Abstract
Introduction: The use of portable imaging techniques such as ultrasound and the consideration of sensitive
and reliable parameters for the evaluation of traumatic brain lesions, such as optic nerve sheath diameter
(ONSD) can be considered to detect traumatic brain lesions.
Objectives: The aim of this study was to examine the diagnostic value of ONSD measured by ultrasonography
(USG) (in comparison with CT scan) for early detection of pathological brain injuries following mild brain
trauma.
Patients and Methods: This cross-sectional study was conducted on patients aged more than 18 years
referred with the history of mild brain trauma to emergency departments at one of the three general hospitals
in Tehran between April 2016 and September 2017. The patients were evaluated by USG immediately after
admission and the ONSD value was measured. The patients were then referred for brain CT scanning.
Results: The right and the left ONSD values were significantly higher in patients with brain hemorrhage as
compared to those without this event. Similarly, those patients with brain contusion on CT had significantly
higher mean right and left ONSD as compared with those without contusion. The best cutoff value of the
right ONSD was 5.0 (yielding a sensitivity of 100% and a specificity of 90.4%) and the value for the left
ONSD as 4.7 (with a sensitivity of 100% and a specificity of 87.5%) for predicting cerebral hemorrhage.
Similarly, the best cutoff value of the right ONSD was 4.6 (with a sensitivity of 100% and a specificity of
86.5%) and the value for the left ONSD was 5.0 (with a sensitivity of 100% and a specificity of 90.4%) for
predicting contusion.
Conclusion: USG can detect traumatic lesions of the brain including hemorrhage and brain contusion with
high sensitivity and precision. In this regard, upon the referral of patients with a variety of traumatic brain
tumors, even mild traumas, the ONSD assessment by ultrasound can provide very comprehensive and
valuable information on the presence and development of traumatic brain injuries.