Robot-assisted microsurgical vasovasostomy: the learning curve for a pure microsurgeon.

Vasovasostomy success rates improved with the application of the operative microscope in 1975. The robotic platform offers potential advantages including: a stable, ergonomic, scalable control system with three-dimensional visualization and magnification, the elimination of physiological tremor, and simultaneous control of three instruments and a camera. A previous publication revealed a fellowship-trained microsurgeon (PKK) could transition to robot-assisted microsurgical vasovasostomy (RAVV) with comparable outcomes. The objective of this current study was to evaluate the learning curve for the purely trained microsurgeon transitioning to RAVV. A retrospective chart review was performed of a microsurgeon's first 100 RAVVs evaluating the learning curve for patency rates, anastomosis times, operative times, and sperm concentrations at the initial postoperative semen analyses. Cases were stratified into four groups by 25 case intervals. There were no statistically significant differences in patency rates or postoperative sperm concentrations between the groups over time. There were differences in anastomosis times between groups 1 and 2, as well as between groups 2 and 3, and there were differences in operative times between groups 2 and 3. High-percentage patency rates are achievable very early in the transition from pure microsurgical vasovasostomy to RAVV across wide ranges of obstructive intervals. Postoperative mean sperm concentrations in the initial semen analyses after RAVV are consistent over time. For a single microsurgeon not formally trained in robotic microsurgery, 75 RAVV cases were required to optimize and plateau in anastomosis times and 75 cases were required to optimize operative times.