Horner's syndrome caused by intra-oral trauma.

A 7-year-old boy developed a Horner's syndrome after falling on a stick that penetrated his peritonsillar soft palate. He did not suffer from any major vascular injury, and pharmacologic testing indicated a preganglionic lesion. We review previously reported cases of oculosympathetic paresis caused by surgical and nonsurgical intra-oral trauma. Because of the proximity between sympathetic and vascular structures in the lateral and parapharyngeal space, Horner's syndrome in the setting of intra-oral trauma should prompt evaluation of the internal carotid artery. Magnetic resonance imaging may be a reasonable noninvasive method for this investigation.