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Secondary Neurulation Defects-1 : Retained Medullary Cord
Kyung Hyun Kim1, Ji Yeoun Lee1,2, Kyu-Chang Wang1
1Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul, Korea.
Journal of Korean Neurosurgical Society
|April 28, 2020
Summary
Retained medullary cord (RMC) is a congenital condition resulting from arrested secondary neurulation. This review clarifies RMC
Area of Science:
- Neuroscience
- Developmental Biology
- Pediatric Surgery
Background:
- Retained medullary cord (RMC) is a recently defined entity within closed spinal dysraphism.
- It represents a late arrest of secondary neurulation, resulting in a non-functional cord-like structure at the conus medullaris tip.
Purpose of the Study:
- To review the existing literature on retained medullary cords.
- To elucidate the pathoembryogenesis, clinical significance, and treatment of RMCs.
Main Methods:
- Literature review of retained medullary cord (RMC) cases.
- Analysis of diagnostic challenges and proposed terminology ('possible RMC').
Main Results:
- RMC is characterized by a vestigial portion at the conus medullaris tip.
- Intraoperative electrophysiological confirmation is crucial for definitive diagnosis.
- Tentative diagnoses are often made preoperatively or with limited surgical exposure.
Conclusions:
- RMC is a form of closed spinal dysraphism with potential to cause tethered cord syndrome.
- The term 'possible RMC' is proposed for cases with tentative or assumptive diagnoses.
- Surgical intervention is indicated for RMCs causing tethered cord syndrome.
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