Near Infrared Spectroscopy as Possible Non-invasive Monitor of Slow Vasogenic ICP Waves

We aimed to study synchronisation between ICP and near infrared spectroscopy (NIRS) variables induced by vasogenic waves of ICP during an infusion study in hydrocephalic patients and after TBI. Nineteen patients presenting with hydrocephalus underwent a diagnostic intraventricular constant-flow infusion test. The original concept of the methodology, presented in the current paper, was derived from this material. Then the method was applied in 40 TBI patients, with results reported in an observational manner. During monitoring, NIRS deoxygenated and oxygenated haemoglobin (Hb, HbO2) were recorded simultaneously with ICP. Moving correlation coefficient (6 min) between Hb and HbO2 was tested as a marker of the slow vasogenic waves of ICP.