Bowel wall thickness measured by MRI is useful for early diagnosis of bowel endometriosis.

OBJECTIVE: To evaluate MRI features of bowel endometriosis (BE) and verify its clinical significance compared with pathological diagnosis. MATERIALS AND METHODS: Since 2018, patients clinically diagnosed with deep endometriosis (DE) and planned to undergo surgery were enrolled prospectively. MRI parameters including traction, thickening sign of the rectum, obliteration of the Douglas Pouch, sign of adenomyosis, and pelvic adhesion were extracted. Uni- and multi-variate analyses were performed to explore their association with pathological diagnosis of BE. ROC curve was utilized to ascertain the appropriate cutoff value for predicting the presence and assessing the severity of BE. RESULTS: A total of 226 patients with DE were recruited, and 154 BE cases were pathologically confirmed. Logistic regression analysis revealed that thickness of the rectal wall, traction sign of the rectum, and obliteration of the Douglas Pouch were independent factors to predict the presence of BE with the OR 1.59 (95% CI: 1.29-1.96), 0.24 (95% CI: 0.09-0.67), and 0.17 (95% CI: 0.07-0.40), respectively (p all < 0.01). A cutoff value of 6.0 mm for the thickness of rectal wall resulted in the highest predictive value of BE (specificity: 90.3%; sensitivity: 78.6%). For patients with measured thickness of the rectal wall over 6.0 mm, 72.1% (93/129) was confirmed BE with lesions infiltrated more than muscular layer. CONCLUSION: This prospective study indicates that based on precise definition of visualized features on MRI images, BE could be recognized pre-operatively. DE patients with thickness of rectal wall exceeding 6.0 mm have a greater probability of BE. CLINICAL RELEVANCE STATEMENT: Based on precise definition of visualized features and accurate measurement on MRI images, bowel infiltrating among deep endometriosis patients could be recognized pre-operatively. KEY POINTS: • Precise definition of measurable MRI parameters made it possible for early detection of bowel endometriosis. • Thickening sign, traction sign of the rectum, and obliteration of the Douglas Pouch were typical radiological indicators for bowel endometriosis. • Bowel involvement is more sensitive to be detected among pelvic deep endometriosis patients with the thickness of the rectal wall over 6.0 mm.

MR findings of primary ovarian granulosa cell tumor with focus on the differentiation with other ovarian sex cord-stromal tumors.

BACKGROUND: To describe magnetic resonance imaging (MRI) features of ovarian granulosa cell tumors (OGCTs) and compare with other sex cord-stromal tumors (OSCs) in ovary. METHODS: MR findings of 18 patients with surgically confirmed ovarian granulosa cell tumor were retrospectively reviewed by two radiologists with consensus reading. All MR examinations were prospectively performed within one month. Clinical and imaging characteristics of OGCTs were evaluated and compared with OSCs (control group). RESULTS: In 18 patients, 20 ovarian granulosa cell tumors were detected on MRI. Sixteen tumors appeared as solid or mostly solid mass (16/20), while 4 tumors as cystic mass. Pathological pelvic fluid was detected in 1 OGCT (1/18) and 11 OSCs (11/34) (p = 0.031).On T2 weighted imaging (T2WI), most of OGCTs displayed hyperintense signal and mixed signal (19/20); on T1 weighted imaging (T1WI), 11 OGCTs (11/20) displayed similar signal as on T2WI imaging. The lesion signal between OGCT and OSC differed significantly on both T1WI (p = 0.017) and T2WI (p = 0.002). Tumoral bleeding was detected in 6 OGCTs on MRI. On diffusion weighted imaging (DWI) images, OGCTs mostly appeared as high signal (16/20). Average apparent diffusion coefficient (ADC) value derived from DWI images in the OGCT group (0.84 ± 0.26× 10- 3 mm2/s was less than the control group (1.22 ± 0.47 × 10- 3 mm2/s) with statistical difference (p = 0.002). CONCLUSIONS: MRI could provide important information in OGCT diagnosis. ADC value might be useful in differentiating OGCT from OSC.

Rectovaginal fistula following surgery for deep infiltrating endometriosis: Does lesion size matter?

Objective This study was performed to identify risk factors for postoperative rectovaginal fistula (PRF) in patients with deep infiltrating endometriosis (DIE). Methods Data were retrospectively obtained from the medical records of 104 patients with DIE, and statistical analysis was used to detect risk factors for PRF. Results Five of 104 (4.8%) patients developed PRF from 5 to 16 days postoperatively. The operative procedures included 84 (80.8%) superficial excisions, 6 (5.8%) full-thickness disc excisions, and 14 (13.5%) bowel resections. Most lesions were located in the cul-de-sac, and the mean lesion size was 2.6 cm (range, 0.5-7.0 cm). The univariate analysis showed that lesion location, larger lesion size, and surgical technique were statistically significant risk factors for PRF. Conclusion Surgical procedures should be very carefully executed in patients with DIE lesions of ≥4 cm.