Intracranial Air Absorption through Arachnoid Granulation: New Considerations from Transsphenoidal Surgery and Implications for Neurofluid Dynamics

Magn Reson Med Sci. 2025 Jan 1;24(1):144-147. doi: 10.2463/mrms.bc.2023-0122. Epub 2023 Nov 10.

Abstract

Postsurgery intracranial air usually diminishes, presumably merging with cerebrospinal fluid (CSF) and venous circulation. Our study presents two transsphenoidal surgery cases, highlighting potential air absorption by arachnoid granulation (AG)-an underexplored phenomenon. AG has long been deemed pivotal for CSF absorption, but recent perspectives suggest a significant role in waste clearance, neuroinflammation, and neuroimmunity. These cases may stimulate renewed research on the multifaceted role of AG in neurofluid dynamics and potentially elucidate further AG functions.

Keywords: arachnoid granulation; glymphatic; magnetic resonance imaging; pneumocephalus.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Air*
  • Arachnoid* / surgery
  • Female
  • Granulation Tissue / pathology
  • Humans
  • Magnetic Resonance Imaging / methods
  • Male
  • Middle Aged
  • Postoperative Complications

Grants and funding

This study was supported in part by a Grant-in-Aid for scientific research from the Japanese Society for the Promotion of Science (JSPS KAKENHI, grant number 23H02854) to S.N.