Peripheral Nerve Evaluation (PNE)

Fecal incontinence can be embarrassing, and many people do not feel comfortable bringing up this condition with their doctor. If you are experiencing leakage of feces, you are not alone. More than half of older adults suffer from some type of leakage, but young people can experience incontinence as well.

Some common causes for incontinence may include:

  • Chronic diarrhea or constipation.
  • A disease or injury that damages the nervous system.
  • Poor overall health from a long-lasting illness.
  • Difficult childbirth that damages the pelvic floor and tissues that support the rectum.
  • Poor control or deterioration of the sphincter muscles.

Incontinence can manifest itself in varying degrees, from minimal difficulty controlling gas to episodes of seepage or soilage, or as significant as the inability to control solid stool. The good news is that incontinence is a condition that can be improved with proper treatment.

InterStim Therapy
For some patients, fecal incontinence can be managed with medication, dietary changes and behavior modification. In some cases, however, these changes are not enough. Sacral Neuromodulation delivered by InterStim Therapy treats pelvic floor dysfunction and has proven to be effective for fecal incontinence. InterStim Therapy is:

  • Safe
  • 100 percent reversible
  • Unique in its ability to offer patients a trial period to evaluate the therapy

How it works:
Pelvic floor dysfunction includes two components - muscle and nerve. InterStim therapy is FDA-approved and targets the sensory or nerve side of the bowel. The problem might be a miscommunication between your brain and the nerves that innervate your bowel. Gentle stimulation of the sacral nerve can reduce the signals to the central nervous system, which is causing the overactivity. This often improves symptoms. InterStim therapy will not cure all bowel problems, but it may help you to resume your daily activities.


Basic Evaluation:
The diagnostic evaluation, peripheral nerve evaluation (PNE), is an outpatient procedure with no incision. The average evaluation lasts about 15 minutes. Your physician will begin by numbing your skin with local anesthetic and then placing two thin simulation electrodes under the skin near the tail bone. The nerves that control bowel function are found below this area.

The two thin wires will be attached to an external test stimulator that can be worn on a belt, which you will wear for approximately one week. The device will provide mild pulses of energy to the nerves that control the pelvic floor as you return to your normal activities. The treatment can be stopped, started and adjusted using a controller. It is very simple to use, and your doctor will show you the features of the controller during your appointment. Over the course of the test period, if you show an improvement in symptoms of 50 percent or greater, you may be a candidate for long-term treatment with InterStim therapy.


Tracking Your Progress
During the basic evaluation, you will record information about your bowel episodes on a symptom tracker including:

  • Frequency of bowel episodes
  • Amount of incontinence experienced
  • Urgency

You will bring your symptom tracker to your doctor's appointment to help make an informed decision about the long-term value of sacral nerve stimulation and whether InterStim therapy is the best treatment option for you.


Potential Complications
Your doctor or nurse will provide you with information about operating the device and inform you about precautions and activity restrictions. You should be able to do all your normal activities throughout the evaluation period, except for bending, lifting or twisting movements. Complications during the evaluation are rare but include:

  • Movement of the wire
  • Technical problems with the device
  • Temporary pain
  • Interactions with diagnostic equipment such as MRI
  • Undesirable changes in bowel function
  • Uncomfortable jolting or shocking feeling during nerve stimulation

Most issues can be resolved easily with a call to your doctor.