Department of Neurosurgery (J.Y.Y., K.J., J.V.C., J.O., G.J.Z.), Washington University in St. Louis School of Medicine, St Louis, MO.
Department of Neurology (Y.C., A.K., Z.Z., W.Y.A., M.A., G.J.Z., R.D.), Washington University in St. Louis School of Medicine, St Louis, MO.
Stroke. 2021 Apr;52(4):1380-1389. doi: 10.1161/STROKEAHA.120.032001. Epub 2021 Feb 16.
Early brain injury may be a more significant contributor to poor outcome after aneurysmal subarachnoid hemorrhage (aSAH) than vasospasm and delayed cerebral ischemia. However, studying this process has been hampered by lack of a means of quantifying the spectrum of injury. Global cerebral edema (GCE) is the most widely accepted manifestation of early brain injury but is currently assessed only through subjective, qualitative or semi-quantitative means. Selective sulcal volume (SSV), the CSF volume above the lateral ventricles, has been proposed as a quantitative biomarker of GCE, but is time-consuming to measure manually. Here we implement an automated algorithm to extract SSV and evaluate the age-dependent relationship of reduced SSV on early outcomes after aSAH.
We selected all adults with aSAH admitted to a single institution with imaging within 72 hours of ictus. Scans were assessed for qualitative presence of GCE. SSV was automatically segmented from serial CTs using a deep learning-based approach. Early SSV was the lowest SSV from all early scans. Modified Rankin Scale score of 4 to 6 at hospital discharge was classified as a poor outcome.
Two hundred forty-four patients with aSAH were included. Sixty-five (27%) had GCE on admission while 24 developed it subsequently within 72 hours. Median SSV on admission was 10.7 mL but frequently decreased, with minimum early SSV being 3.0 mL (interquartile range, 0.3-11.9). Early SSV below 5 mL was highly predictive of qualitative GCE (area under receiver-operating-characteristic curve, 0.90). Reduced early SSV was an independent predictor of poor outcome, with a stronger effect in younger patients.
Automated assessment of SSV provides an objective biomarker of GCE that can be leveraged to quantify early brain injury and dissect its impact on outcomes after aSAH. Such quantitative analysis suggests that GCE may be more impactful to younger patients with SAH.
与血管痉挛和迟发性脑缺血相比，早期脑损伤可能是导致蛛网膜下腔出血（aSAH）后预后不良的更重要因素。然而，由于缺乏量化损伤谱的方法，研究这一过程受到了阻碍。全脑肿胀（GCE）是早期脑损伤最广泛接受的表现，但目前仅通过主观、定性或半定量手段进行评估。侧脑室上方的脑脊液体积（SSV）已被提出作为 GCE 的定量生物标志物，但手动测量非常耗时。在这里，我们实施了一种自动算法来提取 SSV，并评估 GCE 减少与 aSAH 后早期结果之间的年龄相关性。
我们选择了在发病后 72 小时内有影像学检查的单一机构收治的所有成年 aSAH 患者。评估 GCE 的定性存在。使用基于深度学习的方法从连续 CT 中自动分割 SSV。早期 SSV 是所有早期扫描中最低的 SSV。出院时改良Rankin 量表评分 4-6 分被归类为预后不良。
共纳入 244 例 aSAH 患者。65 例（27%）入院时存在 GCE，24 例在 72 小时内发生 GCE。入院时 SSV 的中位数为 10.7 mL，但经常减少，最小早期 SSV 为 3.0 mL（四分位间距，0.3-11.9）。早期 SSV 低于 5 mL 高度预测定性 GCE（受试者工作特征曲线下面积，0.90）。早期 SSV 减少是不良预后的独立预测因素，在年轻患者中作用更强。
SSV 的自动评估提供了 GCE 的客观生物标志物，可用于量化 aSAH 后早期脑损伤并剖析其对结局的影响。这种定量分析表明，GCE 可能对年轻的 aSAH 患者影响更大。
