超声、超声造影及多层螺旋CT对小肝癌的影像学诊断

Imaging diagnosis of small hepatocellular carcinoma using ultrasound, contrast-enhanced ultrasound and multislice spiral CT

目的探讨二维灰阶超声、超声造影及多层螺旋CT对小肝癌影像学早期诊断和鉴别诊断的价值。方法对用二维灰阶超声发现35例肝脏占位性病变的患者进行超声造影,记录并分析35例病例的动脉期、门静脉期、延迟期三个时期不同图像的造影增强前后的动态血流改变特征。再采用多层螺旋扫描模式,三期动态增强扫描方案通过工作站AW4.2系统,对病灶行多平面重建及容积成像。最后通过病理确诊。结果超声、超声造影和多层螺旋CT对小肝癌诊断的敏感性为77.8%、94.4%、100%,特异性为88.2%、100%、94.1%,阳性预示值为87.5%、100%、94.7%,阴性预示值为78.9%、94.4%、100%,与病理诊断一致性为82.9%、97.1%、97.1%,约登指数为0.66、0.94、0.94。结论超声造影和多层螺旋CT对小肝癌的诊断效能显著高于二维灰阶超声,对小肝癌早期诊断和鉴别诊断均具有较高的临床应用价值。但对于某些非典型特殊病例还需3种方法进行联合诊断,发挥各自不同的优势。

Objective To evaluate the value of gray-scale ultrasound, contrast-enhanced ultrasound and multislice spiral CT in early and differential imaging diagnosis of small hepatocellular carcinoma （SHCC）. Methods This study included 35 patients with space-occupying lesions in the liver identified by routine ultrasound examination. The hemodynamics of the patients was recorded during the arterial, portal and lag phases using contrast-enhanced ultrasound. The enhancement features of the 3 phases were observed using multislice spiral CT. All the cases were confirmed by pathological examinations. Results For SHCC diagnosis, gray-scale ultrasound, contrast-enhanced ultrasound and mutislice spiral CT showed a sensitivity of 77.8%, 94.4%, and 100%, specificity of 88.2%, 100%, and 94.1%, positive predictive value of 87.5%, 100%, and 94.7%, negative predictive values 78.9%, 94.4%, and 100%, concordance rate of 82.9%, 97.1%, and 97.1% and Younden index of 0.66, 0.94, and 0.94, respectively. Conclusion Contrast-enhanced ultrasound and multislice spiral CT have significantly greater diagnostic efficacy than gray-scale ultrasound in early and differential diagnosis of SHCC. But in some atypical cases, gray-scale ultrasound, contrast-enhanced ultrasound and multislice CT have to be combined to establish a diagnosis.