Macular cherry red spot is an important diagnostic marker in children with myoclonic epilepsies
Received: 17 July 2016
Accepted: 04 October 2016
06 May 2018 (online)
Symptomatic myoclonus is the major presenting feature of a small but very important and genetically diverse group of rare disorders included under the umbrella of progressive myoclonus epilepsy (PME) and progressive myoclonus ataxia (PMA) syndromes. These disorders often require extensive investigations to arrive at an accurate diagnosis. We present a case series highlighting the importance of a detailed fundoscopic eye examination; particularly when occurring in conjunction with a clinical history of myoclonus, developmental regression and other systemic features in clinching an etiologic diagnosis of storage disorder, specifically, gangliosidosis and sialidosis in children with suspected progressive myoclonus epilepsies. The causes of macular cherry red spot (CRS) on fundoscopic examination are limited and in a given child may provide an important clue for narrowing the differential diagnoses and finally making an accurate diagnosis. Current literature on symptomatic myoclonus, cherry red spot and their occurrence in PME/PMA syndromes is also reviewed.
1 Current address: Department of Pediatric Neurology, Mazumdar Shaw Medical Center, Narayana Health City, Bengaluru 560099, Karnataka, India.
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