RESUMO
Ramicotomy is a surgical procedure, with less adverse effects than conventional sympathectomy, however, it was abandoned due to the high recurrence rate. Twenty-eight pigs underwent bilateral videothoracoscopic ramicotomy and were divided into five groups. The animals were sacrificed at 15th, 45th, 90th, 135th and 180th postoperative days (POD). The segments were removed and evaluated for macroscopic regeneration and histological analysis. The data were compared to the control group of 10 intact segments of the sympathetic. There was no macroscopic regeneration on the 15th POD, and present on 41.6% on the 180th POD (P<0.05). The Schwann cells presented a similar evolution in both rami beginning at the 45th POD, with a smaller count in the gray rami. The collagen and reticular fibers presented a negative correlation (r=-0.414; P<0.01). The deposition of the collagen fibers was greater in the gray rami with a peak deposition on the 135th POD and a diminishing rate in the 180th POD (P<0.05). Ramicotomy allows complete section of all rami communicantes of the sympathetic ganglia. The histological regeneration might be greater than the recurrence rates of clinical symptoms seen in a human being due to non-functional regenerations.