Pascal Rousset1, Elodie Bischoff2, Mathilde Charlot2, Flavia Grangeon3, Gil Dubernard4, Philippe Paparel5, Jean-Christophe Lega6, François Golfier7. 1. Lyon 1 Claude-Bernard University, EMR 3738, Hospices Civils de Lyon, Lyon Sud University Hospital, Department of Radiology, 69495 Pierre-Bénite, France. Electronic address: roussetpascal@gmail.com. 2. Hospices Civils de Lyon, Lyon Sud University Hospital, Department of Radiology, 69495 Pierre-Bénite, France. 3. Lyon 1 Claude-Bernard University, EMR 3738, Hospices Civils de Lyon, Lyon Sud University Hospital, Department of Radiology, 69495 Pierre-Bénite, France. 4. Lyon 1 Claude-Bernard University, LabTAU, Hospices Civils de Lyon, Croix-Rousse Hospital, Obstetrics and Gynaecology Department, 69004 Lyon, France. 5. Lyon 1 Claude-Bernard University, Hospices Civils de Lyon, Lyon Sud University Hospital, Urology Department, 69495 Pierre-Bénite, France. 6. Lyon 1 Claude-Bernard University, UMR CNRS 5558, Hospices Civils de Lyon, Lyon Sud University Hospital, Internal and Vascular Medicine Department, 69495 Pierre-Bénite, France. 7. Lyon 1 Claude-Bernard University, EMR 3738, Hospices Civils de Lyon, Lyon Sud University Hospital, Gynecological Oncological, and Obstetrics Department, 69495 Pierre-Bénite, France.
Abstract
PURPOSE: The purpose of this study was to retrospectively evaluate the performance of magnetic resonance imaging (MRI) in locating endometriosis implants within the bladder wall with assessment of ureteral orifice extension using surgical findings as standard of reference. MATERIALS AND METHODS: MRI examinations of 39 consecutive women (mean age: 31.2±5.5 [SD] years; age range: 22-42years) operated in 3 university hospitals for bladder endometriosis over a 6-year period were reviewed by 2 independent readers. Interobserver agreement was assessed using Kappa tests. Results of consensus reading were used to calculate sensitivity, specificity and accuracy of MRI for the diagnosis, location and extent of endometriosis implants using surgical findings as the standard of reference. RESULTS: Mean bladder repletion volume was 134±110 [SD] mL (range: 21-479mL). The mean largest endometriosis implant diameter was 30±7 [SD] mm (range: 19-41mm). On MR images, 34/39 (87%) endometriosis implants were present in the two anterior thirds of the dome (k=0.45), 31/39 (79%) extended or were present in the posterior third pouch (k=0.92) and 25/39 (64%) extended into the bladder base (k=0.84) with sensitivities of 100% (31/31; 95% confidence interval [CI]: 89-100%), 100% (30/30; 95% CI: 88-100%) and 90% (19/21; 95% CI: 69-98%), respectively, specificities of 83% (5/6, 95% CI: 36-100), 88% (7/8, 95% CI: 47-100%), 87% (13/15; 95% CI: 52-96), respectively and accuracies of 97% (36/37, 95% CI: 86-100%), 97% (37/38; 95% CI: 86-100%), and 89% (32/36; 95% CI: 74-97%), respectively. In 9 (9/25; 36%) patients with bladder base involvement, a zero distance was reported between endometriosis implants and ureteral orifices, all but one presenting with low-to-moderate bladder volumes. In the two patients who needed ureteral resection-reimplantation, ureteral dilation was associated with a zero distance. External adenomyosis was reported in 26/39 (66%) patients (k=0.94). CONCLUSION: A dedicated preoperative MRI work-up for bladder endometriosis helps accurately depict and locate endometriosis implants. Adequate bladder filling is needed to improve appropriate estimate of the distance between endometriosis implants and ureteral orifices to better predict requirement of ureteral resection-reimplantation.
PURPOSE: The purpose of this study was to retrospectively evaluate the performance of magnetic resonance imaging (MRI) in locating endometriosis implants within the bladder wall with assessment of ureteral orifice extension using surgical findings as standard of reference. MATERIALS AND METHODS: MRI examinations of 39 consecutive women (mean age: 31.2±5.5 [SD] years; age range: 22-42years) operated in 3 university hospitals for bladder endometriosis over a 6-year period were reviewed by 2 independent readers. Interobserver agreement was assessed using Kappa tests. Results of consensus reading were used to calculate sensitivity, specificity and accuracy of MRI for the diagnosis, location and extent of endometriosis implants using surgical findings as the standard of reference. RESULTS: Mean bladder repletion volume was 134±110 [SD] mL (range: 21-479mL). The mean largest endometriosis implant diameter was 30±7 [SD] mm (range: 19-41mm). On MR images, 34/39 (87%) endometriosis implants were present in the two anterior thirds of the dome (k=0.45), 31/39 (79%) extended or were present in the posterior third pouch (k=0.92) and 25/39 (64%) extended into the bladder base (k=0.84) with sensitivities of 100% (31/31; 95% confidence interval [CI]: 89-100%), 100% (30/30; 95% CI: 88-100%) and 90% (19/21; 95% CI: 69-98%), respectively, specificities of 83% (5/6, 95% CI: 36-100), 88% (7/8, 95% CI: 47-100%), 87% (13/15; 95% CI: 52-96), respectively and accuracies of 97% (36/37, 95% CI: 86-100%), 97% (37/38; 95% CI: 86-100%), and 89% (32/36; 95% CI: 74-97%), respectively. In 9 (9/25; 36%) patients with bladder base involvement, a zero distance was reported between endometriosis implants and ureteral orifices, all but one presenting with low-to-moderate bladder volumes. In the two patients who needed ureteral resection-reimplantation, ureteral dilation was associated with a zero distance. External adenomyosis was reported in 26/39 (66%) patients (k=0.94). CONCLUSION: A dedicated preoperative MRI work-up for bladder endometriosis helps accurately depict and locate endometriosis implants. Adequate bladder filling is needed to improve appropriate estimate of the distance between endometriosis implants and ureteral orifices to better predict requirement of ureteral resection-reimplantation.