数字技术在人工全髋关节置换术中的应用研究

目的探索把数字技术应用于人工全髋关节置换术,为临床选择更适配的人工全髋关节假体提供新的方法。方法6例成人病变的髋关节和42-56号的髋臼假体和01-04号钛合金股骨柄(矩形,HA微孔)假体连续CT扫描,将CT扫描数据经Mimics软件处理,3D计算建立髋关节和假体的数字模型。将数据输入SPSS 17.0进行统计学分析。根据术前选择的假体施行手术,术后6个月根据Harris评分进行评价,并与同期6例行传统人工全髋关节置换术患者髋关节Harris评分进行统计学比较。结果 6例骨盆三维模型数据测量结果分析:髋臼前倾角、外展角与身高、性别、侧别因素无显著性差异;股骨颈前倾角及颈干角与侧别、性别及身高因素无统计学差异。结论数字技术可以指导选择更匹配的全髋关节假体,提高人工全髋关节置换术的近期效果,为临床术前选择全髋关节假体提供一种新的方法。     

医学图像三维可视化系统在胰腺及壶腹周围肿瘤可切除性评估中的应用

Pancreatic cancer is malignant with a poor prognosis,and its incidence is rising worldwide in recent years.Multiple slices spiral computed tomography and computed angiography are the first choice for t...     

New Statistical Method to Analyze Three-Dimensional Landmark Configurations Obtained with Cone-Beam CT: Basic Features and Clinical Application for Rapid Maxillary Expansion

Objective

To describe a statistical method of three-dimensional landmark configuration data and apply it to an orthodontic data set comparing two types of rapid maxillary expansion (RME) treatments.

Materials and Methods

Landmark configurations obtained from cone beam CT scans were used to represent patients in two types (please describe what were two types) of RME groups and a control group over four time points. A method using tools from persistent homology and dimensionality reduction is presented and used to identify variability between the subjects.

Results

The analysis was in agreement with previous results using conventional methods, which found significant differences between treatment groups and the control, but no distinction between the types of treatment. Additionally, it was found that second molar eruption varied considerably between the subjects, and this has not been evaluated in previous analyses.

Conclusion

This method of analysis allows entire configurations to be considered as a whole, and does not require specific inter-landmark distances or angles to be selected. Sources of variability present themselves, without having to be individually sought after. This method is suggested as an additional tool for the analysis of landmark configuration data.     

Three-dimensional sonographic volume measurement of the fetal stomach

The objective of this study was to measure the fetal gastric volume using three-dimensional (3-D) ultrasound during pregnancy. Three-dimensional sonographic examinations were performed involving 35 pregnant women from 12 to 38 weeks of gestation. The fetal gastric volume was monitored every 5 min for a minimum of 40 min (40-60 min) in each woman. The rotational technique with Virtual Organ Computer-aided AnaLysis (VOCAL) was used to calculate the fetal gastric volume. Maximum and minimum gastric volumes were curvilinearly associated with the gestational age, respectively (R(2) = 0.611, p < 0.0001, and R(2) = 0.407, p < 0.0001, respectively). A curvilinear relationship was noted between the functional capacity (maximum volume - minimum volume) of the fetal stomach and gestational age (R(2) = 0.531, p < 0.0001). The maximum volume change [(maximum volume - minimum volume/maximum volume) × 100] did not change during pregnancy (mean and standard deviation, 64.1% ± 16.1%). However, gastric emptying cycles could not be determined in this study because of the short observation period and small number of subjects. Our findings suggest that the fetal gastric volume calculated by conventional two-dimensional ultrasound in previous investigations is approximately one-third of the maximum volume using 3-D ultrasound in the present study and that 3-D ultrasound is a superior means of evaluating the fetal gastric volume in utero. However, the data and their interpretation in the present study should be viewed with some degree of caution because of the small number of subjects. Further studies involving a larger sample size are needed to confirm these findings.     

Corneal structure and transparency

The corneal stroma plays several pivotal roles within the eye. Optically, it is the main refracting lens and thus has to combine almost perfect transmission of visible light with precise shape, in order to focus incoming light. Furthermore, mechanically it has to be extremely tough to protect the inner contents of the eye. These functions are governed by its structure at all hierarchical levels. The basic principles of corneal structure and transparency have been known for some time, but in recent years X-ray scattering and other methods have revealed that the details of this structure are far more complex than previously thought and that the intricacy of the arrangement of the collagenous lamellae provides the shape and the mechanical properties of the tissue. At the molecular level, modern technologies and theoretical modelling have started to explain exactly how the collagen fibrils are arranged within the stromal lamellae and how proteoglycans maintain this ultrastructure. In this review we describe the current state of knowledge about the three-dimensional stromal architecture at the microscopic level, and about the control mechanisms at the nanoscopic level that lead to optical transparency.     

数字断层融合技术在舟状骨隐匿性骨折诊断中的应用

目的:探讨X射线数字断层融合技术(DTS)在舟状骨隐匿性骨折中的应用价值。方法:前瞻性地选择19例数字X射线摄影(DR)舟状骨骨折不明显或怀疑舟状骨骨折的患者行DTS检查。对其中7例患者行CT三维重建,观察对比各种方法的图像质量及诊断结果。结果:19例患者经DTS检查,其中17例可明显显示舟状骨骨折征象,排除2例疑似病例。7例CT三维重建均显示骨折。结论:X射线数字断层融合技术图像质量明显高于DR摄影,可以较好的显示隐匿性骨折;且具有辐射剂量低、价格低廉、图像成像清晰以及诊断准确率较高等优势,其显示的骨骼解剖结构空间位置比CT更直观,能够得到更多骨骼细节信息,是CT、MRI检查的重要延伸和补充,值得推广应用。     

人体胸廓三维有限元模型的建立过程和应力分布特点

目的：探讨人体胸廓三维有限元模型的建立过程和应力分布特点,以证实三维有限元模型的可靠性,为心肺脑复苏急救时胸外按压机制和效果提供生物力学依据。方法胸部多层螺旋CT扫描辅助下成功建立人体胸廓三维有限元男女模型各一个,模拟垂直胸外按压,分析人体胸廓三维有限元模型的各部位胸廓位移和应力特点。结果成功建立脊柱、锁骨、肋骨和胸骨等胸廓结构的三维有限元模型,男/女共741006/760816个节点,男/女共316034/326785个单位。参照CT影像学特点将人体胸廓三维有限元模型分为6种材料性质。模拟垂直胸外按压,向下移位最大的胸廓部位为胸骨,应力主要分布于肋骨最后部位。静态加载时,胸骨位移恒定情况下,男性所需外力明显大于女性,两者比较差异具有统计学意义(P<0.05)。胸骨第4、5肋间、第5、6肋间达到相同位移时需要较小的外力,与胸骨3、4肋间比较差异具有统计学意义(P<0.05)。动态加载达到相同位移时所需外力较静态加载大,且随着频率增大,胸廓实际所承受的载荷逐渐减小,在80~100次/min时,相同外力作用下胸骨位移增加,但在110次/min时胸骨位移下降。结论建立人体胸廓三维有限元模型需提供精准的胸廓组织结构信息,为人体胸廓体外按压提供生物力学依据。     

三维多孔支架材料PLLA/n-HA的体外生物相容性研究

目的：研究三维多孔支架材料聚乳酸/纳米羟基磷灰石(PLLA/n-HA)的体外生物相容性,探讨其作为细胞培养材料和骨组织工程支架的可行性。方法将大鼠成骨细胞接种于PLLA/n-HA复合支架上,体外共同培养后,CCK-8法检测大鼠成骨细胞增殖活性,荧光倒置显微镜、扫描电子显微镜下观察PLLA/n-HA复合支架材料表面和孔隙内细胞粘附情况。结果 CCK-8法检测显示实验组复合支架材料上细胞的增殖与空白对照组的差异无统计学意义（P>0.05）;电镜观察到细胞在复合支架材料表面和孔隙内大量黏附、生长,并且随着共培养时间的增加,材料表面的细胞数量呈几何级增长。结论三维多孔支架材料PLLA/n-HA的生物相容性较好,可望成为一种性能良好的骨组织工程支架材料。     

Three-dimensional laparoscopy and thoracoscopy in children and adults: A prospective clinical trial

Background: Laparoscopic procedures for children and adults already provide many advantages in two-dimensional (2D) vision. Only limited experiences exist for laparoscopic three-dimensional (3D) procedures in vivo. The aim of this prospective trial was to identify indications and limitations of the 3D-system in laparoscopic minimally invasive procedures in children and adults. Material and methods: In a prospective quality assurance for laparoscopic 3D evaluation in children and adults, a total of 53 consecutive patients (22 children, 31 adults) were included. Laparoscopic transabdominal, retroperitoneal and thoracoscopic procedures were performed. For laparoscopic 3D imaging a Camera Control Unit (CCU), 3D monitor and 3D-TIPCAM® were used. Patient data, operative procedures and image quality of the 3D system were assessed. Results: Of 53 patients, 22/53 were children and 31/53 adults with a mean age of 7.6 years (range, 10 months to 15 years) and 51.5 years (range, 18 to 79 years), respectively. 8/22 children were two years old or younger. No relevant difficulties occurred with nausea, fatigue, vertigo, eye blurring or double vision, burning eyes, visual fatigue, inconvenience of visual adaptation of 3D to 2D, or medical discomforts for the surgeons in both children and adults. Difficulties were mainly addressed to the small distance of the video endoscope and the organ tissue in small children and affected mainly image definition, resolution and eye focusing. Conclusions: Advantages of 3D over 2D were mainly considered to be of relevant benefit in adults. Subjective advantages were seen in children and adults for stereoscopic depth perception, better visualization of anatomical structures and understanding of the anatomy, as well as for complex maneuvers such as suturing.