仿真三维CT血管内镜对脑动脉瘤的诊断价值及临床意义
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摘要
前言
仿真3D-CT血管内镜是计算机软件技术飞速发展的产物。它是利用计算机导航软件功能，在血管注入造影剂后将螺旋CT扫描获得的图像数据进行后处理，重建出血液铸形图像(Fly-around)以及血管腔内表面立体图像(Fly-through)，以模拟光学纤维内窥镜效果的方式来显示血管腔内结构，而获得血管腔三维或动态三维的解剖学图像。目前国内外应用此技术研究最多的是主动脉及其分支病变；国外学者还运用此技术成功地显示了肺栓塞患者肺动脉及其分支血管，清晰准确地显示肺动脉腔内的栓子；而对颅内动脉瘤特别是大的动脉瘤的研究表明：通过仿真3D-CT血管内镜成像，能清晰地显示脑动脉瘤的解剖细节，显示瘤体、瘤颈、管腔内部情况以及瘤腔内血栓等，并可作外科术前模拟，为临床提供准确独特且有价值的信息。然而它独立诊断脑动脉瘤价值的研究却极少。本实验意在评价应用仿真3D-CT血管内镜技术对以蛛网膜下腔出血(SAH)为首发症状的脑动脉瘤的诊断价值，并观察动脉瘤腔内血栓形成情况。
材料与方法
2000年10月至2001年10月中国医科大学第一临床学院神经内外科记载比较完整的自发性SAH患者46例，男29例，女17例，年龄17～69岁，平均45.3±13.0岁。所有患者均行多层面螺旋CT三维血管造影(3D-MSCTA)和数字减影血管造影(DSA)检查。其中31例接受手术治疗。多层面螺旋CT采集原始数据，扫描速度0.5s/每转，层厚1.0mm，对比剂安琪格纳芬：1.0～2.0ml/kg体重，注射速度：2.5～3.0ml/s，延迟时间：15～23s；SGI-
OZ图像后处理工作站，后处理软件为：ALATOVIEW，版本1·2＊
采用遮盖容积重建（SVR人多平面重建（MPR）和仿真 3 D－CT血
管内镜（un－。und；ny－through）三种后处理技术。DSA检查
用Mulh－Start·O·T瞩imens）经股动脉插管行常规全脑血管造影，
分别摄前后位、左侧位、右侧位、左前斜位 45”和右前斜位 45”图
像。所得 3 D－MSCTA图像和 DSA图像分别由 2位放射科医生和
2位脑外科医生采用双盲法进行评价。计量资料组间比较用t检
验，计数资料组间比较用X‘检验。
实验结果
（一）脑动脉瘤的检出结果
46例患者经仿真 3 D－CT血管内镜的 Fly－round成像方法
检出37例患者共有脑动脉瘤39个，经DSA和／或手术证实均准
确（真阳性人2例为多发脑动脉瘤，各有2个动脉瘤。瘤体、瘤颈
部及与周围血管的关系在Fly－round图像上均清楚显示。1例
多发脑动脉瘤患者经DSA及手术均证实为右侧小脑下后动脉瘤
和左后交通动脉瘤，Fly－round图像只检出右侧小脑下后动脉
瘤，而漏检左后交通动脉瘤（假阴性人另9例患者SVR、ly－a－
round和DSA均未检出动脉瘤（真阴性人无假阳性结果。敏感性
为98％，特异性100％，准确性98％。
用SVR成像共检出上述39个动脉瘤中的37个，除漏检心
一rotmd未检出的一个动脉瘤外，还漏检了右侧大脑后动脉瘤厂
．7turn）和右侧大脑前动脉瘤（3．4nun）两个动脉瘤。敏感性、特异
性和准确性钢u为 93％＊％s4％。
DSA检出37例患者38个动脉瘤，3例多发，各有2个动脉
瘤，漏检2个单发动脉瘤。
SVR、Fy－round、DSA三者检出率分别为 93％、98阮＼95畅。
它们之间的差异，无统计学意义。Fly－round及 DSA测量动脉瘤
·2·
最大直径经检验，两种方法测量值统计学上无显著差异。
（二）瘤内血栓形成情况
Fly叫hroll如图像显示动脉瘤内附壁血栓形成 6个门％X
均经MPR图像证实。此6个动脉瘤均为单发，6例患者中5例接
受脑动脉瘤夹闭术治疗，4例愈后良好，互例术前发生严重的脑梗
塞，术后仍有肢体瘫痪；另1例患者被确诊后放弃治疗。
讨 论
一、仿真 3 D－CT血管内镜技术诊断脑动脉瘤的价值
脑动脉瘤的破裂是自发性SAH最常见的病因，患者早期病死
率高达36％－45％。病程中还可出现脑血管痉挛、缺血性脑梗死
和再出血等严重的并发症，故早期诊断至关重要。如为脑动脉瘤
破裂所致SAH，有效的根治方法是实施早期夹闭手术或血管内栓
塞冶疗。DSA是目前公认的诊断脑动脉瘤的金标准，但此为有创
性检查，潜在着发生并发症的危险。
近年来国外有关研究表明：3 D－CTA诊断脑动脉瘤具有很高
的敏感性。然而，仿真 3 D－CT血管内镜在发现动脉瘤方面究竟
起了多大的作用却极少有人提及。因为它能对颅内动脉进行选择
性的灌注，形成的Fly－round图像大，能更清晰、直观地显示动脉
瘤及载瘤血管的解剖细节，其图像可做任意角度旋转，并有测量功
能，故它的诊断价值将越来越受到重视。本实验 46例患者经 Fly
－round成像方法检出37例患者共有脑动脉瘤39个，经DSA和
／或手术证实均准确，敏感性为98％、特异性100％、准确性98％。
其中有2个相对小的动脉瘤被Fly－。una图像清晰显示，而SVR
成像方法未能检出。这初步显示了 3 D－CT血管内镜诊断较小的
动脉瘤的优势，从而也提醒操作医师，疑诊动脉瘤患者，SVR未发
现动脉瘤，应?
Preface
Virtual vascular 3D - CT endoscopy is a recently developed imaging modality. 3D images of this technique (include Fly -around and Fly - through) were obtained using a new processing technique which extracts CT number in the boundary region between the vessel wall and contrasts media filled in the vascular lumen. Clinical application of this technique to cerebral aneurysms, particularly to complicated large cerebral aneurysms showed that, with this virtual vascular 3D - CT endoscopic imaging, anatomical details of cerebral aneurysms such as the orifice of the aneurysm^the neck of the aneurysm and intraluminal thrombus could be demonstrated clearly. Using a 3 - D imaging method by Helical CT, virtual views of various surgical approaches were compared preoperatively. But its diagnostic value alone in the cerebral aneurysms was less studied. In this retrospective study, we evaluated the diagnostic value and clinical significance of virtual vascular 3D -CT endoscopy as a method for cerebral aneurysms in patients
with spontaneous subarachnoid hemorrhage.
Materials and methods
1. Material
In present study, 46 patients(29 men, 17 women, age 17 to 69 years, mean age 45.3 ± 13. 0 years) who presented with spontaneous SAH, underwent both 3D - MSCTA and DSA. 29 patients of them accepted surgical clipping, and 2 patients of them accepted endovasular embolization.
2. Method
Row data was acquired by Multi - slice helical CT - AQUILION (Toshiba) : The scan speed 0.5s/rot, image slice thickness 1.0mm, helical pitch 3.0/5.0 . Contrast media (Angiografin) was injected intravenously (1.0 - 2. 0ml/kg) at speed of 2. 5 - 3. 0ml/s, delay time was 15 - 23s, reconstruction interval 0. 5mm, reconstruction slice thickness 1.0mm. Source images were processed using a workstation SGI - 02, images post - processing software was ALATO-VIEW, version 1.21. The reconstructed images were then processed into SVR, MPR, Fly - around and Fly -through images. Entire brain DSA was performed obtaining anterioposterior, lateral, and oblique images. Images of 3D - MSCTA and DSA were analysed by 2 radiologists and 2 neurosurgeons, with assessment of 3 D - MSCTA and DSA finding respectively.
Results
A total of 39 aneurysms were detected in 37 patients by Fly - a-round image and were confirmed by DSA and/or operation method (true positives). 35 patients sustained single aneurysm, 2 patients sustained two. In one case, two aneurysms were defected by DSA and
confirmed by surgery, but only one was demonstrated by Fly - around image (false negative). The presence of cerebral aneurysms was excluded at SVR and Fly - around and DSA in 9 patients (true negatives). There were no false positives. The mean maximal diameter of aneurysms body was 6. 21 ±4. 33mm. Sensitivity was 98% , Specificity was 100% , diagnostic accuracy was 98% .
37 aneurysms were demonstrated and 3 aneurysms were no detected by SVR.
DSA revealed 38 aneurysms in 37 patients, 35 patients sustained one aneurysm, 3 patients sustained two. 2 single aneurysms were not detected. The mean maximal diameter of aneurysms body was 6.15 ± 4. 29mm. There was not statistic differences between the measurement of Fly - around and DSA about the size of the aneurysm body (t = 1. 42 ,P >0. 05). The finding rate of the aneurysms of Fly - around and SVR and DSA was 98% ,93% and 95% , respectively. There were no statistic differences among them.
Intraluminal thrombus was detected in 6 singe aneurysms by virtual vascular 3D - CT endoscopy ( Fly - through) and confirmed by MPR.
Discussion
1. The value of virtual vascular 3D - CT endoscopy in the detection and evaluation of aneurysms.
The common reasons of SAH is ruptured cerebral aneurysms. The mortality remains 36% -45% in the early stage of the illness. So it is important to diagnose early. The effective treatment is surgical clipping or endovasculax embolization of cerebral aneurysms. DSA was regarded as the gold standard of diagnosis in the cerebral aneurysms,
but it is an invasive method. As a rapid and non
仿真3D-CT血管内镜是计算机软件技术飞速发展的产物。它是利用计算机导航软件功能，在血管注入造影剂后将螺旋CT扫描获得的图像数据进行后处理，重建出血液铸形图像(Fly-around)以及血管腔内表面立体图像(Fly-through)，以模拟光学纤维内窥镜效果的方式来显示血管腔内结构，而获得血管腔三维或动态三维的解剖学图像。目前国内外应用此技术研究最多的是主动脉及其分支病变；国外学者还运用此技术成功地显示了肺栓塞患者肺动脉及其分支血管，清晰准确地显示肺动脉腔内的栓子；而对颅内动脉瘤特别是大的动脉瘤的研究表明：通过仿真3D-CT血管内镜成像，能清晰地显示脑动脉瘤的解剖细节，显示瘤体、瘤颈、管腔内部情况以及瘤腔内血栓等，并可作外科术前模拟，为临床提供准确独特且有价值的信息。然而它独立诊断脑动脉瘤价值的研究却极少。本实验意在评价应用仿真3D-CT血管内镜技术对以蛛网膜下腔出血(SAH)为首发症状的脑动脉瘤的诊断价值，并观察动脉瘤腔内血栓形成情况。
材料与方法
2000年10月至2001年10月中国医科大学第一临床学院神经内外科记载比较完整的自发性SAH患者46例，男29例，女17例，年龄17～69岁，平均45.3±13.0岁。所有患者均行多层面螺旋CT三维血管造影(3D-MSCTA)和数字减影血管造影(DSA)检查。其中31例接受手术治疗。多层面螺旋CT采集原始数据，扫描速度0.5s/每转，层厚1.0mm，对比剂安琪格纳芬：1.0～2.0ml/kg体重，注射速度：2.5～3.0ml/s，延迟时间：15～23s；SGI-
OZ图像后处理工作站，后处理软件为：ALATOVIEW，版本1·2＊
采用遮盖容积重建（SVR人多平面重建（MPR）和仿真 3 D－CT血
管内镜（un－。und；ny－through）三种后处理技术。DSA检查
用Mulh－Start·O·T瞩imens）经股动脉插管行常规全脑血管造影，
分别摄前后位、左侧位、右侧位、左前斜位 45”和右前斜位 45”图
像。所得 3 D－MSCTA图像和 DSA图像分别由 2位放射科医生和
2位脑外科医生采用双盲法进行评价。计量资料组间比较用t检
验，计数资料组间比较用X‘检验。
实验结果
（一）脑动脉瘤的检出结果
46例患者经仿真 3 D－CT血管内镜的 Fly－round成像方法
检出37例患者共有脑动脉瘤39个，经DSA和／或手术证实均准
确（真阳性人2例为多发脑动脉瘤，各有2个动脉瘤。瘤体、瘤颈
部及与周围血管的关系在Fly－round图像上均清楚显示。1例
多发脑动脉瘤患者经DSA及手术均证实为右侧小脑下后动脉瘤
和左后交通动脉瘤，Fly－round图像只检出右侧小脑下后动脉
瘤，而漏检左后交通动脉瘤（假阴性人另9例患者SVR、ly－a－
round和DSA均未检出动脉瘤（真阴性人无假阳性结果。敏感性
为98％，特异性100％，准确性98％。
用SVR成像共检出上述39个动脉瘤中的37个，除漏检心
一rotmd未检出的一个动脉瘤外，还漏检了右侧大脑后动脉瘤厂
．7turn）和右侧大脑前动脉瘤（3．4nun）两个动脉瘤。敏感性、特异
性和准确性钢u为 93％＊％s4％。
DSA检出37例患者38个动脉瘤，3例多发，各有2个动脉
瘤，漏检2个单发动脉瘤。
SVR、Fy－round、DSA三者检出率分别为 93％、98阮＼95畅。
它们之间的差异，无统计学意义。Fly－round及 DSA测量动脉瘤
·2·
最大直径经检验，两种方法测量值统计学上无显著差异。
（二）瘤内血栓形成情况
Fly叫hroll如图像显示动脉瘤内附壁血栓形成 6个门％X
均经MPR图像证实。此6个动脉瘤均为单发，6例患者中5例接
受脑动脉瘤夹闭术治疗，4例愈后良好，互例术前发生严重的脑梗
塞，术后仍有肢体瘫痪；另1例患者被确诊后放弃治疗。
讨 论
一、仿真 3 D－CT血管内镜技术诊断脑动脉瘤的价值
脑动脉瘤的破裂是自发性SAH最常见的病因，患者早期病死
率高达36％－45％。病程中还可出现脑血管痉挛、缺血性脑梗死
和再出血等严重的并发症，故早期诊断至关重要。如为脑动脉瘤
破裂所致SAH，有效的根治方法是实施早期夹闭手术或血管内栓
塞冶疗。DSA是目前公认的诊断脑动脉瘤的金标准，但此为有创
性检查，潜在着发生并发症的危险。
近年来国外有关研究表明：3 D－CTA诊断脑动脉瘤具有很高
的敏感性。然而，仿真 3 D－CT血管内镜在发现动脉瘤方面究竟
起了多大的作用却极少有人提及。因为它能对颅内动脉进行选择
性的灌注，形成的Fly－round图像大，能更清晰、直观地显示动脉
瘤及载瘤血管的解剖细节，其图像可做任意角度旋转，并有测量功
能，故它的诊断价值将越来越受到重视。本实验 46例患者经 Fly
－round成像方法检出37例患者共有脑动脉瘤39个，经DSA和
／或手术证实均准确，敏感性为98％、特异性100％、准确性98％。
其中有2个相对小的动脉瘤被Fly－。una图像清晰显示，而SVR
成像方法未能检出。这初步显示了 3 D－CT血管内镜诊断较小的
动脉瘤的优势，从而也提醒操作医师，疑诊动脉瘤患者，SVR未发
现动脉瘤，应?
Preface
Virtual vascular 3D - CT endoscopy is a recently developed imaging modality. 3D images of this technique (include Fly -around and Fly - through) were obtained using a new processing technique which extracts CT number in the boundary region between the vessel wall and contrasts media filled in the vascular lumen. Clinical application of this technique to cerebral aneurysms, particularly to complicated large cerebral aneurysms showed that, with this virtual vascular 3D - CT endoscopic imaging, anatomical details of cerebral aneurysms such as the orifice of the aneurysm^the neck of the aneurysm and intraluminal thrombus could be demonstrated clearly. Using a 3 - D imaging method by Helical CT, virtual views of various surgical approaches were compared preoperatively. But its diagnostic value alone in the cerebral aneurysms was less studied. In this retrospective study, we evaluated the diagnostic value and clinical significance of virtual vascular 3D -CT endoscopy as a method for cerebral aneurysms in patients
with spontaneous subarachnoid hemorrhage.
Materials and methods
1. Material
In present study, 46 patients(29 men, 17 women, age 17 to 69 years, mean age 45.3 ± 13. 0 years) who presented with spontaneous SAH, underwent both 3D - MSCTA and DSA. 29 patients of them accepted surgical clipping, and 2 patients of them accepted endovasular embolization.
2. Method
Row data was acquired by Multi - slice helical CT - AQUILION (Toshiba) : The scan speed 0.5s/rot, image slice thickness 1.0mm, helical pitch 3.0/5.0 . Contrast media (Angiografin) was injected intravenously (1.0 - 2. 0ml/kg) at speed of 2. 5 - 3. 0ml/s, delay time was 15 - 23s, reconstruction interval 0. 5mm, reconstruction slice thickness 1.0mm. Source images were processed using a workstation SGI - 02, images post - processing software was ALATO-VIEW, version 1.21. The reconstructed images were then processed into SVR, MPR, Fly - around and Fly -through images. Entire brain DSA was performed obtaining anterioposterior, lateral, and oblique images. Images of 3D - MSCTA and DSA were analysed by 2 radiologists and 2 neurosurgeons, with assessment of 3 D - MSCTA and DSA finding respectively.
Results
A total of 39 aneurysms were detected in 37 patients by Fly - a-round image and were confirmed by DSA and/or operation method (true positives). 35 patients sustained single aneurysm, 2 patients sustained two. In one case, two aneurysms were defected by DSA and
confirmed by surgery, but only one was demonstrated by Fly - around image (false negative). The presence of cerebral aneurysms was excluded at SVR and Fly - around and DSA in 9 patients (true negatives). There were no false positives. The mean maximal diameter of aneurysms body was 6. 21 ±4. 33mm. Sensitivity was 98% , Specificity was 100% , diagnostic accuracy was 98% .
37 aneurysms were demonstrated and 3 aneurysms were no detected by SVR.
DSA revealed 38 aneurysms in 37 patients, 35 patients sustained one aneurysm, 3 patients sustained two. 2 single aneurysms were not detected. The mean maximal diameter of aneurysms body was 6.15 ± 4. 29mm. There was not statistic differences between the measurement of Fly - around and DSA about the size of the aneurysm body (t = 1. 42 ,P >0. 05). The finding rate of the aneurysms of Fly - around and SVR and DSA was 98% ,93% and 95% , respectively. There were no statistic differences among them.
Intraluminal thrombus was detected in 6 singe aneurysms by virtual vascular 3D - CT endoscopy ( Fly - through) and confirmed by MPR.
Discussion
1. The value of virtual vascular 3D - CT endoscopy in the detection and evaluation of aneurysms.
The common reasons of SAH is ruptured cerebral aneurysms. The mortality remains 36% -45% in the early stage of the illness. So it is important to diagnose early. The effective treatment is surgical clipping or endovasculax embolization of cerebral aneurysms. DSA was regarded as the gold standard of diagnosis in the cerebral aneurysms,
but it is an invasive method. As a rapid and non
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brai aneurysms with a modified surface-rendering technique of spiral CT. Acta Neurochir (Wien), 2000,142:1003-1012.
15. Freund M, Thomsen M, Hohendorf B, et al, Optimized preoperative planning of calcaneal fractures using spiral computed tomography. Eur Radiol, 1999,9:901-906.
16．刘云会，程鹏，译。介入神经放射治疗。见：高旭光，主译。卒中。第1版。沈阳：辽宁科学技术出版社，2001，1034-1042．
17．高旭光，译。颅内动脉瘤。见：高旭光，主译。卒中。第1版。沈阳：辽宁科学技术出版社，2001，568-585．
18. Neri E, Caramella D. Virtual CT Interavascular endoscopy of the aorta: Piereced surface and floating shape thresholding Artifacts. Radiology, 1999, 212: 276-279.