Timely detection of signs of raised intracranial pressure or persistent inflammation within the meninges can expedite therapeutic decisions improving the prognosis of patients with brain damage. Optic nerve ultrasonography provides a user-friendly, safe, low-cost, and non-invasive imaging method that can be easily deployed for ICU patient assessment. This study aims to evaluate the sensitivity and specificity of optic nerve ultrasound in estimating cerebral inflammation extension and cerebral edema in patients in the ICU. The working hypothesis is that optic nerve ultrasound is a useful tool in the rapid diagnosis of cerebral edema and the presence or persistence of cerebral inflammation, which can enable adapted and rapid therapeutic interventions.