Hydrocephalus is a disorder of cerebral spinal fluid (CSF) physiology that results in increased intracranial pressure (ICP). It is commonly treated via surgical placement of a shunt in the ventricles to divert CSF. Diffuse optical measurements of cerebral perfusion and oxygen extraction were acquired before and after surgical shunt placement in neonates with hydrocephalus. An invasive ICP measurement was made at the time of shunt placement. Shunting increased cerebral perfusion and decreased oxygen extraction only in infants with elevated ICP. This suggests abnormally low perfusion in patients with elevated ICP, and normal perfusion in patients without elevated ICP.
We present pilot results on the validation of non-invasive assessment of elevated intracranial pressure with optical measurement of critical closing pressure. A strong correlation (r=0.85) between optical measurements of critical closing pressure and invasive measurements of intracranial pressure was observed in 5 infants with hydrocephalus, and 1 adult patient with diffuse hypoxic ischemic brain injury. By facilitating timely detection of intracranial hypertension, this approach has potential to reduce risk of brain damage in hydrocephalus and other vulnerable patient populations.