犬颅脑枪弹伤后脑实质致伤区超声显像研究

Ultrasonographic features of brain after gunshot injury of brain in dog

目的探讨犬颅脑枪弹伤致伤区的超声显像特点。方法取成都本地健康成年杂种犬18只,随机分为实验组(12只)和对照组(6只)。麻醉后用53式滑膛枪以左额部为弹着点自左向右冠状向致伤制作犬颅脑低速枪弹伤模型。致伤后去除颅骨瓣,经骨窗应用二维及彩色多普勒超声分别在伤后即刻及1、3、6h观察脑实质内致伤区的成像特点。对照组不予致伤,其余处理同实验组。结果实验组致伤后0.5h内死亡2只,10只纳入观察。对照组脑实质内主要解剖结构正常,实验组脑实质可观察到显著的致伤区特征:①高分辨率二维超声显示脑实质致伤区表现为内径不一、回声显著增强的近似管状回声,并可见斑片状强回声后方伴声影;彩色多普勒超声显示致伤区内未见血流信号,不同时相超声表现未见明显变化,盲管伤伤道较贯通伤复杂;②致伤区周围及远隔部位脑组织仍以低回声为主,图像分析显示致伤区与周边脑组织易于区别。结论超声显像可清楚地显示颅脑枪弹伤脑实质内致伤区或其中伤道的分布和走行,对于颅脑枪弹伤的诊治有重要意义。

Objective To explore the ultrasonic feature of gunshot craniocerebral wound in dog. Methods Eighteen adult mongrels collected from Chengdu territory were randomly divided into experimental group （12 dogs） and control group （6 dogs）. After anesthesia, the dogs in experimental group were shot with a 53 style musket in the frontal region from left to right to establish an animal model of craniocerebral gunshot wound. Then the parietal bone fragments were removed within 30min, and two-dimensional and color Doppler ultrasound was used in the subsequent examinations of brain tissue through the cranial window immediately after the craniotomy, and 1, 3 and 6 hours after injury. Animals in both control and experimental group received the same treatment with exception of gunshot injury. Results Two dogs in experimental group died of gunshot wound within 30min after injury, the remainders survived up to the end of the experiment. Ultrasound image indicated that the main anatomic structure of the dogs in control group was normal, and some distinguished features of wound tract were detected in brain tissue of experimental group. High-resolution ultrasound showed that the the size of the wound tracts varied, and they presented a hyperechoic feature different distinctly from that of normal brain parenchyrna. No flow signals in injured area, and no significant time-dependent changes were detected by color Doppler. The hypoechoic structures were still detected in the brain parenchyma adjacent to the wound tract and brain tissue distant from the wound tract. Image analysis showed that these areas were easy to distinguish from the injured area. Conclusions The results indicate that high-resolution ultrasound may clearly show the tract of cerebral gunshot wound,therefore it has important value in diagnosis and treatment of craniocerebral gunshot wound.