兔乳腺肿瘤及炎性病变前哨淋巴结间接CT淋巴造影实验研究

The Experimental Study on Indirect CT Lymphography in Localizing and Evaluating the Sentinel Lymphnodes of Rabbits' Breast Cancer and Inflammation

目的探讨间接CT淋巴造影(CTLG)定位和评价兔乳腺肿瘤及炎性病变前哨淋巴结(SLN)的可行性。方法成年雌兔36只,随机等分为3组,1组于右侧第2乳腺接种VX2肿瘤,1组于右侧第2乳腺注射鸡蛋黄乳胶,最后1组做空白对照。成模后,于每兔右侧第2乳腺注射碘普罗胺(370 mg/mL)1 mL并按摩30 s,分别于注射前及之后1、15、30、45、60 min进行CT扫描。其后,以亚甲蓝按相同方法注射,按摩30 s后解剖同侧腋窝,寻找蓝染淋巴结并进行病理检查。结果所有动物右侧腋窝SLN明显强化,1 min时CT值达最高,为(106.24±28.26)Hu,其输入淋巴管全部显影。非SLN轻度强化,1 min时CT值为(59.43±11.62)Hu,输入淋巴管部分显影。形态上,肿瘤转移SLN明显增大,并可见对比剂充盈缺损;炎性反应性增生SLN体积增大,但对比剂充盈良好;正常SLN较小,对比剂充盈亦良好。采集1 min数据进行3D重建,可很好观察SLN形态及与其它结构关系。在MIP影像上测量SLN长、短径分别为:肿瘤组(10.33±2.63)mm、(7.50±1.82)mm;炎症组(8.09±1.64)mm、(4.72±0.53)mm;对照组(6.38±1.61)mm、(3.31±1.10)mm。统计学分析显示,肿瘤组SLN长、短径均显著大于对照组(P<0.05);炎症组SLN与对照组比较,长、短径亦均显著大于后者(P<0.05);肿瘤组SLN与炎症组相比,长、短径均显著大于后者(P<0.05)。在CTLG过程中,邻近胸壁肌未见强化,邻近小静脉轻度强化。CTLG与亚甲蓝染色对比,SLN显示情况一致。结论 CTLG对于定位兔乳腺肿瘤及炎性病变所致的肿大SLN具有可行性,且根据淋巴结内是否存在对比剂充盈缺损及长、短径的改变有助于评价淋巴结的良、恶性质。

Objective To study the feasibility of indirect CT lymphography （CTLG） in localizing the sentinel lymphnedes （SLNs） of rabbits＇ breast and to evaluate the ability on CTLG in discriminating benign and malignant disease of lymphnedes. Methods 36 adult female rabbits were divided to 3 groups evenly and randomly. The VX2 tumor was transplanted into the fight and second breast in the first group. The yolk colloid was injected in the right and second breast in the second group. The third group was taken as the normal control. After the animal modes was made, inject the Ultravist solution （370 mg I/mL） 1 mL in right and second breast and massage it 30 s in every rabbits. CT scanning was performed before and at 1, 15, 30, 45 and 60 rain after contrast media injection. And then, Methylene Blue, with the same method and same dosage, was injected into the same place. Dissect the right armpit after massaging 30 s. Search blue lymphnedes and take them to the pathological examination. Results The excellent enhancement of all of the SLNs in right armpit was demonstrated. The peak enhancement was obtained lmin after injection. The peak value was （ 106.24±28.26） Hu. All of the afferent lymphatics of SLNs were visualized. The non-SLNs got the slight enhancement. The peak value was （59. 43±11.62） Hu. A part of the afferent lymphatics of non-SLNs were visualized. The volume of the metastatic SLNs was larger than normal SLNs. And there was the phenomenon of filling defect of contrast media in them. The volume of the inflammatory SLNs was larger than normal SLNs too. There was not the phenomenon of filling defect of contrast media in them. The volume of the normal SLNs was small, and there was not the phenomenon of filling defect of contrast media in them. The 3D imaging was rebuilt with the CT scanning datus when lmin after injection. It was demonstrated clearly that the shape of SLNs and the relation with other structures in 3D im-aging. In MIP imaging, the max-diameter and the rain-diameter of the SLNs were： （10.33±2.63） and （7.50±1.82） mm （metastatic）, （8.09±1.64） and （4. 72±0. 53） mm （inflammatoy） ; （6. 38±1.61） and （3.31±1.10） mm （normal）. Statistics： there was noticeable difference between tumor group SLNs and normal group SLNs in the long-diameter and short-diameter （ tumor group 〉 normal group, P〈0. 05 ）, there was noticeable difference between ivflAmmation group SLNs and normal group SLNs in the long-diameter and short-diameter （ inflammation group 〉normal group, P〈0. 05 ）, there was noticeable difference between tttmor group SLNs and inflammation group SLNs in the long-diameter and short-diameter （tumor group〉inflammation group, P〈0. 05）. The adjacent muscle of chest wall was not enhanced and the adjacent vein was enhanced slightly in CTLG. The number of visualized SLNs was the same as the blue dyeing. Conclusions CTLG is useful in localizing SLNs and their afferent lymphatics of rabbits＇ brebist as well as evaluating the pathologic character of SLNs of rabbits＇ breast.