Validating a threshold of ocular gaze deviation for the prediction of acute ischaemic stroke

Radiographic Horizontal Conjugate Gaze Deviation: Clinical Correlates

Purpose of Review

The potential diagnostic value of radiographic, horizontal, conjugate gaze deviation (Rad h-CGD) was first recognized in 2003 by Simon et al. Thereafter, interest grew related to its potential use as a marker of different neurologic and vestibular disorders. Over the past 20 years, we have identified clinical correlates of Rad h-CGD including those caused by supratentorial and infratentorial lesions. We propose clinicians and radiologists will better diagnose and manage patients by knowing the different diagnostic possibilities for Rad h-CGD.

Findings

We report different clinical correlates of Rad h-CGD relevant for localizing and lateralizing lesions. We measured the angle of deviation and correlated it with the clinical findings and underlying mechanisms. We then reviewed important data from the previous literature relevant to the localization of each lesion and combined it with our experience into the design of a practical algorithm to interpret Rad h-CGD.

Summary

Using Rad h-CGD provides useful information about the diagnosis and localization and may reveal subtle ocular findings not clear on physical examination. However, Rad h-CGD alone cannot distinguish between supratentorial and infratentorial lesions, and therefore, the clinical context is critical. Moreover, although Rad h-CGD occurs with strokes due to large vessel occlusion, it could also be seen with an acute vestibular syndrome, secondary to a peripheral vestibular neuritis. Other possibilities include ischemic events in the cerebellum, brainstem, and labyrinth.

Design and validation of a recognition instrument-the stroke aid for emergency scale-to predict large vessel occlusion stroke

Background and purpose: Rapidly recognizing patients with large-vessel occlusion stroke (LVOS) and transferring them to a center offering recanalization therapy is crucial of maximizing the benefits of early treatment. We therefore aimed to design an easy-to-use recognition instrument for identifying LVOS.

Methods: Prospective data were collected from emergency departments of 12 stroke-center hospitals in China during a 17-month study period. The Stroke Aid for Emergency (SAFE) scale is based on consciousness commands, facial palsy, gaze, and arm motor ability. Receiver operating characteristic analysis was used to obtain the area under the curve for the SAFE scale and previously established scales to predict LVOS.

Results: The SAFE scale could accurately predict LVOS at an accuracy rate comparable to that of the National Institutes of Health Stroke Scale (c-statistics: 0.823 versus 0.831, p = 0.4798). The sensitivity, specificity, positive predictive value, and negative predictive value for the SAFE scale were 0.6875, 0.8577, 0.6937, and 0.8542, respectively, with a cutoff point of 4. The SAFE scale also performed well in a subgroup analysis based on the patients’ ages, occluded vessel locations, and the onset-to-door times.

Conclusions: The SAFE scale can accurately recognize LVOS at a rate comparable to those of other, similar scales.

Does radiological conjugate eye deviation sign play a role in acute stroke imaging? A meta-analysis

BACKGROUND AND PURPOSE

The diagnostic value of non-contrast CT (NCCT) in acute stroke imaging remains indispensable, especially under emergency conditions with limited resources. The radiological conjugate eye deviation (RCED) has been demonstrated as a NCCT sign to predict acute ischemic stroke (AIS) or AIS secondary to large vessel occlusion (LVO) in recent studies. We performed a meta-analysis to gain a better understanding into the predictive role of RCED for AISs and LVO-AISs.

METHODS

We conducted a systematic literature search using PubMed, Embase, and Cochrane. The search focused on studies published between January 2000 and August 2020 that reported the predictive value of RCED for the diagnosis of AIS or LVO-AIS. Principal measurements of the meta-analysis were the overall sensitivity, specificity, the positive likelihood ratio (PLR), and the negative likelihood ratio (NLR) of RCED in predicting AIS and LVO-AIS.

RESULTS

We included 11 studies (n = 2304). For AIS, RCED had a sensitivity of 0.37 (95% CI 0.27-0.47), a specificity of 0.86 (95% CI 0.73-0.93), the area under the receiver operating characteristic curve (AUC) was 0.58 (95% CI 0.53-0.62), PLR was 2.5 (95% CI 1.5-4.4), and NLR was 0.74 (95% CI 0.65-0.84). For LVO-AIS, RCED had a sensitivity of 0.63 (95% CI 0.46-0.77), a specificity of 0.77 (95% CI 0.71-0.82), AUC was 0.63 (95% CI 0.46-0.77), PLR was 2.7 (95% CI 1.7-4.3), and NLR was 0.49 (95% CI 0.3-0.78).

CONCLUSION

RCED can be used to predict LVO-AIS. It is expected that this method will be extensively used and validated in acute stroke imaging, especially under emergency conditions with limited resources.

Bringing prevost's sign into the third dimension: Artificial intelligence estimation of conjugate gaze adjusted length (CGAL) and correlation with acute ischemic stroke

Conjugate gaze deviation is associated with acute ischemic stroke (AIS), although previously only measured on a 2D plane. The current study evaluates 3D imaging efficacy to assess conjugate gaze deviation and correlate direction and strength of deviation to neuro-clinical findings.A retrospective analysis of 519 patients who had CT scans for suspected AIS at our institution. Direction and angle of eye deviation were calculated based on 2D axial images. Volumetric reconstruction of CT scans allowed for calculation of 3D conjugate gaze adjusted length (CGAL). Angle, direction, and vector strength of both 2D and 3D scans were calculated by an artificial intelligence algorithm and tested for agreement with hemispheric ischemia location. CGAL measurements were correlated to NIHSS scores. Follow up MRI data was used to evaluate the sensitivity and specificity of CGAL in the identification of AIS.The final analysis included 122 patients. A strong agreement was found between 3D gaze direction and hemispheric ischemia location. CGAL measurements were highly correlated with NIHSS score (r = .72, P = .01). A CGAL >0.25, >0.28, and >0.35 exhibited a sensitivity of 91%, 86%, and 82% and specificity of 66%, 89%, and 89%, respectively, in AIS identification. A CGAL >0.28 has the best sensitivity-specificity balance in the identification of AIS. A CGAL >0.25 has the highest sensitivity.Given CED's correlation with NIHSS score a 1/4 deviation in the ipsilateral direction is a sensitive ancillary radiographic sign to assist radiologists in making a correct diagnosis even when not presented with full clinical data.

Prognostic information of gaze deviation in acute ischemic stroke patients

INTRODUCTION

Gaze deviation (GD) in acute ischemic stroke patients has been suggested to be associated with poor outcome and with the presence of large vessel occlusion. Our aim was to study the prognostic significance of GD in ischemic stroke patients submitted to acute revascularization treatments.

METHODS

Retrospective single-center study of consecutive anterior circulation ischemic stroke patients submitted to thrombolysis and/or endovascular revascularization between 2007 and 2017. The groups of patients with and without GD were compared concerning baseline clinical and imagiological variables, functional outcome at 3 months, and survival at 1 year.

RESULTS

Among a study population of 711 patients, 332 (46.7%) presented GD. Patients with GD were more frequently of female sex (p = 0.048), had higher baseline NIHSS scores (p < 0.001), had lower ASPECTS on baseline CT (p < 0.001), more frequently had ischemia of the right hemisphere (p < 0.001), presented higher NIHSS 24 hours after treatment (p < 0.001), and more frequently presented cardioembolic stroke (p = 0.003). In the unadjusted analyses, GD was associated with decreased 3-month functional independence and increased 1-month and 1 year mortality (p < 0.001). After adjustment for variables of interest, namely, for NIHSS 24 hours after treatment, GD was no longer associated with functional outcome or survival.

CONCLUSIONS

GD in patients with acute ischemic stroke is associated with increased clinical and imagiological severity at baseline. However, in patients submitted to acute revascularization treatments, this does not appear to be independent predictor of functional outcome or survival.

Conjugate Eye Deviation on CT Associated With Worse Outcomes Despite IV Thrombolysis

INTRODUCTION

Rapid stroke management has significant implications in patient outcomes. Ipsilateral computed tomography conjugate eye deviation (CT-CED) has been associated with worse outcomes but has never been evaluated as predictive of vascular occlusion. To test the hypothesis that CT-CED is a marker for vascular occlusion, we evaluated patients treated with intravenous tissue plasminogen activator (IV tPA).

METHODS

We performed a retrospective analysis of patients with acute ischemic stroke treated with IV tPA at a large tertiary care hospital over an 18-month period. A waiver of informed consent was granted. Two examiners evaluated baseline brain CTs blinded to the location of infarct to assess the presence of CT-CED and follow-up imaging for the location of infarct and the presence of intracranial large vessel occlusion. Demographics, initial National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scales (mRSs), and hospital length of stay (LOS) were collected.

RESULTS

Among 104 patients treated with IV tPA, 36 had CT-CED. Inter-rater reliability for CT-CED was excellent (κ = 0.97; 95% confidence interval: 0.98-1.0). The CT-CED group was older (69.8 vs 64 years; P = .038), had higher initial NIHSS (14.6 vs 11; P = .01), worse mRS (3.2 vs 2.4; P = .03), and longer LOS (8.4 vs 6.4; P = .05) compared with those without CT-CED. A vascular occlusion in the territory of the infarct was seen in 58% of patients with CT-CED versus 32% without CT-CED (P < .01). Atrial fibrillation (AF) was diagnosed in 61% patients with CT-CED versus 22% without (P < .01).

CONCLUSION

The CT-CED is associated with higher initial NIHSS, large vessel occlusion, and AF. Prospective studies are needed to ascertain whether CT-CED may be utilized part of a screen for endovascular therapy.

Association between eye position on brain scan and hospital mortality in acute intracerebral hemorrhage

BACKGROUND AND PURPOSE

Conjugate eye deviation (CED) and horizontal skew deviation are often seen in patients with intracerebral hemorrhage (ICH), but its prognostic significance is unclear. In this study, the association between brain scan assessed eye position and hospital mortality in patients with supratentorial ICH was tested.

METHODS

A retrospective analysis was performed in 316 patients with supratentorial ICH. Eye position was measured on first brain computed tomography or magnetic resonance imaging. Patients with CED, horizontal skew deviation or no deviation were distinguished. The association between eye position and hospital mortality was assessed using logistic regression analysis.

RESULTS

Conjugate eye deviation was present in 96 (30.4%), skew deviation in 44 (13.9%) and no deviation in 176 (55.7%) patients. In patients with CED, 81.3% had an eye position to the ipsilateral side of the hemorrhage. In univariable regression analysis, skew deviation was associated with mortality (odds ratio 3.10, 95% confidence interval 1.57-6.11; P = 0.001). In multivariable regression analysis, adjusting for age, ICH volume, intraventricular extension and Glasgow Coma Scale, eye position was not independently associated with mortality.

CONCLUSION

Horizontal skew eyes were found to be an unfavorable prognostic factor. However, this was not independent of other important predictors of ICH mortality and is most probably explained by its association with worse initial clinical presentation.