Kalota recommends initial third line treatment with PTNS, and she actually considers PTNS, “level 2.5” treatment, with BTX and SNS as “level 3” treatment. Her reasoning for early treatment with PTNS is that it is easy to perform, minimally invasive, has minimal adverse events, and has level 1 evidence to support it as a treatment modality.2 The typical treatment strategy, as described in the literature, is to do weekly sessions for 12 weeks. Kalota shared that she starts with 6 treatment sessions before patients have a follow up appointment to evaluate their progress. If a patient has no benefit at all, treatment is stopped and he or she can progress to other treatments. If there is some benefit they complete the remaining 6 treatments and then have another follow up appointment. After 12 visits patients will move on to maintenance therapy with monthly treatments and follow up yearly. Kalota notes that some patients require more frequent maintenance, and this is usually not covered by insurance. In these patients, she will consider SNS. Barriers to treatment with PTNS include high office copays and a considerable time commitment. It was noted by Kenneth Peters, MD that in the randomized control study it took 10 treatments to differentiate the outcomes between sham and treatment groups, so stopping treatments after 6 weeks may not give patients the full potential outcomes from PTNS.
When patients have minimal or no benefit from PTNS, BTX or SNS can be considered. Kalota performs injection of BTX in the office or operating room. 100 units is used for initial injection in non-catheterizing patients, and 200 units in catheterizing patients. The first visit following injection occurs in two weeks for all patients, and a PVR is checked. If PVR is low or reasonable next follow up occurs at 1 month and PVR is checked again. Patients who have a good treatment response and low PVR at one month have the next follow up when the improvement wears off. If they are not doing better and have a small PVR they are scheduled for a higher dose injection at 3 months after the first procedure. If they are not doing better and have an elevated PVR clean intermittent catheterization is initiated. Kalota notes that some patients may require doses of less than 100 units, while some patients will have ideal dosing between 100 and 200 units.
SNS is another option for third line therapy in patients who have failed more conservative treatment. Kalota has found lower success rates with peripheral nerve evaluation (PNE) than staged implant approach and performs staged implantation exclusively. Patients are seen in follow up at one week after stage 1 lead placement. For patients who meet criteria for stage 2, they have the option to continue the trial to week 2 versus cutting the percutaneous lead extension and discontinuing the trial. Patients who go on to stage 2 implantation are followed up at two weeks, and then yearly after that. Advantages of SNS include its efficacy in the treatment of urinary retention and fecal incontinence, unlike other third line therapies.
Overall, the choice of third line therapy will depend on patient characteristics and patient acceptance after a thorough risk and benefit discussion. Kalota provided a practical approach for decision-making in third line therapy that will work for many clinicians and patients.
Presented by: Susan Kalota, MD; Tucson, AZ
Co-Authors: Kenneth Peters, MD
1. Gormley EA, Lightner DJ, Burgio KL, et al. Diagnosis and Treatment of Overactive Bladder (Non-Neurogenic) in Adults: AUA/SUFU Guideline. J Urol. 2012;188(6):2455-2463. doi:10.1016/j.juro.2012.09.079
2. Peters KM, Carrico DJ, Perez-Marrero RA, et al. Randomized Trial of Percutaneous Tibial Nerve Stimulation Versus Sham Efficacy in the Treatment of Overactive Bladder Syndrome: Results From the SUmiT Trial. J Urol. 2010;183(4):1438-1443. doi:10.1016/j.juro.2009.12.036
Written by: Dena Moskowitz, MD; Fellow, Female Pelvic Medicine and Reconstructive Surgery, Virginia Mason Medical Center; @demoskowitz at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA