Horner's syndrome caused by a thoracic dumbbell-shaped schwannoma: sympathetic chain reconstruction after a one-stage removal of the tumor.

Abstract

A case of Horner's syndrome caused by a thoracic dumbbell-shaped schwannoma is reported. To report a rare case of a mediastinal dumbbell-shaped schwannoma as a cause of Horner's syndrome and to show the result of intercostal nerve grafting for sympathetic chain reconstruction after resection of the sympathetic nerve. It has been reported that approximately 10% of neurogenic mediastinal tumors extend through the neural foramen into the spinal canal, creating a dumbbell shape. Although the most frequent causes of Horner's syndrome are tumors, a dumbbell-shaped schwannoma has rarely been described as a cause of the syndrome. Moreover, there have been no previous reports that primary sympathetic chain reconstruction has been performed with an intercostal nerve graft after resection of the sympathetic nerve with the tumor. A 48-year-old woman was diagnosed with a mediastinal tumor by routine chest radiography. The patient had right-sided Horner's syndrome, the signs of which she had not noticed. Surgical resection of the dumbbell-shaped tumor was performed in a one-stage combined resection of both the intraspinal and the mediastinal component of the tumor. Primary sympathetic chain reconstruction was also performed with an intercostal nerve graft. The tumor was resected completely, and no recurrence of the tumor was observed 1 year after the operation. Blepharoptosis and anhidrosis on the right side of her face and upper limb gradually improved after surgery, and compensatory oversweating on the left side eventually improved. In bright illumination, the right pupil diameter was 3.5 mm and the left was 5 mm after surgery; the right pupil measured 4 mm and the left measured 5 mm 1 year after the operation. A mediastinal dumbbell-shaped schwannoma has rarely been described as a cause of Horner's syndrome. Primary sympathetic nerve reconstruction with an intercostal nerve was shown to be useful after resection of the sympathetic nerve involved in the tumor.