Hemifacial spasm in a patient with Marfan syndrome and Chiari I malformation. Case report.

Marfan syndrome, hemifacial spasm, and Chiari malformation are all relatively rare and seemingly separate entities. Marfan syndrome is caused by a defect in the gene that encodes fibrillin and leads to weakness of the artery wall. Hemifacial spasm results from compression of the facial nerve by an abnormal artery. Chiari malformation is characterized by a small posterior fossa. The authors report the case of a patient with Marfan syndrome who presented with hemifacial spasm and was also found to have a Chiari malformation Type I. The patient's Chiari malformation and hemifacial spasm were successfully treated by performing suboccipital and microvascular decompression surgeries, respectively. The pathophysiological characteristics of Marfan syndrome, hemifacial spasm, and Chiari malformation are discussed, and the authors propose a link between these conditions in this patient. The authors hypothesize that the patient's Marfan syndrome contributed to the abnormal shape of his vertebral artery and that, given the lack of space in his crowded posterior fossa due to the Chiari malformation, the artery caused compression of his facial nerve, resulting in hemifacial spasm.