Skip to main content
Advertisement

Main menu

  • Home
  • Content
    • Current Issue
    • Accepted Manuscripts
    • Article Preview
    • Past Issue Archive
    • Video Articles
    • AJNR Case Collection
    • Case of the Week Archive
    • Case of the Month Archive
    • Classic Case Archive
  • Special Collections
    • AJNR Awards
    • Low-Field MRI
    • Alzheimer Disease
    • ASNR Foundation Special Collection
    • Photon-Counting CT
    • View All
  • Multimedia
    • AJNR Podcasts
    • AJNR SCANtastic
    • Trainee Corner
    • MRI Safety Corner
    • Imaging Protocols
  • For Authors
    • Submit a Manuscript
    • Submit a Video Article
    • Submit an eLetter to the Editor/Response
    • Manuscript Submission Guidelines
    • Statistical Tips
    • Fast Publishing of Accepted Manuscripts
    • Graphical Abstract Preparation
    • Imaging Protocol Submission
    • Author Policies
  • About Us
    • About AJNR
    • Editorial Board
    • Editorial Board Alumni
  • More
    • Become a Reviewer/Academy of Reviewers
    • Subscribers
    • Permissions
    • Alerts
    • Feedback
    • Advertisers
    • ASNR Home

User menu

  • Alerts
  • Log in

Search

  • Advanced search
American Journal of Neuroradiology
American Journal of Neuroradiology

American Journal of Neuroradiology

ASHNR American Society of Functional Neuroradiology ASHNR American Society of Pediatric Neuroradiology ASSR
  • Alerts
  • Log in

Advanced Search

  • Home
  • Content
    • Current Issue
    • Accepted Manuscripts
    • Article Preview
    • Past Issue Archive
    • Video Articles
    • AJNR Case Collection
    • Case of the Week Archive
    • Case of the Month Archive
    • Classic Case Archive
  • Special Collections
    • AJNR Awards
    • Low-Field MRI
    • Alzheimer Disease
    • ASNR Foundation Special Collection
    • Photon-Counting CT
    • View All
  • Multimedia
    • AJNR Podcasts
    • AJNR SCANtastic
    • Trainee Corner
    • MRI Safety Corner
    • Imaging Protocols
  • For Authors
    • Submit a Manuscript
    • Submit a Video Article
    • Submit an eLetter to the Editor/Response
    • Manuscript Submission Guidelines
    • Statistical Tips
    • Fast Publishing of Accepted Manuscripts
    • Graphical Abstract Preparation
    • Imaging Protocol Submission
    • Author Policies
  • About Us
    • About AJNR
    • Editorial Board
    • Editorial Board Alumni
  • More
    • Become a Reviewer/Academy of Reviewers
    • Subscribers
    • Permissions
    • Alerts
    • Feedback
    • Advertisers
    • ASNR Home
  • Follow AJNR on Twitter
  • Visit AJNR on Facebook
  • Follow AJNR on Instagram
  • Join AJNR on LinkedIn
  • RSS Feeds

AJNR Awards, New Junior Editors, and more. Read the latest AJNR updates

LetterLetter

Pathogenesis of Syringomyelia

William C. Olivero
American Journal of Neuroradiology November 1999, 20 (10) 2024-2025;
William C. Olivero
M.D
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Info & Metrics
  • Responses
  • References
  • PDF
Loading

I read with great interest the article, The Presyrinx State: A Reversible Myelopathic Condition that May Precede Syringomyelia, by Nancy J. Fischbein et al (1). Although their theory of pathogenesis for the formation of the presyrinx state and syringomyelia is provocative, several areas need further clarification. The authors propose, as have others, that increased pressure in the subarachnoid space of the spinal canal in patients with Chiari malformation or other causes of relative blockage of CSF flow at the foramen magnum would cause the CSF to flow along the perivascular spaces and accumulate either in the central canal, causing syringomyelia, or in the cord substance itself, causing a “presyrinx” state. Nonetheless, as has been pointed out by others, increased pressure applied to a fluid (CSF) surrounding a distensible semisolid structure (the spinal cord) would have a tendency to compress that structure rather than force fluid into it (2). The only way there can be net flow of fluid into the spinal cord from the CSF surrounding it is if there is a pressure differential from the subarachnoid space to the central canal or to the spinal cord substance.

The authors state it has been proved that CSF flows from the subarachnoid space into the perivascular spaces of the spinal cord and from there along the interstitial spaces toward the central canal. For support of this, the authors reference Stoodley et al, among others (3). To summarize the experiment of Stoodley et al briefly, they injected horseradish peroxidase into the subarachnoid space of sheep and, by reducing arterial pulsations by ligating the brachiocephalic trunk, they demonstrated a reduction in the distribution of the horseradish peroxidase tracer through the perivascular spaces and central canal. They felt this experiment supported the hypothesis of arterial-driven flow of fluid from the subarachnoid space into the perivascular spaces across the interstitial space and into the central canal. In my opinion, however, this does not prove that there is bulk flow of fluid in that direction. It only proves that the cerebrospinal fluid is anatomically continuous with the central canal through a series of perivascular and interstitial spaces (4) and that when you impart energy (arterial pulsations) to a solid (horseradish peroxidase tracer) in solution (CSF) that solid will be distributed more rapidly and over a greater volume than if no energy is imparted to the mixture.

Liquids flow along the path of least resistance and from regions of high pressure to regions of low pressure. In order for there to be a net flow of fluid from the subarachnoid space through the very small (high resistance) perivascular and interstitial spaces into the very small (high resistance) central canal of the cord, and then possibly out the central canal at the level of the obex, there must be a significant pressure differential between the cerebrospinal fluid surrounding the spinal cord and the pressure in the central canal. Or, the resistance to flow from the subarachnoid space surrounding the spinal cord to the cisterna magna or basilar subarachnoid space must be greater than the combined resistances of the perivascular spaces, interstitial spaces, and central canal. This seems unlikely.

As we have previously proposed, we believe that the spinal cord is a net producer of extracellular fluid (5), and that this fluid normally flows along the perivascular spaces either into the subarachnoid space or possibly even into the central canal and is ultimately absorbed at the arachnoid villi with the rest of the CSF (6). We feel that increased resistance to flow at the foramen magnum by either Chiari I malformations or other causes prevents this extracellular fluid from exiting, and it accumulates in the spinal cord. This explanation appears more reasonable to us than the hypothesis that cerebrospinal fluid is somehow forced from the subarachnoid space through channels of very high resistance into the spinal cord and accumulates there.

References

  1. ↵
    Fischbein NJ, Dillon WP, Cobbs C, Weinstein PR, The “presyrinx” state: a reversible myelopathic condition that may precede syringomyelia. AJNR Am J Neuroradiol 1999;20:7-20
    Abstract/FREE Full Text
  2. ↵
    Cahan LD, Bentson JR, Considerations in the diagnosis and treatment of syringomyelia and the Chiari malformation. J Neurosurg 1982;57:24-31
    PubMed
  3. ↵
    Stoodley MA, Brown SA, Brown CJ, Jones NR, Arterial pulsation-dependent perivascular cerebrospinal fluid flow into the central canal in the sheep spinal cord. J Neurosurg 1997;86:686-693
    PubMed
  4. ↵
    Milhorat TH, Nakamura S, Heger IM, Nobanegani F, Murray S, Ultrastructural evidence of sink function of central canal of spinal cord as demonstration by clearance of horseradish peroxidase. Procedure, Electronic Microscope Society, America 1992;50:700-701
  5. ↵
    Sato O, Asai T, Amano Y, Hara M, Tsugane R, Yagi M, Extraventricular origin of the cerebrospinal fluid: formation rate quantitatively measured in the spinal subarachnoid space of dogs. J Neurosurg 1972;36:267-282
  6. ↵
    Olivero WC, Dinh Z, Chiari I malformation with traumatic syringomyelia and spontaneous resolution: case report and literature review. Neurosurgery 1992;30:758-760
    PubMed
  • Copyright © American Society of Neuroradiology
PreviousNext
Back to top

In this issue

American Journal of Neuroradiology
Vol. 20, Issue 10
1 Nov 1999
  • Table of Contents
  • Index by author
Advertisement
Print
Download PDF
Email Article

Thank you for your interest in spreading the word on American Journal of Neuroradiology.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Pathogenesis of Syringomyelia
(Your Name) has sent you a message from American Journal of Neuroradiology
(Your Name) thought you would like to see the American Journal of Neuroradiology web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Cite this article
William C. Olivero
Pathogenesis of Syringomyelia
American Journal of Neuroradiology Nov 1999, 20 (10) 2024-2025;

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
0 Responses
Respond to this article
Share
Bookmark this article
Pathogenesis of Syringomyelia
William C. Olivero
American Journal of Neuroradiology Nov 1999, 20 (10) 2024-2025;
del.icio.us logo Twitter logo Facebook logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • References
  • Info & Metrics
  • Responses
  • References
  • PDF

Related Articles

  • No related articles found.
  • PubMed
  • Google Scholar

Cited By...

  • No citing articles found.
  • Crossref
  • Google Scholar

This article has not yet been cited by articles in journals that are participating in Crossref Cited-by Linking.

More in this TOC Section

  • Reply:
  • Brain AVM’s Nidus: What if We Hadn’t Understood Anything?
  • Letter to the Editor regarding “Automated Volumetric Software in Dementia: Help or Hindrance to the Neuroradiologist?”
Show more LETTERS

Similar Articles

Advertisement

Indexed Content

  • Current Issue
  • Accepted Manuscripts
  • Article Preview
  • Past Issues
  • Editorials
  • Editor's Choice
  • Fellows' Journal Club
  • Letters to the Editor
  • Video Articles

Cases

  • Case Collection
  • Archive - Case of the Week
  • Archive - Case of the Month
  • Archive - Classic Case

More from AJNR

  • Trainee Corner
  • Imaging Protocols
  • MRI Safety Corner
  • Book Reviews

Multimedia

  • AJNR Podcasts
  • AJNR Scantastics

Resources

  • Turnaround Time
  • Submit a Manuscript
  • Submit a Video Article
  • Submit an eLetter to the Editor/Response
  • Manuscript Submission Guidelines
  • Statistical Tips
  • Fast Publishing of Accepted Manuscripts
  • Graphical Abstract Preparation
  • Imaging Protocol Submission
  • Evidence-Based Medicine Level Guide
  • Publishing Checklists
  • Author Policies
  • Become a Reviewer/Academy of Reviewers
  • News and Updates

About Us

  • About AJNR
  • Editorial Board
  • Editorial Board Alumni
  • Alerts
  • Permissions
  • Not an AJNR Subscriber? Join Now
  • Advertise with Us
  • Librarian Resources
  • Feedback
  • Terms and Conditions
  • AJNR Editorial Board Alumni

American Society of Neuroradiology

  • Not an ASNR Member? Join Now

© 2025 by the American Society of Neuroradiology All rights, including for text and data mining, AI training, and similar technologies, are reserved.
Print ISSN: 0195-6108 Online ISSN: 1936-959X

Powered by HighWire