Can Intraneural Perineuriomas Occur Intradurally? An Anatomic Perspective

Area of Science:

• Neuropathology
• Neurosurgery
• Radiology

Background:

• Intraneural perineuriomas are rare, benign tumors arising from perineurial cells.
• These tumors typically affect peripheral nerves in adolescents.
• No prior cases of classic intraneural perineurioma in an intradural location were identified in our experience.

Purpose of the Study:

• To investigate the possibility of intradural occurrence of intraneural perineuriomas.
• To correlate findings with the prevalence of other intradural nerve sheath tumors.
• To provide an anatomical explanation for observed tumor locations.

Main Methods:

• Retrospective review of 56 intraneural perineurioma cases from an institutional registry.
• Analysis of high-resolution magnetic resonance images for proximal extension to spinal nerves and roots.
• Comprehensive literature review and critical appraisal of potential intradural lesions.

Main Results:

• Of 56 patients, 15 (27%) had proximal tumors in the lumbosacral or brachial plexus.
• No cases were found proximal to the dorsal root ganglia (DRG).
• Literature search revealed no convincing intraspinal intradural perineuriomas, with only one possible intracranial intradural case.

Conclusions:

• Classic intraneural perineuriomas are exceedingly rare in an intradural location, if they occur at all.
• This rarity may be attributed to the limited number of perineurial cells at the nerve root level.
• Interactions between neuroglial cells at central-peripheral transition zones might also play a role.