Erogenous Sensate Vaginal Flap for Male to Female Vaginoplasty

Purpose: The lack of erogenous sensitivity in the neo-vagina is one of the major shortcomings for patients undergoing male to female genital confirmation surgery. A clitoral flap derived from the glans penis serves as the only source of erogenous sensitivity for these patients.  A cadaveric and histological based comparison of the branches of the dorsal nerve of the penis (DNP) utilized in and remnant after the harvest of the clitoral flap is done to assess the feasibility, optimal design, and potential benefits of a sensate neurovascular pedicle flap for erogenous vaginal sensation in this patient population.

Methods: An anatomic dissection of the DNP was performed in 10 male pelvises to identify major trunks and their branches. Their location, diameter, branching pattern along the dorsal aspect of the penis were recorded. Main branches of DNP within the medial dorsal aspect of the penis were preserved for a clitoral flap, while those more lateral were used as innervation for the sensate vaginal flap. The number of main branches in the lateral dorsal aspect of the penis were calculated to ensure sufficient erogenous innervation to vaginal flap. Cross-sections of the penis at proximal and distal points were used for histological analysis with similar medial and lateral compartmentalization. An optimal width and length of the sensate vaginal flap was recommended based on these cadaveric findings.  

Results: The DNP was composed of on average 4, 5, 6 main branches in 2 (20%), 4 (40%), and 4 (40%), cadavers respectively. Lateral main branches with 1, 2, and 3 main branches in the lateral compartment seen in 2 (20%), 6 (30.7%), 2 (42.8%) cadavers, respectively. These findings were consistent with histological cross-sectional analysis, and further showed increasing branching with more distal cross-sections. A sensate vaginal flap from the lateral aspect of the glans penis with a mean width of 1.14 cm (range, 0.9 – 1.28 cm) ensured at least one main branch of the DNP for erogenous sensitivity. This sensate vaginal flap and its neurovascular pedicle had mean length of 9.8 cm (range, 8.7 to 10.3) allowing its rotation into the anterior vaginal canal.   

Conclusion: Lateral branches of the DNP can be preserved after clitoroplasty for reconstruction of a sensate vaginal flap that measures approximately 1 cm in width and has neurovascular pedicle between 8.7 to 10 cm in length. Inset within the anterior vagina wall, this sensate flap can provide patients with an erogenous vaginal “spot” during male to female confirmation surgery. Future clinical studies are required to assess the erogenous function of the flap and impact on patient sexual function and quality of life.