Selective MR imaging approach for evaluation of patients with Horner's syndrome.

PURPOSE To assess the usefulness of MR in the evaluation of patients with Horner's syndrome. PATIENTS AND METHODS We prospectively performed MR imaging in 33 patients with Horner's syndrome (13 preganglionic and 20 postganglionic) using a protocol specifically designed for pre- and postganglionic varieties of this syndrome. Assignment of patients to pre- or postganglionic categories was performed on the basis of pharmacologic testing. RESULTS Abnormalities in one-half of the patients with preganglionic Horner's syndrome included lateral medullary infarct, spinal cord/root disease, apical lung tumor, and paravertebral metastatic mass. Three of 20 patients with postganglionic Horner's syndrome had carotid artery dissection. CONCLUSION Routine scanning of patients who have postganglionic Horner's syndrome with cluster headaches was not helpful in our small series.