目的: 观察创伤性脑损伤(traumatic brain injury, TBI)大鼠急性期创伤半暗带内微血管损伤与修复的动态变化。方法: 重物坠落致去颅骨骨瓣大鼠TBI后置入封闭式透明颅窗，并设对照组。术后第0、2、4、6、8天经颅窗行光学相干断层血管造影(optical coherence tomography angiography, OCTA)成像，第1天行头部MRI检查，第2天行脑组织哌莫硝唑免疫组织化学检测。结果: MRI T2W1和免疫组织化学检测结果均显示创伤脑组织水肿和缺氧深达脑皮质全层，OCTA示TBI组和对照组两组大鼠术后脑皮质表面静脉均显著扩张迂曲，第8天恢复。TBI组有效灌注微血管密度由第0天的39.38%±4.48%最低降至第2天的27.84%±6.01%，显著低于第0、6、8天(P < 0.05)；第8天最高达61.71%±7.69%，显著高于第0、2、4天(P < 0.05)；TBI组有效灌注微血管密度第2天显著低于对照组(P=0.021)，第8天则显著高于对照组(P=0.030)。结论: OCTA可作为TBI大鼠损伤脑皮质有效灌注微血管成像和计量方法，TBI后创伤半暗带内有效灌注微血管密度降低后逐渐恢复，在第8天显著增加。

Objective: To observe the dynamic changes of microvascular injury and repair in the penumbra of traumatic brain injury (TBI) rats with effective cerebral perfusion microvascular imaging using optical coherence tomography angiography (OCTA). Methods: Transparent closed cranial windows were placed in craniotomy rats after TBI caused by weight drop. All the rats in TBI group and control group underwent head MRI examination on the first postoperative day, and the changes of cerebral cortical microvessel density were measured by OCTA through cranial windows on d0, d2, d4, d6, and d8. On the second day after the operation, the same number of rats in the two groups were selected to complete the immunohistochemical staining of brain tissue with pimonidazole, an indicator of hypoxia. Results: MRI T2W1 and immunohistochemical staining demonstrated that edema and hypoxia in the traumatic brain tissue extended deeply throughout the entire cortex. OCTA showed that the cortical surface veins of the rats in both groups were significantly dilated and tortuous after operation, and recovered to the postoperative day level on d8. The effective perfusion microvessel density of the rats in both groups gradually recovered after a temporary decrease, and the TBI group decreased from 39.38%±4.48% on d0 to 27.84%±6.01% on d2, which was significantly lower than that on d0, d6, and d8 (P < 0.05). The highest value was 61.71%±7.69% on d8, which was significantly higher than that on d0, d2, and d4 (P < 0.05). The control group decreased from 44.59%±7.78% on d0 to 36.69%±5.49% on d2, which was significantly lower than that on d0, d6, and d8 (P < 0.05). The highest value was 51.92%±5.96% on d8, which was significantly higher than that on d2, and d4 (P < 0.05). Comparing the two groups, the effective perfusion microvessel density in the TBI group was significantly lower than that in the control group on d2 (P=0.021), and significantly higher than that in the control group on d8 (P=0.030). Conclusion: OCTA can be used as a method of imaging and measurement of effective perfusion microvessels in the injured cerebral cortex of TBI rats. After TBI, the effective perfusion microvessel density in the wound penumbra gradually recovered after decreasing, and increased significantly on d8.