Que Yanhong, Wang Xuemei, Liu Yanjun, Li Ping, Ou Guocheng, Zhao Wenjing
Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China.
Eur J Radiol. 2009 May;70(2):331-5. doi: 10.1016/j.ejrad.2008.01.036. Epub 2008 Mar 6.
Thickened greater omentum is encountered with high frequency in patients with ascites. The purpose of our study was to assess the utility of greater omentum biopsy under the guidance of ultrasound (US) in tracing the origin of unclear ascites and differentiating benign and malignant ascites.
We retrospectively reviewed our institutional database for all records of greater omentum biopsy cases. One hundred and ninety-four patients with unclear ascites and thickened greater omentum were included in the study. The sonograms of greater omentum were evaluated before undergoing the ultrasound-guided biopsy and a biopsy was considered successful if a specific benign or malignant diagnosis was rendered by the pathologist.
Successful biopsy was rendered for 182 biopsy procedures (93.8%, 182/194) including tuberculosis (n=114), chronic inflammation (n=3), metastases (n=58), malignant mesothelioma (n=6) and pseudomyxoma peritonei (n=1). Twelve biopsies were non-diagnostic. According to the results of biopsy and follow-up, the sensitivity and specificity of biopsy in distinguishing malignant ascites from benign ascities were respectively 95.6% (65/68) and 92.9% (117/126). The greater omentum of 84 cases of tuberculous peritonitis showed "cerebral fissure" sign and was well seen as an omental cake infiltrated with irregular nodules when involved by carcinomatosis. No "cerebral fissure" sign was observed in peritoneal carcinomatosis. The sensitivity and specificity of this sign in indicating the existence of tuberculous peritonitis were 73.5% (89/121) and 100% (73/73). Moreover, if the specific "cerebral fissure" sign was combined with the biopsy results, the specificity of biopsy in distinguishing malignant ascites from benign ascits increased to 96.8% (122/126).
Ultrasound-guided biopsy of greater omentum is an important and effective method to diagnose the unclear ascites for patients with thickened omentum if certain techniques could be paid attention to. "Cerebral fissure" sign of greater omentum was a specific sign in indicating the tuberculous peritonitis and could increase the specificity of biopsy in distinguishing malignant ascites from benign ascits if combined with the biopsy results.
腹水患者大网膜增厚的情况较为常见。本研究旨在评估超声引导下大网膜活检在追查不明原因腹水的来源以及鉴别良性和恶性腹水方面的效用。
我们回顾性分析了本机构数据库中所有大网膜活检病例的记录。194例不明原因腹水且大网膜增厚的患者纳入本研究。在进行超声引导下活检前评估大网膜的超声图像，若病理学家做出明确的良性或恶性诊断，则认为活检成功。
194例活检操作中有182例（93.8%，182/194）活检成功，包括结核病（n = 114）、慢性炎症（n = 3）、转移瘤（n = 58）、恶性间皮瘤（n = 6）和腹膜假黏液瘤（n = 1）。12例活检未得出诊断结果。根据活检及随访结果，活检鉴别恶性腹水与良性腹水的敏感性和特异性分别为95.6%（65/68）和92.9%（117/126）。84例结核性腹膜炎患者的大网膜表现为“脑沟”征，当发生癌性腹膜炎时，大网膜呈伴有不规则结节浸润的网膜饼状，清晰可见。癌性腹膜炎未观察到“脑沟”征。该征象提示结核性腹膜炎存在的敏感性和特异性分别为73.5%（89/121）和100%（73/73）。此外，若将特定的“脑沟”征与活检结果相结合，活检鉴别恶性腹水与良性腹水的特异性提高至96.8%（122/126）。
如果注意某些技术要点，超声引导下大网膜活检是诊断大网膜增厚患者不明原因腹水的重要且有效方法。大网膜“脑沟”征是提示结核性腹膜炎的特异性征象，若与活检结果相结合，可提高活检鉴别恶性腹水与良性腹水的特异性。
