Hypothesis / aims of study
Complications from synthetic mesh which are transvaginal tape (TVT) and transobturator tape (TOT) inserted for female patients with stress urinary incontinence can be serious and debilitating. Surgery to remove the synthetic mesh may help to reduce or eliminate the complications. However, the surgery itself is high risk and carries its own complications. Furthermore, before proceeding with the surgery the surgeon needs to conclude that the signs and symptoms are genuinely caused by the synthetic mesh and not due to other pathological causes which may not be related to the mesh. The aim of this study is to devise an algorithm which is relevant for the diagnostic workup prior to mid-urethral sling removal surgery.
Study design, materials and methods
A closed loop audit was performed on patients who presented with complications that might be due to the insertion of TVT, TOT or both. Following discussion in a multi-disciplinary team meeting, patients were deemed suitable for mesh removal. Diagnostic investigations in addition to a careful history and physical examination, (abdominal, perineum and vaginal), included trans-labial ultrasound scan, MRI scan of pelvis, flexible cystoscopy and video-urodynamics. Data was collated and analyzed to identify a reliable, cost effective and time saving pathway which can provide the surgeon with salient findings to decide whether patient is suffering from mesh complications which may benefit with removal surgery or there are other pathological causes.
A total of 28 patients were included over a 4 year period, June 2014 to June 2018. 16 TVT mesh, 8 TOT mesh and 4 TVT and TOT meshes. Age range was 35 to 67 years old. Majority of patients, 57.1% (n=16) develop complications within 5 to 10 years of mesh insertion. 28.6% (n=8) had complications beyond 10 years, 3.6% (n=1) had complications as early as less than 5 years and 10.7% (n=3) were unsure of the duration of the mesh. Localized pain is the commonest complication, followed by urinary incontinence, dyspareunia, vaginal bleed, hematuria and recurrent urinary tract infections. 18 patients had MRI pelvis, 17 patients had flexible cystoscopy and trans-labial ultrasound and 8 patients had video-urodynamics.
Interpretation of results
A significant number of patients complained of complications that might be mesh related. Complications can develop as early as less than 5 years or even up to beyond 10 years of mesh insertion. Pain seems to be the most debilitating complication in majority of patients. The other complications varies and sometimes can be non-specific. Therefore, further investigation modalities were required which were MRI pelvis, trans-labial ultrasound, flexible cystoscopy and video-urodynamics.
This study will assist in choosing relevant pre-operative investigations prior to mid-urethral sling removal surgery. It is important to obtain a good history and to perform relevant physical examinations during the first encounter with patient. Vaginal examination helps exclude vaginal erosion and localizing the pain. In patients with pain and urinary tract infections, MRI of the pelvis and trans-labial ultrasound scanning are useful in looking at the position of the mesh and excluding other pathologies that may be contributing to the pain. Position of a TOT mesh are better seen on a trans-labial ultrasound than MRI of the pelvis. Both trans-labial ultrasound and MRI of the pelvis are useful in visualizing the TVT mesh. MRI pelvis was also noted to be useful to identify other causes of pain, for instant one of the patient was complaining of hip pain and it was actually due to arthritis of the hip joint instead of being caused by the mesh itself. For non-specific abdominal pain, computed tomography (CT) scan should also be performed. This was helpful for one patient who had her TVT mesh eroding into her small bowels which presented with collection in the retropubic region. Imaging modalities also assist the surgeon to trace the position of the mesh to allow complete removal. In patients with a suspected erosion into the urinary tract, e.g. with non-visible or visible hematuria, or recurrent urinary tract infections, a flexible cystoscopy is mandatory. Flexible cystoscopy can be performed locally before referring the patient to a tertiary referral center. Video-urodynamics can be limited to patients with a history of urinary incontinence prior to removal. The diagnosis obtained from the video-urodynamics with allow the surgeon to decide if patient needs other continent surgery such as autologous fascial sling, urethral bulking agent or colposuspension after the mesh removal. The continent surgery can be perform on the same setting as the removal surgery or at a later date. A thorough workup can also assist in reducing the number of mesh removal surgeries without any clear indication, resulting in reduced morbidity.