Treatment of traumatic brain injury, within a few minutes and even before transportation to the nearest medical facility, can significantly curtail injury severity and even prevent death. The primary aim of this study was to evaluate the effect of laser irradiation as a therapeutic intervention tool immediately following brain injury. To this end, a dual-wavelength laser speckle contrast imaging (DW-LSCI) system based on two laser sources at two wavelengths 532 and 660 nm was employed to monitor changes in cerebral blood flow, tissue saturation and rate of oxygen consumption in a mouse model of intact head injury. In addition, structural changes of tissue were evaluated using linear approximation to Rayleigh-MIE scattering in the range between the two laser wavelengths. Furthermore, cerebral tissue temperature was imaged by a thermal camera providing additional information on physiological brain tissue condition. Experiments were conducted on anesthetized mice (n = 6, female) subjected to a closed head weight-drop model of focal brain injury. After 5 min of baseline measurement, focal brain injury was induced and measurements were conducted for 10 min. Low-level laser therapy (LLLT) was than administrated for a duration of 15 min with uniform exposure of 45 J/cm² from a CW diode laser source (810 nm). Concurrently, measurements were carried out over the treatment time interval. Laser illumination was then blocked and measurements continued for another 20 min, followed by euthanasia. In comparison to baseline measurements, noticeable variations were revealed post-injury which indicate the severity of brain damage. The use of LLLT inhibited the development of complications in the injured mice by increasing blood flow and saturation and overall oxygen consumption level over the injured area which highlights its effectiveness as a neuroprotective agent immediately following brain injury. Different doses of low-level laser irradiation were also tested (n = 12) with less effectiveness on cerebral parameters. The results presented here support our hypothesis that a high dose of laser irradiation as a first aid can attenuate the injury and save the brain from further worse outcome. To the best of our knowledge, the implementation of the DW-LSCI system to monitor brain hemodynamic and metabolic response to LLLT shortly after head injury in intact mouse brain has not been previously reported.

创伤性脑损伤的治疗，在几分钟内，甚至在运送到最近的医疗机构之前，可以显着降低损伤的严重程度，甚至可以防止死亡。本研究的主要目的是评估激光照射作为脑损伤后立即治疗干预工具的效果。为此，采用基于两个波长 532 和 660 nm 的两个激光源的双波长激光散斑对比度成像 (DW-LSCI) 系统来监测小鼠脑血流量、组织饱和度和耗氧率的变化完整头部损伤模型。此外，在两个激光波长之间的范围内，使用瑞利-MIE 散射的线性近似来评估组织的结构变化。此外，脑组织温度由热像仪成像，提供有关生理脑组织状况的额外信息。实验是在麻醉的小鼠身上进行的（n  = 6，女性）接受局灶性脑损伤的闭合头部减重模型。基线测量 5 分钟后，诱发局灶性脑损伤并进行 10 分钟测量。然后在 45 J/cm ^{2 的}均匀照射下进行低强度激光治疗 (LLLT) 持续 15 分钟来自 CW 二极管激光源 (810 nm)。同时，在治疗时间间隔内进行测量。然后阻断激光照射并继续测量另外 20 分钟，然后进行安乐死。与基线测量相比，受伤后显示出明显的变化，这表明脑损伤的严重程度。LLLT 的使用通过增加受伤区域的血流量和饱和度以及整体耗氧水平来抑制受伤小鼠并发症的发展，这突出了其作为脑损伤后神经保护剂的有效性。还测试了不同剂量的低强度激光照射（n = 12) 对大脑参数的有效性较低。这里呈现的结果支持我们的假设，即高剂量的激光照射作为急救可以减轻伤害并使大脑免于进一步恶化的后果。据我们所知，在完整的小鼠大脑中，在头部受伤后不久，DW-LSCI 系统监测脑血流动力学和对 LLLT 的代谢反应的实施尚未见报道。