Iatrogenic Horner's syndrome.

PURPOSE To report two cases of Horner's syndrome. One presented after the ablation of a schwannoma of the cervical sympathetic chain, the second after upper thorascopic sympathectomy for primary palmar hyperhidrosis. METHODS A 42-year-old man underwent excision of a left neck mass found during routine physical examination. A 20-year-old girl with axillary and palmar hyperhidrosis was treated with cervical sympathectomy. RESULTS In the early postoperative days, miosis, ptosis, anhidrosis, and enophthalmos were observed. CONCLUSIONS In the ablation of a schwannoma, postoperative Horner's syndrome is associated with the relationship between nerves and the tumor mass, which makes it impossible to separate them surgically in most cases. In thorascopic sympathectomy, patients should be warned of this complication.