The value of ultrasound measurement of optic nerve sheath diameter in predicting clinical prognosis and imaging outcomes in prehospital patients with spontaneous intracerebral hemorrhage.

Objective: Elevated intracranial pressure (ICP) is associated with poor prognosis in spontaneous intracerebral hemorrhage (sICH). Our study aims to assess ICP in sICH patients by measuring the optic nerve sheath diameter (ONSD) via ultrasound, and to explore whether prehospital ONSD measurement as a surrogate for ICP is associated with the clinical prognosis and imaging outcomes of sICH patients. Methods: This prospective study enrolled adult patients diagnosed with sICH upon emergency admission via prehospital care between January 2025 and December 2025. Ultrasound measurements of the ONSD were recorded at initial prehospital contact, post-departure in the ambulance, and upon hospital arrival. An ONSD ≥5 mm was defined as elevated ICP. We compared the in-hospital mortality rate, the proportion of early neurological deterioration (END), and the extent of hematoma expansion on imaging between the elevated ICP group and the normal ICP group. Regression analysis after adjusting for confounding factors was used to explore the relationship between ONSD and in-hospital mortality, END, and the extent of hematoma expansion on imaging in patients with sICH. Kaplan-Meier curves were used to analyze the survival probabilities of the two groups (ONSD ≥5 mm vs. ONSD < 5 mm). Results: A total of 186 patients were enrolled in this study, with a mean age of 62.8 ± 11.4 years. Among them, 112 patients (60.2%) were male. The ONSD ≥ 5 mm group had significantly higher rates of in-hospital mortality, END, and hematoma expansion compared to the ONSD < 5 mm group (all Conclusion: Among patients with acute sICH, elevated prehospital ONSD was associated with increased in-hospital mortality, END, hematoma expansion, and reduced patient survival.