Intra-operative Assessment of Cavernosal Nerve Stimulus Threshold

Intra-operative Assessment of Cavernosal Nerve Stimulus Threshold

Erectile dysfunction persists in approximately 80% of men 1 year after prostatectomy. Various erectile rehabilitation strategies have not provided benefit. Electrical stimulation has been demonstrated to benefit neuroregeneration and the functional recovery of neuromuscular systems. Therefore, electrical stimulation of the cavernosal nerves during radical prostatectomy is being investigated for its potential development into a treatment aimed at improving recovery of erectile function after prostatectomy. This pilot study is intended to determine the threshold of electrical stimulation that results in penile erection, as defined by persistent intracavernosal pressure increase, such that future studies of sub-threshold stimulation may be pursued.

Objective:

To determine the cavernosal nerve electrical stimulation amplitude thresholds at which an erection, as indicated by persistent increases in intracavernosal pressure, occurs for various stimuli of fixed frequency and fixed pulse-width.

Study Design:

This is a prospective pilot study used to determine a threshold range of cavernosal nerve electrical stimulation parameters that result in penile erection. Assignment to the order of stimulation paradigms will be randomized. No placebos are used. No blinding is used.

Inclusion Criteria:

• Subjects must have prostate cancer being treated via radical prostatectomy by a single surgeon (primary investigator) with planned intraoperative nerve sparing.
• Subjects must have intact preoperative erectile function, sufficient for penetrative intercourse without medication nor assistive device, as defined by a Sexual Health Inventory for Men (SHIM) / International Index of Erectile Function (IIEF-2) score 22 or higher, which is collected as part of routine care.
• Subjects must have the ability to understand and the willingness to sign a written informed consent document.

Exclusion Criteria:

• Baseline erectile dysfunction, as defined by the use of medications or devices to assist erection, lack of baseline erections, or a SHIM / IIEF-2 21 or lower, which is collected as part of routine care.
• Lack of successful intraoperative nerve sparing.
• Neurologic, metabolic, or vascular diseases that may negatively impact erectile function, such as: diabetes mellitus, peripheral vascular disease, coronary artery disease, stroke, multiple sclerosis, parkinson's disease, multiple systems atrophy, epilepsy, or spinal cord injury.
• Inability to provide a fully informed consent.