MRI diagnosis of rectosigmoid endometriosis

Objective To investigate the MRI features of endometriosis involving the rectum and sigmoid colon. Methods MRI of 53 pathologically proved deep pelvic endometriosis involving the rectum and sigmoid colon was analyzed respectively and correlated with clinical, operative and pathological findings. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value of MRI were calculated. Results Focal thickening of the rectosigmoid wall was seen in 47 patients with T1 isointensity,T2hypointensity and slight contrast enhancement. The pouch of Douglas was narrowed or obliterated by plaquelike(22), nodular(18) or stripe-like(13) abnormal signal intensities. Other features included retroflexed uterus(35), anterior displacement of rectosigmoid angle(20) and posterior superior traction of the posterior vaginal fornix(15). The MRI diagnostic accuracy,sensitivity, specificity, positive predictive value and negative predictive value were 93.65%, 96.23%, 80.00%, 96.23% and 80.00%,respectively. Conclusion MRI features are diagnostic in rectosigmoid endometriosis.