Anatomical variation of sympathetic ganglia in R4+R5 sympathicotomy for primary palmar axillary hyperhidrosis.

Background: R4+R5 sympathicotomy is one of the standard surgical treatments for primary palmar axillary hyperhidrosis (PAH), but the reported outcomes vary. Anatomical variation of sympathetic ganglia is hypothesized to be a cause for this phenomenon. The sympathetic ganglia could be visualized via near-infrared (NIR) fluorescent thoracoscopy, we utilize this novel technique to observe the anatomical variation of sympathetic ganglia T3 and T4 and investigate its relationship with surgical outcomes. Methods: This is a prospective multi-center cohort study. All patients received intravenous indocyanine green (ICG) infusion 24 hours preoperatively. Anatomical variation of sympathetic ganglia T3 and T4 was observed via fluorescent thoracoscopy. Standard R4+R5 sympathicotomy was performed regardless of anatomical variation. Patients were followed up for the therapeutic outcome. Results: One hundred and sixty-two patients in total were enrolled in this study and 134 patients with bilateral clearly visualized thoracic sympathetic ganglia (TSG) were included. The success rate of fluorescent imaging of thoracic sympathetic ganglion was 82.7%. The T3 ganglion was shifted downward on 32 sides (11.9%) and no upward-shifted ganglion was identified. The T4 ganglion was shifted downward on 52 sides (19.4%) and no upward-shifted ganglion was identified. All patients underwent R4+R5 sympathicotomy and no perioperative death or severe complication occurred. The total improvement rates on palmar sweating at short-term and long-term follow-up were 98.1% and 95.1%, respectively. There were significant differences between T3 normal and T3 variation subgroups both in short-term (P=0.049) and long-term (P=0.032) follow-ups. The total improvement rates on axillary sweating at short-term and long-term follow-ups were 97.0% and 89.6%, respectively. No significant difference was found between T4 normal and T4 variation subgroups both in short-term and long-term follow-ups. No significant difference was found between normal and variation subgroups on the degree of compensatory hyperhidrosis (CH). Conclusions: NIR fluorescent thoracoscopy provides clear identification of anatomical variations of sympathetic ganglia during R4+R5 sympathicotomy. The improvement of palmar sweating was significantly affected by anatomical variation of T3 sympathetic ganglia.