Call us directly: +44 (0) 30 0302 0202

Emmanuel Kaye House View Location

Sacral Nerve Neuromodulation

In order to understand how Sacral Nerve Neurmodulation can help overcome bladder dysfunction we need to understand how a “normal “ Urinary system works:

The Urinary system consists of two kidneys one each side situated just below the rib cage. Their main function is to regulate the amount of fluid in the body and flush out toxins. The kidneys are connected to the bladder via long tubes known as ureters, there is one for each kidney. The bladder sits in the pelvis. The bladder has elastic properties allowing to both store and void urine. As urine is passed into the bladder from the kidneys it increases in size, on voiding the bladder contracts to empty via another tube known as the urethra, much like a balloon would behave if you filled it with water then emptied it. To stop urine leaking out of the bladder until it is convenient to empty the urethral sphincter is normally contracted to prevent flow of urine. It is only when this muscle is relaxed that urine can flow, think of the sphincter as a tap.

To function correctly the bladder sends and receives signals to the brain through nerves known as sacral nerves. These nerves send and receive commands between the brain, bladder and urethral sphincter. As the bladder fills signals are sent along the nerves to the brain, as the bladder becomes fuller the signals become stronger. The emptying of the bladder should be a purely voluntary control, so you decide when it is convenient for the return signal from the brain to be sent to the bladder. This signal will cause the sphincter muscle to relax (tap turned on) and the bladder muscle to contract, resulting in successful emptying of the bladder

If you are one of the six million people in the UK who suffer bladder dysfunction these signals may be disrupted. If the signals to the bladder are affected this will cause over activity of the bladder, or if they affect the sphincter muscle it can cause urinary retention.

Bladder dysfunction affects people of any age and can have a devastating effect on the quality of life, curtailing everyday activities and making social lives very difficult or even impossible for fear of leakage and a need to be near a bathroom at all times.

To help alleviate these problems a procedure known as Sacral Nerve Neuromodulation may be performed.

Sacral Nerve Neuromodulation involves modulation of the sacral nerves using electric current. This is achieved by sending a tiny, pulsed electrical current to the sacral nerves from a ‘bladder pacemaker’ device. Pulse width modulation is a way of rapidly pulsing the digital signal being sent down a wire to simulate varying voltages on the wire. If you think of the dimmer switch in your home or the varying speeds of the washing machine that is pulse width modulation. This is very similar to how the bladder and brain work together i.e. as the bladder fills the frequency of the pulse to the brain increases. Rapid strong pulses tell the brain the bladder is reaching maximum capacity and voiding needs to take place. The brain can then respond by reducing the frequency of the pulses being sent down the sacral nerve to the sphincter muscle causing the muscle to relax at the same time the frequency of the pulses being sent to the bladder muscle increase making the muscles contract. You may remember from science lessons at school how you could get the muscles in frog legs to relax and contract by applying a small voltage from a battery.

In people with bladder dysfunction the electrical pulses sent between the bladder and brain become disrupted. This leads to the signals being sent to the bladder to occur to early causing contractions to occur before the bladder is full and the patient ready. This results in the symptoms of frequency, urgency and leakage (incontinence) that are known as an overactive bladder.

In the case of Urinary retention the signal from the brain keeps the sphincter muscle contracted and unable to relax.

Sacral Nerve Neuromodulation sends a tiny pulsed electrical current in the same way as the human body does to the sacral nerves. So that communication between the brain, bladder and associated muscles is once again correct enabling near normal function to be resumed.

Can Sacral Nerve Neuromodulation help me?


If you suffer from any of the following bladder dysfunctions then Sacral Nerve Neuromodulation may be a suitable option

Overactive Bladderwhere the muscles contract at the wrong time resulting in incontinence and urgency

Frequency and urgency – uncontrollable urges to pass water and voiding often in very small amounts

Urinary retention -The inability to empty the bladder.

Pelvic pain syndrome and interstitial cystitis


Pelvic pain can be a very deliberating condition the cause of which are not yet that well understood. Interstitial cystitis is an inflammation of the bladder making it very sensitive as the bladder fills, this in turn causes chronic pain, frequency and urgency to pass water.


Sacral Nerve Neuromodulation will not help in cases where

Urinary Retention is due to a physical obstruction to the flow of urine i.e. an enlarged prostate or a narrowing of the urethra.

Where Urinary incontinence due to weak pelvic floor muscles (stress incontinence)

What Happens next

Test Implant   

images-3To see is whether Sacral Nerve Neuromodulation will be effective for you you’re Urologist will ask you to come in for a small test procedure. Under local anesthetic a very thin wire will be inserted to make contact with the sacral nerve. The wire is then connected to a simulator control box (pulse width modulator) where the strength and frequency of the electrical signals being generated and sent down the wire to the sacral nerves, this can be adjusted to achieve the desired result.

You are then able to go home with an external test control unit, this can be attached to a belt, for a few weeks and asked to monitor your bladder behavior during this time the device can be fine tuned to your specific requirements. If the trail period is successful, then a permanent implant can be carried out




Permanent Implant

Once it has been established show that stimulation successfully alters bladder function and you are happy to proceed. You will be asked to come back into hospital to have the Interstim II sacral images-4nerve implant. Under a general anesthetic. A small incision will be made in the buttock area the Interstim II sacral nerve simulator will be implanted, a permanent electrode will also be inserted to connect the device to the sacral nerves in your lower back. After the operation, you will be shown how the device works. You will normally be able to go home the same day with a follow up appointment being made to see you in clinic to check that the device is working well and that your symptoms have improved

Interstim II sacral nerve implant

As you can see the device is very small about the size of a Two Pound Coin










Why haven’t I heard of this treatment?

Sacral neuromodulation was first described in 1998 and now has 10 years of accumulated evidence establishing its effectiveness and safety. It was approved by NICE (National Institute for Health and Clinical Excellence) in 2003 and is widely used in Spain, Holland and Germany. However, the technique has not been widely available in the NHS due to cost and limited expertise available in the UK.


How effective is it?

Sacral nerve neuromodulation has proven to be a very safe, effective and long lasting the battery life of the device is 5 to 7 years before needing to be replaced

Research has shown that over 70% of the patients who underwent implantation of the sacral nerve neuromodulator device for urge/frequency and urge incontinence went on to became dry or showed great improvement in symptoms.


Benefits and Risks –


Test period carried out to ensure suitability before full implant

Minimally invasive surgery implant device can be switched off or easily removed at any time

High Success Rate

Improved Quality of Life


As with any surgery there are always some risks these include



Device Failure



Jeremy Ockrim together with the clinics  Specialist Nurse Practitioner  have the largest experience of sacral nerve stimulation for bladder dysfunction in the UK. Jeremy Ockrim is the lead specialist for SNS and bladder dysfunction at University College Hospital, London. Together they have treated over 140 patients in the last 12 months and have many more waiting; with the majority finding their urgency and incontinence has significantly improved or ceased, and over 70% proceeding to the permanent implant after a test stimulation


JeremyOckrim“Sacral neuromodulation is a very important new breakthrough in the treatment of the overactive bladder. It provides an effective solution for women when conservative treatment has not worked. It avoids the risk of catheters with major surgery.”

Jeremy Ockrim, Consultant Urologist, University College Hospital and Harley Street, London





“We have been amazed at our patients’ responses to the new technique. The implant has revolutionised their lives and allowed them to return to social activities, where they had previously lost confidence. We offer continued after care to adjust the device settings according to our patients’ individual needs.”


 Specialist Nurse Practitioner




Getting help

If you wish to make an appointment to seek further advice and or treatment, please contact Mr Ockrim’s secretary.


The information contained within this website has been provided as a general guide and should not be treated as a substitute for the medical advice of your own GP or any other health professional.