From the Guidelines
Neuromodulation, specifically sacral neuromodulation (SNM), is the most effective treatment option for non-obstructive urinary retention when conservative measures have failed, with success rates ranging from 60-80%. This is based on the most recent and highest quality study available, which recommends SNM as a treatment option for patients with inadequate response to or intolerable side effects from pharmacotherapy or behavioral therapy 1. The procedure involves placing electrodes near the S3 sacral nerve to deliver mild electrical pulses that normalize communication between the bladder and brain.
Key Considerations
- Treatment typically begins with a test phase using a temporary lead to assess effectiveness before permanent implantation.
- Alternative neuromodulation approaches include percutaneous tibial nerve stimulation (PTNS), which requires weekly 30-minute sessions for 12 weeks, and pudendal nerve stimulation for patients who don't respond to SNM.
- Potential complications include infection, lead migration, and pain at the implant site.
- Battery replacement is typically needed every 3-7 years depending on stimulation parameters.
Patient Counseling
Patients should be counseled that while neuromodulation significantly improves symptoms in most cases, complete resolution of retention may not occur in all patients. The advantages and disadvantages of minimally invasive therapies, such as SNM and PTNS, should be discussed with patients to craft personalized treatment plans aligned with patient goals 1.
Evidence-Based Recommendation
The AUA/SUFU guideline on the diagnosis and treatment of idiopathic overactive bladder recommends offering sacral neuromodulation, tibial nerve stimulation, and/or intradetrusor botulinum toxin injection to patients with inadequate response to or intolerable side effects from pharmacotherapy or behavioral therapy 1. Although this guideline is specific to overactive bladder, the principles of neuromodulation can be applied to non-obstructive urinary retention, making SNM a viable treatment option for this condition.
From the Research
Neuromodulation for Non-Obstructive Urinary Retention
- Neuromodulation is a treatment modality that utilizes electrical stimulation to alter the function of an organ, and has been used to treat non-obstructive urinary retention 2, 3, 4, 5, 6.
- Sacral neuromodulation (SNM) is a common modality for bladder neuromodulation, which involves stimulation through the S3 foramen, and has been shown to be effective in treating non-obstructive urinary retention 2, 3, 4, 5, 6.
- Percutaneous tibial nerve stimulation (PTNS) is another method of neuromodulation that has been used to treat non-obstructive urinary retention, and has the advantage of being a minimally invasive office-based procedure 3, 5, 6.
Efficacy of Neuromodulation
- Studies have shown that sacral neuromodulation can improve symptoms of non-obstructive urinary retention, with a significant decrease in post-void residual volume (PVR) and an increase in voided volume 4.
- The overall success rate of sacral neuromodulation ranges from 43% to 85%, while the success rate of PTNS ranges from 40% to 79.5% 6.
- Neuromodulation has been shown to be a durable and effective treatment for non-obstructive urinary retention, with few associated complications 4, 5, 6.
Complications and Limitations
- Sacral neuromodulation has a higher incidence of complications compared to PTNS, due to the more invasive surgical technique and the presence of a permanent implant 6.
- The most frequent complications with sacral neuromodulation include pain at the implant site, lead migration, pain at the lead site, leg pain, and infection 6.
- The quality of studies on sacral neuromodulation and PTNS is modest, with a shortage of good randomized clinical trials, and most studies being prospective observational studies with mid-term follow-up 6.