间位网膜的认识及其临床意义

Cognizance of interpositional omentum and clinical significance

目的对间位网膜进行描述，阐述其临床意义。方法查阅CT资料及临床资料，对肝上间隙增宽的病例，调整CT对比度进一步观察，并查阅其相关的临床资料进行分析。结果在1916例上腹部CT资料中，肝上间隙增宽者共152例，呈脂肪样密度者119例。119例患者中外伤3例，急腹症3例，余无外伤史及急腹症表现。单纯阅读CT片提示膈下游离气体，调整对比度后显示为膈下脂肪样密度。11例行手术治疗，其中1例乙状结肠破裂、4例肝硬化并门脉高压症、3例胃癌、1例急性胆囊炎、1例胆管癌及1例先天性胆总管囊性扩张症，术中均发现大网膜反折覆盖于肝上间隙。余108例未行手术治疗。结论间位网膜是大网膜移位至肝上间隙，覆盖肝膈面的临床现象，临床并非罕见。本组资料统计其发生率为6．21％（119／1916）；发病机制可能类似于间位结肠；腹部CT平扫时与膈下积气难以鉴别，调整CT对比后易于区别，避免误认为膈下游离气体行不必要的手术探查。

Objective To describe the interpositional omentum and demonstrate its clinical significance. Methods CT and clinical data of the cases whose suprahepatic gaps widen were reviewed and the contrast of CT was adjusted to observe further. Results In 1 916 cases with upper abdominal CT data, suprahepatic gap was widen in all 152 cases, and 119 cases showed fat density（6.21% ）. There were 3 cases of trauma and 3 cases of acute abdomen in the 119 cases CT in the 119 cases displayed free gas under diaphragma, but displayed fat density after contrast adjusted. There were 11 cases undergoing operations, 1 for sigmoid rupture 4 liver cirrhosis and portal hypertension, 3 gastric cancer, and 1 acute cholecystitis, 1 bile duct carcinoma and 1 case congenital cystic dilata- tion of common bile duct. The other 108 cases did not undergo surgical operation. Conclusions Interpositional omentum is a clinical phenomenon that the omentum was shift in suprahepatie gap covering the liver surface. It is not rarely, the incidence rate being 6.21% （ 119/1 916） in our study. The occurrence mechanism may be similar to that of Chi]aiditi syndrome. It is difficult to differentiate interpositional omentum from free gas under diaphragma on CT plain scan picture, but it is easy after contrast adjusted of CT. Free gas under diaphragma should not be identify incorrectlied and patients should not undergo unnecessary surgical procedure.