Abstract：
Cerebrovascular dysfunction following mild traumatic brain injury (mTBI) is understudied relative to other microstructural injuries, especially during neurodevelopment. The blood-oxygen level dependent response was used to investigate cerebrovascular reactivity (CVR) in response to hypercapnia following pediatric mTBI (pmTBI; ages 8-18 years), as well as pseudocontinuous arterial spin labeling to measure cerebral blood flow (CBF). Data were collected ∼1-week (N = 107) and 4 months (N = 73) post-injury. Sex- and age-matched healthy controls (HC) underwent identical examinations at comparable time points (N = 110 and N = 91). Subtle clinical and cognitive deficits existed at ∼1 week that resolved for some, but not all domains at 4 months post-injury. At both visits, pmTBI showed an increased maximal fit between end-tidal CO2 regressor and the cerebrovascular response across multiple regions (primarily fronto-temporal), as well as increased latency to maximal fit in independent regions (primarily posterior). Hypoperfusion was also noted within the bilateral cerebellum. A biphasic relationship existed between CVR amplitude and age (i.e., positive until 14.5 years, negative thereafter) in both gray and white matter, but these neurodevelopment effects did not moderate injury effects. CVR metrics were not associated with post-concussive symptoms or cognitive deficits. In conclusion, cerebrovascular dysfunction may persist for up to four months following pmTBI.
摘要：
相对于其他微观结构损伤，轻度创伤性脑损伤（mTBI）后的脑血管功能障碍研究不足。尤其是在神经发育过程中。使用血氧水平依赖性反应来研究小儿mTBI（pmTBI；年龄8-18岁）后对高碳酸血症的反应性（CVR），以及伪连续动脉自旋标记来测量脑血流量（CBF）。数据收集至伤后1周(N=107)和4个月(N=73)。性别和年龄匹配的健康对照（HC）在可比时间点（N=110和N=91）进行了相同的检查。微妙的临床和认知缺陷在1周时存在，对一些人来说，但不是所有领域在受伤后4个月。在两次访问中，pmTBI显示呼气末CO2回归量与多个区域（主要是前颞叶）的脑血管反应之间的最大拟合度增加，以及在独立区域（主要是后部）达到最大拟合的潜伏期增加。双侧小脑内也注意到灌注不足。CVR振幅和年龄之间存在双相关系(即，阳性直到14.5年，此后为阴性)在灰质和白质中，但这些神经发育效应并没有缓解损伤效应。CVR指标与脑震荡后症状或认知障碍无关。总之,pmTBI后脑血管功能障碍可能持续长达四个月.
