PurposeTo review the underlying causes, diagnostic issues, and treatment of hemifacial spasm, with emphasis on advanced MRI techniques.MethodsBrief technical note.ResultsHigh-resolution T1- and T2-weighted spin-echo and/or gradient echo imaging of the posterior fossa should be performed with the use of intravenous gadolinium for maximum contrast between CSF, vessel, and nerve. Magnetic resonance angiography is often useful, and new state-of-the-art sequences provide more detail.ConclusionsAs MRI techniques improve, diagnosis and treatment of patients with hemifacial spasm will become easier. Ophthalmologists should be aware of these new magnetic resonance techniques.