Figure 1.

Measured haemodynamic response to lumbar CSF infusion in the rabbit. ICP was increased over the period of 30 min from baseline levels (10 mm Hg) to high levels (>100 mm Hg). Cortical LDF (top panel) decreased with this increasing ICP, whereas Fv in the basilar artery remained stable until ICP was above 50 mm Hg. Mean arterial blood pressure increased when ICP increased above 30 mm Hg as part of the Cushing reflex.

LDF: laser Doppler flowmetry; Fv: flow velocity in the basilar artery; ABP: arterial blood pressure; CPP: cerebral perfusion pressure; ICP: intracranial pressure.