The role of repeated brain computed tomography based on ultrasound monitoring of optic nerve sheath diameter after moderate traumatic brain injury

Abstract

Objective This study was conducted to evaluate the association between changes in repeated brain computed tomography (CT) findings and the optic nerve sheath diameter (ONSD) determined by ocular ultrasonography in patients with moderate blunt traumatic brain injury (TBI). Methods This cross-sectional study was performed on patients with moderate blunt TBI (Glasgow Coma Scale, 9–12) who were referred to the emergency department during a 1-year period. Initially, all patients underwent a brain CT scan and primary ocular ultrasonography. Patients who were candidates for a second brain CT scan under observation in the emergency department also underwent a second ocular ultrasound. The primary outcome was the progression of brain lesions on repeated brain CT scans. Logistic regression and the area under receiver operating characteristic curve (AUC) were used. Results Overall, 204 patients with a mean age of 43±13.4 years were enrolled in the study. The study detected expanding changes in brain CT scans from 29 patients (14.2%). The progression of lesion on CT scan were significantly associated with changes in the Glasgow Coma Scale. In the second brain CT scan, there were significant associations between the progression of lesion on CT scan and the increased size of the ONSD measured on both axial and coronal sections (odds ratio, 17.3–47.5; AUC, 0.88–0.93). Conclusion Among patients with moderate TBI, an increase in ONSD on ocular ultrasound seems to be an appropriate criterion for repeating a brain CT scan to select a suitable therapeutic intervention.

Keywords

• hospital emergency service
• traumatic brain injuries
• ultrasonography