肝细胞癌螺旋CT三期扫描的不典型表现

Atypical manifestation of hepatocellular carcinoma by triple-phase spiral CT scan

目的 探讨肝细胞癌 (HCC)在螺旋CT三期扫描中的不典型表现 ,并分析其产生原因。方法 75例HCC患者平扫后行螺旋CT三期增强扫描 ,注射对比剂后分别于 2 5～ 30s和 6 5～ 70s行动脉期和门静脉期扫描 ,3～ 5min行延迟期扫描 ,分析病灶的增强特点。结果 75例共发现 92个病灶。 6 0个病灶有典型增强表现 ,即动脉期呈高密度 (均匀或不均匀 ) ,门静脉期迅速变成低密度 ,延迟期仍呈低密度。 32个病灶为不典型表现 ,其中 14个病灶动脉期呈高密度 ,门静脉期呈等密度 ,延迟期扫描有 10个呈低密度 ,4个仍呈等密度 ;8个病灶在动脉期和门静脉期均呈高密度 ,延迟期有 3个呈等密度 ,5个呈低密度 ;6个病灶动脉期呈等密度 ,门静脉期和延迟期呈低密度 ;4个病灶在动脉期、门静脉期和延迟期中均呈低密度。结论 HCC在螺旋CT三期扫描中有多种不典型表现 ,病变的血供情况、扫描技术和肝脏生理、病理状态等是产生不典型表现的常见原因。

Objective To analyze the cause of atypical manifestation of hepatocellular carcinoma (HCC) in triple-phase spiral CT enhanced scan. Methods Triple-phase spiral CT scan was performed in 75 patients with HCC. The hepatic arterial phase (HAP), portal venous phase (PVP) and delayed phase (DP) images were started at 25～30 s, 65～70 s and 3～5 min after injection of contrast medium. The contrast enhanced patterns of lesion were observed and analyzed. Results Ninety-two lesions were found in 75 patients. Typical enhanced findings such as hyperdense in HAP and hypodense in PVP and DP was found in 60 of 92 lesions. Atypical enhanced findings were observed in the other 32 lesions. Fourteen of 32 atypical enhanced lesions were hyperdense in HAP and isodense in PVP, of which 8 were seen in liver cirrhosis and 3 in fatty liver. In DP, 10 were hypodense and 4 still isodense. Eight of the 32 lesions were hyperdense both in HAP and PVP, of which 6 were seen in fatty liver. In DP, 3 were isodense and 5 were hypodense. Six of 32 lesions were isodense in HAP which became hypodense in PVP and DP. Four of 32 lesions were all hypodense in HAP, PVP and DP. Conclusion Multiple atypical enhanced manifestations are present by triple-phase spiral CT scan in HCC. Pattern of blood supply, scanning technique and pathophysiologic status are usually the cause of these findings.