【作者】 郭燕舞；

【导师】 徐如祥；

【作者基本信息】 南方医科大学 ， 神经外科学， 2008， 博士

【摘要】 研究背景神经外科手术是所有外科手术中难度最大、最精细的手术之一。微创神经外科是二十一世纪神经外科的升华,对神经外科医生来讲,根据病人情况选择最适合的手术入路和进行个体化的手术操作是非常必要的。因此,术前进行准确、直观和个体化的手术计划和模拟,是神经外科发展的需要。基于虚拟现实技术的Dextroscope手术计划系统是目前最具应用前景的手术计划工具之一。它能够在虚拟现实状态下对CT、MRI等影像资料状态进行快速三维重建,并可对重建图像进行旋转、缩放、分割、融合等处理,还能应用模拟手术工具对立体三维图像进行多种仿真手术模拟处理,使手术医生能更直观和详细地了解手术区域的解剖关系,制定合适和准确的手术计划。在欧美等发达国家,该系统在大医院或神经外科中心正逐步得到应用。国内几家大的神经外科中心自2005年开始使用。本研究拟深入开展Dextroscope手术计划系统在神经外科的临床应用研究,选择颅内破裂动脉瘤和颅底肿瘤作为主要的研究方向,重点进行虚拟现实技术在动脉瘤诊断、开颅夹闭手术以及颅底肿瘤手术中的临床应用研究。对于该系统能否真正提高诊断准确率、提高神经外科手术水平、减少并发症、降低死亡率等一系列临床应用问题进行探讨,并评价该系统临床应用的可行性。第一章虚拟现实技术在颅内动脉瘤早期诊断中的应用Dextroscope系统介绍Dextroscope系统是由新加坡VI(Volume Interactions)公司研制的一套基于虚拟现实技术的手术计划系统,它通过对必要的影像资料进行加工和处理,可提供有用的诊断信息和外科治疗计划。Dextroscope系统由Dextroscope硬件系统和RadioDexter软件系统组成。RadioDexter是一种将先进的虚拟现实技术与实时体积测量和三维透视相结合的医学成像软件系统,它可以利用CT、MRI等影像资料创造出一种具有立体效果的虚拟现实环境,用户可以利用双手通过“进入”的方式,利用实时三维数据进行交互式的工作。RadioDexter可将同一病人不同类型的影像资料进行融合,所生成的三维图像有更加丰富的信息。RadioDexter也可对图像进行分割处理,使手术医生能对手术区域各部分的结构有更清晰的认识。利用左右手工具和系统提供的测量、染色、模拟手术等工具,可以很简便地对虚拟三维图像进行各种操作。研究目的通过对临床SAH患者进行3D-CTA检查并运用虚拟现实手术计划系统进行辅助诊断,研究虚拟现实技术结合3D-CTA手段对破裂性颅内动脉瘤的珍断价值,比较此方法与经典的DSA方法对颅内动脉瘤的诊断效能,探讨虚拟现实技术在破裂性颅内动脉瘤早期诊断中的应用价值。材料与方法选择南方医科大学珠江医院2005年12月至2006年12月收治的急性SAH患者80例,先利用3D-CTA和虚拟现实手术计划系统进行影像学诊断,再对所有诊断为阳性和阴性的病例进行DSA检查。对阴性病例进行密切观察和随访,1月后重复前述步骤进行诊断。研究3D-CTA和虚拟现实手术计划系统对破裂性颅内动脉瘤早期诊断的价值,比较该方法与DSA方法诊断动脉瘤的优缺点和诊断效能。本章无统计学分析内容,仅对所得结果进行统计学描述。研究结果经首次3D-CTA和虚拟现实手术计划系统诊断,80例患者中确诊68例73个动脉瘤,其中2例合并有动静脉畸形,4例为多发动脉瘤。另有5例诊断为动静脉畸形,2例诊断为烟雾病,其余5例无阳性发现。68例经3D-CTA和虚拟现实手术计划系统诊断为动脉瘤的患者行DSA检查确认,未发现假阳性病例;5例阴性病例再行DSA检查,结果亦无阳性发现。1月后对5例阴性病人再次行3D-CTA检查和虚拟现实手术计划系统诊断,又有2例检出2个动脉瘤,此2例亦经DSA检查得到确认。另3例未检出者DSA检查亦为阴性。68例均成功地进行了三维立体的虚拟影像重建。虚拟现实图像能够更清楚地显示动脉瘤的部位、大小和轮廓,尤其对于动脉瘤的瘤颈及其与载瘤动脉的关系显示非常满意。与3D-CTA及3D-DSA的图像相比,三维立体的虚拟影像更加清晰、逼真,并可根据需要随意进行旋转、缩放、分离、融合等操作,比传统的平面三维图像更直观和准确地显示动脉瘤与毗邻血管、颅骨结构的关系。利用仿真血管内窥镜工具可观察血管内壁和瘤腔的血栓形成、钙化、分隔等情况,并可清晰地显示瘤颈形态,为外科手术提供有用信息。所有患者均成功进行了DSA检查,部分加行旋转三维DSA检查。对经过3D-CTA和虚拟现实手术计划系统诊断的病例,经DSA再次诊断,未发现假阳性和假阴性结果。DSA可清楚得显示动脉瘤的位置、大小、形状、载瘤动脉。结合3D-DSA,对一些微小和复杂病例的诊断也比较明确。但DSA无法显示动脉与颅骨等结构的解剖关系,三维重建的图像也没有3D-CTA图像和虚拟现实手术计划系统的虚拟图像清晰和直观。80例患者首次3D-CTA诊断的结果:灵敏度97.1%(68/70),特异度100%(10/10);两次3D-CTA诊断的综合结果:灵敏度100%(70/70),特异度100%(10/10)。此结果与DSA的诊断结果完全一致。研究结论1、3D-CTA是一种方便、快捷、可靠的非侵袭性诊断方法,其对颅内动脉瘤的诊断效能与DSA(或3D-DSA)相同,可以作为破裂颅内动脉瘤诊治的首选影像检查。在动脉瘤急诊手术时CTA较DSA更具优越性。在术后复查及随访研究方面具有重要的临床应用价值。2、与DSA(或3D-DSA)相比,3D-CTA的图像更清晰,并能准确显示动脉瘤及载瘤动脉与颅骨的解剖关系,可观察到载瘤动脉和瘤腔内的钙化、分隔、血栓形成等情况。但3D-CTA不能显示血流方向,对有静脉窦干扰的动脉瘤显示欠佳。3、Dextroscope系统的操作比3D-CTA的图像工作站更加简便,其生成的三维立体虚拟影像更加清晰、逼真,并可进行随意旋转、缩放、分离、融合等操作,比3D-CTA的平面三维图像更直观准确地显示动脉瘤与毗邻血管、颅骨结构的关系。4、利用虚拟现实手术计划系统的仿真血管内窥镜工具,动脉瘤的瘤颈和瘤体形态以及瘤腔及载瘤动脉内的钙化、血栓和分隔等情况可被清晰呈现,部分动脉瘤甚至能提示破口位置。5、虚拟现实手术计划系统能够提高颅内动脉瘤的诊断精确性,给外科医生提供清晰、直观且准确的动脉瘤及毗邻血管和骨性结构的图像,为血管内治疗或开颅手术提供有用信息。第二章虚拟现实技术在颅内动脉瘤显微外科手术中的应用研究目的对开颅夹闭手术的颅内动脉瘤患者,术前进行虚拟现实手术计划系统的辅助诊断和手术计划操作,制定个体化的手术方案,并按照手术方案进行模拟手术操作。比较模拟手术与实际手术中解剖结构显示的异同,并将手术时间、出血量、并发症情况及预后等指标与未进行手术计划操作的对照组病例进行比较,研究虚拟现实手术计划系统能否提高手术水平、减小手术风险进而改善患者预后,评价虚拟现实技术在开颅夹闭颅内动脉瘤手术中的应用价值。材料与方法选择南京军区福州总医院神经外科2007年1月至2007年9月收治的颅内动脉瘤拟开颅手术患者106例作为研究对象,随机分为手术计划组和对照组。手术计划组51例中有21例因未行3D-CTA检查而剔除,剩余30例进行了术前计划操作;对照组56例,未进行术前计划操作。采用新加坡VI公司Dextroscope硬件系统,RadioDexter1.2软件系统。将每例病人原始容积扫描数据分别导入系统,经过必要的数据准备处理后加载到VR环境中,进行脑血管和颅骨的虚拟三维重建,显示颅内血管及颅骨图像。利用系统工具进行缩放、测量、分离、融合等操作,清晰显示动脉瘤及其与载瘤动脉和周围结构的关系。利用血管内窥镜工具观察动脉瘤与载瘤动脉内有无钙化和分隔,观察瘤颈各剖面的形状。完成对解剖结构的观测后,进行术前评估和手术计划,手术计划包括入路、体位、重要步骤、应急处理预案等具体方案。之后再按照手术计划进行模拟手术。实际手术尽量按照已制定的手术方案进行,观察术中所见与模拟手术所见是否相同,记录两组病例手术时间、动脉瘤术中破裂例数、手术出血量、并发症情况等指标进行对比。手术后3个月进行随访,以格拉斯哥预后量表评分为标准判断预后。统计学分析采用SPSS 13.0统计软件,计量资料以均数±标准差(Mean±SD)表示,方法采用两样本t检验;计数资料采用卡方检验;等级资料采用秩和检验,各种检验方法均以P＜0.05示差异有统计学意义。研究结果在虚拟现实状态下能够清晰和直观地观察动脉瘤的部位、大小、形态、动脉瘤及瘤颈与载瘤动脉和前后床突等骨性标志的关系。在虚拟现实状态下可对动脉瘤大小、形状、瘤囊方向、与重要解剖标志的位置关系等影像数据进行准确的测量。对每例患者都进行了术前评估并成功地制定了个体化的手术计划,并依照手术计划进行开颅、显露等模拟手术操作。手术计划组按照术前制定的方案进行手术,手术所见与模拟手术所见一致。与对照组相比,手术计划组术中动脉瘤破裂比例较小,出血量、手术时间和术后住院天数也小于对照组。统计学分析结果显示,两组病例手术出血量、手术时间的差异有统计学意义,术中动脉瘤破裂发生率、平均住院日无显著性差异。患者出院时统计并发症出现情况,结果显示手术计划组并发症发生率低于对照组,但两组差异无显著性。手术计划组预后良好率高于对照组,但统计结果显示两组的差异无显著性意义。研究结论1、利用虚拟现实手术计划系统可对颅内动脉瘤患者进行三维影像重建,在虚拟现实状态下能够清晰和直观地观察动脉瘤及其毗邻结构,据此可进行术前评估和手术计划的制定,并可按照手术计划进行接近实际手术状态的模拟手术操作和演示,使手术者提前了解术中可能出现的情况。2、通过虚拟现实手术计划系统的观测而制定的手术计划切实可行,实际手术中所见的解剖关系与术前虚拟现实状态的观察高度一致,模拟手术能够为实际手术提供指导和帮助。3、虚拟现实手术计划系统的应用,可减少颅内动脉瘤患者夹闭手术出血量,缩短手术时间,降低手术风险。第三章虚拟现实技术在颅底肿瘤手术计划中的应用研究目的通过对颅底肿瘤患者进行术前虚拟现实手术计划系统的辅助诊断和手术计划操作,制定个体化的手术方案,并进行模拟手术操作。比较模拟手术与实际手术中解剖结构显示的异同,研究虚拟现实手术计划系统能否提高手术质量、缩短手术时间、减小手术风险进而改善患者预后,评价虚拟现实技术在颅底肿瘤手术中的应用价值。材料与方法选择南京军区福州总医院2007年6月至2007年9月收治的颅底肿瘤患者39例,其中手术计划组19例,对照组20例。手术计划组患者术前利用Dextroscope系统进行虚拟现实状态下的三维重建,显示肿瘤与颅内重要结构的关系,观察肿瘤各剖面的形状和毗邻结构,详细记录重要解剖数据。据此进行术前评估,制定手术方案,按照制定的手术方案进行模拟手术,再根据模拟手术情况对手术方案进一步进行修正。观察术中所见与模拟手术所见是否一致,验证手术计划是否合适。记录两组手术时间、肿瘤切除程度、出血量等指标。术后复查CT或MR,了解肿瘤切除程度。出院时记录患者并发症情况,统计两组住院时间、ICU时间、住院医疗费。比较两组手术出血量、手术时间、肿瘤切除程度、并发症、ICU时间、住院时间及住院医疗费等指标的差异。统计学分析采用SPSS 13.0统计软件,计量资料以均数±标准差(Mean±SD)表示,方法采用两样本t检验;计数资料采用卡方检验。各种检验方法均以P＜0.05示差异有统计学意义。研究结果19例手术计划组患者均进行了虚拟现实状态下的三维影像重建等系列操作。重建后的不同结构的图像可根据需要随意组合显示。系统可对虚拟图像进行任意角度的旋转和切割,可进行任意切面的观察和测量,利用透明化的方法可以显示更多解剖学信息。系统工具还可进行分离、测量、着色、缩放等多种操作,最终可非常直观地显示肿瘤的位置、大小及其与血管、神经、颅骨等重要结构的解剖关系。每例患者都进行了术前评估,制定了包括体位、头部屈伸旋转的角度、手术入路、皮肤切口、颅骨钻孔位置、骨瓣大小、硬膜切口、肿瘤的显露方法、肿瘤切除程度以及术中应急预案等内容的手术计划。依照手术计划进行开颅、显露和切除肿瘤等模拟手术操作。全部病例按照模拟手术方案进行手术,实际手术情况与模拟手术所见完全吻合。手术过程均顺利,入路和显露均满意。手术效果良好,无死亡病例。与对照组相比,手术计划组平均手术时间明显缩短,手术出血量有所减少,统计分析表明差异有显著性。手术计划组的肿瘤全切除率高于对照组,但差异无显著性。手术计划组并发症发生率低于对照组,但两组差异无显著性。手术计划组患者手术后ICU天数、术后住院天数均小于对照组,住院总医疗费也明显少于对照组。但统计学分析显示差异无显著性。研究结论1、利用虚拟现实手术计划系统可对颅底瘤患者进行三维影像重建,该系统形成的三维立体虚拟影像清晰、逼真,可非常直观地显示肿瘤的位置、大小及其与血管、神经、颅骨的解剖关系,能使术者获得更丰富的立体解剖信息。据此可进行术前评估和手术计划的制定,并可进行模拟手术操作和演示,为选择最佳手术方案提供依据。2、通过虚拟现实手术计划系统的观测而制定的手术计划切实可行,实际手术中所见的解剖关系与术前虚拟现实状态的观察高度一致,模拟手术能够为实际手术提供指导和帮助。3、虚拟现实手术计划系统的应用,可减少颅底肿瘤患者手术出血量,缩短手术时间,降低手术风险。4、虚拟现实手术计划系统的应用并未增加患者的医疗费负担。更多还原

【Abstract】 BackgroundNeurosurgery is one of the most difficult and the finest surgical operations. The microneurosurgery plays the significant role in the neurosurgery department of 21st century. Choosing the best operative approach according to the patient’s condition and carrying out the individual operation are necessary for the neurosurgeon. For the development of the neurosurgery, it is essential to carry out accurate, direct-viewing, the individual operation plan and the mimic surgery.The surgical plan system based on virtual reality(VR)image is an advanced medical imaging system which employs CT or MR data to produce a kind of three-dimensional (3D) VR environment, which could be randomly rotated, dragged, assisted with cutting isolated and fused etc. Mimic operation could be performed using different tools, which could reveal clearly the operation area and anatomic structure directly.The surgical plan system based on VR image has prevailed in the neurosurgical centers of some developed countries, but is still at its infant stage in China. To investigate the clinical practice of Dextroscope system used in the neurosurgery department, we choose ruptured intracranial aneurysms and skull base tumor as the main goal, especially to evaluate the value of virtual reality techniques in diagnosing aneurysms, and the treatment of craniotomy clipping of intracranial aneurysm and the skull base tumors.Whether this system enhances the diagnosis rate, raise the neurosurgery level, reduce complication and the mortality is our issue. We also assess the feasibility in the application of clinical practice.Chapter 1 virtual reality techniques in diagnosingthe intracranial aneurysm at the early stageIntroduction about the Dextroscope systemDextroscope system is one of surgery plan systems based on virtual reality techniques, designed by the company of Singapore VI(Volume Interactions). This system is composed of the Dextroscope hardware system and the RadioDexter software system.RadioDexter system is the combined application of virtual imaging techniques and three-dimensional computed tomographic angiography, which employs CT or MR data to produce a kind of three-dimensional (3D) VR environment. Surgeons may manipulate the 3D virtual medical images with their hands interactively and directly. RadioDexter can slice the image that enables surgeon to have a clear understanding about surgery region with various part of structure.We compared the virtual reality techniques with the DSA examination to explore its advantage and disadvantage in the diagnosis of ruptured intracranial aneurysms.Objective The purpose of this study was to evaluate the clinical value of using 3D-CTA combined with the RadioDexter plan system based on VR image to screen and diagnose ruptured intracranial aneurysms. Compared with the DSA examination, we explore the clinical value of the virtual reality techniques in diagnose of ruptured intracranial aneurysms at the early stage.Materials and MethodsA total of 80 SAH patients was treated in Zhujinag hospital of Southern Medical University during December 2005 and December 2006. All the patients received 3D-CTA and Dextroscope examinations, and then DSA examination. The patients with negative results received the examination for a second time one month later, to evaluate the clinical value of using 3D-CTA combined with VR on the diagnosis of the intracranial aneurysms.ResultsA total of 73 aneurysms were detected in 68 of the 80 cases by 3D-CTA and Dextroscope examination. Among the 68 patients, there were 2 patients with arteriovenous malformation(AVM), 4 patients with multiple cerebral aneurysms. Among the other 12 patients, 5 cases were diagnosed as AVM, 2 cases as moyamoya disease, and the rest 5 cases were detected without positive findings. 68 patients received DSA examination to detect no false positive case.5 cases also had no positive findings after DSA examination, but the 3D-CTA and Dextroscope examination on these cases one month later found 2 aneurysms in 2 cases, which were confirmed by the DSA examination. The other 3 cases detected to be free of aneurysms again showed negative results in the DSA examination. As for the 68 aneurysms definitely diagnosed, 3D-CTA showed their location, size and profile, especially their anatomic relation to the parent artery and adjacent structures well . The 3D virtual images produced by the virtual imaging system were clear and vivid, and could be randomly rotated, dragged, isolated and fused et al. The virtual intravascular endoscope could be applied to observe thrombosis, calcification and separation and so on in the inner wall of blood vessels and tumor cavity, and clearly exhibit the site of the aneurysm neck, provide applicable data for surgical operations. All the patients in this study had undergone DSA examination. At the same time, part of them received rotational 3D DSA. It also detected no false positive and no negative findings after 3D-CTA and Dextroscope examination. DSA could clearly show their location, size profile and parent artery. However, DSA could not show the anatomic relation between artery and skull. Compared with 3D-CTA and Dextroscope images, 3D- Reconstruction data were less clear, precise and vivid.The diagnosis results of 80 patients at the first time with 3D-CTA : sensitivity 97.1%(68/70), specificity 100%(10/10); comprehensive results of twice 3D-CTA diagnosis : sensitivity 100%(70/70), specificity 100%(10/10). The results were completely consistent with the DSA diagnosis.Conclusions1. As a kind of technology for diagnostic imaging developed in recent years, 3D-CTA has been winning more and more attention in diagnosing and treating intracranial aneurysms. It is not convenient, fast, inexpensive and almost noninvasive by application, so,3D-CTA is the first choice of imaging examination for ruptured intracranial aneurysms, especially the emergency operation, examinations of post -operation and follow-up.2. Compared with the conventional planar 3D images, 3D-CTA images could show the aneurysms and their adjacent blood vessels and skulls more clearly and directly. And observe thrombosis, calcification and separation and so on in the inner wall of blood vessels and tumor cavity, but the blood flow can not be detected by 3D-CTA. It cannot show the aneurysms affected by cerebral venous sinus.3. Dextroscope is easier than 3D-CTA to manipulate. 3D-CTA show their location, size and profile, especially their anatomic relation to the parent artery and adjacent structures well. The 3D virtual images produced by the virtual imaging system are clear and vivid, and could be randomly rotated, dragged, isolated and fused etc .Compared with 3D-CTA, it can clearly show the anatomic relation between artery and skull.4. The virtual intravascular endoscope could be applied to observe thrombosis, calcification and separation and so on in the inner wall of blood vessels and tumor cavity, and clearly exhibit the site of the aneurysm neck. The body of aneurysm, maybe provide the position of ruptured aneurysms.5. The Dextroscope system based on VR techniques elevates the accuracy of diagnosis. Dextroscope system can provide surgeon with unprecedented direct-viewing, accurate, the clear aneurism, the adjacent blood vessels and the osseous structure images, which provide useful information for endovascular treatment and craniotomy.Chapter 2 Virtual reality technology in the microsurgery of aneurysmsObjectiveTo study whether the Dextroscope virtual reality surgical plan system can improve the quality of surgery, reduce the risk and improve the prognosis, assess the clinical value of virtual reality technology in the craniototmy clipping of intracranial aneurysm.Materials and methods A total of 106 patients planning to receive craniotomy clipping of intracranial aneurysm were selected from Fuzhou General Hospital of Nanjing Military Area Command during January 2007 and September 2007. All the patients were diagnosed aneurism after 3D-CTA and (or) DSA examinations and were randomly divided into operation planning group(51 cases) and the control group(56 cases). Among the 51 cases of planning group, 21 cases were excluded because of without 3D-CTA examination, all of the other 30 cases received pre-operation planning and simulation operation.Virtual reality surgery system of Dextroscope hardware and RadioDexter1.2 software systems (VI, Singapore) were adopted. The raw data of volumetric 3D-CTA scan for all patients were imported into the above systems and then loaded into the VR environment to perform virtual 3D reconstruction of the brain blood vessels and skulls and reveal their images; different instruments provided by the operating system were included in zooming, measuring, isolating and splitting procedures to display the aneurysms and the anatomic relation to their parent arteries and adjacent structures; The virtual intravascular endoscope could be applied to observe thrombosis, calcification and separation and so on in the inner wall of blood vessels and tumor cavity, and clearly exhibit the site of the aneurysm neck, the body of aneurysms.After observing anatomic structure, surgical assessment and plan were conducted. The surgical plan includes the approach, the body posture, the important procedures, emergency preparation. Then, surgical planning was mapped out and virtual surgery was performed. The actual surgery should be taken according to the surgery plan as possible, recording the differences and the same points between actual surgery and mimic surgery. All patients’ Glasgow outcome scores (GOS) were analyzed at the third month to judge prognosis.Results3D-CTA images could show the aneurysms, the shape, the neck of aneurysms, the parent artery and skulls more clearly and directly. Precisely measure the size, shape, the cyst of aneurysms, and anatomic landmark. It formulates the preoperative assessment and individual surgical plan and allows the option of preoperative rehearsal according to the operation plan, such as craniotomy.The operation group performs the surgery according to preoperative plan. What we observe in the process of operation is the same with the simulated surgery. Compared with the control group, the proportion of the breakage aneurism, the volume of blood, the period of surgery and the hospital day was smaller. Statistics shows that volume of blood, and the period of surgery is significantly different between the two groups. Aneurysm breakage rate and the average days in hospital were non-significance. The complication rate of operation group was lower than that of control group .but differences between two groups were non-significant. The prognosis rate of surgery group was higher than that of control group, but differences between two groups were statistically non-significant.Conclusions:1. Using the VR operation system can conduct 3D reconstruction of the aneurysms. Which show the aneurysms and adjacent structures clearly and vivid. Formulate individual plan, perform the simulated operation according to the surgical plan, which can make the surgeon know what will happen in advance.2. The operation plan is available based on the VR operation system. What we observe in actual surgery is highly consist with preoperative rehearsal. The simulated operation can provide guidance and assistance in actual operation. 3. The application of virtual reality surgery system can improve the quality of surgery, reduce the risk and improve the prognosis, significantly improve the result of craniotomy clipping of intracranial aneurysm.Chapter 3 Virtual reality technology in microsurgery of skull base tumorsObjectiveFor the patients with skull base tumors using Dextroscope system to make auxiliary diagnosis and the operation, which help formulate individual plan, perform the simulated operation according to the surgical plan. Demonstrate the differences of anatomic structure between the simulated surgery and the actual surgery, and assess the clinical value of virtual reality technology for skull base tumors.Materials and methodsA total of 39 patients (operation group=19, surgical group=20 ) with the tumors of skull base were selected from Fuzhou General Hospital of Nanjing Military Area Command during June 2007 and September 2007. Use the Dextroscope system to conduct 3D reconstruction in VR environment, which can show the relationship between tumors and other important structures. Observe the shape and adjacent structures of the tumor, and then carefully record the important anatomical data. Operation program was conducted based on the preoperative assessment to perform the stimulated surgery. It is necessary to rectify the operation plan if it changes. Differences between simulated surgery and actual condition should be carefully observed, and to validate whether the program is appropriate. Extent of lesion-resection, volume of blood and the period of surgery also should be registered. Secondary CT or MR was necessary to get the information about the extent of tumor-resection. After that, complication situation, the period of staying in the hospital, the days in the ICU and all fees should be written down when the patientswere dismissed. The differences of those indexes were compared.ResultsThe 19 cases were adopted 3D-reconstruction in virtual reality environment. After the reconstruction, different structure’s images can combine each other at will. The system can also randomly carry those pictures to revolve or cut. Every section can be randomly observed. Different instruments provided by the operating system were included in zooming, measuring, isolating and splitting procedures to display the location of tumor, shape, nerve, blood vessels, and adjacent structures. Every patient underwent preoperative assessment, which includes the body posture, the flexion and extension, the operative approach, the skin incision, the drilling position, the size of bone flaps, the incision of dura mater, extent of lesion-resection and emergency plan in the process of operation et al. Operative procedures should be performed according to the simulated surgical plan. All the operation is same as preoperative plan. At the same time, approach, operation exposure were satisfied, and the results of all operations were good. Nobody died in the process of operation.Compared with the control group, the period of the operation, the volume of blood was smaller. Statistics showed that volume of blood, and the period of surgery was significantly different between the two groups. The complication rate of operation group was lower than that of control group, but differences between two groups were non-significant. Compared with control group, the length of stay and the days in the ICU were decreased, and all fees were lower in operation group, but the differences between the two groups were statistically non-significant.Conclusions1. Using the VR operation system can conduct 3D reconstruction of the skull base tumors, which show the location of tumor, shape, blood vessels, nerve and adjacent structures clearly and vivid. And demonstrate more 3D information for the surgeon. After formulating the preoperative assessment and individual plan, it is time to perform the simulated operation according to the surgical plan, which supplies best approach for surgeon in actual operation.2. The operation plan based on VR techniques is available. What we observe in actual surgery is highly consist with preoperative rehearsal. The simulated operation can provide guidance and assistance in actual operation.3. The application of virtual reality surgery system not only reduces the blood loss for the patients of skull base tumors, shorten the period of operation, but also can decrease the risk.4. The application of virtual reality surgery system has not increase the burden.更多还原