Predicting Prognosis of Mechanical Thrombectomy in Acute Ischemic Stroke Patients Using Modified DRAGON Score

Abstract

Background: The DRAGON score is reportedly useful for predicting the outcome of intravenous thrombolysis. This study tested whether the modified DRAGON (mDRAGON) score, in which the onset-to-treatment time is extended, can predict the long-term outcome of transient ischemic stroke (AIS) patients who are candidates for mechanical thrombectomy (MT). Methods: We assessed 40 AIS patients who were treated by MT alone or in combination with intravenous tissue plasminogen activator. The mDRAGON score is based on the following findings: hyperdense cerebral artery sign/early infarct signs on computed tomography (both=2, either=1, none=0), prestroke modified Rankin scale (mRS) score (>1=1), age (≥80 years=2, 65-79 years=1, <65 years=0), glucose level (>144 mg/dL=1), onset-to-treatment time (>230 minutes=1), and baseline National Institutes of Health Stroke Scale score (>15=3, 10-15=2, 5-9=1, 0-4=0). Receiver operating characteristics (ROC) curve analysis was used to compare the performance of the mDRAGON score with the performances of other stroke prediction scores. Results: Among 40 AIS patients treated with MT, the proportions with a good outcome (mRS score=0-2) in the groups with mDRAGON scores of 2 or 3, 4 or 5, 6 or 7, and 8-10 were 75%, 20%, 0%, and 0%, respectively, while the corresponding proportions with a poor outcome (mRS score=3-6) were 25%, 80%, 100%, and 100%. For the prediction of a good outcome at 3 months (mRS score=0-2), the area under the ROC curve of the mDRAGON scores was 0.87 (0.76-0.90). Conclusions: The mDRAGON score can be used to reliably predict the clinical outcome of AIS patients following endovascular treatment. Key Words: Stroke, Endovascular procedures, Prognosis