双源CT低剂量前瞻性心电门控扫描在双侧双向Glenn术后患儿中的应用

发布时间：2018-03-29 15:41

本文选题：双侧双向Glenn分流术　切入点：双源CT　出处：《山东大学》2015年博士论文

【摘要】：第一部分双源CT低剂量前瞻性心电门控步进式扫描在搏动性双侧双向Glenn术后患儿中的临床应用目的：探讨双源CT低剂量前瞻性心电门控步进式扫描(简称低剂量步进式扫描)技术作为一种无创的形态学方面的评价方法在搏动性双侧双向Glenn术后患儿中的应用价值。方法：前瞻性收集20例搏动性双侧双向Glenn术后患儿(平均年龄为4.2±1.6岁,范围2-6岁；男15例,女5例；平均体重15.4±3.7 kg,范围10-21 kg),于低剂量步进式扫描后1周内行传统心血管造影检查(conventional cardiac angiography, CCA)。步进式扫描参数设置：探测器准直为2×32×0.6mm,球管旋转时间为0.33s/r,采集时间窗预设为40%R-R间期,管电压为80kV,管电流根据患儿体重调节：体重不超过6kg,每kg增加lOmAs,体重超过6kg,超出部分在60mAs基础上每kg增加5mAs,管电流最大140 mAs。由两名具备五年以上心血管影像诊断经验的医师采用5分法对图像质量进行主观评价,运用Kappa检验评价两名医师对图像质量主观评价的一致性。测量患儿双侧上腔静脉及肺动脉的CT值及噪声。术后患儿的形态学评价包括,双侧上腔静脉和肺动脉的形态测量,上腔静脉和肺动脉的吻合位置关系,是否出现血栓形成、体肺侧支循环及肺动静脉畸形等,以CCA结果作为金标准,运用Bland-Altman检验和线性回归分析评价CT血管造影(CT angiography,CTA)和CCA的符合程度并计算Pearson's相关系数。计算低剂量步进式扫描和CCA的有效辐射剂量(effective dose, ED)。结果：左侧上腔静脉、右侧上腔静脉、左侧肺动脉、右侧肺动脉的强化CT值分别为351.1±52.3HU、353.8±60.4HU、345.7±57.OHU、356.5±67.6HU,噪声分别为26.4±4.1HU、24.5±5.4HU、25.2±3.7HU、24.5±4.4HU。所有图像均满足诊断要求,其中5分5例,4分11例,3分4例,图像质量主观评分平均为4.05±0.69,两名医师的一致性好(k=0.76,P0.05)。低剂量步进式扫描可以全面直观地显示双侧上腔静脉和肺动脉,发现14支上腔静脉管腔扩张,16处肺动脉局限性狭窄。61.5%(24/39)的上腔静脉吻合于肺动脉上方,38.5%(15/39)的上腔静脉吻合于肺动脉前方。1例患儿发现血栓形成。13例患儿发现33支体-肺循环侧支血管,其中发现2支侧支血管者6例,3支侧支血管者7例；33支侧支血管中起自主动脉弓2支、降主动脉15支、肋间动脉8支、左锁骨下动脉2支、左胸廓内动脉2支、左椎动脉1支、右胸廓内动脉3支。20例患儿没有发现肺动静脉畸形。CTA在形态测量方面与CCA的一致性好(R10.8,P0.001)。Bland-Altman检验表明CTA测量值在一定程度上偏大(平均偏倚值0)。低剂量步进式扫描平均ED为0.50±0.17 mSv(0.27-0.89 mSv)；CCA平均ED为4.85±1.34 mSv(3.07-6.72 mSv)。结论：双源CT低剂量前瞻性心电门控步进式扫描可以准确地对保留前向血流的双侧双向Glenn术后患儿进行形态学方面的评价,简便无创且辐射剂量低。第二部分128层双源CT低剂量前瞻性心电门控大螺距扫描结合迭代重建在双侧双向Glenn术后患儿中的临床应用目的：探讨128层双源CT低剂量前瞻性心电门控大螺距扫描(简称低剂量大螺距扫描)结合迭代重建技术在双侧双向Glenn术后患儿中的临床应用价值,并将管电压70kV组与80kV组的图像质量及辐射剂量进行比较,以探索70kV应用于双侧双向Glenn术后患儿的可行性。方法：前瞻性收集双侧双向Glenn术后患儿40例,随机分为A、B两组,A组患儿20例(平均年龄为5.4±3.0岁,范围1-10岁；男8例,女12例；平均体重19.2±6.9 kg,范围10-31 kg)行80kV低剂量大螺距扫描,B组患儿20例(平均年龄为5.3±2.7岁,范围1-10岁；男9例,女11例；平均体重18.8±5.6 kg,范围9-30 kg)行70kV低剂量大螺距扫描。所有患儿于低剂量大螺距扫描后1周内行传统心血管造影检查(conventional cardiac angiography, CCA)。大螺距扫描参数设置：探测器准直为2×64×0.6mm,球管旋转时间为0.28s/r,螺距为3.4,数据采集起始时相预设为10%R-R间期；A组管电压为80kV,管电流根据患儿体重调节：不超过6kg,管电流为10mAs/kg,6kg以上,管电流在60mAs的基础上增加5mAs/kg; B组管电压为70kV,管电流在A组的计算方法所得管电流基础上增加20mAs。记录两组的扫描长度和扫描时间。运用基于原始数据的迭代重建技术获得薄层图像,重建强度为3,卷积核为I26f。将薄层图像传输至工作站进行图像后处理。由两名具备五年以上心血管影像诊断经验的医师采用5分法对图像质量进行主观评价。分别测量两组图像的升主动脉根部、胸背部肌肉、双侧上腔静脉及肺动脉的CT值和噪声,计算升主动脉根部的信噪比(signal-to-noise ratio, SNR)和对比噪声比(contrast-to-noise ratio,CNR)。计算有效辐射剂量(effective dose, ED)。采用Student's t检验比较两组患儿的一般资料、图像CT值、噪声、SNR、CNR及ED,采用Mann-Whitney U检验比较两组图像质量主观评分,采用Kappa检验比较两名医师对图像质量主观评分的一致性。观察患儿术后双侧上腔静脉有无扩张、肺动脉有无狭窄、体-肺循环侧支血管数目、有无血栓形成及肺动静脉畸形情况,并以CCA结果作为标准,评价两组图像的诊断准确性。结果：所有双侧双向G1enn术后患儿均成功完成低剂量大螺距扫描。两组患儿的年龄(t=0.054,P0.05)、体重(t=0.176,P0.05)、心率(t=0.461,P0.05)、扫描长度(t=0.393,P0.05)及扫描时间(t=0.250,P0.05)差别无统计学意义。A、B两组患儿CT图像的升主动脉CT值分别为323.1±55.3HU、361.7±61.6HU(t=2.086,P0.05),差异有统计学意义,B组高于A组；升主动脉的噪声、SNR、CNR(t=1.586、0.884、1.028,P0.05),差别均无统计学意义。两组图像的左上腔静脉、右上腔静脉、左肺动脉及右肺动脉的CT值(t=2.288、2.476、2.495、2.216,P0.05)差异有统计学意义,B组高于A组；左上腔静脉、右上腔静脉、左肺动脉及右肺动脉的噪声(t=1.535、1.610、1.366、1.159,P0.05)差别无统计学意义。两组所有患儿图像均满足诊断要求,A组5分8例,4分10例,3分2例,B组5分6例,4分11例,3分3例；两名医师的一致性好(k=0.74、0.75,P0.05)。A、B组图像质量主观评价平均得分分别为4.30±0.66、4.15±0.67(u=176.00,P0.05),主观评分差别无统计学意义。所有患儿的图像均未出现运动伪影。CT发现发现上腔静脉扩张17处(A组9处,B组8处),肺动脉狭窄10处(A组5处,B组5处)；体-肺循环侧支血管49支(A组23支,B组26支),所有患儿均未发现血栓形成及动静脉畸形形成。以CCA结果作为标准,两组诊断准确率均为100%。A、B两组的ED平均分别为0.32±0.12 mSv.0.25±0.08mSv(t=2.128,P0.05),差异有统计学意义,B组小于A组。结论：128层双源CT低剂量前瞻性心电门控大螺距扫描结合迭代重建技术在双侧双向Glenn术后患儿中可以低辐射剂量获取满足诊断的图像,并且将管电压由80kV降至70kV后图像强化程度提高的同时图像质量无明显下降,70kV可以用于双侧双向Glenn术后患儿形态学方面的评价。
[Abstract]:Objective : To investigate the clinical application of double - source CT low - dose forward - looking heart - gated progressive scan in pediatric patients with dual - sided and double - sided , double - source CT . Methods : To investigate the application value of double - source CT low - dose forward - looking heart - gated progressive scanning technique as a noninvasive morphological aspect in children with dual - sided and double - sided , double - source CT . Methods : Twenty cases of bilateral bilateral bilateral bidirectional cardiac surgery were prospectively collected ( mean age : 4.2 卤 1.6 years , range 2 - 6 years ) .
There were 15 males and 5 females .
Mean body weight was 15.4 卤 3.7 kg ( range 10 - 21 kg ) , and conventional cardiac angiography ( CCA ) was performed within 1 week after low - dose progressive scan . The results were as follows : collimation of the detector is 2 脳 32 脳 0.6mm , the rotation time of the ball tube is 0.33s / r , the acquisition time window is preset to 40 % R - R interval , the tube voltage is 80kV , the tube current is more than 6 kg per kg and the tube current is up to 140 mAs . Results : The enhanced CT values of left superior vena cava , right superior vena cava , left pulmonary artery and right pulmonary artery were 351.1 卤 52.3HU , 353.8 卤 60.4 HU , 345.7 卤 57.OHU , 356.5 卤 67.6 HU , respectively , and the noise was 26 . 4 卤 4 . 1 HU , 24.5 卤 5.4 HU , 25 . 2 卤 3 . 7HU , 24.5 卤 4.4 HU respectively . Low - dose progressive scan showed that the superior vena cava and pulmonary artery in bilateral superior vena cava were fully and intuitively displayed , 14 superior vena cava lumen were dilated , 16 pulmonary artery stenosis was found at 16 . The superior vena cava at 38.5 % ( 24 / 39 ) was anastomosed to the pulmonary artery , 38.5 % ( 15 / 39 ) of superior vena cava was anastomosed to the pulmonary artery .
Among the 33 collateral vessels , 2 branches from the aortic arch , 15 branches of descending aorta , 8 branches of intercostals , 2 branches of the lower left clavian artery , 2 branches of the left thoracic artery , 1 left vertebral artery and 3 branches of the right thoracic artery . The Bland - Altman test showed that the CTA measurements were somewhat larger ( mean bias value 0 ) . The mean ED of the low - dose progressive scan was 0.50 卤 0.17 ( 0.27 - 0.89 ) .
The average ED of CCA is 4.85 卤 1.34 ( 3.07 - 6.72 ) . Objective : To investigate the clinical application value of double - source CT low - dose prospective ECG gated large - pitch scanning combined with iterative reconstruction in the pediatric patients with bilateral two - sided and two - sided and two - sided and two - sided patients after bilateral two - way , double - source CT . Methods : Forty - four children with double - source CT were randomly divided into two groups : group A , group B , and group A : 20 cases ( mean age 5.4 卤 3.0 years , range 1 - 10 years ) .
8 males and 12 females ;
The average body weight was 19.2 卤 6.9 kg ( range 10 - 31 kg ) , 80 kV low - dose long - pitch scan , 20 children in group B ( mean age 5.3 卤 2.7 years , range 1 - 10 years ) ;
There were 9 males and 11 females .
The average body weight was 18 . 8 卤 5.6 kg ( range 9 - 30 kg ) at 70 kV low - dose long - pitch scan . All children underwent conventional cardiac angiography ( CCA ) within 1 week after low - dose large - pitch scanning . Parameter setting of large pitch scanning : the collimation of the detector is 2 脳 64 脳 0.6mm , the rotation time of the bulb is 0.28 s / r , the pitch is 3.4 , and the phase preset at the start of data acquisition is 10 % R - R interval ;
A group A tube voltage is 80kV , the tube current is adjusted according to the weight of the child : no more than 6kg , the tube current is 10mAs / kg , 6kg or more , the tube current is increased by 5mAs / kg on the basis of 60mAs , the tube current is increased by 20mAs on the basis of 60mAs . Effective dose ( ED ) was calculated . Results : The CT values of ascending aorta were 323.1 卤 55.3HU , 361.7 卤 61.6HU ( t = 2.086 , P0.05 ) .
The noise , SNR , CNR ( t = 1.586 , 0.884 , 1.028 , P0.05 ) of ascending aorta were not statistically significant . The difference of left superior vena cava , right superior vena cava , left pulmonary artery and right pulmonary artery was significant ( t = 2.288 , 2.476 , 2.495 , 2.216 , P0.05 ) .
There was no significant difference between the left superior vena cava , the right superior vena cava , the left pulmonary artery and the right pulmonary artery ( t = 1.535 , 1.610 , 1.366 , 1.159 , P0.05 ) .
The average scores of subjective evaluation of image quality in group A and B were 4.30 卤 0.66 , 4.15 卤 0.67 ( u = 176.00 , P0.05 ) .
There were 49 branches ( 23 branches in group A and 26 branches in group B ) on the side branch of the body - pulmonary circulation . All the children had no thrombosis and arteriovenous malformations . The diagnostic accuracy of the two groups was 0 . 32 卤 0.12 , 0 . 25 卤 0 . 08 ( t = 2.128 , P < 0 . 05 ) .

【学位授予单位】：山东大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：R726.5;R816.92

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