孤立性肺结节CT动态增强扫描的层面优化及临床应用  

A primary study of slice optimization of dynamic contrast-enhanced CT scan and its practical application on solitary pulmonary nodules

作　　者：罗良平[1] 蔡春仙[2] 吴何嘉[1] 陈金城[1] 

机构地区：[1]暨南大学附属第一医院医学影像中心,广州510630 [2]四川省内江市第一人民医院

出　　处：《中华放射学杂志》2006年第12期1286-1291,共6页Chinese Journal of Radiology

基　　金：中国博士后科学基金资助项目(2003033414);广东省自然科学基金资助项目(5006074)

摘　　要：目的利用选层重组的方法改善孤立性肺结节(SPN)CT动态增强扫描各延时像测量层面的一致性,并探讨其临床应用价值。方法(1)对3种均质液体行CT螺旋扫描并在Z轴方向同层厚任意多平面重组,比较其原始扫描图像及重组图像密度测量值的差异。(2)对72例SPN患者行螺旋CT动态增强扫描,运用一定的选层重组的方法保证各延时像测量层面的一致性。并对其中46例经病理及临床证实的SPN的CT动态增强特点进行评价,评估其增强前后的CT值、强化峰值、SPN与主动脉的强化值比。结果(1)不同密度的均质液体同层厚的原始扫描图像及重组图像间密度测量值差异无统计学意义(F=1.544,P>0.05);(2)67例SPN选层重组前、后各延时像测量层面一致率分别为20.98%(14/67)和97.01%(65/67),其差异有统计学意义(χ2=80.22,P=0.00)。多层螺旋CT对5例SPN的选层重组全部成功。(3)SPN的CT动态增强各延时像测量层面一致性优化以后,恶性结节与炎性结节强化峰值[(38.48±14.32)、(42.48±11.55)HU]和结节与主动脉强化值比[(19.64±9.52)、(21.14±7.77)%]均明显高于良性结节[(9.52±3.78)HU、(3.41±1.86)%];P值均<0.01。炎性结节的强化峰值、结节与主动脉强化值比[(42.48±11.55)HU、(21.14±7.77)%]与恶性结节[(38.48±14.32)HU、(19.64±9.52)%]间的差异无统计学意义(P值均>0.05)。CT动态增强选层重组保证各延时像测量层面一致性后,使其对SPN定性的准确率由78%提升至80%。结论螺旋CT扫描Z轴方向同层厚任意重组对均质物质的密度值的测量无明显影响。CT动态增强扫描各延时像测量层面一致性的优化可进一步客观反映SPN的动态增强情况,有利于其形态学的比较及CT值的测量,有望提高其对孤立性肺结节鉴别诊断的能力。Objective To improve the slice concordance in measurement of delayed images by using image selection and reconstruction in dynamic helical CT, and to evaluate its practical diagnostic application on solitary pulmonary nodule （SPN）. Methods （ 1 ） Three kinds of homogeneous liquid were scanned by helical CT. The difference of CT attenuations between primitive images and the reconstructive images with the same slice thickness was assessed. （2） Seventy-two patients with SPN were studied with dynamic helical CT scan, and the method of image selection and reconstruction was used to improve the slice concordance in measurement of delayed images respectively. Forty-six cases of SPN with pathological and （or） clinical results were studied with dynamic helical CT scan. Pre-and post-contrast attenuation, peak height of time-attenuation curve, and ratio of peak height of the SPN to that of the large artery were evaluated. Results （ 1 ） No significant difference was found between the attenuation of the primitive images and that of the reconstructive images of the homogeneous liquid in different density （ F = 1. 544, P 〉 0. 05 ）. （2） In 67 cases with pre-and post-image selection and reconstruction in single-slice or twin-slice helical CT, the slice concordance rate in measurement was 20. 98% and 97.01% , respectively （ χ^2 = 80. 22, P = 0. 00）. The slice concordance was all accomplished with the same method in multi-slice helical CT in 5 cases. （3） Peak heights and SPN-to-aorta ratios of malignant [ （38.48 ± 14. 32） HU, （ 19.64±9. 52） % ] and inflammatory SPN [ （42. 48± 11.55 ） HU, （21.14± 7.77） % ] were significantly higher than that of benign SPN [ （9. 52±3.78） HU, （3.41±1.86 ） %, P 〈 0. 01 ]. No significant statistical difference was found in the peak height and SPN-to-aorta ratio between malignant and inflammatory SPN （P 〉 0.05）. Slice optimization of dynamic contrast-enhanced CT scan improved the diagnostic accuracy of SPN from 78% to 80%. Conclu

关 键 词：硬币病变 肺 体层摄影术 X线计算机 图像处理 计算机辅助 

分 类 号：R816.4[医药卫生—放射医学]