CT和MRI动态增强扫描诊断小肝癌的比较研究

Comparison Computer Tomography and Magnetic Resonance Imaging Study of dynamic contrast enhancement in the Diagnosis of Small Hepatocellular Carcinoma

目的比较CT和MRI动态增强扫描对小肝癌(small hepatocellular carcinomas,SHCC)诊断的敏感性和一致性。方法由2名有5年以上腹部诊断经验的影像科医师对所有CT和MRI动态增强扫描图像进行盲审,当观察到肝动脉期病灶明显强化,门静脉延迟期病灶廓清,确诊为典型SHCC,动脉期明显强化,门脉期延迟期病灶不廓清,可疑SHCC,动脉期不强化,不能诊断SHCC。计算CT和MRI动态增强扫描诊断SHCC的敏感性和Cohen’kappa(k)的一致性。结果在27例患者中,包括27个SHCC结节(d<2cm)。CT和(或)MRI动态增强扫描诊断小肝癌的敏感性分别为48%,81%(P=0.01)。CT诊断SHCC的敏感性78%显著高于MRI的敏感性52%(P=0.04)。CT和MRI对27例SHCC结节作出诊断的一致性差(k=0.319,P=0.05)。CT不能确诊的病例,进一步行MRI扫描,能将诊断的敏感性提高3.7%。而MRI不能确诊的病例,进一步行CT扫描,敏感性提高29.6%。结论 CT或MRI任一项影像检查出现典型的强化方式就足以诊断SHCC,但MDCT多期动态扫描比动态MRI具有更高的敏感性。

Objective To compare the sensitivity and agreement between CT and MRI of dynamic contrast enhancement for the diagnosis of small HCCs.Methods All CT and MRI of dynamic contrast enhancement images were blindly reviewed by two experienced abdominal radiologists（more than 5 years）,nodules with hepatic arterial enhancement and washout during the portal/delayed phases were classified as typical SHCC,nodules with only hepatic arterial enhancement without washout during the portal/delayed phases were qualified as suspicious SHCC,nodules with negative arterial enhancement were defined as non-diagnostic SHCC.The sensitivity and Cohen＇s kappa（k）for agreement were calculated.Result In 27 patients,27 HCC nodules（1~2 cm）were included.Diagnosis with a single-imaging modality（CT or MRI）was 81 % versus 48%（P=0.01）.The CT sensitivity was significantly higher than MRI（78% versus 52%,P=0.04）.Among 27 nodules that underwent both CT and MRI,a discordance in typical enhancement patterns was found（k=0.319,P=0.05）.In cases with inconclusive CT results,MRI gave only an additional 3.7 % sensitivity to reach a diagnosis.In contrast,further CT imaging following inconclusive MRI results gave an additional29.6%sensitivity.Conclusions A single typical imaging modality is sufficient to diagnose small HCCs.Compared with MRI,multiphasic CT has a higher sensitivity.