Volumetric quantification of brain swelling after hypobaric hypoxia exposure

István A. Mórocz, Gary P. Zientara, Hákon Gudbjartsson, Stephen Muza, Timothy Lyons, Paul B. Rock, Ron Kikinis, Ferenc A. Jólesz

Research output: Contribution to journalArticle

51 Scopus citations

Abstract

We applied a novel MR imaging technique to investigate the effect of acute mountain sickness on cerebral tissue water. Nine volunteers were exposed to hypobaric hypoxia corresponding to 4572 m altitude for 32 h. Such an exposure may cause acute mountain sickness. We imaged the brains of the volunteers before and at 32 h of hypobaric exposure with two different MRI techniques with subsequent data processing. (1) Brain volumes were calculated from 3D MRI data sets by applying a computerized brain segmentation algorithm. For this specific purpose a novel adaptive 3D segmentation program was used with an automatic correction algorithm for RF field inhomogeneity. (2) T2 decay rates were analyzed in the white matter. The results demonstrated that a significant brain swelling of 36.2 ± 19.6 ml (2.77 ± 1.47%, n = 9, P < 0.001) developed after the 32-h hypobaric hypoxia exposure with a maximal observed volume increase of 5.8% (71.3 ml). These volume changes were significant only for the gray matter structures in contrast to the unremarkable changes seen in the white matter. The same study repeated 3 weeks later in 6 of 9 original subjects demonstrated that the brains recovered and returned approximately to the initially determined sea-level brain volume while hypobaric hypoxia exposure once again led to a significant new brain swelling (24.1 ± 12.1 ml, 1.92 ± 0.96%, n = 6, P < 0.005). On the contrary, the T2 mapping technique did not reveal any significant effect of hypobaria on white matter. We present here a technique which is able to detect reversible brain volume changes as they may occur in patients with diffuse brain edema or increased cerebral blood volume, and which may represent a useful noninvasive tool for future evaluations of antiedematous drugs.

Original languageEnglish
Pages (from-to)96-104
Number of pages9
JournalExperimental Neurology
Volume168
Issue number1
DOIs
StatePublished - 1 Jan 2001

Keywords

  • Acute mountain sickness
  • Brain edema
  • Magnetic resonance imaging
  • Volumetric study

Fingerprint Dive into the research topics of 'Volumetric quantification of brain swelling after hypobaric hypoxia exposure'. Together they form a unique fingerprint.

  • Cite this

    Mórocz, I. A., Zientara, G. P., Gudbjartsson, H., Muza, S., Lyons, T., Rock, P. B., Kikinis, R., & Jólesz, F. A. (2001). Volumetric quantification of brain swelling after hypobaric hypoxia exposure. Experimental Neurology, 168(1), 96-104. https://doi.org/10.1006/exnr.2000.7596