Introduction: Penile microvascular dysfunction is an important contributor to erectile dysfunction (ED) severity. Recently, Laser Speckle Contrast Imaging (LSCI) has been shown to be a useful tool to evaluate penile microvascular perfusion (MVP) changes in humans. While increased penile fibrosis has been shown to impair MVP, transpelvic magnetic stimulation (TPMS) is known to improve MVP. The objective of our study is to: (A) evaluate the time-course of penile microcirculation (using via LSCI) in a rat model of CN crush injury (CNI; animal model of nerve sparing prostatectomy- related ED). (B) determine effect of TPMS on penile MVP after CNI.
Methods: Adult male rats (n=4-5) were anesthetized, and bilateral CN crush was performed under an operating microscope. Through a lower abdominal midline incision, the area posterolateral to the prostate was explored and the major pelvic ganglion (MPG) and CNs were identified and exposed (Fig A-B). In the sham operation group, there was no further surgical manipulation. In the remaining groups, the CNs (distal to the MPG) were crushed for 80s twice using a micro-surgical hemostat. After recovery, animals were monitored for hemodynamic changes. Using a Magventure stimulator with a rat coil, the pelvic region was placed at the center of the coil and rats were further subjected to TPMS [15%) with simultaneous monitoring of penile hemodynamics using LSCI [PeriCam PSI system]. This technique quantifies MVP in arbitrary perfusion units (AU) and displays a real-time perfusion image.
Results: TPMS produced a stimulus dependent increases in MVP and maximal perfusion was observed at 15% amplitude. CNI resulted in ~60% decrease in MVP in the CNI group compared to uninjured controls, at 15% amplitude (Fig C-D ).
Conclusions: Microvascular dysfunction may contribute to increased ED severity after CNI. TPMS is a novel and non-invasive intervention to improve penile MVP after CNI. Potential application includes treatment of ED and sexual function preservation following cancer treatment, possibly through improved penile hemodynamics that were beneficial to possibly prevent penile hypoxia and fibrosis. Future studies are warranted to confirm its utility in human subjects, specifically in prostate cancer survivors. Source of
