Sacral Nerve Stimulation (SNS)
What is it and what is it for?
SNS is used in patients with faecal incontinence to improve symptoms and in some cases to fully restore continence. Faecal incontinence is initially treated using conservative measures, such as dietary advice, anti-diarrhoeal medication and physical and behavioural therapy. Surgery is indicated when conservative treatments have been unsuccessful.
SNS is an alternative, minimally invasive approach to the treatment of faecal incontinence.
What preparation is needed before?
Before the procedure other investigations such as a flexible sigmoidoscopy (camera test of the latter end of the large bowel), MRI scan may be required in some patients to assess for other pathology.
What does the investigation/procedure entail?
The procedure will be performed in stages. The first procedure may be done under local anaesthetic or general anaesthetic (GA) as a day procedure. The second procedure is also carried out usually as a day case procedure (may require admission to hospital for a day in some cases) and will be performed under GA. You may be asked to attend a pre-op assessment clinic few weeks prior to the surgery where routine health check prior to GA will be carried out.
First procedure (Test phase): Small lead is placed into the muscles of the anus from the lower back with an external pulse generator which stimulates the muscle to contract. The patient is asked to keep a diary of his/her bowel habit. The patient is then sent home and response to the test stimulator is assessed.
Second procedure: If there is a good response to the test stimulator a permanent pulse generator may be implanted. This is a 1-2 hour procedure. Permanent leads inserted and the pulse generator will be inserted underneath the skin over the buttock region and the device will have been activated. Modern devices have a long battery life span and will last for many years.
If the patient wishes for the device to be removed at a later date this will require further surgery.