Hollett M D, Jeffrey R B, Nino-Murcia M, Jorgensen M J, Harris D P
Department of Radiology, Stanford University Hospital, CA 94305, USA.
AJR Am J Roentgenol. 1995 Apr;164(4):879-84. doi: 10.2214/ajr.164.4.7726040.
Helical CT scanners now allow sequential arterial phase and portal venous phase scans of the entire liver to be obtained during a single bolus injection of contrast material. The purpose of this study was to determine if arterial phase scans improve detection of small (< or = 1.5 cm) malignant hepatic neoplasms when compared with portal venous scans alone.
Dual-phase helical CT of the liver was done in 96 patients referred for known or suspected malignant hepatic lesions. Malignant hepatic neoplasms were detected in 38 patients (27 with at least one small neoplasm), one patient had undetected metastases, one patient had a benign hepatic neoplasm, and 56 patients had no hepatic neoplasm. Proof of individual neoplasms was based on biopsy results, surgical findings, or findings on other imaging studies (primarily follow-up CT). The absence of disease was established by surgical or autopsy findings, findings on subsequent imaging studies, or a combination of clinical and laboratory data. A total of 150 ml of 60% nonionic contrast material was infused at 5 ml/sec followed by sequential arterial phase and portal venous phase helical scans of the liver. Three radiologists retrospectively reviewed the scans. Individual lesions were measured and the conspicuity of each lesion on arterial phase and portal venous phase scans was compared. The percentage of patients in whom some malignant neoplasms were detected better on the arterial phase scan was calculated using categories based on lesion size and typical tumor vascularity.
In 10 (37%) of 27 patients who had at least one small malignant neoplasm, lesions 1.5 cm or less in diameter were only visible or were more conspicuous on the arterial phase scan. No malignant neoplasms more than 1.5 cm in diameter were visible only on the arterial phase scan. In four (11%) of 38 cases, malignant neoplasms more than 1.5 cm in diameter were more conspicuous on the arterial phase scan. The arterial phase scans improved lesion conspicuity in nine (39%) of 23 patients who had typically hypervascular neoplasms, whereas lesion conspicuity was improved in three (20%) of 15 patients who had typically hypovascular neoplasms (p = .02). The arterial phase scan resulted in the false-positive detection of lesions in two (2%) of 96 cases.
Arterial phase helical CT of the liver improves detection of some small, malignant hepatic neoplasms when performed in addition to portal venous scanning. The value is greatest in those patients who have hypervascular neoplasms.
螺旋CT扫描仪现在允许在单次团注造影剂期间对整个肝脏进行动脉期和门静脉期的连续扫描。本研究的目的是确定与仅进行门静脉扫描相比，动脉期扫描是否能提高对小的（≤1.5 cm）肝脏恶性肿瘤的检测率。
对96例因已知或疑似肝脏恶性病变而转诊的患者进行肝脏双期螺旋CT检查。38例患者检测出肝脏恶性肿瘤（27例至少有一个小肿瘤），1例患者有未被检测到的转移瘤，1例患者有肝脏良性肿瘤，56例患者无肝脏肿瘤。单个肿瘤的确诊依据活检结果、手术发现或其他影像学检查结果（主要是随访CT）。通过手术或尸检结果、后续影像学检查结果或临床与实验室数据的综合判断来确定无疾病。以5 ml/秒的速度注入150 ml 60%的非离子型造影剂，随后对肝脏进行动脉期和门静脉期的连续螺旋扫描。三位放射科医生对扫描结果进行回顾性分析。测量单个病变，并比较每个病变在动脉期和门静脉期扫描中的显影情况。根据病变大小和典型肿瘤血管情况进行分类，计算在动脉期扫描中某些恶性肿瘤检测效果更好的患者百分比。
在27例至少有一个小的恶性肿瘤的患者中，10例（37%）直径1.5 cm或更小的病变仅在动脉期扫描中可见或更明显。直径超过1.5 cm的恶性肿瘤没有仅在动脉期扫描中可见的情况。在38例病例中的4例（11%）中，直径超过1.5 cm的恶性肿瘤在动脉期扫描中更明显。动脉期扫描使23例典型高血供肿瘤患者中的9例（39%）病变显影改善，而15例典型低血供肿瘤患者中的3例（20%）病变显影改善（p = 0.02）。动脉期扫描在96例病例中的2例（2%）导致病变的假阳性检测。
肝脏动脉期螺旋CT在门静脉扫描的基础上进行时，能提高对一些小的肝脏恶性肿瘤的检测率。对高血供肿瘤患者的价值最大。
