CAJ | 학술논문

目的探讨新双源CT双能虚拟平扫技术在孤立性肺结节(SPN)评估中替代常规真实平扫的可行性及临床价值.方法对经病理证实的47例SPN患者行双能平扫和增强扫描.双能增强扫描图像经双能软件处理后,生成虚拟平扫图和碘分布图.使用配对t检验比较虚拟平扫图和真实平扫图CT值、噪声、信噪比、SPN直径；以真实平扫为标准,评估虚拟平扫图的图像质量分值、钙化显示,并以CT值强化值≥20 HU判定为恶性结节,评价诊断正确率；使用独立t检验比较增强强化值、碘图CT值和患者单期真实平扫和双能扫描辐射剂量.结果 47个SPN真实平扫图像和虚拟平扫图像平均CT值分别为(29.90±12.43)、(27.52±16.67) HU,差异无统计学意义(t=1.556,P＞0.05)；噪声分别为9.60±3.74、9.88±2.90,差异无统计学意义(t=-0.357,P＞0.05)；信噪比分别为3.07±1.93、2.76±2.36,差异无统计学意义(t=0.767,P＞0.05).以真实平扫和虚拟平扫为基线的SPN平均增强强化值分别为(18.63±8.03)、(20.45±9.13) HU,碘图CT值为(23.82±9.20) HU,真实平扫与碘图差异有统计学意义(t=-2.371,P＜0.05).虚拟平扫图像质量平均(2.71±0.42)分,略低于真实平扫(3分).以真实平扫为标准,虚拟平扫钙化显示率为92.3％(72/78);以强化值≥20 HU判定为恶性结节,碘图CT诊断良恶性的敏感度和正确度最高,分别为82.3％(28/34)、74.5％(35/47)；以虚拟平扫为基线的增强强化值诊断良恶性的特异度最高,为76.9％(10/13).单次CT常规单能平扫和双能扫描患者接受辐射的有效剂量分别为(5.68±1.31)、(4.89±1.27) mSv,差异无统计学意义(t=1.27,P＞0.05).结论双能CT虚拟平扫技术得到的图像质量完全能满足诊断学要求,可以代替以往动态增强扫描中作为基线的常规平扫,进而降低患者的CT检查剂量.
목적 탐토신쌍원CT쌍능허의평소기술재고립성폐결절(SPN)평고중체대상규진실평소적가행성급림상개치.방법 대경병리증실적47례SPN환자행쌍능평소화증강소묘.쌍능증강소묘도상경쌍능연건처리후,생성허의평소도화전분포도.사용배대t검험비교허의평소도화진실평소도CT치、조성、신조비、SPN직경；이진실평소위표준,평고허의평소도적도상질량분치、개화현시,병이CT치강화치≥20 HU판정위악성결절,평개진단정학솔；사용독립t검험비교증강강화치、전도CT치화환자단기진실평소화쌍능소묘복사제량.결과 47개SPN진실평소도상화허의평소도상평균CT치분별위(29.90±12.43)、(27.52±16.67) HU,차이무통계학의의(t=1.556,P＞0.05)；조성분별위9.60±3.74、9.88±2.90,차이무통계학의의(t=-0.357,P＞0.05)；신조비분별위3.07±1.93、2.76±2.36,차이무통계학의의(t=0.767,P＞0.05).이진실평소화허의평소위기선적SPN평균증강강화치분별위(18.63±8.03)、(20.45±9.13) HU,전도CT치위(23.82±9.20) HU,진실평소여전도차이유통계학의의(t=-2.371,P＜0.05).허의평소도상질량평균(2.71±0.42)분,략저우진실평소(3분).이진실평소위표준,허의평소개화현시솔위92.3％(72/78);이강화치≥20 HU판정위악성결절,전도CT진단량악성적민감도화정학도최고,분별위82.3％(28/34)、74.5％(35/47)；이허의평소위기선적증강강화치진단량악성적특이도최고,위76.9％(10/13).단차CT상규단능평소화쌍능소묘환자접수복사적유효제량분별위(5.68±1.31)、(4.89±1.27) mSv,차이무통계학의의(t=1.27,P＞0.05).결론 쌍능CT허의평소기술득도적도상질량완전능만족진단학요구,가이대체이왕동태증강소묘중작위기선적상규평소,진이강저환자적CT검사제량.
Objective To compare the conventional non-enhanced and virtual non-enhanced images of dual-energy computed tomography (CT) in evaluating solitary pulmonary nodules (SPNs).Methods Forty-seven patients with SPNs proved by pathology underwent conventional and enhanced thoracic DECT.The virtual non-enhanced CT images and iodine images were reconstructed based on the enhanced imaging data.The mean CT number,noise,signal to noise (SNR),nodual diameter of SPNs were compared between the true non-contrast CT(TNCT) and the virtual non-contrast CT (VNCT),with paired t test.The image quality and detectability of calcification were also compared.The diagnostic accuracy for malignant nodulesbased on the increased CT values and iodine-enhanced image were compared.The independent t test was used to compare the increased CT number of SPNs and iodine images.The single-phase radioation dose of the single energy,was compared with dual energy scan.Results No significant difference in the mean CT Number(t =1.556,P ＞ 0.05),noise (t =-0.357,P ＞ 0.05),SNR (t =0.767,P ＞ 0.05) on TNCT and VNCT.The mean CT Number,the noise,and SNR were (29.90 ± 12.43)vs (27.52 ± 16.67) HU,(9.60 ±3.74) vs (9.88 ± 2.90),and (3.07 ± 1.93) vs (2.76 ± 2.36),respectively.The increased CT number ofSPNs with TNCT and VNCT from baseline were(18.63 ± 8.03) and(20.45 ± 9.13) HU.The CT number of iodine image was(23.82 ± 9.20)HU.A significant difference was observed between the TNCT and iodineed image (t =-2.371,P ＜ 0.05).The quality scores of VNCT image wasslightly worse than TNCT image.The detectability rate of calcification on VNCT was 92.3％ (72/78).The iodine image carried the highest diagnostic sensitivity rate and accuracy rate,82.3％ (28/34)and 74.5％ (35/47),respectively.The highest specificity rate was 76.9％ (10/13) from the increased CT number with VNCT.No significant difference in single-phase radiation dose was observed between TNCT and VNCT,(5.68 ± 1.31) vs.(4.89 ± 1.27)mSv.Conclusions VNCT could be obtained with similar image quality as TNCT.This methods might favor a reduction in radiation exposure.