External Validation of VAN, VES and LARIO Scales in Suspected Acute Stroke

Overview

In acute ischemic stroke, treatments include intravenous thrombolysis (IVT) and mechanical thrombectomy (MT). IVT is viable up to 4.5 hours post-stroke onset, while MT is applicable within 24 hours but primarily for large vessel occlusions. MT is specialized and performed in select stroke centers. Effective early triage improves neurological outcomes. Pre-hospital stroke severity assessment and direct transfers for MT are crucial. Although the National Institute of Health Stroke Scale (NIHSS) is widely recognized, its practicality is limited in emergency settings due to its complexity. Alternative scoring systems like LAMS, CPSS, and RACE have been introduced but have limitations. Recently developed scores, namely Vision, Aphasia, and Neglect (VAN), Ventura Emergency Large Vessel Occlusion (VES), and Large Artery Intracranial Occlusion Stroke Scale (LARIO), demonstrate promising diagnostic accuracy in pilot studies, suggesting potential benefits for early detection, appropriate triage, and better neurological outcomes

For acute ischemic stroke, time-dependent treatments include intravenous thrombolysis (IVT) and mechanical thrombectomy (MT). IVT can be considered in all patients with acute ischemic stroke within the first 4.5 hours after the last known well time. However, MT can only be applied within the first 24 hours in large vessel occlusions defined as acute occlusion of the intracranial internal carotid artery (ICA), proximal posterior, middle, and anterior cerebral arteries (respectively PCA, MCA, ACA), intracranial vertebral artery and/or basilar artery. However, MT can only be performed in stroke centers specialized in this area. Effective triage of large vessel occlusion and early application of emergency stroke protocols are associated with good neurological outcomes. In this sense, pre-hospital determination of stroke severity and direct transfer of patients requiring MT to the stroke center are recommended by current guidelines. It is important that the protocols used in pre-hospital and emergency department triage to determine stroke severity are easy to learn and apply, are repeatable, and their accuracy is proven with external data sets. To date, many scoring systems have been proposed for early determination of stroke severity. Although the most accepted and widely used system among these systems is the National Institute of Health Stroke Scale (NIHSS), the need for training and experience for practitioners and the time-consuming application restrict its use in pre-hospital or emergency department triage. Alternatively, short and easily applicable systems such as The Los Angeles Motor Scale (LAMS), The Cincinnati Prehospital Stroke Scale (CPSS), Rapid Arterial oCclusion Evaluation (RACE) have been developed in the pre-hospital setting. However, the inability of these systems to provide high sensitivity and specificity together has necessitated the development of other alternative scoring systems. Among the new scoring systems developed in recent years, the Vision, Aphasia, and Neglect (VAN) score, the Ventura Emergency Large Vessel Occlusion (VES) score, and the Large Artery Intracranial Occlusion Stroke Scale (LARIO) have shown high diagnostic performance in pilot studies. The VAN score was shown to be 100% sensitive and 90% specific in predicting large vessel occlusion in stroke patients with motor weakness accompanied by at least one of the symptoms of vision, aphasia, and neglect or an NIHSS score of \>6. The VES score was developed as a 4-step system evaluating eye deviation, aphasia, neglect, and lethargy, and it was reported that the presence of at least one of these functions was 95% sensitive and 82% specific in predicting large vessel occlusion. The LARIO score was developed as a 5-step system evaluating facial paralysis, speech disorder, arm weakness, hand grip weakness, and neglect. Having \>3 of these steps positive provided 100% sensitivity and 82% specificity for large vessel occlusion. The results obtained from pilot studies suggest that the use of VAN, VES, and LARIO scoring systems in pre-hospital or emergency department triage promises to improve neurological outcomes by early identification of patients with large vessel occlusion requiring MT, appropriate triage, and optimal application of stroke protocols