基于体积变化的四维计算机断层图像重建

背景：目前还没有国产的四维计算机断层图像(4D-CT)机,而进口4D-CT系统要求在图像采集过程中监测呼吸信号,因此4D-CT重建只局限于特定少数品牌的进口CT机。另外,呼吸监测装置及4D-CT重建软件价格高昂,限制了这一先进技术在国内的普及应用。 目的：克服现有4D-CT重建系统的缺陷,在普通多螺旋CT上实现4D-CT重建。 方法：采用VC++程序设计语言和VTK工具包,开发4D-CT图像重建软件系统。对自由呼吸的患者进行多床位电影模式(Cine模式)扫描,每个床位Cine扫描持续时间约为患者的1个呼吸周期加1 s(4~6 s),在这期间每排CT探测器重建出8~15幅不同时刻(相位)的CT图像。 结果与结论：根据体表轮廓和肺组织的体积变化确定CT图像在呼吸周期中的相位,并按相位不同对所有CT图像进行分组,得到一个完整的呼吸周期中多个相位的CT系列,再分别对各相CT图像序列进行三维(3D)重建,即得到了随时间变化的4D-CT系列,它不但明显地消除了运动伪影,而且反映了胸部和腹部脏器随呼吸运动变化的规律。提示基于体表轮廓和肺体积的周期性变化,能在普通螺旋CT上实现4D-CT重建,其重建过程不依赖于外在的呼吸监测装置、不受CT机本身的软硬件限制,具有普遍适用性。     

脑出血后出血病灶的CT三维重建模型

目的 为计算机辅助立体定向设备的研发设计的,可以依据CT扫描数据进行三维重建并模拟临床脑出血操作过程的颅骨模型.方法 以融解的石蜡灌铸内置有假想病灶的颅骨标本制为颅骨模型,采集CT扫描后的序列DICOM数据,通过自编软件平台进行3D重建、手术规划,由计算机辅助立体定向设备对该模型进行模拟微创穿刺.结果 完成蜡灌铸的脑出血颅骨模型,且该模型在CT扫描和之后的3D重建中可清晰显示和区别标记物、骨骼、石蜡、假想病灶.结论 蜡铸脑出血颅骨模型方法简单、可反复建模,能较理想地评估计算机辅助立体定向设备原型机的系统性能.     

Value of routine immediate postoperative brain computerized tomography in pediatric neurosurgical patients

Purpose  

Routine immediate postoperative brain CT (RIPO CT) has advantages and disadvantages. The present study was performed to know the extent of gain by RIPO CT in the aspect of immediate postoperative patient care in pediatric patient population and according to the disease entity and surgical procedure.     

Two cases of primary osteolytic intraosseous meningioma of the skull metastasizing to whole skull and the spine

We report here two cases of primary intraosseous meningioma with aggressive behavior. A 68-year-old man presented with a one year history of a soft, enlarging mass in the right parietal region. Magnetic resonance image (MRI) revealed a 6 cm sized, heterogeneously-enhancing, bony expansile mass in the right parietal bone, and computed tomograph (CT) showed a bony, destructive lesion. The tumor, including the surrounding normal bone, was totally resected. Dural invasion was not apparent. Diagnosis was atypical meningioma, which extensively metastasized within the skull one year later. A 74-year-old woman presented with a 5-month history of a soft mass on the left frontal area. MRI revealed a 4 cm sized, multilobulated, strongly-enhancing lesion on the left frontal bone, and CT showed a destructive lesion. The mass was adhered tightly to the scalp and dura mater. The lesion was totally removed. Biopsy showed a papillary meningioma. The patient refused adjuvant radiation therapy and later underwent two reoperations for recurred lesions, at 19 and at 45 months postoperative. The patient experienced back pain 5 years later, and MRI showed an osteolytic lesion on the 11th thoracic vertebra. After her operation, a metastatic papillary meningioma was diagnosed. These osteolytic intraosseous meningiomas had atypical/malignant pathologies, which metastasized to whole skull and the spine.     

Body computerized tomography and the thymus.

Preoperative body computerized tomography (CT) should be of value in depicting the size, extent, and location(s) of the thymus in myasthenic patients undergoing thymectomy. To date, we have been unable to visualize the thymus in three patients with myasthenia gravis using body CT. However, in two nonmyasthenic patients, large thymomas were clearly delineated. Although application of this technique currently appears limited by the size, location, and density of the thymus and the resolution of the scanners, we feel that CT of the mediastinum is an indicated procedure in the evaluation of the patient before thymectomy, especially in those myasthenic patients with a high risk of thymoma.     

3D—CTA、3D—DSA对颅内动脉瘤临床诊断价值的对比

目的探讨三维CT血管造影术（3D-CTA）在颅内动脉瘤诊断中的应用价值。方法采用3D-CTA检查疑似颅内动脉瘤患者62例。根据3D-CTA结果决定直接手术者51例,进一步行三维数字减影全脑血管造影（3D-DSA）检查11例（5例诊断为颅内动脉瘤者接受了手术治疗）。术后复查3D-DSA56例。结果62例患者中,6例经3D-CTA及3D-DSA检查均未发现动脉瘤,56例依3D-DSA检查及手术所见,共发现68个颅内动脉瘤。3D-CTA在显示动脉瘤大小及形态方面与术中所见及3D-DSA检查发现相类似。3D-CTA和3D-DSA测得的颅内动脉瘤瘤体纵径、颈宽等均差异不显著（P0.05）。结论尽管3D-DSA目前仍然是诊断颅内动脉瘤的金标准,但3D-CTA也是诊治颅内动脉瘤的一种快捷、安全、操作简便的方法,亦可为制定手术方案提供详细的资料。     

Our method of projecting onto the skull surface the intracranial lesions diagnosed by computerized tomography

The author presents an own method for the projection onto the surface of the skull of intracranial lesions demonstrated by means of computerized tomography. The method makes possible a more precise and sparing craniotomy and calculation of the irradiation field in case of radiotherapy. The advantage of the method is its easy availability and independence of computerized calculations. It may be applied only to CT images.     

医学图像的三维重建及基于VTK的实现和应用

背景：VTK是一个免费的图像三维重建和处理的专业开发平台,其功能强大,源代码开放,用户可以根据自己的需求灵活的定制和开发。 目的：介绍图像三维可视化中常用的面绘制和体绘制两类可视化技术的原理,以及其典型的Marching Cubes和Ray Casting三维重建算法,并对重建的三维医学图像的应用和扩展进行了探讨。 方法：基于免费的VTK可视化开发包平台和Visual C++ 6.0 IDE开发工具,使用C++语言,采用真实人体CT数据集,实现CT图像的三维重建和应用扩展。 结果与结论：基于VTK平台,采用面绘制和体绘制不同绘制原理实现了医学图像的三维可视化。重建得到的三维医学图像,显示效果清晰直观,并且可以配合进行三维医学图像的测量、虚拟切割等操作,取得了较好的效果。     

适用于立体定向设备的颅骨模型制作及其CT图像重建

目的为计算机辅助立体定向设备的研发，设计可以依据CT扫描数据进行三维重建并模拟临床脑出血微创操作过程的颅骨模型。方法以融解的石蜡灌铸内置有假想病灶的颅骨标本制为颅骨模型，采集CT数据，通过自编软件平台进行3D重建。结果完成蜡灌铸的脑出血颅骨模型，且该模型在扫描和重建中可清晰地显示和区别标记物、骨骼、石蜡、假想病灶。结论蜡铸脑出血颅骨模型方法简易、低廉、可重复，能较理想地评估计算机辅助立体定向设备原型机的系统性能。     

Three-dimensional reconstruction of bovine intradural spinal root myelin by electron microscope tomography.

Electron microscope tomography was used to reconstruct three-dimensionally the configuration of heavy metal staining in bovine intradural spinal root myelin. Samples were fixed with glutaraldehyde, exposed to osmium tetroxide, embedded, thin sectioned, and finally stained with uranyl-acetate and lead citrate. Reconstructions up to 4.2 nm resolution showed a non-uniform distribution of stain in the planes of individual cytoplasmic appositions (major dense lines). In each reconstructed major dense line the stain was distributed in striated, well-defined structures. Those structures appear to be nearly parallel between neighboring major dense lines. The distribution of stain in the Schmidt-Lanterman cleft did not resemble the distribution of stain in the major dense line; however, weak striations were present. Evidence that the striated structures are not an artifact due to image calculation is discussed.     

64排螺旋CT三维重建在肾脏移植中的价值

背景：目前应用相对无创的多排螺旋CT来替代有创的数字减影血管造影进行评价肾脏移植手术中肾脏解剖及功能情况,主要集中在16排螺旋CT及以下机型,鲜有关于64排螺旋CT应用在肾脏移植中的报道。 目的：探讨64排螺旋CT三维重建技术在肾脏移植手术中供者肾脏及受者肾脏的检查价值。 方法：对7例拟自愿捐献一侧肾脏给其亲属进行活体肾脏移植的供者肾脏及6例接受了肾脏移植的受者肾脏进行了CT平扫、动脉期、静脉期及延迟期增强扫描,并对增强扫描各期进行多平面重建、容积再现技术、最大密度投影及曲面重建等三维后处理。 结果与结论：7例供者CT血管造影显示左右肾均为1条肾动脉者4例;左肾2条肾动脉,右肾1条肾动脉者1例;左肾3条肾动脉,右肾两条肾动脉者2例;所有供者左右肾均见1条肾静脉及1套肾盂输尿管。MPR重建显示左肾囊肿1例,CT尿路造影显示双肾功能均未见异常,与手术对照,符合率100%。6例受者中CT血管造影显示6例移植肾动脉、静脉及输尿管吻合口均未见狭窄及内瘘,其中4例移植肾大小形态及密度正常,增强扫描动脉期皮质髓质分界清晰,皮质CT值均在150 HU以上,静脉期肾脏实质强化均匀,CT尿路造影显示肾脏泌尿功能正常;2例移植肾增强扫描动脉期皮质髓质分界不清,皮质CT值均小于100 HU,静脉期肾脏实质强化较弱,延迟10 min扫描仅见少量对比剂排泄,经过肾脏穿刺确诊为排斥反应。结果表明,64排螺旋CT三维重建技术能完成对肾实质、肾血管以及泌尿系统的综合评价,可作为肾脏移植前后评价肾脏解剖及功能的较好方法。 关键词：体层摄影术,X射线计算机;后处理;肾移植;三维重建;排斥     

Use of computerized tomography in senile dementia.

Computerized tomography was used to evaluate 35 patients with senile dementia and proved to be a simple and practical screening procedure. Those patients with moderate or severe cerebral atrophy had a poorer short-term prognosis than those with questionable or mild atrophy. Two patients with potentially treatable illnesses (hypothyroidism and pernicious anaemia) and only questionable atrophy had reversal of the dementia with treatment. A single patient with moderate atrophy had a potentially treatable illness (hypothyroidism) which only partially resolved. Those patients with dementia but relatively little atrophy by computerized tomography may represent a unique group with a better prognosis who require particularly careful evaluation for potentially treatable illnesses.     

基于通用CAD技术的三维假牙模型重建

背景：由于全口假牙没有牙齿作为牙托的支撑,压力全部到牙龈上面,假牙活动咀嚼食物时不可避免对作为牙托支撑的牙龈进行磨损,患者也经常出现牙龈发炎和假牙托的金属过敏症状,因此为患者安装假牙前,医生必须先测试其对假牙材料的适应性。 目的：对经历磨合期后的假牙进行三维模型重建。 方法：使用激光扫描仪等数字采集设备采集了经过磨合期的全口假牙三维数据,利用逆向软件进行减少噪声点、数据滤波、数据精简及对缺失的数据进行修补等预处理并封装为三角曲面,通过Pro/E等三维设计软件实现模型的重建。 结果与结论：通过激光扫描仪、CT等数字采集设备采集经过磨合期的全口假牙三维数据,利用逆向软件对采集到的数据进行预处理包括减少噪声点、数据精简、数据滤波及对缺失的数据进行修补等并提取曲线模型,最后在Pro/E等三维设计软件中实现了模型重建。重建的模型可为假牙的制作提供数字信息,也可以通过快速成型得到假牙的复制品。逆向重建的经过磨合期的全口假牙,不仅节约了时间,减少医生的劳动强度,还降低患者对材料过敏的风险,缩短患者与假牙的磨合期,减少患者的痛苦。     

High resolution computerized tomography with coronal and sagittal reconstruction in the diagnosis of brain tumors in children

We present 4 children with brain tumors that were missed or incompletely characterized conventional computerized tomography (CT) scanning. Using high resolution CT with high dose contrast and three-dimensional reconstruction, we were able to define the anatomy of each tumor and its associated aberrant vasculature. High resolution CT scanning with reconstruction is very helpful in diagnostic problems in which conventional CT scanning fails to provide a clear diagnosis.     

网络环境下人体器官的三维重建及变形仿真

背景：利用何种模型何种算法对不同器官组织进行变形仿真,既可保证逼真性又可兼顾实时性,目前的设计都是在单机系统上实现。目的：为了实现基于网络的人体器官的变形仿真及交互,设计以人体器官肾脏为例,利用CT图像,在VRML平台上实现器官模型的三维重建。方法：利用质点弹簧模型建立肾脏的物理模型,实现变形计算。最后通过VRML外部编程接口EAI和Java-Applet进行通信,实现器官模型在任意位置、任意外力作用下的变形模拟。结果与结论：在CT图像的基础上实现了人体器官肾脏的三维重建,并利用质点弹簧模型实现了人体器官肾脏的变形模拟。借助于JAVA和VRML的结合,实现了网络环境下肾脏的变形仿真,用户只需在网页界面中输入作用力的大小和作用位置点的序列,即可得到肾脏变形情况的场景。研究虽仅以简单的拉伸和挤压变形为例,其他变形亦可通过类似的方法实现。实验为人体器官的变形和虚拟手术系统的网络交互功能的实现提供了一种思路。     

The aid of computerized tomography in hemifacial spasm.

Although the physiopathological mechanisms causing hemifacial spasm are not clearly understood, it is generally accepted that the causative factor is compression of the facial nerve at its root exit zone. In this paper we present seven cases of hemifacial spasm which were studied by dynamic CT scanning in the preoperative period, and treated with microvascular decompression. We suggest that CT scanning has considerable diagnostic value in disclosing the asymmetrical vascular formation causing root exit zone compression and that microvascular decompression should be the treatment of choice in this condition.     

Benign metastasizing leiomyoma to skull base and spine: a report of two cases

OBJECTIVE AND IMPORTANCE: We report two patients with benign uterine leiomyoma metastasizing to the nervous system, respectively, to the skull base and to the spine. Although primary cranial and metastatic spinal leiomyomas have been rarely described, to our knowledge no case of benign leiomyoma metastasizing to the skull base has been reported before. CLINICAL PRESENTATION: Two female patients with history of hysterectomy for benign leiomyoma, subsequently metastasizing to the lungs and smooth muscles of the skin, presented with a focal neurologic deficit. Magnetic resonance imaging revealed a sacral mass in one case and a skull base tumor in the other. INTERVENTION: Both patients underwent surgery for resection of the lesions. Good postoperative results were obtained. Histologic examination of the surgical specimen revealed a benign metastasizing leiomyoma. CONCLUSION: Benign metastasizing leiomyoma should be considered in the differential diagnosis of mass lesions in the sacral spine and skull base in patients who have a history of uterine leiomyoma or benign metastases of the same disease in organs outside the nervous system.