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Optic nerve sheath diameter as a non-invasive tool to detect clinically relevant raised intracranial pressure in
Anmol Bansal1,2, Lokesh Kumar Tiwari3,2, Pradeep Kumar2
1Pediatrics, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India.
Insights
Optic nerve sheath diameter (ONSD) measurement via ultrasound effectively detects raised intracranial pressure (ICP) in children. A threshold of 4.46 mm demonstrated high sensitivity and specificity for identifying this critical condition in paediatric intensive care.
Area of Science:
- Pediatric critical care medicine
- Neurocritical care
- Diagnostic imaging in pediatrics
Background:
- Raised intracranial pressure (ICP) is a significant cause of admissions in pediatric intensive care units (PICU), necessitating prompt diagnosis to prevent severe outcomes.
- Early identification of elevated ICP is crucial for preventing brain herniation and mortality in pediatric patients.
Purpose of the Study:
- To evaluate the efficacy of optic nerve sheath diameter (ONSD) measurement using transorbital ultrasound in detecting clinically significant raised ICP in children.
- To establish a reliable diagnostic parameter for raised ICP in a pediatric intensive care setting.
Main Methods:
- An observational analytical study was conducted in a tertiary care Indian PICU involving children aged 2-14 years.
- Optic nerve sheath diameter (ONSD) was measured at three time points: day 1, day 2, and between days 4-7 of admission.
- ONSD values were compared between pediatric patients with and without clinical signs of raised ICP.
Main Results:
- Out of 137 recruited pediatric patients, 34 exhibited signs of raised ICP.
- Mean ONSD was significantly higher in children with raised ICP on all measurement days (Day 1: 4.99±0.57 vs 4.06±0.40; Day 2: 4.94±0.55 vs 4.04±0.40; Days 4-7: 4.48±1.26 vs 3.99±0.57; all p<0.01).
- A cutoff ONSD of 4.46 mm demonstrated 85.3% sensitivity and 86.4% specificity for detecting raised ICP, with an AUC of 0.906.
Conclusions:
- Transorbital ultrasound measurement of ONSD is a valuable tool for detecting clinically relevant raised ICP in children.
- An ONSD cutoff value of 4.46 mm provides excellent discriminatory performance for identifying raised ICP in the paediatric population.
Background:
Raised intracranial pressure (ICP) contributes to approximately 20% of the admissions in the paediatric intensive care unit (PICU) in our setting. Timely identification and treatment of raised ICP is important to prevent brain herniation and death in such cases. The objective of this study was to examine the role of optic nerve sheath diameter (ONSD) in detecting clinically relevant raised ICP in children.
Methods:
A hospital-based observational analytical study in a PICU of a tertiary care institute in India on children aged 2-14 years. ONSD was measured in all children on three time points that is, day 1, day 2 and between day 4 and 7 of admission. ONSD values were compared between children with and without clinical signs of raised ICP.
Results:
Out of 137 paediatric patients recruited, 34 had signs of raised ICP. Mean ONSD on day 1 was higher in children with signs of raised ICP (4.99±0.57 vs 4.06±0.40; p<0.01). Mean ONSD on day 2 also was higher in raised ICP patients (4.94±0.55 vs 4.04±0.40; p<0.01). The third reading between days 4 and 7 of admission was less than the first 2 values but still higher in raised ICP patients (4.48±1.26 vs 3.99±0.57; p<0.001). The cut-off ONSD value for detecting raised ICP was 4.46 mm on the ROC curve with an area under curve 0.906 (95% CI 0.844 to 0.968), 85.3% sensitivity and 86.4% specificity. There was no difference in ONSD between the right and the left eyes at any time point irrespective of signs of raised ICP.
Conclusion:
We found that measurement of ONSD by transorbital ultrasound was able to detect clinically relevant raised ICP with an excellent discriminatory performance at the cut-off value of 4.46 mm.
