Multiparametric CT Phenotypes Identify Risks of Early Neurological Deterioration and 90-Day Disability in Minor Stroke

BackgroundMinor ischemic stroke is heterogeneous, and low NIHSS does not reliably identify patients at risk of deterioration or disability. We investigated whether integrating CT perfusion and angiographic vessel status identifies prognostically distinct phenotypes in a consecutive stroke-code cohort. MethodsWe analyzed consecutive adults with ischemic stroke, baseline NIHSS 0-5, prestroke modified Rankin Scale (mRS) [&le;]2, presentation within 24 hours of symptom onset or last known well, and emergency multiparametric CT. Patients were classified as no perfusion deficit/no vessel occlusion (PF-/VO-), perfusion deficit without visible occlusion (PF+/VO-), or perfusion deficit with vessel occlusion (PF+/VO+). The primary outcome was mRS [&ge;]3 at 90 days; early neurological deterioration (END), defined as an NIHSS increase [&ge;]2 points by 24 hours, was secondary. Multivariable logistic regression adjusted for prespecified covariates and additional variables associated with each outcome in univariable analysis. ResultsOf 2211 patients evaluated through the stroke-code pathway, 534 met inclusion criteria; 391 (73.2%) were PF-/VO-, 61 (11.4%) PF+/VO-, and 82 (15.4%) PF+/VO+. END occurred in 8.1% and mRS [&ge;]3 at 90 days in 17.6%. END occurred in 6.6%, 4.9%, and 17.1% of PF-/VO-, PF+/VO-, and PF+/VO+ patients, respectively (P=0.004), whereas mRS [&ge;]3 occurred in 13.3%, 34.4%, and 25.6%, respectively (P<0.001). Compared with PF-/VO-, PF+/VO+ was independently associated with END (adjusted odds ratio [aOR], 2.50 [95% CI, 1.03-6.06]), whereas PF+/VO- was independently associated with mRS [&ge;]3 at 90 days (aOR, 3.36 [95% CI, 1.67-6.73]). Findings were consistent across definitions of disabling versus nondisabling stroke and after exclusion of lacunar stroke. ConclusionsMultiparametric CT identified distinct risk phenotypes in minor ischemic stroke. Perfusion deficit without visible vessel occlusion was associated with 90-day disability, whereas combined perfusion deficit and vessel occlusion identified patients at increased risk of END. Tissue perfusion and vessel status may provide complementary information for acute risk stratification and future trial enrichment.