Multifunctional optical coherence tomography: System development and application to the studies of functional hyperemia and cerebrovascular disease

Abstract

Quantitative hemodynamic analysis of functional hyperemia and cerebral blood flow was performed using high-speed optical coherence tomography angiography (OCTA) and Doppler OCT (D-OCT). OCTA provides detailed information of stimulus-induced hemodynamic response in the rodent brain. Temporal changes in vessel diameters and the propagation of retrograde vasodilation of pial artery were measured during hemodynamic stimulus response. An increase in the OCTA signal was also observed in multiple capillaries, which may imply that capillary blood flow increases as a result of the expanded arterial blood volume. D-OCT was performed to quantitatively measure stimulus-induced blood flow response in pial arteries. In addition, changes in microcirculation, such as capillary stalling, vessel density, and arterial blood flow, were quantitatively analyzed during pathological process using longitudinal OCTA and D-OCT. All these results suggest the potential utility of OCTA for the studies of functional hyperemia and cerebrovascular disease in normal and diseased brain.