Related Experiment Video
Updated: Aug 25, 2025
Optic Nerve Sheath Point of Care Ultrasound: Image Acquisition
Published on: August 18, 2023
Optic nerve sheath diameter, intensive care unit admission and COVID-19-related-in-hospital mortality
1From the Department of Intensive Care Unit, Şırnak State Hospital, 73000 Şırnak, Turkey.
Insights
Optic nerve sheath diameter (ONSD) measured by ultrasonography can predict mortality in critical COVID-19 patients. Higher ONSD values at ICU admission indicate a greater risk of in-hospital death.
Area of Science:
- Critical care medicine
- Neurology
- Infectious disease
Background:
- Acute pulmonary failure in COVID-19 can cause hypoxia, hypercapnia, and increased intracranial pressure (ICP).
- ICP correlates with optic nerve sheath diameter (ONSD) measured via ultrasonography.
- Elevated ICP and ONSD are associated with poor prognosis in COVID-19 patients.
Purpose of the Study:
- To investigate the predictive capability of ONSD for in-hospital mortality in critically ill COVID-19 patients.
- To assess ONSD measurements taken upon intensive care unit (ICU) admission.
Main Methods:
- A cohort of 91 patients with critical COVID-19 was studied.
- Patients were divided into survivor (n=48) and nonsurvivor (n=43) groups.
- ONSD was measured using ultrasonography within 3 hours of ICU admission.
Main Results:
- Nonsurvivors had a significantly higher median ONSD (5.95 mm) compared to survivors (4.15 mm).
- Multivariate analysis showed ONSD was a significant predictor of in-hospital mortality (adjusted hazard ratio, 4.12).
- An ONSD cutoff of 5 mm demonstrated high accuracy (AUC 0.985, sensitivity 98%, specificity 90%) in predicting mortality. Patients with ONSD >5 mm had shorter median survival (11.5 days vs. 13.2 days).
Conclusions:
- ONSD ultrasonography is a valuable, inexpensive, and easily applicable method for early mortality prediction in critically ill COVID-19 patients.
- This non-invasive technique can aid in risk stratification and clinical decision-making upon ICU admission.
Background:
Hypoxia and hypercapnia due to acute pulmonary failure in patients with coronavirus disease 2019 (COVID-19) can increase the intracranial pressure (ICP). ICP correlated with the optic nerve sheath diameter (ONSD) on ultrasonography and is associated with a poor prognosis.
Aim:
We investigated the capability of ONSD measured during admission to the intensive care unit (ICU) in patients with critical COVID-19 in predicting in-hospital mortality.
Methods:
A total of 91 patients enrolled in the study were divided into two groups: survivor (n = 48) and nonsurvivor (n = 43) groups. ONSD was measured by ultrasonography within the first 3 h of ICU admission.
Results:
The median ONSD was higher in the nonsurvivor group than in the survivor group (5.95 mm vs. 4.15 mm, P < 0.001). The multivariate Cox proportional hazard regression analysis between ONSD and in-hospital mortality (contains 26 covariates) was significant (adjusted hazard ratio, 4.12; 95% confidence interval, 1.46-11.55; P = 0.007). The ONSD cutoff for predicting mortality during ICU admission was 5 mm (area under the curve, 0.985; sensitivity, 98%; and specificity, 90%). The median survival of patients with ONSD >5 mm (43%; n = 39) was lower than those with ONSD ≤5 mm (57%; n = 52) (11.5 days vs. 13.2 days; log-rank test P = 0.001).
Conclusions:
ONSD ultrasonography during ICU admission may be an important, cheap and easy-to-apply method that can be used to predict mortality in the early period in patients with critical COVID-19.
