Method and apparatus for monitoring local cerebral physiology

Abstract

An apparatus for continuous monitoring of cerebral blood flow and intracranial pressure for substantially the same local region of cerebral tissue. A combined probe includes an elongated housing member that contains an ICP probe and a single optical fiber LDF microprobe. The LDF probe and the ICP probe are situated adjacent to each other within the elongated housing member, and preferably their respective intracranial ends are flush with the distal end of the elongated housing member. In addition, the combined probe is adapted to cooperate with an intracranial access system for securing the combined probe, and mitigating movement artifacts. In another embodiment, a combined probe includes a tissue oxymetry probe thus providing both metabolic and hemodynamic information for the same locus of cerebral tissue, and may be used for measuring a local cerebral metabolic rate. Another embodiment of the present invention provides a probe structure that includes a plurality of LDF microprobes for measuring CBF at spatially separate locations. In accordance with the present invention, a system and methods based on multi-modality monitoring, including monitoring of CBF and ICP for the same locus of cerebral tissue, are provided for measuring and assessing physiological processes and parameters including: autoregulation, cerebral vascular resistance (CVR), and carbon dioxide (CO.sub.2) reactivity.