Initial evaluation of robotic technology for microsurgical vasovasostomy

Conventional microscope assisted vasovasostomy (MAVV) is a technically difficult procedure that is most successful in the hands of well-trained microsurgeons. Robotics may help surgeons overcome the microsurgical challenges of tremor, limited dexterity, miniaturized instrumentation and use of fine suture. We determine the feasibility of a robotic assisted vasovasostomy (RAVV) and compare performance measures with those of conventional MAVV.

One surgeon performed 10 vasovasostomies with a modified 1-layer technique and 9-zero suture on fresh human vas specimens using the robot in 5 RAVV cases and standard microsurgical instrumentation in 5 MAVV cases. Pre-specified performance measures and adverse haptic events (broken sutures, bent needles or loose stitches) were recorded. Patency was evaluated by instilling saline through the anastomoses.

Mean operating time and number of adverse haptic events were higher for RAVV than for MAVV (84 vs 38 minutes, p = 0.01; 2.4 vs 0.0 events, p = 0.03). The number of needle passes required for the 6 full-thickness stitches was similar in both groups (16.8 vs 15.2 passes, p = 0.55). Although no tremor occurred during RAVV, minimal to moderate amounts occurred during MAVV. Minimal fatigue was noted for both groups. Patency was confirmed in all 10 operations.

Use of RAVV in this human ex vivo vas model was feasible. While RAVV took longer to perform and was associated with adverse haptic events, elimination of tremor and comparable patency rates suggest that it may be a viable surgical alternative for microsurgical vasovasostomy.