Prefrontal Cortex Oxygenation Dynamics During Walking in Patients with Acute Stroke

This study aimed to elucidate the cerebral oxygenation dynamics during walking in patients with acute stroke. Participants were required to walk for 70 s while measurements of oxy-hemoglobin (O₂Hb), deoxy-hemoglobin (HHb), and total hemoglobin (THb) in the prefrontal cortex (PFC) were obtained using near-infrared spectroscopy. The Friedman test and Wilcoxon signed-rank tests with Bonferroni correction were applied to determine the oxygenation dynamics within the PFC during the task, making comparison to the pre-walking baseline at 10 s prior to walking onset. Analysis of 50 acute stroke patients (post-stroke onset: 8.7 [3.3] days) revealed significant main effects for O₂Hb, HHb, and THb (p < 0.001 for all). Post hoc analyses further revealed that O₂Hb significantly decreased at 40 s post walking onset, while HHb significantly increased at 45 s, and THb significantly decreased from 35 s (p < 0.05). These findings indicate that ischemia and vascular constriction in the PFC may occur during walking in the acute phase of stroke. However, the lack of a control group and the sole focus on the PFC limit the generalizability of the study findings.