Functional MRI evaluation of hyperbaric oxygen therapy’s effect on hand motor recovery in a chronic post-stroke patient: a case report and physiological discussion

The objective of the case report was to evaluate a specific HBOT protocol as an effective treatment for stroke rehabilitation, specifically improving hand motor function in chronic post-stroke patients. Stroke is the second leading cause of long-term disability worldwide. About 80% of individuals with acute stroke present upper-limb motor impairment, and 50–60% will have persistent disability or weakness at the chronic phase. Impaired upper-limb motor function is highly associated with low self-care ability, limited mobility and poor quality of life. In recent years, there has been evidence of the neuroplasticity effects of HBOT, and HBOT was found to induce neuroplasticity in chronic stages, even years after brain injury. While the healthcare system is primarily focused on teaching patients to live with their impairments, this case report evaluates the effect of a specific hyperbaric oxygen therapy (HBOT) protocol on true stroke rehabilitation, specifically, improving upper-limb function. This case report studied motor task functional MRI (fMRI) activation and resting-state functional connectivity (rsFC) in a 61-year-old right-handed male patient who suffered hemiparesis and physical weakness in the right upper limb two years after his acute insult, pre- and post-treatment of 60 daily HBOT sessions. Motor functions were assessed at baseline and after the treatment using the Fugl–Meyer assessment (FMA) and the handgrip maximum voluntary contraction (MVC). Following the HBOT protocol, the patient’s FMA score improved from 17 (severe impairment) to 31 (moderate impairment), and there was an increase in fMRI activation in both the supplementary motor cortex (SMA) and the premotor cortex (PMA) bilaterally during trials involving the right hand. The lateralization index (LI) decreased from 1 to 0.63, demonstrating the recruitment of the contralesional hemisphere. The region of interest, ROI-to-ROI, analysis revealed increased post-intervention inter-hemispheric connectivity (P = 0.002) and a between-network connectivity increase (z-score: 0.35 ± 0.21 to 0.41 ± 0.21, P < 0.0001). Seed-to-voxel-based rsFC analysis using the right SMA as seed showed increased connectivity to the left posterior parietal cortex, the left primary somatosensory cortex and the premotor cortex. This case report provides additional insights into HBOT-induced brain plasticity and functional improvement in chronic post-stroke patients, and shows HBOT’s potential as an effective, valuable treatment option for those suffering with lingering symptoms after a stroke. This work was conducted by a research team at the Sagol Center for Hyperbaric Medicine and Research at Shamir Medical Center and Tel Aviv University, and published in Frontiers in Neurology. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.