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http://dx.doi.org/10.3340/jkns.2020.0052

Secondary Neurulation Defects-1 : Retained Medullary Cord  

Kim, Kyung Hyun (Division of Pediatric Neurosurgery, Seoul National University Children's Hospital)
Lee, Ji Yeoun (Division of Pediatric Neurosurgery, Seoul National University Children's Hospital)
Wang, Kyu-Chang (Division of Pediatric Neurosurgery, Seoul National University Children's Hospital)
Publication Information
Journal of Korean Neurosurgical Society / v.63, no.3, 2020 , pp. 314-320 More about this Journal
Abstract
Retained medullary cord (RMC) is a relatively recent term. Pang et al. newly defined the RMC as a late arrest of secondary neurulation leaving a non-functional vestigial portion at the tip of the conus medullaris. RMC, which belongs to the category of closed spinal dysraphism, is a cord-like structure that is elongated from the conus toward the cul-de-sac. Because intraoperative electrophysiological confirmation of a non-functional conus is essential for the diagnosis of RMC, only a tentative or an assumptive diagnosis is possible before surgery or in cases of limited surgical exposure. We suggest the term 'possible RMC' for these cases. An RMC may cause tethered cord syndrome and thus requires surgery. This article reviews the literature to elucidate the pathoembryogenesis, clinical significance and treatment of RMCs.
Keywords
Secondary neurulation; Conus medullaris; Intraoperative electrophysiological monitoring; Closed spinal dysraphism; Tethered cord syndrome;
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