Percutaneous Tibial Nerve Stimulation (PTNS)

Percutaneous tibial nerve stimulation (PTNS) is one of the least invasive forms of neurostimulation, currently used for a variety of urologic conditions including interstitial cystitis, urge incontinence and overactive bladder (OAB).

Procedure
The treatment is simple. A fine needle is inserted into the skin just above the ankles (at the SP6 acupuncture point) to access the post tibial nerve. A small electrode is then placed on the needle from the TENS unit. A mild electrical current is passed through into the nervous system. If the big toe bends downwards with stimulation, the needle's placement is ideal. Patients may also notice a stretching outward of their outer toes. PTNS stimulation should never cause pain. If the stimulation is too strong, nerve damage may occur. The protocol requires once-a-week treatments for ten weeks, roughly 30 minutes per session.

Research and development
The methodology was first invented by Dr. Marshall Stoller at UCSF Medical Center, San Francisco, and was first known as the SANS protocol. Dr. Stoller's goal was to create an alternative to the more invasive sacral neuromodulation devices. Thus, rather than requiring an incision and placement of electrodes in the sacrum, PTNS utilizes the nerve root (S3) but at a location much closer to the surface of the skin, slightly above the ankle.

In 2000, Dr. Stoller reported that 100 patients were treated with the SANS device with an approximate 80% success rate in treating urge incontinence syndrome, including urgency and frequency. In a corroborative study, 71% of patients achieved success.

The SANS/PTNS protocol has faced challenges in the industrial sector. The first company to attempt to market Dr. Stoller's device was called Urosurge, based in the USA. After conducting an international product launch in London, the company went out of business. Both UCSF & Dr. Stoller then attempted to find another company to carry on their work, to no avail. Another company, Cystomedix, developed a similar device. In Dec. 2004, Uroplasty acquired Cystomedix. Uroplasty currently offers the only PTNS device available today, which they call Urgent PC.

Potential
When compared to the extremely high cost of sacral neuromodulation devices, PTNS represents a far more affordable and less invasive alternative for patients who are considering a nerve stimulation device. Prices differ dramatically in various countries. In the UK, the cost is approximately £600. In the USA, the cost was a few thousand dollars. This protocol is slowly gaining exposure in various urologic clinics but faces stiff competition from the older and more established SNS devices, such as Medtronic's Interstim.