Assessing the Sensitivity of Cerebral Blood Flow and Oxygenation to High Intracranial Pressure with Near-Infrared Light
Abstract
Premature birth is associated with increased susceptibility to cerebral injuries because of the compounded effects of underdeveloped cerebral vascular and unstable hemodynamics. Notably, premature infants are highly vulnerable to intraventricular hemorrhage, which often leads to hydrocephalus and subsequently to high intracranial pressure (ICP). Current monitoring methods such as ultrasonography can only detect injuries that have already occurred, highlighting the need for prognostic tools. We hypothesize that concomitant measures of cerebral blood flow (CBF), blood oxygenation, and oxygen metabolism will be sensitive to high ICP. To test this hypothesis, experiments were conducted in a piglet model of high ICP using a noninvasive optical device that combines hyperspectral near-infrared spectroscopy and diffuse correlation spectroscopy. Measurements were acquired in nine piglets. Increases in ICP were associated with increases in deoxyhemoglobin and decreases in oxyhemoglobin, cerebral oxygenation, CBF, and cerebral perfusion pressure. These results demonstrated that optical measurements of CBF and cerebral oxygenation are sensitive to high ICP. The findings underscore the potential of optical techniques for non-invasive neuromonitoring in neonatal care, especially in the detection of compromised cerebral hemodynamics resulting from elevated ICP in cases of hydrocephalus.