| Summary: | <p><strong>Background:</strong> Myoclonus–dystonia is a condition that manifests predominantly as myoclonic jerks with focal dystonia. It is genetically heterogeneous with most mutations in the epsilon sarcoglycan gene (<em>SGCE</em>). In medically refractory cases, deep brain stimulation (DBS) has been shown to provide marked sustainable clinical improvement, especially in <em>SGCE</em>-positive patients. We present two patients with myoclonus–dystonia (one <em>SGCE</em> positive and the other <em>SGCE</em> negative) who have the isolated myoclonus phenotype and had DBS leads implanted in the bilateral globus pallidus internus (GPi).</p> <p><strong>Methods:</strong> We review their longitudinal Unified Myoclonus Rating Scale scores along with their DBS programming parameters and compare them with published cases in the literature.</p> <p><strong>Results:</strong> Both patients demonstrated complete amelioration of all aspects of myoclonus within 6–12 months after surgery. The patient with the <em>SGCE</em>-negative mutation responded just as well as the patient who was <em>SGCE</em> positive. High-frequency stimulation (130 Hz) with amplitudes greater than 2.5 V provided therapeutic benefit.</p> <p><strong>Discussion:</strong> This case series demonstrates that high frequency GPi-DBS is effective in treating isolated myoclonus in myoclonus–dystonia, regardless of the presence of <em>SGCE</em> mutation.</p>
|
|---|
