腹膜转移瘤的MRI诊断

目的探讨腹膜转移瘤(pefitoneal carcinomatosis,PC)的MRI表现特征,重点探讨DWI对PC的诊断价值。方法49例经临床或病理检查确诊PC,MRI检查包括T_1WI、T_2WI、DWIBS和增强3D THRIVE序列,由两位经验丰富的影像医师回顾性分析其MRI表现,并将腹膜腔肿瘤的分布、大小及DWI信号强度进行观察并记录,如意见不同,通过讨论达成一致。结果 PC的MRI表现:壁层、脏层腹膜线状增厚4例、不规则线状增厚35例、肠道表面浆膜增厚11例;大、小网膜污垢状增厚22例、饼状增厚14例;肠系膜污垢样改变12例;腹膜腔软组织结节、肿块46例、囊陛肿块6例;其他表现:腹腔积液45例、腹部原发癌灶25例、腹部淋巴结肿大12例。本组腹膜腔共有348个部位受累,经双变量相关分析统计,KendaN相关系数为0.438,Spearman相关系数为0.473,均为P0.001,提示病灶大小与DWI信号强度呈正相关关系,但相关关系并不密切(相关系数小于0.5)。结论 MRI能显示PC及其范围,同时检出其腹部原发癌灶,充分认识其MRI表现,不难对PC做出准确的诊断。DWI有助于PC灶的检出。

MRI diagnosis of peritoneal carcinomatosis

Objective To study the MRI feature of peritoneal carcinomatosis and to evaluate the diagnostic value of diffusion-weighted imaging（DWI）.Methods MRI of 49 patients with peritoneal carcinomatosis confirmed by surgery and pathology was reviewed.The MRI sequences included T1-,T2-,diffusion-weighted,and gadolinium-enhanced 3D THRIVE sequences.The distribution,size and DWI signal intensities of the tumors were graded by two radiologists in consensus.Results Of 348 sites of peritoneal carcinomatosis,the imaging findings included linear thickening of parietal and visceral peritoneum（4）,irregular linear thickening（35）,serosal thickening of the intestinal surface（11）,omental stranding（22）and caking（14）,mesentery stranding （12）,nodules and masses in the abdominal cavity（46）,cystic masses（6）,ascites（45）,primary abdominal carcinoma（25）and lymphadenopathy（12）.Bivariate correlation analysis showed weak correlation between the size and DWI signal intensities（Kendall correlation coefficient=0.438;Spearman correlation coefficient=0.473）.Conclusion MRI with DWI can depict the primary abdominal carcinoma and extent of peritoneal carcinomatosis.