双能CT成像鉴别肾上腺良恶性病变的初步研究

Preliminary study of dual energy CT in differentiation of adrenal lesions

目的:通过对肾上腺病变的CT能谱特征分析,初步探讨双能CT成像在鉴别肾上腺良恶性病变中的价值。方法:在本院行肾上腺CT扫描的患者23例(共24个肾上腺结节),对全部结节的平扫双能CT成像的能谱曲线、单能量的密度测量、水-钙和水-碘基物质定量测量和有效原子序数进行分析。结果:经病理及临床诊断,24例结节中共有良性病变17例、交界性肿瘤4例、恶性病变3例。良性病变的能谱曲线有上升型(3例)、勺子型(4例)和下降型三种;而交界性肿瘤和恶性病变均只有下降型一种(7例)。在不同单能量(40～140keV)图像上,良性结节的密度值最小[(35.5±37.3)～(11.9±13.3)HU],交界性肿瘤最高[(111.4±118.9)～(29.1±11.4)HU],且差异具有统计学意义(P<0.05)。水-钙和水碘基物质测量显示恶性病变的含水量最高分别为(1024.7±8.9)和(1029.9±7.3)mg.ml-1,良性病变量低[分别为(1008.8±10.7)和(1010.3±12.0)mg.ml-1]。而有效原子序数三者之间差异无显著性意义(P>0.05)。结论:肾上腺良恶性病变在双能CT成像上具有不同的特征。应用双能CT成像的多种参数对鉴别良性结节与交界性肿瘤和恶性病变具有很大的潜能。

Objective：To explore the value of dual-energy CT in differentiating benign nodules from malignancies in adrenal glands.Methods：Twenty-three patients with 24 adrenal nodules were recruited in this study.Un-enhanced dual energy CT images were analyzed,including depicting energy spectral curves,measuring CT values under each mono keV,water-calcium concentration,water-iodine concentration and Effective-Z.Results：Among these 24 nodules,17 were diagnosed as benign nodules,4 were pheochromocytomas and 3 were malignancies.The energy spectral curves of benign nodules included ascending type（n=3）,spoon type（n=4） and descending type（n=10）,while descending type curves were shown in all pheochromocytomas（n=4） and malignancies（n=3）.The CT values of benign nodules were much smaller than those of pheochromocytomas and malignancies under each mono keV（P0.05）.Water concentration was the highest in malignancies.There was no significant difference of Effective-Z in different types of adrenal nodules（P0.05）.Conclusion：It is promising to apply dual energy CT with multiple parameters in differentiation of adrenal lesions.