Noninvasive Detection of Elevated Intracranial Pressure Using Spectral Analysis of Tympanic Membrane Pulsation Signals

Neurological conditions such as hydrocephalus, traumatic brain injury, intracranial hemorrhage, and meningitis can lead to intracranial pressure (ICP) elevation, which is associated with serious complications, including severe headaches, blurred vision, problems with moving or talking, seizures, and even death [1]. Due to these potential risks, prompt medical attention and reliable monitoring may be needed for patients with elevated ICP. Current diagnosis relies on invasive pressure measurement. On the other hand, expensive imaging techniques like computed tomography and magnetic resonance imaging can also be used; however, they are not as reliable as invasive methods [2]. Unfortunately, the invasive methods pose the risk of infections and also require clinical expertise to perform. Important noninvasive methods to measure ICP that have been studied include observation of optic nerve sheath diameter variation, transcranial Doppler ultrasonography, and tympanic membrane displacement [3]. This study proposes a new noninvasive and easy-to-use method for the detection of elevated ICP by leveraging an apparent hydrostatic and mechanical pressure coupling between the ICP and the eardrum (tympanic membrane). According to an animal study [4], the cochlear aqueduct connects the subarachnoid space of the brain to the perilymphatic space of the cochlea of the inner ear, thus transmitting ICP pulsation to the tympanic membrane pulsation (TMp). As a result, TMp signals may provide useful information about the ICP level. Recently, cardiac pulse-based waveforms have been used to detect ICP noninvasively [5]. In this study, TMp signals, possibly originating from cardiac pulsations are used and spectral analysis of the signals is performed for elevated ICP detection.