Real-time EPI-based phase-contrast MRI for the measurement of cerebrovascular reactivity

Motivation: Cerebrovascular reactivity has emerged as one of the most promising biomarkers in vascular cognitive impairment and dementia (VCID), yet its measurement often requires CO2 inhalation and takes several minutes. Goal(s): To develop an EPI-based phase-contrast (PC) MRI as rapid cerebrovascular reactivity measurement that does not require CO2 inhalation. Approach: We validated EPI-based PC MRI with conventional cardiac-triggered acquisition. We demonstrated the ability of PC MRI in measuring cerebrovascular reactivity. Results: The results demonstrate that EPI-based PC MRI provides reliable CBF measurements when compared with conventional PC MRI. EPI PC MRI was able to measure cerebrovascular reactivity using both hypercapnia and breath-modulation challenges. Impact: This study could establish a quicker, more accessible real-time method for cerebrovascular reactivity assessment, improving early diagnosis and personalized monitoring of cerebrovascular conditions, especially for cognitive impairment and small vessel disease in clinical and research settings.