QUANTITATIVE pupillometry can predict neurological deterioration in patients with large middle cerebral artery (MCA) stroke, with changes detectable up to 12 hours before clinical decline.
This prospective, single-centre cohort study, conducted at Boston Medical Center between 2019 and 2024, explored whether longitudinal quantitative pupillometry could serve as an early predictor of neurological worsening in 71 patients with large MCA strokes. Researchers utilised the Neurological Pupil Index (NPi) and dilation velocity to assess time-dependent associations between pupillometric metrics and neurological deterioration. Adjustments were made for age, sex, and Alberta Stroke Program Early CT Scores to ensure accurate results.
Neurological decline was observed in 45.1% of patients, with a significant relationship between a 1-unit decrease in NPi and higher risk of deterioration (hazard ratio 2.46; 95% confidence interval 1.68–3.61). Dilation velocity was shown to improve prediction models compared to using NPi alone. Statistical analyses revealed that NPi scores were significantly lower at two intervals prior to deterioration: 0–2 hours (mean NPi 3.81 vs. 4.38, p = 0.001) and 2–4 hours (mean NPi 3.71 vs. 4.38, p < 0.001) compared to 10–12 hours before decline. Thresholds for deterioration were established at NPi <4.01, dilation velocity <0.49 mm/s, and a reduction of −0.15 in NPi over 12 hours.
These findings demonstrate that quantitative pupillometry offers a valuable tool for early detection of neurological deterioration in MCA stroke patients, allowing clinicians to identify patients at high risk of worsening and potentially intervene earlier. Incorporating metrics such as dilation velocity into clinical practice could enhance stroke management by refining predictive models and enabling targeted monitoring strategies. Future research should aim to validate these thresholds in broader populations and examine their utility in real-time decision-making within intensive care settings.
Katrina Thornber, EMJ
Reference
Du Y et al. Quantitative pupillometry predicts neurologic deterioration in patients with large middle cerebral artery stroke. Annals of Neurology. 2025;DOI:10.1002/ana.27178.
