Abstract:
Objective: To determine the neurovascular anatomy along the penile shaft and in the penile hilum, including glanular innervation for applying to sex reassignment surgery and other penile surgical procedures. Materials and methods: The topography of the deep dorsal veins, and the dorsal arteries and nerves along the penile shaft was investigated in 32 fresh adult cadavers. 11 soft-preserved adult male cadavers were dissected to document the neurovascular structures in the penile hilum. Concerning the innervation of the glans penis, immunohistochemical study was employed to observe and document the distribution of the dorsal nerves and the genital corpuscles in 32 adult male cadavers. The clitoral specimens were obtained from 3 cadavers for comparative study of the distribution of nerves and the genital corpuscles. Results: On the shaft, the dorsal artery was present bilaterally in 22 of 32 cadavers; however, it was present unilaterally in remaining cadavers, predominantly on the left. The mean distance between the left and right dorsal arteries at the neck of the penis was 1.77 cm. The dorsal nerve was identified bilaterally in all cadavers. From the root to the neck of the penis, it fanned out into small branches that divided into two groups. The first group of fibers innervating the glans coursed along the dorsolateral surface of the shaft and pierced the entire area of the corona of the penis posteriorly. The other group diverged to distribute throughout the lateral surface of the shaft to innervate the lateral and ventral portions of the shaft. The mean distance between the left and right medial main branches of the dorsal nerves, which terminated in the glans penis, was 1.18 cm. In the hilum, the penile arterial supply showed several anatomical variations such as the presence of accessory pudendal arteries, multiple cavernous and bulbourethral arteries, and the origin of cavernous and bulbourethral arteries. Immunohistochemical analysis revealed that the main branches of the dorsal nerves after entering the glans divided into terminal branches that concentrated around the urethra. Also, there were differences in the genital corpuscles and the structures within the glans penis and glans clitoris. Conclusion: This detailed anatomy of the neurovascular structures along the penis can provide a valuable guide for applying to sex reassignment surgery, other penile surgical procedures and pelvic surgeries.