Abstract
Optical nerve stimulation (ONS) has been commonly performed in the laboratory using high-power, pulsed, infrared
(IR) lasers including Holmium:YAG, diode, and Thulium fiber lasers. However, the relatively high cost of these
lasers in comparison with conventional electrical nerve stimulation (ENS) equipment may represent a significant
barrier to widespread adoption of ONS. Optical stimulation of the prostate cavernous nerves (CN’s) has recently
been reported using lower cost, continuous-wave (CW), all-fiber-based diode lasers. This preliminary study
describes further miniaturization and cost reduction of the ONS system in the form of a compact, lightweight,
cordless, and inexpensive IR laser. A 140-mW, 1560-nm diode laser was integrated with a green aiming beam and
delivery optics into a compact ONS system. Surface and subsurface ONS was performed in a total of 5 rats, in vivo,
with measurement of an intracavernous pressure (ICP) response during CW laser irradiation for 30 s with a spot
diameter of 0.7 mm. Short-term, CW ONS of the prostate CN’s is feasible using a compact, inexpensive, batterypowered
IR laser diode system. This ONS system may represent an alternative to ENS for laboratory studies, and
with further development, a handheld option for ONS in the clinic to identify and preserve the CN’s during prostate
cancer surgery.
