Evaluation of Deeply Infiltrating Endometriosis by Preoperative Magnetic Resonance Imaging in Patients with Adenomyosis

Before endometriosis surgery, it is important to identify deep infiltrating endometriosis (DIE) to assess the surgical difficulty. Preoperative magnetic resonance imaging (MRI) was used to determine which findings are useful in predicting DIE. Between 2008 and 2016, 54 patients with adenomyosis underwent total laparoscopic hysterectomy at our hospital. We retrospectively evaluated the intraoperative findings and magnetic resonance imaging (MR) images. The MR images were scored based on the presence of five findings: retroflexed uterus, elevated posterior vaginal fornix, intestinal tethering in the direction of the uterus, faint strands between the uterus and intestine, and fibrotic nodules covering the serosal surface of the uterus. Of the five findings, intestinal tethering and faint strands between the uterus and intestine showed a sensitivity of 73% and a specificity of 91%-100%, indicating the usefulness of these findings for detecting deep endometriosis lesions. However, finding a retroflexed uterus did not contribute to DIE lesion detection. The sensitivities of an elevated posterior fornix and fibrotic nodules covering the surface of the uterus were as low as 46%-59%, and their specificities were as high as 84%-91%. Preoperative preparation is essential for patients with intestinal tethering or faint strands between the uterus and intestine on preoperative MRI after obtaining appropriate informed consent.