June 22, 2024
Global Sacral Nerve Stimulation

Is sacral nerve stimulation right for your overactive bladder or fecal incontinence?

What is it?

Sacral nerve stimulation or SNS is a type of neuromodulation therapy that involves stimulating certain sacral nerves in the lower back. These sacral nerves control bladder, bowel and sexual function. In SNS therapy, a thin wire lead is placed near the sacral nerves through a minimally invasive surgical procedure. A neurostimulator is then placed under the skin near the buttocks to deliver mild electrical pulses to these sacral nerves. The pulses disrupt the abnormal signals from the bladder or bowel to the brain that cause symptoms of overactive bladder or fecal incontinence. This helps restore normal bladder or bowel control.

How does it work for overactive bladder?

Overactive bladder is a condition characterized by symptoms like frequent urination, urgency to urinate and sometimes urge incontinence. In SNS therapy for overactive bladder, the electrical pulses from the neurostimulator target the Global Sacral Nerve Stimulation that control the bladder. They block the abnormal signals from the bladder to the brain that cause the symptoms. This allows the bladder to store more urine and delay the urge to urinate. The therapy can significantly reduce episodes of urgency, frequency and urge incontinence in patients with overactive bladder. During the initial test phase, temporary thin wires are placed near the sacral nerves through the skin to test response. If symptoms improve by at least 50%, a permanent neurostimulator is then implanted.

Benefits for fecal incontinence

Fecal incontinence occurs due to weakened or damaged pelvic floor muscles and nerves that normally help maintain bowel control. SNS therapy for fecal incontinence involves stimulating specific sacral nerves that regulate bowel function. The electrical pulses restore communication between the nerves that control bowel function and sphincter muscles. This enables improved sensation from the rectum and stronger contraction of anal sphincter muscles. As a result, patients realize improved awareness of bowel urgency and ability to delay defecation. It also enhances continent retention of stool in the rectum. In cases where the therapy provides at least 50% reduction in incontinence episodes during the test phase, a permanent neurostimulator may be implanted.

Surgical procedure involved

The surgical procedure for SNS therapy is minimally invasive and typically performed under local anesthesia. It involves making a small skin incision in the lower back or buttocks region near the tailbone. A thin temporary lead wire is then placed near the target sacral nerve through this incision using imaging guidance. The lead is tunneled under the skin and connected to an external pulse generator. The generator is worn outside while nerve stimulation is delivered through the temporary lead over 3-7 days. This test phase allows assessment of symptom improvement. If effective, the patient returns for a second procedure under light sedation or general anesthesia to implant the permanent neurostimulator device.

Candidates who may benefit most

Sacral nerve stimulation therapy is an option for patients whose symptoms of overactive bladder or fecal incontinence are not adequately controlled by lifestyle changes, pelvic floor exercises or medications. It is particularly suitable for those who cannot tolerate or do not get sufficient relief from anticholinergic medications. Patients who respond well to the temporary test phase and show at least a 50% reduction in symptoms are most likely to realize long term benefit from permanent implantation. Good candidates typically present with urinary frequency of 8 times or more per day or weekly episodes of fecal incontinence. They must have no anatomical defects in the bladder, urethra or anorectal region.

Risks and side effects

Being a minimally invasive procedure, risks of nerve stimulation surgery are low but may include pain, infection, bleeding or lead migration. Potential side effects during permanent implantation include pain or numbness in the lower back, buttocks or leg, which are usually mild and temporary. In rare cases, there may be a transient worsening of symptoms which subsides over weeks. Device-related complications are also infrequent but can include lead fracture or generator malfunction requiring replacement surgery. Patients should be aware permanent implants have lifetimes of 5-7 years on average and will eventually need replacement to continue therapy. Overall, complications are uncommon and the therapy is generally very safe when performed by an experienced urologist.

Is it right for you?

Sacral nerve stimulation provides an effective treatment option for many patients with medication-refractory overactive bladder or fecal incontinence. It allows restoration of bladder or bowel control through a minimally invasive approach without the side effects of oral medications. While not a cure, it can significantly improve quality of life by reducing frequency and urgency of urination or episodes of fecal incontinence. Patient satisfaction rates are high. The initial test phase helps identify individual response without undergoing a major implantation surgery. Those experiencing at least a 50% symptom improvement from testing are prime candidates for long term benefits with a implanted system. Consultation with a urologist can help determine if SNS therapy may be suitable.

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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it