Robotic Intercostal Nerve Graft for Reversal of Thoracic Sympathectomy

Video Assisted Thoracic Sympathectomy for hyperhydrosis sometimes results in debilitating compensatory sweating. We propose a novel minimally invasive treatment to reverse sympathectomy by implantation of an intercostal nerve graft using the da Vinci robot.

Severe compensatory sweating is essentially the most significant limitation to sympathectomy as a treatment option for hyperhidrosis. Modification of surgical technique and better patient selection has each reduced the incidence of severe compensatory sweat. There is still a minority of patients who are dissatisfied and would be candidates for minimally invasive reversal procedure.
We propose a novel treatment option to reverse severe CS secondary to thoracoscopic sympathectomy. We established an animal model in an attempt to test the feasibility of a thoracoscopic reversal of the surgical sympathetic block by using a nerve graft and robotic microsurgery.

The thoracic sympathetic chain was identified along the heads of the ribs in the upper thorax. The parietal pleuron was dissected with ultrasonic shears (Ethicon, Cincinnati, OH) at about the T4 vertebra. A segment of the sympathetic chain was dissected free of parietal pleura using a combination of blunt and sharp dissection. At first, a posterior tibial nerve graft was used, which was harvested from the animals right lower hind leg. The size mismatch was significant, and it was decided to use an intercostal nerve graft. Therefore, a 2 cm long segment of inter-costal nerve in the adjacent lower rib border was identified and dissected similarly in the neurovascular bundle. The edges of the nerve were cut using robotic micro scissors to create clean, smooth surfaces. After harvesting the nerve from the nerve space, this cut segment was brought in proximity to the freed portion of the sympathetic chain. It was noted that the sizes of the two nerves were almost equal. The freed sympathetic chain was then divided at approximately T4 level using robotic micro-scissors. The nerve graft segment was aligned in the plane of the sympathetic chain. Using robotic micro-forceps, a 10-0 Nylon suture was used to suture the proximal end of nerve graft to the proximal cut end of sympathetic chain. Four interrupted sutures were used in total to join the two cut ends. The distal ends were sutured in a similar fashion. Partial closure of the divided parietal pleura over the grafted nerve was performed to prevent dislodgement of the graft by the movements of the lung on expansion.