The effects of normobaric and hyperbaric oxygenation on MRI signal intensities in T1-weighted, T2-weighted and FLAIR images in human brain

• Published in: Radiology and oncology Vol. 57; no. 3; pp. 317 - 324
• Main Authors: Velej, Vida, Cankar, Ksenija, Vidmar, Jernej
• Format: Journal Article
• Language: English
• Published: Ljubljana Sciendo 01.09.2023; De Gruyter Poland
• Subjects: Brain; Caudate nucleus; Cerebrospinal fluid; Dissolved oxygen; human brain; hyperbaric oxygen; magnetic resonance; Magnetic resonance imaging; Medical imaging; Neuroimaging; normobaric oxygen; Oxygenation; Statistical analysis; Vitreous humour
• ISSN: 1318-2099; 1581-3207; 1581-3207; 0485-893X
• DOI: 10.2478/raon-2023-0043

Dissolved oxygen has known paramagnetic effects in magnetic resonance imaging (MRI). The aim of this study was to compare the effects of normobaric oxygenation (NBO) and hyperbaric oxygenation (HBO) on human brain MRI signal intensities.Baseline brain MRI was performed in 17 healthy subjects (mean age 27.8 ± 3.2). MRI was repeated after exposure to the NBO and HBO at different time points (0 min, 25 min, 50 min). Signal intensities in T1-weighted, T2-weighted images and fluid attenuated inversion recovery (FLAIR) signal intensities of several intracranial structures were compared between NBO and HBO.Increased T1-weighted signal intensities were observed in white and deep grey brain matter, cerebrospinal fluid (CSF), venous blood and vitreous body after exposure to NBO as well as to HBO compared to baseline (Dunnett's test, p < 0.05) without significant differences between both protocols. There was also no significant difference in T2-weighted signal intensities between NBO and HBO. FLAIR signal intensities were increased only in the vitreous body after NBO and HBO and FLAIR signal of caudate nucleus was decreased after NBO (Dunnett's test, p < 0.05). The statistically significant differences in FLAIR signal intensities were found between NBO and HBO (paired t-test, p < 0.05) in most observed brain structures (paired t-test, p < 0.05).Our results show that NBO and HBO alters signal intensities T1-weighted and FLAIR images of human brain. The differences between NBO and HBO are most pronounced in FLAIR imaging.