The inferior medullary velum: Anatomical study and neurosurgical relevance ; Laboratory investigation

R. Shane Tubbs, Anand N. Bosmia, Marios Loukas, Eyas M. Hattab, Aaron Cohen-Gadol

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Object. Although it is often visualized surgically, details regarding the inferior medullary velum are lacking in the literature. The present study is intended to better elucidate this neuroanatomical structure using microsurgical and immunohistochemical analyses. Methods. To study the inferior medullary velum, the authors performed microdissection in 15 adult cadavers. Following gross study, specimens were examined histologically. Results. The inferior medullary velum extended from the flocculus to the middle cerebellar peduncle and stretched between the inferior cerebellar peduncle and the nodule and pyramid. The average thickness of the velum was found to be 0.5 mm (range 0.35-0.8 mm) and the average length was found to be 6 mm (range 5.5-7.2 mm). Arterial branches were identified in all specimens that arose from medullary branches of the posterior inferior cerebellar artery and supplied the inferior medullary velum. Histologically and from internal to external, a choroid plexus epithelium as a single cell layer was adjacent to a cuboidal layer of ependymal cells with no visible cilia. The next layer contained scattered glia in single cells or small clusters. The most external layer was composed of flat spindle cells resembling fibroblasts. No neurons of any type were identified. Only rare axons traversed the thin hypocellular zone that disappeared toward the midline. Conclusions. Based on this cadaveric study, the authors conclude that division of the inferior medullary velum should be relatively harmless as no neuronal cells were identified in this structure, which appears to be a vestigial bridge of tissue between the left and right sides of the cerebellum.

Original languageEnglish
Pages (from-to)315-318
Number of pages4
JournalJournal of Neurosurgery
Volume118
Issue number2
DOIs
StatePublished - Feb 2013

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Microdissection
Choroid Plexus
Cilia
Cadaver
Neuroglia
Cerebellum
Axons
Epithelium
Arteries
Fibroblasts
Neurons
Middle Cerebellar Peduncle

Keywords

  • Anatomy
  • Fourth ventricle
  • Inferior medullary velum
  • Medulloblastoma

ASJC Scopus subject areas

  • Clinical Neurology
  • Surgery

Cite this

The inferior medullary velum : Anatomical study and neurosurgical relevance ; Laboratory investigation. / Shane Tubbs, R.; Bosmia, Anand N.; Loukas, Marios; Hattab, Eyas M.; Cohen-Gadol, Aaron.

In: Journal of Neurosurgery, Vol. 118, No. 2, 02.2013, p. 315-318.

Research output: Contribution to journalArticle

Shane Tubbs, R. ; Bosmia, Anand N. ; Loukas, Marios ; Hattab, Eyas M. ; Cohen-Gadol, Aaron. / The inferior medullary velum : Anatomical study and neurosurgical relevance ; Laboratory investigation. In: Journal of Neurosurgery. 2013 ; Vol. 118, No. 2. pp. 315-318.
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