Arterial hypertension in patients with left primary hemifacial spasm is associated with neurovascular compression of the left rostral ventrolateral medulla.

The aim of the study was to clarify the relationship between neurovascular compression of the rostral ventrolateral medulla and arterial hypertension in patients with primary hemifacial spasm. We enrolled 82 patients with primary hemifacial spasm and 82 age- and sex-matched magnetic resonance imaging (MRI) controls of the posterior cranial fossa. Neurovascular compression of the rostral ventrolateral medulla was assessed by MRI, and its association with arterial hypertension was investigated. No significant differences were found in prevalence of arterial hypertension between patients with primary hemifacial spasm and control subjects (39.0 vs. 29.3%, p=0.19). Thirty-two percent of the patients with left primary hemifacial spasm (n=44) and 47% of the patients with right primary hemifacial spasm (n=38) were hypertensive. Neurovascular compression of the left rostral ventrolateral medulla was observed in 86% of those with left (ipsilateral) primary hemifacial spasm with arterial hypertension (n=14) and 33% of those with left (ipsilateral) primary hemifacial spasm without (n=30). The association between neurovascular compression of the left rostral ventrolateral medulla and arterial hypertension was significant in patients with left (ipsilateral) primary hemifacial spasm (p=0.0012), but not in patients with right (contralateral) primary hemifacial spasm (p=0.18). Neurovascular compression of the left rostral ventrolateral medulla was more frequently observed in hypertensive patients with left primary hemifacial spasm, and neurovascular compression of the left rostral ventrolateral medulla correlated with arterial hypertension in these patients. These results are of potential clinical importance for the treatment of primary hemifacial spasm with arterial hypertension.