Introduction 
Synthetic mesh for treatment of stress urinary incontinence can be associated with exposure into the vagina and extrusion into the urinary tract (1).  Magnetic resonance imaging (MRI) and ultrasound imaging using the trans-rectal (TRUS) or transvaginal approach can diagnose some mesh complications and contribute to the diagnostic pathway for women alongside examination under anaesthesia and cysto-urethroscopy. 

Aims of study 
The aim of this retrospective study is to assess the diagnostic accuracy of MRI and TRUS in detecting mesh complications amongst our cohort of women. 

At this present time, there is limited evidence regarding the efficacy of TRUS, and with little to no published data regarding MRI (2).

A retrospective analysis was performed of all women who had surgical removal of continence mesh or a formal examination under anaesthetic in our Urology unit from 2018 to 2021. MRI and TRUS imaging reports were compared to ‘gold standard’ definitive diagnosis in theatre to determine the detection rate of vaginal exposure, urethral and bladder extrusion of each imaging modality.

Forty eight patients had mesh removal surgery or a formal examination under anaesthesia for mesh complications in this timeframe. Eight women had vaginal mesh exposure, sixteen had urethral extrusion and seven had bladder extrusion detected. Thirty seven women had pre op MRI imaging, twenty five had TRUS. Twenty four women had both MRI and TRUS. Eight women with vaginal exposure at surgical exploration in theatre, had both TRUS and MRI preoperatively with a detection rate of TRUS of 2/6 (33.3%) and MRI of 2/8 (25%).

TRUS and pelvic MRI showed similar detection rates of 71.4% and 80% respectively in the diagnosis of urethral extrusion. Amongst the 5 women with bladder extrusion who had TRUS, detection rate was 1/5 (20%). In contrast, MRI detected 5/6 cases of bladder extrusion. There were no ‘false positive’ MRIs or TRUS findings.

TRUS and MRI imaging can detect mesh complications but they cannot replace direct visualisation with examination or cystoscopy. In our cohort of female patients, MRI performed well in the detection of bladder and urethral extrusion. TRUS performed similarly well in detecting urethral extrusion. Neither TRUS or MRI imaging modality was reliable in the detection of vaginal exposure.  

This study is limited by its selected surgical cohort and therefore it excludes some women with mesh complications. Future prospective analysis of all women having investigations for mesh complications, will allow for more accurate sensitivity as well as specificity calculations.

Keltie K, Elneil S, Monga A, Patrick H, Powell J, Campbell B, Sims AJ. Complications following vaginal mesh procedures for stress urinary incontinence: an year study of 92,24women. Sci Rep. 201Sep 20;7(1):1201doi: 10.1038/s41598-017-11821-w. PMID: 28931856; PMCID: PMC5607307.
Duckett J, Thakar R, Shah V, Stephenson J, Balachandran A. The Use of Imaging for Synthetic Midurethral Slings. J Ultrasound Med. 202Aug;39(8):1497-150doi: 10.1002/jum.1525Epub 202Mar PMID: 32125008.