16层螺旋CT多期扫描对原发性肝癌的诊断价值

目的通过多层螺旋CT（MSCT）行肝脏多期增强扫描，探讨原发性肝癌（PHC）在多期增强扫描中的强化表现，比较各期的检出率。将动脉早、中及晚期相互组合，优化出诊断PHC的最佳扫捕方案。方法回顾性分析明确诊断为PHC的患者92例，共140个PHC病灶；其中男75例，女17例，年龄28～77岁。采用飞利浦螺旋Brilliancel6扫描机行增强后多期扫描，增强扫描采用3～4期（动脉早期、中期、晚期及门静脉期），动脉早期为22s，动脉中期为29s，动脉晚期为37s，门脉期为75s，延迟期为5min，每个全肝扫描周期为8．2s；扫描结束后在工作站对图像进行处理，统计各期的病灶检出数，并对肝脏与肿瘤实性部分的CT密度值分别进行测量并计算其差值行统计学分析。将动脉早、中、晚期组合成4种方案，计算其各自对病灶的检出率。结果本组140个病灶中，瘤径在增强后的动脉早期、动脉中期、动脉晚期及门静脉期，肿瘤与肝脏密度差值各期间差异有显著性差异（H=55．268，P=0．000〈0．01）。动脉早期检出率最低为35．71％，动脉晚期检出率最高为78．57％，动脉早、中、晚期及门静脉期对于病灶的检出率存在显著性差异（χ^2=33．985，P=0．000）；动脉早期＋晚期（80．00％）与多动脉期（80．00％）联合扫描的检出率一致且最高，同时与单纯动脉早、中或晚期扫捕相比，动脉早期＋晚期扫描及多动脉期联合扫描的检出率最高。结论采用MSCT行肝脏多期增强扫描，优化了动脉期的扫描方案，将全肝扫描落在真正的动脉期内，使显示富血供肿瘤强化的机会增加，同时较薄层面的扫捕也提高了PHC病灶检出的机会。

Effectiveness of 16-Slice CT Multi-Phase Scanning in Diagnosis of PHC

Objective Multi-phase contrast-enhanced MSCT （Multi-Slice Spiral Computerized Tomography） scanning of livers was performed in PHC （Primary Hepatic Cancer） patients to explore the enhancement features of multi-phase scanning in diagnosis of PHC and compare the detection rate in different phases. Combination of the early, middle and late arterial phases was made so as to optimize the scanning solutions for the diagnogis of PHC. Methods Retrospective analysis of 92 confirmed PHC patients （Male： 75; Female： 17; ages ranging from 28 to 77） was made. A total of 140 PHC lesions were found. Contrast-enhanced scanning was performed with Philips spiral Brilliance 16 scanner, using 3-4 phase （early, middle, late arterial and portal venous phase） with the early arterial phase lasting 22 s, middle arterial phase 29 s, late arterial phase 37 s, portal vein phase 75 s, delay time 5 min and a full liver scanning cycle 8.2 s. Then, the imaging data was processed in the workstation, acquiring the statistics concerning the number of lesions detected in different phases and making statistical analysis of the differences in CT density values between the solid portion of livers and tumors. Moreover, through combination of the early, middle and late arterial phases into 4 solutions, the detection rates in different phases were calculated. Results Among 140 lesions that were involved in this study, significant difference existed in density of the tumor and liver in different scanning phases （H=55.268, P =0.000 〈0.0l）. The detection rate in the early arterial phase was 35.71%, ranking the lowest versus the highest one of 78.57% in the late arterial phase among 4 scanning phases; there was significant difference in the detection rates between the early, middle, late arterial and portal venous phases （χ^2=33.985, P=0.000）. Scanning in the early and late arterial phases （80.00%） showed the greatest consistency in the detection rate with the multi-phase scanning （80.00%）. In comparison with the single early, middle or late arterial phase, the combined scanning in the early, late arterial phases and multiple phases had the highest detection rate. Gonclusion Multi-phase contrast-enhanced MSCT scanning of livers optimized the scanning solutions and allowed the whole liver scanning accomplished in the arterial phases, which made it more likely to display tumors with rich blood supplies and detect the PHC lesions in comparison with scanning of the thin-level areas.