The effects of cavernous nerve grafting following surgically induced loss of erectile function in a large-animal model.
BACKGROUND
Prostate cancer is the second most common cause of cancer deaths in men in the United States. Many patients experience partial or complete loss of erectile function following prostatectomy. The cavernous nerves can be reconstructed intraoperatively using sural nerve grafts in an attempt to restore erectile function.


METHODS
In this study, multiple anatomical dissections and neurologic assessments were used to define the position and histologic parameters of the cavernous nerve in a canine model. The subsequent experimental design included three groups of adult mongrel dogs followed for an 8-month period. Group 1, the control group, underwent bilateral nerve ablation to substantiate surgically induced loss of erectile function. Group 2, the "sham" group, underwent exploration only. Group 3 underwent bilateral cavernous nerve ablation with bilateral sural nerve graft reconstruction. Erectile function was evaluated with indirect electrical nerve and manual penile stimulation preoperatively and 1, 2, 4, 6, and 8 months postoperatively. Direct nerve stimulation and histologic analysis was preformed at the first operation and at the time the animals were euthanized at 8 months.


RESULTS
Bilateral cavernous nerve ablation resulted in a significant loss of erectile function for 8 months postoperatively in the control animals. The sham animals demonstrated preservation of erectile function immediately following exploration. The animals in the grafted group demonstrated a significant return of erectile function by 4 months compared with preoperative measurements and by 2 months compared with control animals.


CONCLUSIONS
This study establishes the first large-animal model for surgically induced loss of erectile function with successful cavernous nerve graft reconstruction, and it provides the unique opportunity to explore the effects of changes to this model in the future.
Lowe
James B
JB
Division of Plastic and Reconstructive Surgery, Washington University School of Medicine, USA. drjimlowe@sbcglobal.net
Hunter
Daniel A
DA
Talcott
Michael R
MR
Mackinnon
Susan E
SE
D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D007172:Erectile Dysfunction / Q000601:surgery*; D007001:Hypogastric Plexus / Q000033:anatomy & histology; D008297:Male; D010388:Pelvis / Q000294:innervation; D011467:Prostate / Q000294:innervation*; D013497:Sural Nerve / Q000637:transplantation*; D014182:Transplantation, Autologous