Noninvasive Estimation of Pulsatile and Static Intracranial Pressure by Optical Coherence Tomography

To explore the ability of optical coherence tomography (OCT) to noninvasively estimate pulsatile and static intracranial pressure (ICP).

An OCT examination was performed in patients who underwent continuous overnight monitoring of the pulsatile and static ICP for diagnostic purpose. We included two patient groups, patients with idiopathic intracranial hypertension (IIH; n = 20) and patients with no verified cerebrospinal fluid disturbances (reference; n = 12). Several OCT parameters were acquired using spectral-domain OCT (RS-3000 Advance; NIDEK, Singapore). The ICP measurements were obtained using a parenchymal sensor (Codman ICP MicroSensor; Johnson & Johnson, Raynham, MA, USA). The pulsatile ICP was determined as the mean ICP wave amplitude (MWA), and the static ICP was determined as the mean ICP.

The peripapillary Bruch's membrane angle (pBA) and the optic nerve head height (ONHH) differed between the IIH and reference groups and correlated with both MWA and mean ICP. Both OCT parameters predicted elevated MWA. Area under the curve and cutoffs were 0.82 (95% confidence interval [CI], 0.66-0.98) and -0.65° (sensitivity/specificity; 0.75/0.92) for pBA and 0.84 (95% CI, 0.70-0.99) and 405 µm (0.88/0.67) for ONHH. Adjusting for age and body mass index resulted in nonsignificant predictive values for mean ICP, whereas the predictive value for MWA remained significant.

This study provides evidence that the OCT parameters pBA and ONHH noninvasively can predict elevated pulsatile ICP, represented by the MWA.

OCT shows promise as a method for noninvasive estimation of ICP.