Figure 3.
Imaging cerebral autoregulation at the microvascular spatial scale: Data from “microvascular-scale” in vivo optical imaging illustrating the autoregulatory hemodynamic response of the cerebrovasculature. (a) Laser speckle contrast (LSC) derived “baseline” or “resting” cerebral blood flow (CBFrest) map computed from the average over the first 2 min during room air breathing. (b) Time courses illustrating relative in vivo changes in deoxyhemoglobin (red trace) and CBF (green trace) in response to carbogen (95% O2, 5% CO2) inhalation. The carbogen inhalation (i.e. “Stim”) is shown as a solid black pulse train. The waveforms shown correspond to the 20 × 20 pixel ROI indicated by the red box in (a). Maps of (c) peak CBF response (CBFmax) and (d) the maximal change in deoxyhemoglobin (-ΔdHbmax) in response to the carbogen challenge. Scale and color bars are shown where appropriate.