# Effects of Hyperbaric Oxygen Therapy on Cerebral Activity in Stroke Patients Based on fNIRS

## TL;DR

This study explores how hyperbaric oxygen therapy affects brain activity in stroke patients using fNIRS, revealing changes in cerebral activation and potential benefits for recovery.

## Contribution

The study provides new insights into the neurophysiological effects of HBOT on cerebral activation in stroke patients using fNIRS.

## Key findings

- HBOT altered activation patterns in brain regions during motor tasks in stroke patients.
- Clinical improvements were observed in Brunnstrom stage, Fugl-Meyer scores, and daily living activities post-HBOT.
- HBOT may enhance cerebral blood flow, oxygenation, and neural repair in stroke patients.

## Abstract

Stroke remains a leading cause of death and disability worldwide, imposing significant burdens on patients, families, and healthcare systems. Despite advances in acute management and rehabilitation, effective interventions to promote neural recovery remain limited. Hyperbaric oxygen therapy (HBOT) has emerged as a potential adjunctive treatment, but its effects on cortical functional activity—particularly the neurophysiological mechanisms underlying clinical improvements—remain insufficiently understood. This study aimed to investigate the effects of hyperbaric oxygen therapy (HBOT) on cerebral activation in stroke patients using functional near-infrared spectroscopy (fNIRS) and to evaluate its therapeutic efficacy. A total of 23 patients with intracerebral hemorrhage and 20 with cerebral infarction were enrolled. fNIRS data were collected before HBOT and within 10–30 min after treatment completion. During data acquisition, participants performed an alternating left- and right-hand grip task while wearing the fNIRS device throughout the procedure. Changes in near-infrared light intensity were monitored to objectively reflect cortical activity. The results showed that after HBOT, activation patterns in relevant brain regions during the grip task were significantly altered: activation channels during the bilateral grip task changed in cerebral infarction patients, with some brain regions overlapping with those observed in intracerebral hemorrhage patients. In intracerebral hemorrhage patients, the number of significantly activated channels decreased during the left-hand grip task but increased notably during the right-hand grip task, which may be related to cerebral functional compensation and right-hand dominance. Clinical assessments revealed significant post-treatment improvements in Brunnstrom stage, Fugl-Meyer scores, and activities of daily living. These findings suggest that HBOT may contribute to multifaceted recovery of brain function in stroke patients, not only by enhancing cerebral blood flow and oxygenation but also by facilitating neural repair and regeneration, as well as optimizing cerebral activation and functional connectivity. Thus, this study provides an objective basis for understanding the mechanisms and efficacy of HBOT in stroke rehabilitation.