1、对纵隔囊肿 CT 假性强化影响因素的探讨朱振华1，赵莲子2，赵霞3，李秉营3，李海文1，杨光杰41 山东国欣颐养集团淄博医院影像科山东淄博255102;2 复旦大学附属肿瘤医院放射治疗中心上海200032;3 山东中医药大学附属医院放射科山东济南250014;4 青岛大学附属医院 PET/CT 中心山东青岛266000【摘要】目的对 CT 增强扫描中纵隔囊肿假性强化的影响因素进行探讨。方法选取 39 例经手术病理证实的纵隔囊肿患者，对所有患者 CT 平扫以及增强扫描动脉期图像进行数据测量。比较病灶平扫与增强动脉期 CT 值;根据强化后病灶 CT 值上升是否超过 10 HU 分为“低假性强化组”
2、(A 组)、“高假性强化组”(B 组)两组，A 组 16 例，B 组 23 例。对两组患者病灶参数(平扫 CT 值、截面积)、距病灶最近纵隔血管或心腔参数(强化程度、面积、与病灶的距离)、病灶周围增强程度最高的血管参数(强化程度、面积、与病灶的距离)、病灶周围所有大血管或心腔总体参数(总面积、平均增强程度、与病灶的平均距离)进行分析比较。结果平扫与增强扫描所有病灶的 CT 值分别为(12 6 15 0)HU、(26 3 14.9)HU，差异具有统计学意义(P 0 05)。A 组与 B 组病灶平扫 CT 值分别为(19 1 12 5)HU、(8 1 15 2)HU，病灶截面积分别为(5 1 4
3、0)cm2、(3 0 1 9)cm2，最近血管或心腔与病灶的距离分别为(2 9 0 8)cm、(2 3 0 6)cm，病灶周围所有血管或心腔与病灶之间总距离的平均值分别为(5 0 1 2)cm、(3 9 1 5)cm，两组间以上四项参数差异均有统计学意义(P 0 05)。增强后最近血管或心腔与病灶距离可以独立影响病灶的假性强化现象(P 0 05)。结论纵隔囊肿在增强扫描中存在假性强化现象，其主要影响因素有病灶平扫 CT 值、病灶截面积、最近血管或心腔与病灶的距离、病灶周围所有血管或心腔与病灶之间总距离的平均值等，其中距病灶最近血管或心腔与病灶的距离可以对假性强化现象产生独立影响。【关键词】纵隔
4、囊肿;体层摄影术，X 线计算机;假性强化中图分类号:734 5;814 42文献标识码:A文章编号:1006-9011(2023)04-0572-05Preliminary study of pseudo-enhancement of mediastinal cystZHU Zhenhua1，ZHAO Lianzi2，ZHAO Xia3，LI Bingying3，LI Haiwen1，YANG Guangjie41 Department of adiology，Zibo Hospital of Shandong Guoxin Healthcre Group，Shandong Province，
5、Zibo 255102，China2 Department of adiation Oncology，Fudan University Shanghai Cancer Center，Shanghai 200032，China3 Department of adiology，Affliated Hospital of Shandong University of Chinese Medicine，Jinan 250014，China4 PET/CT Center，The Affliated Hospital of Shandong University，Qingdao 266000，China【
6、Abstract】ObjectiveTo find out the influencing factors of pseudo-enhancement of mediastinal cyst in contrast enhanced CTscan MethodsThirty-nine patients with cyst in mediastinum confirmed by pathology were studied retrospectively Parameterswere collected with non-contrast CT scan and arterial phase o
7、f contrast-enhanced CT scan CT values of the cysts in all patientswere compared between contrast-enhanced and non-contrast images According to whether the CT values of the cysts increasedmore than 10 HU or not after enhancement，the patients were divided into two groups:low pseudo-enhancement group(g
8、roup A)and high pseudo-enhancement group(group B)There were 16 cases in group A and 23 cases in group B Comparisons weremade between the two groups on the parameters of the cysts，the vessels closest to the cysts，the vessels with the highest enhance-ment，and all the vessels around the cysts，such as a
9、rea，distance，CT value，etc esultsThe CT values of the cysts in arterialphase were higher than those in non-contrast phase，the difference was statistically significantand，P 0 05 The parameters suchas the CT values of the cysts in non-contrast phase，the cross-sectional areas of the cysts，the distances
10、between the nearest vesselsand the cysts，the average values of the distances between all the vessels around and the cysts in group A were higher than thosein group B，and there were significant differences of the four parameters above between the two groups，P 0 05 The distancesbetween the nearest ves
11、sels and the cysts had independent effect on pseudo-enhancement of mediastinal cyst，P 0 05 Conclu-sionPseudo-enhancement of cyst in the mediastinum exists objectively The main influencing factors of Pseudo-enhancement areCT values of the cysts in non-contrast phase，cross-sectional areas of the cysts
12、，the distances between the nearest vessels and the作者简介:朱振华(1985-)，男，毕业于泰山医学院，医学硕士，主治医师，主要从事医学影像学诊断工作通信作者:李海文E-mail:3101374743 qq com275医学影像学杂志 2023 年第 33 卷第 4 期J Med Imaging Vol33 No4 2023cysts，and the average values of the distances between all the vessels around and the cysts The distance between
13、the nearest ves-sel and the mediastinal cyst can independently affect the phenomenon of pseudo-enhancement【Key words】Mediastinum Cyst;Tomography，X-ray computed;Pseudo-enhancement纵隔囊肿是一组位于纵隔内的良性囊性病变1-3，其诊断主要依赖于 CT 增强检查。纵隔囊肿内没有实性成分和血供，但受假性强化现象的影响，增强扫描后其 CT 值会有一定程度的上升4-5。因此，CT 增强扫描在鉴别纵隔囊肿与乏血供肿瘤时可能会有困难，
14、影响对纵隔囊肿做出明确诊断4-6。文献报道7 进行了肾囊肿假性强化的研究，但纵隔囊肿假性强化的文献较少。本文将对可能导致纵隔囊肿假性强化的主要因素进行探讨。1资料与方法1 1一般资料选取2013 年1 月 2018 年12 月在我院手术病理证实为纵隔囊肿的患者 39 例，其中男性 16 例，女性 23 例，年龄 17 74 岁，平均年龄(55 5 13.0)岁。胸腺囊肿 26 例，纵隔支气管囊肿 7 例，心包囊肿 4 例，肠源性囊肿 2 例。将以上病例以增强扫描后囊肿 CT 值上升是否超过 10 HU 为标准分为两组，增强后病灶 CT 值上升小于 10 HU 者纳入低假性强化组(A 组)16
15、例，其余病例纳入高假性强化组(B 组)23 例。所有患者均在术前进行过胸部 CT 平扫及增强扫描。排除标准:1)病灶平扫显示密度不均或增强扫描显示有实性成分;2)增强扫描后病灶区有肉眼可见的射线硬化伪影，导致病灶明显密度不均。1 2检查方法采用 Somatom Definition CT 行胸部平扫及增强扫描，扫描范围自胸廓入口处向下至肋膈角，管电压120 kV，管电流采用 CAE Dose 4D 技术自动控制(Quality ref mAs110)，螺距 1 2，层厚 5 mm(Acq128 0 6 mm)。所有患者均采用双期增强扫描，动脉期采用 Blous tracking 技术进行触发，
16、触发阈值设为 100 HU。采用碘海醇(350 mg I/ml)作为对比剂。由肘正中静脉或前臂浅静脉用 20G 套管针穿刺，以 3 0 ml/s 速率注射对比剂和生理盐水，对比剂用量按照 1 5 ml/kg 体重进行计算，并统一在对比剂注射完毕后跟注生理盐水20 ml。平扫、增强扫描图像重建纵隔窗窗值(W350，C50)，重建卷积核B31f medium smoth。1 3图像处理测量数据均在西门子 CT 工作站进行。选取平扫、动脉期病灶最大横截面层面进行数据测量。分别测量所有患者病灶平扫、动脉期所示 CT 值。分别对两组患者病灶参数(平扫 CT 值、增强后 CT 值、截面积)、距病灶最近纵隔大血管或心腔参数(强化程度、面积、与病灶的距离)、病灶周围增强程度最高的血管或心腔参数(强化程度、面积、与病灶的距离)进行测量，CT 值测量 OI 兴趣区尽可能大但避开病灶边缘或血管壁，病灶、血管或心腔面积测量范围尽可能与其边缘一致，距离测量起止点分别取两测量目标的中心点。所有数据均由 1 位从事胸部CT 诊断 10 年以上影像医师进行测量，所有数据均测量 3 次并取平均值(图 1 4)。病灶周围