title: Temperature-controlled optical stimulation of the rat prostate cavernous nerves.
abstract: Optical nerve stimulation (ONS) may be useful as a diagnostic tool for intraoperative identification and preservation of the prostate cavernous nerves (CN), responsible for erectile function, during prostate cancer surgery. Successful ONS requires elevating the nerve temperature to within a narrow range (~42 to 47°C) for nerve activation without thermal damage to the nerve. This preliminary study explores a prototype temperature-controlled optical nerve stimulation (TC-ONS) system for maintaining a constant (±1°C) nerve temperature during short-term ONS of the rat prostate CNs. A 150-mW, 1455-nm diode laser was operated in continuous-wave mode, with and without temperature control, during stimulation of the rat CNs for 15 to 30 s through a fiber optic probe with a 1-mm-diameter spot. A microcontroller opened and closed an in-line mechanical shutter in response to an infrared sensor, with a predetermined temperature set point. With TC-ONS, higher laser power settings were used to rapidly and safely elevate the CNs to a temperature necessary for a fast intracavernous pressure response, while also preventing excessive temperatures that would otherwise cause thermal damage to the nerve. With further development, TC-ONS may provide a rapid, stable, and safe method for intraoperative identification and preservation of the prostate CNs.
authors.affiliation: University of North Carolina at Charlotte, Department of Physics and Optical Science, Charlotte, North Carolina 28223-0001, USA.
authors.forename: Serhat
authors.initials: S
authors.lastname: Tozburun
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Hutchens
authors.forename: Michael A
authors.initials: MA
authors.lastname: McClain
authors.forename: Gwen A
authors.initials: GA
authors.lastname: Lagoda
authors.forename: Arthur L
authors.initials: AL
authors.lastname: Burnett
authors.forename: Nathaniel M
authors.initials: NM
authors.lastname: Fried
mesh_terms: D000818:Animals; D002138:Calibration; D003198:Computer Simulation; D004867:Equipment Design; D007259:Infrared Rays; D007834:Lasers; D008297:Male; D009900:Optic Nerve / Q000502:physiology*; D010410:Penile Erection; D010413:Penis / Q000294:innervation*; D011467:Prostate / Q000294:innervation / Q000601:surgery; D011471:Prostatic Neoplasms / Q000601:surgery; D011874:Radiometry / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D013696:Temperature