Noncontact stimulation of the cavernous nerves in the rat prostate using a tunable-wavelength thulium fiber laser

Background and Purpose: Laser nerve stimulation has recently been studied in neuroscience as an alternative to electrical stimulation. Its advantages include noncontact stimulation, better spatial selectivity, and elimination of electrical stimulation artifacts. This study explored laser stimulation of the rat cavernous nerves as a potential alternative to electrical nerve mapping during nerve-sparing radical prostatectomy. Materials and Methods: The cavernous nerves were surgically exposed in 10 male rats. A thulium fiber laser stimulated the nerves, with a wavelength of 1870 run, pulse energy of 7.5 mJ, radiant exposure of 1 J/cm(2), pulse duration of 2.5 msec, pulse rate of 10 Hz, and 1-mm laser spot diameter, for a stimulation time of 60 sec. Results and Conclusion: A significant increase in the intracavernosal pressure was detected on laser stimulation, with pressure returning to baseline values after stimulation ceased. This study demonstrates the feasibility of noncontact stimulation of the cavernous nerves using near-infrared laser radiation.