Degree of Conjugate Gaze Deviation on CT Predicts Proximal Vessel Occlusion and May Expedite Endovascular Therapy

Recent trials have demonstrated superior outcomes with combination IV-tPA and endovascular therapy (EVT) within 6 hours of symptom onset in patients with proximal vessel occlusion (ICA, M1, or proximal M1/M2) compared to IV-tPA alone. The current standard of diagnosis for consideration of EVT is CT angiogram (CTA). Unfortunately, not all hospitals are equipped with CTA, and the decision to transfer to tertiary centers is often based on nonenhanced CT. Ipsilateral conjugate gaze deviation (CGD) is associated with worse outcomes and larger infarcts in acute ischemic stroke. We predicted that the more proximal the occlusion, the higher the degree of CGD.

Over a period of 12 months, 182 consecutive patients with acute ischemic stroke treated at our institution were prospectively analyzed. Stroke locations were categorized based on CTA. Average degree of CGD was measured. Patient demographics, ASPECTS, collateral score, National Institutes of Health Stroke Scale, modified Rankin Scale, TICI score, length-of-stay, and mortality were collected. The median follow-up was 30 days.

Out of ninety one of 182 patients with (+) CGD, 82 (90%) patients had ICA or middle cerebral artery (MCA) territory infarcts. The median was 25.0° in those with proximal occlusion and 13.7° in those with distal MCA occlusion (P < .001). A higher degree of CGD is positively correlated with proximity of vessel occlusion (correlation coefficient 0.2; P < .05). A cut-off greater than 20.25° (area under the curve = .76) showed a sensitivity of 64.0% and specificity 84.2%.

Measuring degree of CGD may help in early identification of proximal vessel occlusions and expedite transfer for clot retrieval.