Noninvasive intracranial pressure monitoring methods: a critical review

Abstract

Background: Intracranial pressure (ICP) monitoring has been used for decades in management of various neurological conditions. The gold standard for measuring ICP is a ventricular catheter connected to an external strain gauge, which is an invasive system associated with a number of complications. Despite its limitations, no noninvasive ICP monitoring (niICP) method fulfilling the technical requirements for replacing invasive techniques has yet been developed, not even in cases requiring only ICP monitoring without cerebrospinal fluid (CSF) drainage. Objectives: Here, we review the current methods for niICP monitoring. Methods: The different methods and approaches were grouped according to the mechanism used for detecting elevated ICP or its associated consequences. Results: The main approaches reviewed here were: physical examination, brain imaging (magnetic resonance imaging, computed tomography), indirect ICP estimation techniques (fundoscopy, tympanic membrane displacement, skull elasticity, optic nerve sheath ultrasound), cerebral blood flow evaluation (transcranial Doppler, ophthalmic artery Doppler), metabolic changes measurements (near-infrared spectroscopy) and neurophysiological studies (electroencephalogram, visual evoked potential, otoacoustic emissions). Conclusion: In terms of accuracy, reliability and therapeutic options, intraventricular catheter systems still remain the gold standard method. However, with advances in technology, noninvasive monitoring methods have become more relevant. Further evidence is needed before noninvasive methods for ICP monitoring or estimation become a more widespread alternative to invasive techniques.

Micro-/Nano-Structured Biodegradable Pressure Sensors for Biomedical Applications

“…Despite of the recent development in biodegradable pressure sensors, there are still some issues, such as sensitivity, operating range, and controllability of biodegradability, essentially to be improved for accurate pressure monitoring of various tissues and organs. In other words, regarding there are huge recent demands for healthcare and diagnosis of diseases in early stage through the pressure sensing of diverse tissues and organs, such as intracranial pressure [ 152 , 153 , 154 , 155 , 156 , 157 ], intraocular pressure [ 158 , 159 , 160 , 161 , 162 , 163 ], heartbeat [ 164 , 165 , 166 ], and bladder pressure [ 167 , 168 , 169 , 170 ], we expect that the high-performance biodegradable pressure sensors will be much more important for diverse biomedical applications in the future.…”

Molecular, Pathological, Clinical, and Therapeutic Aspects of Perihematomal Edema in Different Stages of Intracerebral Hemorrhage

“…Furthermore, it cannot accurately quantify the PHE volume. The main approaches, in addition to CT and MRI, for monitoring brain edema or PHE include the following: physical examination, indirect estimation of ICP (fundoscopy, displacement of the tympanic membrane, skull elasticity, and optic nerve sheath ultrasound), evaluation of cerebral blood flow (transcranial Doppler and Doppler of the ophthalmic artery), metabolic changes (near-infrared spectroscopy), and neurophysiological studies (electrical impedance tomography, electroencephalogram, visual evoked potential, and otoacoustic emission) [ 118 ]. Despite recent technological advances in various noninvasive techniques to monitor ICP, the current noninvasive standard does not replace invasive ones [ 119 ].…”

“…[ [117][118][119] Abbreviations: PHE: perihematomal edema; ICH: intracerebral hemorrhage; CT: computerized axial tomography; MRI: magnetic resonance imaging; EED: edema extension distance; rPHE: relative perihematomal edema; ICP: intracranial pressure.…”

From disease to noninvasive intracranial monitoring

“…These and other methods, as well as the advantages and limitations of each, are summarized in Table 1. The CSF tap test, a less invasive method, is also used widely in the clinical environment to determine ICP (cmH 2 O) [7][8][9][10] . In terms of noninvasive monitoring, several techniques have been developed, such as the use of transcranial Doppler, the measurement of the diameter of the optic nerve, and the use of biodegradable sensors.…”

“…In terms of noninvasive monitoring, several techniques have been developed, such as the use of transcranial Doppler, the measurement of the diameter of the optic nerve, and the use of biodegradable sensors. However, these methods all measure ICP indirectly [7][8][9] .…”