Analysis of the relationsii̇p between signs of increased intracranial pressure on brain computed tomography and optic nerve sheath diameter

Aim: This study aimed to evaluate the relationship between optic nerve sheath diameter (ONSD) and intracranial pressure (ICP) elevation and assess its potential as a non-invasive clinical marker. Additionally, differences in ONSD measurements between the right and left eyes and its association with age, sex, Glasgow Coma Scale (GCS), and mortality were examined. Material and Method: A retrospective analysis was conducted on 598 patients who presented to the Emergency Department of Cerrahpaşa Medical Faculty Hospital between January 1, 2020, and February 29, 2024, and underwent cranial CT imaging. Patients were classified into three groups: those with ICP-related CT findings, those with intracranial pathology without ICP elevation, and a control group. ONSD was measured using CT at 3 mm, 5 mm, and 8 mm posterior to the orbit. ROC curve analysis, AUC calculations, and statistical tests were used for data evaluation. Results: A significant correlation was found between ONSD and ICP elevation, age, and GCS (p<0.001). Cut-off values for ONSD at different distances were determined. However, ONSD was not a specific marker for ICP, as it was also elevated in other intracranial pathologies. No significant association was found between ONSD and mortality (p>0.05). Additionally, no difference was observed between ONSD values in the right and left eyes (p>0.05). Conclusion: ONSD measurement is a valuable non-invasive tool for assessing ICP elevation. However, its lack of specificity necessitates further large-scale, prospective studies to refine its clinical utility.