Although, the presence and frequency of APAs have been studied, and the ability to preserve them has also been noted, we still do not know how much these arteries contribute to a male's erection. With this study, we plan to evaluate whether APAs supply blood to the penis and male erections, as well as the amount supplied. While there is no immediate benefit to you for participating in the study, these findings will further help our understanding of APA's and the importance in preserving them during surgery.