Thermographic study of palmar and facial skin temperature of hyperhidrosis patients before and after thoracic sympathectomy

The purpose of this study was to investigate the roles of the second thoracic sympathetic segment in the sympathetic innervation of the hands and face, and to compare skin temperature changes in the palms, fingers, face, and neck of palmar hyperhidrosis (PH) patients before and after endoscopic thoracic sympathectomy.Twenty-two patients, 14 women and eight men, with severe PH were treated with endoscopic ablation of the T2 segment. The skin temperatures of the hands, neck, and face were assessed by infrared thermography both before and after operation.All obtained satisfactory relief of PH. Before sympathectomy, thermography revealed that the palmar skin temperature (PST) was significantly lower than the facial temperature by 1.3 degrees C (paired t-test, p0.005). After sympathectomy, thermography showed significant elevations in temperature mainly of the thenars, palms, digits, and nose, but not of the forehead, mandible, or neck (ANOVA, p0.05 with Bonferroni t-test). The variations in PST among PH patients were much greater preoperatively than postoperatively. More prominent postoperative PST elevation was found in PH patients with lower preoperative PST (r = 0.898, p0.001).These findings demonstrate that the T2 segment is the key source of sympathetic innervation to the hand and that the T2 segment contributes only trivial sympathetic innervation to the face. The results of the present thermography studies offer descriptive information about the autonomic innervation of the upper thoracic sympathetic trunk.