Percutaneous Nerve Evaluation Trial Time

Sacral neuromodulation (SNM) is a minimally invasive procedure that provides low-amplitude electrical stimulation to the S3 nerve root to improve micturition and defecation. Patients who elect to proceed with SNM undergo a trial phase to determine therapeutic response prior to placement of a permanent implantable pulse generator (IPG). A trial phase can be performed in two ways: a percutaneous nerve evaluation (PNE) or staged implantation. PNE involves the placement of a temporary wire connected to an electrode using external stimulation. It is performed in the office using local anesthesia. If the patient displays adequate improvement in symptoms (defined as \>50% improvement of symptoms from baseline), a permanent lead and subcutaneous IPG are implanted in the operating room.