RESUMO
Background: Magnetic resonance diffusion-weighted imaging (DWI) is the most sensitive modality for ischemic stroke diagnosis. However, DWI may fail to detect ischemic lesions in a proportion of patients. Methods: Following PRISMA statement, a systematic search of Medline, Embase, and Web of Science was conducted until January 3, 2024. The inclusion was confined to English literature with sufficient reporting. Proportions of DWI-negative ischemic stroke were pooled. For binary variables, odds ratios (ORs) were computed using the random-effects model. Results: Fourteen studies constituting 16,268 patients with a clinical diagnosis of ischemic stroke and available DWI findings were included. Intravenous thrombolysis (IVT) was administered to 19.6% of the DWI-negative group and 15.3% of the DWI-positive group. DWI-negative ischemic stroke was reported in 16% (95% CI: 10-24%; after sensitivity analysis: 11% [95% CI: 8-15%]) of stroke patients. Among minor stroke patients (National Institutes of Health Stroke scale [NIHSS] of 5 or less), 24% (95% CI 12-42%) had negative DWI findings. Predictors of DWI-negative scans included posterior circulation stroke, history of ischemic heart disease, prior stroke, or prior transient ischemic attack. Cardioembolic stroke (OR, 0.62, 95% CI: 0.41-0.93) and history of atrial fibrillation increased the likelihood of positive DWI findings (OR, 0.56, 95% CI: 0.45-0.71). Patients with DWI-negative ischemic stroke had higher odds of good functional outcomes (modified Rankin scale [mRS] of 0-1) (OR, 2.26; 95% CI: 1.03-4.92), lower odds of stroke recurrence (OR, 0.68; 95% CI: 0.48-0.96), and lower odds of severe disability or mortality (mRS of 3-6) (OR, 0.44; 95% CI: 0.34-0.57) compared to patients with positive DWI. Rates of symptomatic intracerebral hemorrhage after IVT were comparable between groups. Conclusion: DWI-negative findings were present in a significant proportion of ischemic stroke patients and may be utilized as a marker for favorable prognosis.
RESUMO
BACKGROUND: Minor ischemic stroke, defined as National Institute of Health Stroke Scale score of 0-5 on admission, represents half of all acute ischemic strokes. The role of intravenous alteplase (IVA) among patients with minor stroke is inconclusive; therefore, we evaluated clinical outcomes of these patients treated with or without IVA. MATERIALS AND METHODS: We searched Medline, Embase, Scopus, and the Cochrane library until August 1, 2023. Inclusion was restricted to the English literature of studies that reported on minor nondisabling stroke patients treated with or without IVA. Odds ratios (ORs) with their corresponding 95% CIs were utilized using a random-effects model. Efficacy outcomes included rates of excellent (modified Rankin scale [mRS] of 0-1) and good (mRS of 0-2) functional outcome at 90 days. The main safety outcome was symptomatic intracerebral hemorrhage (sICH). RESULTS: Five eligible studies, two RCTs and three observational studies, comprising 2764 patients (31.8% female) met inclusion criteria. IVA was administered to 1559 (56.4%) patients. Pooled analysis of the two RCTs revealed no difference between the two groups in terms of 90-days excellent functional outcomes (OR 0.76 [95% CI, 0.51-1.13]; I2 = 0%) and sICH rates (OR 3.76 [95% CI, 0.61-23.20]). No significant differences were observed between the groups in terms of good functional outcomes, 90-day mortality, and 90-day stroke recurrence. CONCLUSION: This meta-analysis of minor nondisabling stroke suggests that IVA did not prove more beneficial compared to no-IVA.
RESUMO
BACKGROUND AND PURPOSE: Isolated posterior cerebral artery occlusions (iPCAO) were underrepresented in pivotal randomized clinical trial (RCTs) of endovascular thrombectomy (EVT) in ischemic stroke, and the benefit of EVT in this population is still indeterminate. We performed a systematic review and a meta-analysis to compare the safety and efficacy of EVT compared to best medical management (BMM) in patients with iPCAO. METHODS: We searched Medline/PubMed, Embase, Web of Science, and the Cochrane databases up to May 2023 for eligible studies reporting outcomes of patients with iPCAO treated with EVT or BMM. We pooled odds ratios (ORs) with corresponding 95% confidence intervals (CI) using a random-effects model. RESULTS: Seven studies involving 2560 patients were included. EVT was associated with significantly higher likelihood of early neurological improvement (OR, 2.31 [95% CI, 1.38-2.91]; p < 0.00001) and visual field normalization (OR, 3.08 [95% CI, 1.76-5.38]; p < 0.0001) compared to BMM. Rates of good functional outcomes (mRS 0-2) were comparable between the two arms (OR, 0.88 [95% CI, 0.70-1.10]; p = 0.26). Symptomatic intracranial hemorrhage (sICH) was comparable between the two groups (OR, 1.94 [95% CI, 0.96-3.93]; p = 0.07). Mortality was also similar between the two groups (OR, 1.36; [95% CI, 0.77-2.42]; p = 0.29). CONCLUSIONS: In patients with iPCAO, EVT was associated with visual and early neurological improvement but with a strong trend toward increased sICH. Survival and functional outcomes may be slightly poorer. The role of EVT in iPCAO remains uncertain.
