Department of Neurology, 65462Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
Department of Neurosurgery, 65462Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
Int J Stroke. 2021 Feb;16(2):163-171. doi: 10.1177/1747493019895703. Epub 2020 Jan 28.
Clot contraction reinforces hemostasis by providing an impermeable barrier and contractile force. Since computed tomography attenuation of intracerebral hemorrhage is largely determined by the density of red blood cells, clot contraction can be reflected in an increase of Hounsfield unit (HU) of hematoma.
We hypothesized that hematoma expansion is inversely associated with mean HU of intracerebral hemorrhage at presentation.
Eighty-nine consecutive spontaneous intracerebral hemorrhage patients with onset to first computed tomography within 24 h were included. Hematomas were segmented using semiautomated planimetry to measure the volume and mean HU. Hematoma expansion was defined as an increase in hematoma volume by over 33% or 6 mL. Multivariable logistic regression was performed for hematoma expansion. The discrimination power of mean HU for hematoma expansion was assessed using C-statistic.
The computed tomography attenuation of hematoma at presentation was 57.5 ± 3.3 HU and the volume was 16.9 ± 23.2 mL. Hematoma expansion occurred in 37.1% of patients. The computed tomography attenuation of hematoma was lower in patients with hematoma expansion than with no expansion (55.7 ± 2.9 HU vs. 58.6 ± 3.1 HU, p-value < 0.01). Multivariable logistic regression revealed that the mean HU of hematoma was inversely associated with hematoma expansion (adjusted odds ratio, 0.64; 95% confidence interval, 0.51-0.80). The C-statistic of the model with four known predictors increased from 0.66 to 0.84 after incorporating mean HU (p-value < 0.01).
Intracerebral hemorrhage with lower mean HU of hematoma at presentation is more likely to undergo hematoma expansion. This finding suggests the potential presence of clot contraction process that reinforces hemostasis in intracerebral hemorrhage.
血栓收缩通过提供不可渗透的屏障和收缩力来加强止血。由于颅内血肿的计算机断层扫描衰减主要由红细胞密度决定，因此血栓收缩可以反映为血肿的亨氏单位（HU）增加。
我们假设血肿扩大与发病后即刻颅内血肿的平均 HU 呈负相关。
纳入 89 例发病后 24 小时内行首次 CT 检查的连续自发性脑出血患者。使用半自动面积测量法对血肿进行分割，以测量血肿体积和平均 HU。血肿扩大定义为血肿体积增加超过 33%或 6 毫升。采用多变量逻辑回归分析血肿扩大。使用 C 统计量评估平均 HU 对血肿扩大的鉴别能力。
发病时血肿的 CT 衰减为 57.5±3.3HU，体积为 16.9±23.2mL。37.1%的患者发生血肿扩大。与无扩大组相比，扩大组的血肿 CT 衰减较低（55.7±2.9HU 与 58.6±3.1HU，p 值<0.01）。多变量逻辑回归显示，血肿的平均 HU 与血肿扩大呈负相关（调整后的优势比为 0.64；95%置信区间为 0.51-0.80）。在纳入平均 HU 后，包含四个已知预测因子的模型的 C 统计量从 0.66 增加到 0.84（p 值<0.01）。
发病时血肿平均 HU 较低的颅内血肿更有可能发生血肿扩大。这一发现提示血栓收缩过程可能存在于脑出血中，加强了止血作用。
