但一旦出现则具有特征性，提示存在一个或多个结石。它与“杰克石”的外观极为相似，但此前被称为“梅赛德斯 - 奔驰”征。在英国，此前仅识别出少数病例。大多数报告病例与胆绞痛或胆囊炎有关。关于气体的存在，人们提出了各种理论，但作者认为，由于胆固醇结石的晶体结构，其内部发生裂隙时产生的负压使气体从溶液中释放出来，即气体是从结石中捕获的少量液体的溶液中释放出来的，就像气体可能从关节、退变的椎间盘或耻骨联合的纤维软骨中的溶液中“吸出”一样。
