Abstract
Introduction
A retained medullary cord (RMC) is a rare dysraphic malformation, recently described as a late arrest of secondary neurulation. RMC is also a severely tethering lesion. The critical role of intraoperative neurophysiology to safely manage a RMC has been only anecdotally reported.
Case report
We describe the case of a RMC in a 1.5-year-old child with Currarino syndrome. At surgery, an apparently normal-looking spinal cord, stretched and tethered by a lipoma to the level of S2-S3, was observed. The border between the functional conus and the non functional RMC was defined through neurophysiological mapping. The cord was sharply interrupted at this level and untethered. A specimen was sent for pathology, which confirmed the presence of glial and neural elements. The post-operative neurological exam was normal.
Conclusion
Neurosurgical procedure for RMC should only be rendered with intraoperative neurophysiological mapping, as the anatomical judgment would not suffice to allow a safe cutting of these “normal-looking” neural structures.
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Abbreviations
- RMC:
-
Retained medullary cord
- ION:
-
Intraoperative neurophysiology
- SEPs:
-
Somatosensory-evoked potentials
- mMEPs:
-
Muscle motor-evoked potentials
- BCR:
-
Bulbocavernosus reflex
- CMAPs:
-
Compound muscle action potentials
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Sala, F., Barone, G., Tramontano, V. et al. Retained medullary cord confirmed by intraoperative neurophysiological mapping. Childs Nerv Syst 30, 1287–1291 (2014). https://doi.org/10.1007/s00381-014-2372-0
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DOI: https://doi.org/10.1007/s00381-014-2372-0