建立油酸型动物模型，研究急性呼吸窘迫综合征（ARDS）胸部弥漫性彗星尾征与腹部脏器早期损伤的相关性。

健康日本大耳白兔21只，雌性，将实验动物分为实验组（11只）与对照组（10只），制模前留取全部实验动物的肺、肝、肾声像图，随即处死对照组实验兔。实验组制备油酸型胸部弥漫性彗星尾征动物模型，制模成功的标准为胸部声像图表现为至少一个肺区出现不同程度的弥漫性彗星尾征。制模成功后留取肺、肝、肾脏超声声像图，处死实验兔。解剖2组实验兔，取出肺、肝、肾、脾脏，制备组织切片。观察、记录2组实验兔各脏器的大体观及镜下组织学改变。根据胸部声像图表现记录超声评分：短小彗星尾征为1分，孤立彗星尾征2分，轻度弥漫性彗星尾征3分，中度弥漫性彗星尾征4分，瀑布征（重度弥漫性彗星尾征）5分。采用两独立样本非参数检验中的曼-惠特尼秩和检验，检验肝脏病理损伤阳性实验兔与阴性实验兔的肺超声评分是否存在显著差异；采用Pearson相关性检验，对肝脏病理损伤阳性组的损伤面积百分比与超声评分进行相关性分析。根据脏器镜下病理损伤面积百分比评估脏器的损伤程度，比较胸部弥漫性彗星尾征与腹部脏器损伤的相关性。

实验组胸部弥漫性彗星尾征制模的成功率为100%，肝、肾声像图表现实验前后未见明显改变。实验组肺脏阳性病理改变的发生率为100%（11只/11只），大体病理表现为肺脏形态饱满，表面暗红色出血区；镜下病理表现为肺水肿（11只/11只，100%）、肺出血（9只/11只，81.8%）。实验组肝脏阳性病理改变的发生率为45.5%（5只/11只），大体病理改变为形态饱满，表面呈红褐色、质韧；镜下病理表现为肝细胞水肿（5只/11只，45.5%）。实验组肾脏阳性病理改变的发生率为18.2%（2只/11只），大体病理未见明显异常，镜下病理可见肾小管上皮细胞水肿（2只/11只，18.2%）。肝脏损伤阳性实验兔的肺超声得分明显高于无肝脏损伤者，差异有统计学意义（Z=-2.529，P=0.011）。肝脏损伤阳性实验兔的肺超声得分与肝脏损伤面积呈正相关（r=0.893，P=0.041），肺超声得分越高，肝脏损伤程度越重。同期脾脏未见明显特异性改变。

胸部弥漫性彗星尾征的出现早于肝脏、肾脏声像图改变；腹部脏器的组织学改变以肝脏最为敏感，其次为肾脏，胸部弥漫性彗星尾征的范围和程度可提示肝脏和肾脏早期损伤。

To study the correlation between multiple comet tail sign and the early abdominal visceral injury and explore the clinical application of the multiple comet tail sign in prompting the early abdominal visceral injury in an oleic acid animal model.

The experimental animals were divided into an experimental group and a control group. The sonograms of the lungs, livers and kidneys of control group were collected, and then the rabbits were executed. The animals of experimental group were made into multiple comet tail sign models. The thorax sonogram of successful model showed at least one lung area with varying degrees of multiple comet tail sign. Collect the sonograms of lungs, livers and kidneys were collected, and then the rabbits were executed. The two groups of rabbits were dissected, and the lungs, livers, kidneys, and spleens were removed to make the tissue sections. The gross pathologic findings and microscopic histological changes of the two groups were observed and noted. The ultrasound scores of chest sonograms were recorded: short comet tail sign for 1 point, isolated comet tail sign for 2 points, mild multiple comet tail sign for 3 points, moderate multiple comet tail sign for 4 points, and falls sign (severe multiple comet tail sign) for 5 points. The degree of organ injury was assessed by the percentage of pathologic injury area under microscope, and the correlation between the multiple comet tail sign and abdominal organ injury was analyzed.

The successful rate of multiple comet tail sign model in experimental group was 100%. The sonograms of liver and kidney have no significant change after the experiment. The incidence of positive pathologic changes in experimental group was 100% (11/11). The gross pathologic findings of lung were complete shape with dark red hemorrhagic area at surface; the microscopic pathologic findings were pulmonary edema (11/11, 100%) and pulmonary hemorrhage (9/11, 81.8%). The incidence of positive pathologic changes in the liver of experimental group was 45.5% (5/11). The gross pathologic findings of liver were complete shape with reddish brown surface and flexible texture; the microscopic pathologic findings were cellular swelling of hepatocytes (5/11, 45.5%). The incidence of positive pathologic changes in the kidneys of experimental group was 18.2% (2/11). The gross pathology had no obvious changes, and the microscopic pathologic findings were cellular swelling of renal tubular epithelial cells (2/11, 18.2%). Results showed that the lung ultrasound scores of rabbits with liver injury were obviously higher than those of rabbits with no liver injury, and there was significant differences (Z=-2.529, P=0.011). There was a statistically significant positive correlation between the lung ultrasound scores of rabbits with liver injury and the microscopic pathologic area of liver lesion (r=0.893, P=0.041), and the higher the lung ultrasound score, the more severity of the liver injury.

The appearance of multiple comet tail sign is earlier than the sonogram changes of liver and kidney. The most sensitive pathologic changes of abdominal organ appear in liver, followed by kidney. The scope and extent of the multiple comet tail sign can prompt the early injury in liver and kidney.