Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Er Rd, Shanghai, China 200025.
Radiology. 2011 Jun;259(3):720-9. doi: 10.1148/radiol.11101425. Epub 2011 Feb 25.
To investigate the usefulness of computed tomographic (CT) spectral imaging parameters in differentiating small (≤3 cm) hepatic hemangioma (HH) from small hepatocellular carcinoma (HCC), with or without cirrhosis, during the late arterial phase (AP) and portal venous phase (PVP).
This prospective study was institutional review board approved, and written informed consent was obtained from all patients. The authors examined 49 patients (39 men, 10 women; 65 lesions) with CT spectral imaging during the AP and the PVP. Twenty-one patients had HH; nine, HCC with cirrhosis; and 19, HCC without cirrhosis. Iodine concentrations were derived from iodine-based material-decomposition CT images and normalized to the iodine concentration in the aorta. The difference in iodine concentration between the AP and PVP (ie, iodine concentration difference [ICD]) and the lesion-to-normal parenchyma ratio (LNR) were calculated. Two readers qualitatively assessed lesion types on the basis of conventional CT characteristics. Sensitivity and specificity were compared between the qualitative and quantitative studies. The two-sample t test was performed to compare quantitative parameters between HH and HCC.
Normalized iodine concentrations (NICs) and LNRs in patients with HH differed significantly from those in patients with HCC and cirrhosis and those in patients with HCC without cirrhosis: Mean NICs were 0.47 mg/mL ± 0.24 (standard deviation) versus 0.23 mg/mL ± 0.10 and 0.23 mg/mL ± 0.08, respectively, during the AP and 0.83 mg/mL ± 0.38 versus 0.47 mg/mL ± 0.86 and 0.52 mg/mL ± 0.11, respectively, during the PVP. Mean LNRs were 5.87 ± 3.36 versus 2.56 ± 1.10 and 2.29 ± 0.87, respectively, during the AP and 2.01 ± 1.33 versus 0.96 ± 0.16 and 0.93 ± 0.26, respectively, during the PVP. The mean ICD for the HH group (1.37 mg/mL ± 0.84) was significantly higher than the mean ICDs for the HCC-cirrhosis (0.33 mg/mL ± 0.29) (P < .001) and HCC-no cirrhosis (0.82 mg/mL ± 0.99) (P = .03) groups. The combination of NIC and LNR had higher sensitivity and specificity compared with those of conventional qualitative CT image analysis during individual and combined phases.
Use of spectral CT with fast tube voltage switching may increase the sensitivity for differentiating small hemangiomas from small HCCs in two-phase scanning.
研究在晚期动脉期（AP）和门静脉期（PVP），使用 CT 能谱成像参数鉴别≤3cm 小肝血管瘤（HH）和伴有或不伴有肝硬化的小肝细胞癌（HCC）的有效性。
本前瞻性研究经机构审查委员会批准，并获得所有患者的书面知情同意。作者在 AP 和 PVP 期间对 49 例（39 名男性，10 名女性；65 个病灶）患者进行了 CT 能谱成像检查。21 例患者为 HH；9 例为 HCC 合并肝硬化；19 例为 HCC 不合并肝硬化。从基于碘的物质分解 CT 图像中得出碘浓度，并将其标准化为主动脉中的碘浓度。计算 AP 和 PVP 之间的碘浓度差（即碘浓度差[ICD]）和病变与正常实质的比值（LNR）。两位读者根据常规 CT 特征对病变类型进行定性评估。比较定性和定量研究之间的敏感性和特异性。对 HH 和 HCC 之间的定量参数进行两样本 t 检验。
HH 患者的标准化碘浓度（NICs）和 LNR 与 HCC 合并肝硬化患者、HCC 不合并肝硬化患者之间存在显著差异：AP 时，HH 患者的平均 NIC 分别为 0.47mg/mL±0.24（标准差）、0.23mg/mL±0.10 和 0.23mg/mL±0.08，而 HCC 合并肝硬化患者和 HCC 不合并肝硬化患者分别为 0.23mg/mL±0.08、0.47mg/mL±0.08 和 0.52mg/mL±0.11；HH 患者的平均 LNR 分别为 5.87±3.36、2.56±1.10 和 2.29±0.87，而 HCC 合并肝硬化患者和 HCC 不合并肝硬化患者分别为 2.01±1.33、0.96±0.16 和 0.93±0.26；HH 组的平均 ICD（1.37mg/mL±0.84）显著高于 HCC 合并肝硬化组（0.33mg/mL±0.29）（P＜0.001）和 HCC 不合并肝硬化组（0.82mg/mL±0.99）（P=0.03）。与传统定性 CT 图像分析相比，NIC 和 LNR 的联合应用在各期及联合期的敏感性和特异性均较高。
使用具有快速管电压切换的能谱 CT 可能会提高在两期扫描中鉴别小血管瘤和小 HCC 的敏感性。
