Reader Response: Teaching Video NeuroImage: Bilateral Hemifacial Spasm in Giant Cell Arteritis.

We read this case with interest, but we have some questions for the authors. The video demonstrates orbicularis and frontalis contraction occurring simultaneously on the left and right sides, with cheek contraction on the right side only. In our experience, patients with bilateral hemifacial spasm have contractions that are asynchronous left- and right-sided movements. The likelihood of a peripheral cause of bilateral hemifacial spasm producing identically timed synchronous contractions in both facial nerves seems very low. We are also unsure of the proposed mechanism of temporal arteritis for causing facial nerve irritation. A central cause with some asymmetry seems much more likely; we wonder if epileptic pathophysiology was explored, given the left-sided MRI-demonstrable cerebral ischemic predilection.