Assessing prognostic value of optic nerve sheath diameter and Marshall computed tomography score in severe traumatic brain injury: A prospective study

Abstract

To study the role of Optic Nerve Sheath Diameter (ONSD) and computed tomography (CT) Marshall Grading in predicting outcome in severe Traumatic Brain Injury (TBI). All patients with severe TBI, following inclusion and exclusion criteria, were included. The patients were divided into two groups: the operative and nonoperative groups. Six-hourly ultrasonography (USG)-guided ONSDs were performed in both eyes over 96 hours. Marshall Grading of CT imaging was applied . Twenty-four male patients with severe TBI were part of the study. The AUROC for ONSD of the right side predicting intracranial pressure (ICP) more than 15 was 0.787 (95% CI: 0.727 - 0.847), while for the left side was 0.813 (95% CI: 0.757 - 0.869). The area under the receiver operating characteristic (ROC) curve (AUROC) for ONSD of the right side predicting ICP more than 22 was 0.927 (95% CI: 0.87 - 0.984), while for the left side was 0.939 (95% CI: 0.888 - 0.99). All results were statistically significant ( p <0.001). Combining ONSD >4.5 mm and Marshall grade >3 yielded a sensitivity of 61.5% and a specificity of 90.9% for predicting an ICP >15 mmHg, although the results were not statistically significant. Marshall score did not differ significantly between the discharge (mean 2.75 ± 1.00) and death (mean 3.00 ± 0.93) groups (W = 54.000, p = 0.536). ONSD assessment should be included in routine monitoring of patients with TBI. The initial CT scan findings alone can serve as a valuable predictor of elevated ICP; however, combining with ONSD measurements increases predictive accuracy.