Anterior ischemic stroke: Comparison of two clinical outcome prediction scores through the investigation of cerebral collaterals using multiphase CT angiography.

PURPOSE: To compare the evaluation of collaterals on multiphase computed tomography (CT) angiography using the score proposed by the reference study by Menon et al. and the Alberta Stroke Program Early CT (ASPECT) score for the prediction of favorable clinical outcome in patients with anterior ischemic stroke (IS). MATERIALS AND METHODS: Retrospective single center study including 199 patients with anterior ischemic stroke and evaluated using multiphase CT angiography. Collaterals were assessed using the reference score and ASPECT score. The early clinical outcome [National Institute of Health Stroke Score (NIHSS) over day 1] and later clinical outcome [90-day modified Rankin Scale (mRS)] were collected. The primary analysis related to the association between collateral scores and clinical outcome. RESULTS: Collaterals are an independent predictive factor of favorable clinical outcome with the two scores, ranging from an odds ratio (OR) [95% confidence interval (CI)] = 1.84 [1.23; 2.76], P = 0.003 for the reference score to an OR [95% CI] = 2.63 [1.21; 5.73], p = 0.015 for the phase 3 ASPECT score. The phase 3 ASPECT score offers better sensitivity (Se) for the prediction of a favorable clinical outcome [Se = 95%, specificity (Sp) = 37% for a threshold of 7/7] than the reference score (Se = 83%, Sp = 47% for a threshold of 4/5). CONCLUSION: This study demonstrates the value of the ASPECT score in analyzing collaterals using multiphase CT angiography for the prediction of clinical outcome.

Personalized mapping of the deep brain with a white matter attenuated inversion recovery (WAIR) sequence at 1.5-tesla: Experience based on a series of 156 patients.

OBJECTIVE: Deep brain mapping has been proposed for direct targeting in stereotactic functional surgery, aiming to personalize electrode implantation according to individual MRI anatomy without atlas or statistical template. We report our clinical experience of direct targeting in a series of 156 patients operated on using a dedicated Inversion Recovery Turbo Spin Echo sequence at 1.5-tesla, called White Matter Attenuated Inversion Recovery (WAIR). METHODS: After manual contouring of all pertinent structures and 3D planning of trajectories, 312 DBS electrodes were implanted. Detailed anatomy of close neighbouring structures, whether gray nuclei or white matter regions, was identified during each planning procedure. We gathered the experience of these 312 deep brain mappings and elaborated consistent procedures of anatomical MRI mapping for pallidal, subthalamic and ventral thalamic regions. We studied the number of times the central track anatomically optimized was selected for implantation of definitive electrodes. RESULTS: WAIR sequence provided high-quality images of most common functional targets, successfully used for pure direct stereotactic targeting: the central track corresponding to the optimized primary anatomical trajectory was chosen for implantation of definitive electrodes in 90.38%. CONCLUSION: WAIR sequence is anatomically reliable, enabling precise deep brain mapping and direct stereotactic targeting under routine clinical conditions.