Facial spasm and vertical nystagmus in a patient with Chiari type I malformation.

Abstract

Background: Hemifacial spasm (HFS) is a movement disorder characterized by involuntary contractions of the muscles innervated by the facial nerve. Although most cases are caused by a vascular compression of the facial nerve (VII), others secondary causes should be considered when atypical neurological signs are present.

Case report: 64-year-old man with long-standing bilateral facial spasm associated with vertical nystagmus. Brain magnetic resonance imaging revealed Chiari type I malformation with compression of the VII and VIII cranial nerve roots.

Conclusion: This case highlights the importance of a detailed neurological examination in patients with hemifacial spasm, as associated signs may indicate underlying structural abnormalities that warrant neuroimaging. Recognizing such cases may help detect underlying causes and inform treatment decisions.