The ONSD/ETD ratio assessed six hours after cardiac arrest accurately forecasts neurological prognosis, especially for unfavorable results (CPC 4-5), and integration of various methodologies for dynamic evaluation enhances risk categorization and aids clinical decision-making for patients who attain ROSC.
The ONSD/ETD ratio at 6 hours post-ROSC was a robust predictor of unfavorable neurological outcomes, outperforming ONSD alone.
The ONSD/ETD ratio was a significant predictor of Cerebral Performance Category (CPC) scores.
All patients displaying cerebral circulatory arrest (CCA) waveforms or advancing to such waveforms on transcranial Doppler demonstrated a dismal neurological prognosis.
The change in Pulsatility Index (PI) of the middle cerebral artery was a borderline significant predictor of neurological outcome with high specificity.
The study collected multiple baseline and clinical variables alongside ultrasound parameters to enable comparative prognostic analysis.
This research suggests that a simple bedside ultrasound measurement taken just 6 hours after a patient's heart restarts (return of spontaneous circulation, or ROSC) can reliably predict whether that patient will have a poor neurological outcome. Specifically, the study found that the ratio of the optic nerve sheath diameter to the eyeball diameter (ONSD/ETD) — measured through the eyelid with ultrasound — was highly accurate, correctly identifying all patients who would have a poor outcome (100% specificity) and catching about 77% of those cases (76.5% sensitivity). This ratio performed better than measuring the optic nerve sheath diameter alone. The study also found that monitoring blood flow in the brain's middle cerebral artery using a technique called transcranial Doppler provided additional useful information. Patients who showed a specific abnormal blood flow pattern called 'cerebral circulatory arrest' waveforms all had poor neurological outcomes. A measure of how pulsatile the blood flow was (the Pulsatility Index) also showed promise as a predictor, with a high specificity of 100% at a particular threshold, though this finding was only borderline statistically significant. This research suggests that combining these two ultrasound-based approaches — eye ultrasound and brain blood flow monitoring — could help doctors make faster and more informed decisions about the care of cardiac arrest survivors shortly after their heart restarts. However, the study was small (49 patients) and retrospective, and the authors themselves caution that these findings are preliminary and need to be confirmed in larger studies before being widely adopted in clinical practice.
Wang K, Li G, Yang X, Ji M, Hong S, Liu C, et al.. (2026). Research on the use of bedside ultrasound to quickly evaluate neurological prognosis in patients with ROSC.. PloS one. https://doi.org/10.1371/journal.pone.0358243