SACRAL NERVE STIMULATION (SACRAL NEUROMODULATION)

Sacral nerve stimulation (also known as sacral neuromodulaon) is a therapeutic method used for bladder and bowel diseases. Its use was first reported by Tanagho and Schmidt in 1988 for the treatment of urinary dysfunction. Later on, utilization of sacral  nerve stimulation for bowel dysfunction was appreciated. In this method, stimulation of the sacral nerve causes contraction of sphincters and pelvic floor muscles, which in turn causes changes in the contraction patterns of bladder or bowel.

Sacral neuromodulation involves the implantation of a stimulator subcutaneously for delivering low amplitude electrical stimulation via a lead to the sacral nerve, usually accessed via the S3 or S4 foramen. The  pulse generator is generally placed in a subcutaneous pocket in the upper-outer quadrant of the buttock or the lower abdomen.

For patients who interested in to receive this treatment, a testing is required. During the testing, often referred to as peripheral nerve evaluation (PNE), external electrical stimulation is delivered via a temporary lead inserted percutaneously through the 3rd sacral foramen to the S3 nerve. After a screening period of 2 to 3 weeks, the patient’s response to treatment is assessed. For this assessment, diaries and/or a questionnaires regarding bowel or bladder functions are used. Then, if sufficient clinical improvement is evident, the patient may be considered as eligible for permanent implantation.

Conditions which may be benefited from sacral nerve stimulation includes:

• Urinary urge
• Fecal incontinence
• Idiopathic constipation
• Urinary retention
• Interstitial cystitis
• Treatment of chronic anal fissure