Bedside ultrasonographic optic nerve sheath diameter for detecting raised intracranial pressure in children with acute encephalitis syndrome

BACKGROUND Raised intracranial pressure (ICP) is a potentially life-threatening complication of acute encephalitis syndrome (AES) in children.Early bedside recognition is important because invasive ICP monitoring may not be routinely available.AIM To evaluate the diagnostic performance of bedside ultrasonographic optic nerve sheath diameter (ONSD) for identifying computed tomography (CT) features suggestive of raised ICP in children with AES and to determine clinically useful ONSD cut-off values.METHODS This prospective analytical case-control study was conducted in the Pediatric Intensive Care Unit, King George's Medical University, Lucknow, from August 2019 to May 2020.A total of 82 children were enrolled, comprising 41 children with AES and 41 controls without central nervous system involvement.ONSD was measured ultrasonographically in both eyes 3 mm posterior to the papilla, and the mean of the right-and left-eye measurements was calculated.AES patients underwent CT brain imaging within 24 hours of ONSD assessment.Receiver operating characteristic (ROC)curve analysis was performed to assess the discriminatory performance of ONSD.Cutoff values representing three operating points (maximal sensitivity, sensitivity ≥ 80%, and specificity ≥ 75%) were selected from the ROC coordinates, and sensitivity, specificity, and predictive values were calculated with exact 95% confidence intervals (CIs).RESULTS