Dissertations / Theses on the topic 'Surgical simulation systems'

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; in conjunction with the Leaders for Global Operations Program at MIT, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 79).
Massachusetts General Hospital (MGH) is currently the nation's top ranked hospital and is the largest in New England. With over 900 hospital beds and approximately 38,000 operations performed each year, MGH's operating rooms (ORs) run at 90% utilization and their hospital beds at 99% operational occupancy. MGH is faced with capacity constraints throughout the perioperative (pre-, intra-, and postoperative) process and desires to improve throughput and decrease patient waiting time without adding expensive additional resources. This project focuses on matching the intraday scheduling of elective surgeries with the discharge rate and pattern of patients from the hospital floor by investigating ways surgeons could potentially schedule their cases within a given OR block. To do this, various scheduling rules are modeled to measure the impact of shifting patient flow in each step of the perioperative process. Currently the hospital floor proves to be the biggest bottleneck in the system. Delays in discharging patients result in Same Day Admits (patients that will be admitted to the hospital post-surgery) waiting for hospital beds in the Post Anesthesia Care Unit (PACU). These patients wait more than sixty minutes on average after being medically cleared to depart the PACU. A simulation model is built to evaluate the downstream effects of each scheduling rule and discharge process change. The model takes into account physical and staff resource limitations at each of the upstream and downstream steps in the perioperative process. By scheduling Same Day Admits last in each OR block, patient wait time in the PACU can be reduced up to 49%. By implementing the recommended changes the system will realize lower wait times for patients, less stress on the admitting and nursing staff, and a better overall use of the limited physical resources at MGH.
by Ashleigh Royalty Range.
S.M.
M.B.A.

In this dissertation, the accuracy and reliability of non-linear finite element computations in application to surgical simulation is evaluated. The evaluation is performed through comparison between the experiment and finite element analysis of indentation of soft tissue phantom and human brain phantom. The evaluation is done in terms of the forces acting on the cylindrical Aluminium indenter and deformation of the phantoms due to these forces. The deformation of the phantoms is measured by tracking 3D motions of X-ray opaque markers implanted in the direct neighbourhood under the indenter using a custom-made biplane X-ray image intensifiers (XRII) system. The phantoms are made of Sylgard® 527 gel to simulate the hyperelastic constitutive behaviour of the brain tissue. The phantoms are prepared layer by layer to facilitate the implantation of the X-ray opaque markers. The modelling of soft tissue phantom indentation and human brain phantom indentation is performed using the ABAQUSTM/Standard finite element solver. Realistic geometry model of the human brain phantom obtained from Magnetic Resonance images is used. Specific constitutive properties of the phantom layers determined through uniaxial compression tests are used in the model. The models accurately predict the indentation force-displacement relations and marker displacements in both soft tissue phantom indentation and human brain phantom indentation. Good agreement between the experimental and modelling results verifies the reliability and accuracy of the finite element analysis techniques used in this study and confirms the predictive power of these techniques in application to surgical simulation.

La chirurgie sans cicatrices, visant à réaliser des opérations chirurgicales sans cicatrices visibles, est l'avant-garde dans le domaine de la chirurgie mini-invasive. L'absence d'instruments adéquats est l'un des freins à son utilisation en routine clinique. Dans ce contexte, nous introduisons un nouveau robot chirurgical téléopéré, composé d'un endoscope et de deux instruments flexibles, avec 10 DDL motorisés. Cette thèse explore les différentes façons de contrôler le système. La cinématique du robot est analysée et différentes stratégies de contrôle maître/esclave, allant du contrôle articulaire au Cartésien, sont proposées. Ces stratégies ont été testés sur un simulateur virtuel ainsi que sur le système réel en laboratoire et en ex-vivo. Les résultats montrent qu’un seul utilisateur est capable de contrôler le robot et d’effectuer des tâches complexes en utilisant deux interfaces haptiques
No-scar surgery, which aims at performing surgical operations without visible scars, is the vanguard in the field of Minimally Invasive Surgery (MIS). The lack of adequate instrumentation is one of the issues to its clinical routine use. In this context, we introduce a novel teleoperated surgical robot, consisting of an endoscope and two flexible instruments, with 10 motorized DOFs. This thesis investigates the possibilities to control the system. The robot kinematics is analyzed, and differentmaster/slave control strategies, ranging from joint to Cartesian control, are proposed. These strategies have been tested on a specifically developed virtual simulator and on the real system in laboratory and ex-vivo experiments. The results show that a single user is capable to control the robotic system and to perform complex tasks by means of two haptic interfaces

As a good and competent surgical simulator, it should provide surgeons with visual, tactile and behavioral illusion of reality. In literature, methods for object deformation range from non-physically based models to physically based models. Early works of non-physically based models focused on pure geometrical models that were originally employed in computer-aided design. These methods could be used to produce vivid deformable effects in computer animation. However, the soft tissue simulation in surgical applications requires more realistic models based on physical properties of human tissues. As a result, the mass-spring model and the finite element model have become the most popular representations for deformable organs in surgical simulation. Our research focuses on the real-time soft tissue deformable model based on the finite element method for surgical application.
Extended from the hybrid condensed finite element model, an interactive hybrid condensed model with hardware acceleration by the graphics processing unit (GPU) is proposed. Two methods are developed in order to map the data onto the GPU in accordance with the application data structure. The performance of the primary calculation task in the solver is enhanced. Furthermore, an improved scheme is presented to conduct the newly applied forces induced by dragging or poking operations in the non-operational region.
In the thesis, new approaches to establish a physically based model for soft tissue deformation and cutting in virtual-reality-based simulators are proposed. A deformable model, called the hybrid condensed finite element model, based on the volumetric finite element method is presented. By this method, three-dimensional organs can be represented as tetrahedral meshes, divided into two regions: the operational region and the non-operational one. Different methods treat the regions with different properties in order to balance the computational time and the level of the simulation realism. The condensation technique is applied to only involve the calculation of the surface nodes in the non-operational region while the fully calculation of the volumetric deformation is processed in the operational part. This model guarantees the smooth simulation of cutting operation with the exact cutting path when users manipulate a virtual scalpel. Moreover, we discuss the relevant aspects on what affect the efficiency of implementing the finite element method, as well as the issues considered for choosing the effective solving method to our problem. Three numerical methods have been examined in our model.
Surgical simulator, which benefits from virtual reality techniques, presents a realistic and feasible approach to train inexperienced surgeons within a safe environment. It plays more and more important role in medical field and also changes the world of surgical training. Especially, the minimally invasive microsurgery, which offers patients various attractive advantages over the traditional surgery, has been widely used in otolaryngology, gastroenterology, gynecology and neurology in the last two decades.
Through the combination of these approaches, a physically based model which allows users to freely perform the soft tissue cutting and detecting, such as poking or dragging operations, with soft tissue deformation is achieved in real-time.
Wu Wen.
"August 2006."
Adviser: Pheng Ann Heng.
Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1745.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2006.
Includes bibliographical references (p. 112-127).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in English and Chinese.
School code: 1307.

Implicit models inherently support automatic blending and trivial collision detection which makes them an effective tool for designing complex organic shapes with many applications in various areas of research including surgical simulation systems. However, slow rendering speeds can adversely affect the performance of simulation and modelling systems. In addition, when the models are incorporated in a surgical simulation system, interactive and smooth cutting becomes a required feature for many procedures. In this research, we propose a comprehensive framework for high-performance rendering and physically-based animation of tissues modelled using implicit surfaces. Our goal is to address performance and scalability issues that arise in rendering complex implicit models as well as in dynamic interactions between surgical tool and models. Complex models can be created with implicit primitives, blending operators, affine transformations, deformations and constructive solid geometry in a design environment that organizes all these in a scene graph data structure called the BlobTree. We show that the BlobTree modelling approach provides a very compact data structure which supports the requirements above, as well as incremental changes and trivial collision detection. A GPU-assisted surface extraction algorithm is proposed to support interactive modelling of complex BlobTree models. Using a finite element approach we discretize those models for accurate physically-based animation. Our system provides an interactive cutting ability using smooth intersection surfaces. We show an application of our system in a human skull craniotomy simulation.
Graduate
0984
pourya.shirazian@gmail.com

Choi Kup Sze.
"June 2004."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references (p. 122-127).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.

碩士
中原大學
資訊工程研究所
98
Illustration for medical visualization can achieve the hand-drawn effects or enhance some geometric features such as muscle texture. Illustrative visualization as text illustration provides realistic or enhanced 3D images to achieve better teaching effects than medical volume visualization for residents or students with less clinic experiences. Our methods provide illustration method for the musculoskeletal surgery. Because the relations between operated and neighboring structures, and dissected muscles and skins can be demonstrated, the simulations can be an effective tool for teaching residents and students and rehearsing surgery for surgeons.

碩士
國立成功大學
工業設計學系碩博士班
91
This surgical simulation system of laparoscope is a high - efficiency, low-cost, and more realistic system that were designed by Virtual-Reality. Laparoscopic technology has promoted the surgical field into a new era, by which the operator manipulates extra corporeal instruments via small wound to achieve motion for excision, remedy, suturing and removal. However, the poor coordination between instruments and 2-Dimensional images requires special training system to overcome the steep learning curve. There are many drawbacks for the training system such as pelvic trainer, animal laboratory or classical 3-D virtual reality trainer, etc. The t trainer at present is not only unreal, but also poor training efficiency; the animal laboratory is expensive and has an inherited problem on animal life wasting; the 3-D simulator is more expensive and difficult to develop. Therefore, the objective of this research is to develop a heuristic Laparoscopic Surgical Training System (LSTS) using Virtual Reality and Image Reconstruction Technologies. The advantages of the system are the instructors can easily design the training courses using user-friendly interfaces, and the trainees’ laparoscopic surgical skill can be greatly improved by this low cost and higher realistic training system. The first and the most distinct feature of the design is to simulate abdominal cavity using real 2D images captured from laparoscope instead of building the physical 3D models of organs using high performance computer graphics system. Live Laparoscopic surgical processes are recorded into Digital Video Discs (DVD) to simulate the virtual environment of an abdominal cavity. The paths of surgical tools are recorded using image analysis technology, which are used to evaluate the trainees’ surgical skill during the training courses. Since it is not necessary to build the expensive and non-realistic physical models of organs by complex theorems and time consuming calculations, the system is easily implemented using regular computer. The second feature of the design is that the input hardware of the system was made by the mechanism of joystick and mouse, which lower down the cost of the input system. Joystick and mouse are used to develop the 3D position tracking system to detect the hand motions of instructors and trainees. The 3-D robot arm systems assembled by expensive servomotors and AD/DA cards were not needed in this system anymore. An important innovative design is that two markers film recording together with the image analysis technology to get the paths of surgical tools. It is not necessary to use the expensive optic or magnetic 3-D locators. This will make the laparoscopic surgical training system affordable by medical centers so that new surgeons can be trained continuously and economically. It is important to note that the same ideas and the design logic might be extended to other surgical training systems, either open or endoscopic scenario, to improve new surgeons’ surgical skills in cost-effective ways.

碩士
國立中央大學
資訊工程研究所
85
We have proposed a surgical simulation system; the research topics in the the sisare parts of the system. There are three topics in this thesis: (i) geometr icalmodeling, (ii) cutting operations, and (iii) model reconstruction. At firs t, wepropose a method to construct a geometric model with triangulated irregul arsurface from many slices of color medical images. We sample points from colo rimages and make them a polygon to form the contour of an organ, and link each vertex in a polygon with points on another polygon in the adjacent image tocon struct a complete organ model. Secondly, we build a VR environment and put akn ife and into this environment and operate this knife to cut the model.Moreover , we discuss how to cut a model into two pieces according the knifelocation an d orientation and how to lacerate a breach in the surface of a organ.After cut ting operations, we need to reconstruct a triangles meshes to representthe cut surfaces. We propose an approach to find a jut from a non-convex polygonno ma tter what the contour of the polygon be lined in order or not. Thisprocedure w ill be executed iteratively until all triangles be found that thispolygon can be cut into many triangles in parts.

碩士
國立成功大學
工業與資訊管理學系
104
Duration of surgeries and occurrence of emergency are important random factors in surgical scheduling problem. These factors cannot be known as deterministic values, so the surgical scheduling problem cannot be solved by mathematical programming methods. In our research, we use sample average approximation (SAA) algorithm and rapid screening (RS) to cope with these stochastic factors. In this way, surgical scheduling problem can be solved while its randomness is taken into account. Moreover, we solve surgical scheduling problem via several heuristic methods as well, and compare the results with the ones via SAA and RS.

碩士
中原大學
資訊工程研究所
83
In this thesis, we have developed a 3D image based maxillofacial system that can provide the following function: automatically generating 3D landmarks, measuring based on the landmarks, suggesting possible model and design operations and providing 3D sophisticated surgical simulation environment. We determine the landmarks based on the definitions of 2D cephalometry. However, we correct the definitions to fit the 3D volume data. Then, we measure the 3D deviation of landmarks to compute the maxillary and mandibular deformities. Then, we provide the treatment suggestion for correcting the deformities. Precise diagnosis and treatment planning can be expected by the 3D visible assistance. Our simulation routines allow the clinician to section the anatomical structure from various directions and move the sectioned structure to any place. We compute the new position of soft tissue simultaneously with the reposition of the hard tissue. Because of 3D simulation, the clinician can predicate the result of surgery by computer without manually performing paper surgery and model surgery.

Thesis (M.S.)--State University of New York at Buffalo, 2008.
Title from PDF title page (viewed on Aug. 26, 2008) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Thenkurussi, Kesavadas. Includes bibliographical references.

博士
國立中正大學
機械工程學系暨研究所
102
Dental implant restoration procedure has substantially increased in recent years. There has been continuous and increasing demand for CAD/CAM-based surgical template used to facilitate proper implant placement. Thus, an effective and correct training is becoming more and more important. The aim of this study is to develop a surgical template-based training system via augmented reality (AR) for operator to virtually observe and sense as well as practice the guided implant surgery procedures. Firstly, the 3D virtual volumetric data based on the volume rendering will be generated from 2D medical images. The automatic transfer function will be used to capture bone, teeth, and soft tissue parts. The digital nerve canal, sinus and the customized surgical template models will be built from medical images. Then, AR is utilized to superimpose the 3D virtual models onto the existing scene during the training. The operator could see the planned implants and adjacent anatomical structures of the virtual 3D jawbone on the screen of laptop or head-mounted display (HMD). A haptic device will also be used to provide the force feedback in the drilling and screwing operations in order for the operator to sense the different force feedback during operation. A haptic guiding force will be used to simulate the constrained effect when using the surgical template. Then, an AR-based surgical template is mounted on a cast made according to the clinical patient and fixed it within the dummy head. The operator uses a handpiece and a hand held sleeve insert to practice the dental implant surgery in this dummy head. In addition, we evaluate the accuracy of the virtually planned versus the actual prepared implant site created in vitro by the proposed system. The proposed system is highly applicable to virtual dental training and practices, and for the operator to keep practicing and previewing the location of the implant during operation. The dental implant can be placed in the predetermined location in the patient’s jawbone precisely. The user has the virtual but real perception in vision and touch. Moreover, deviation of implant placement from planned position was significantly reduced by integrating surgical template and augmented reality technology according to the evaluation. Therefore, the proposed system can help users obtain more “like real” practice opportunities and experiences before real operation. Finally, the proposed system can significantly reduce the risk of injury to patients and avoid unnecessary complications during dental implant surgical procedures.

博士
中原大學
電子工程研究所
90
In this thesis, we reveal the importance of surgical simulation, survey the related simulation techniques and realize that volume model is more accurate than others as it can resolve the inner information of anatomic structure. Then, we survey varied volume models with extended data structures and methodologies for manipulating solids, surfaces and find out the insufficiencies of them. We propose a new volume data structure and algorithms for surface representation in a volume, also promote the algorithms that can efficiently manipulate volumetric solids. With these algorithms and data structure, we develop some simulation functions to manipulate volumetric solids and especially simulate musculoskeletal surgery, including collision detection and Boolean operations between solids, tear an anatomic structure (a solid), recognize, reposition the structure and fuse two separate structure, etc. This study testifies the functions with several surgical examples. First, a corrective osteotomy for correcting a maxilla extrusion is demonstrated. This example shows a complex musculoskeletal surgery with complicated topologic and geometric changes can be well simulated by our functions. In the second example, the functions combine with an algorithm of evaluating and analyzing 3D geometric constraints for determining commercial knee prosthesis. The evaluation and analysis results are used as parameters for simulating the knee arthroplasty. In the last example, functions combining HIVD (Herniated Inter-Vertebral Disc) detection method is demonstrated. This method accommodates the radial B-spline to approximate the spline curve composed by disc boundary on slice. We calculate the center of inter-vertebral disc, determine the concave and convex features on the disc based on the change rate of radii and determine the HIVD degree based on the feature characteristics. This method provides effective information for the followed-up HIVD surgical simulation. The first experimental result shows that proposed data structure, algorithms and simulation functions completely fulfill the requirements of simulating the musculoskeletal surgery. The second and last experimental results show the simulation method based on volumetric manipulation can be extended to a diagnosis, verification and treatment tool by combining the related algorithms.

碩士
國立成功大學
資訊及電子工程研究所
83
In this thesis, an integrated system dealing with a serial CT images of human coxal bone has been developed. Some techniques in 3D image processing and computer graphics associated with adequate anatomical knowledge have been adopted. The system is easy to use and convenient in providing medical knowledge; it has been implemented with various functions including 3D re- construction, 3D image segmentation, visualization, some sur- gical simulation, 3D localization and quantization. For 3D image segmentation, we proposed to use "Adjustable 3D deformable model" that is an improved version of "3D deformable model" previously developed in our laboratory. The new method makes the separation between femoral head and coxal bone more general and accurate. Therefore, it can be applied to various cases with different anatomical characteristics. In addition, we also provide a new algorithm named "Model-based 3D region growing" for 3D segmentation. The method makes the image segmentation more realistic and more efficient than other methods do. As to surgical simulation, a good cutting algorithm based on SB(Semi-Boundary) surface data structure has been designed. Many osteotomies can be accurately simulated in an acceptable computation time. In our experiments, two operations are simulated: one is the way of line cutting, and the other is the movement of cutting region. These processes are applied to the coxal bone to simulate the Chiari pelvic osteotomy, which is an osteotomy often used by orthopedic surgeon.

近年来，血管类疾病已经成为人类健康的第一杀手。每年有成百上千万人死于血管疾病。血管介入术是一种非常有前景的血管类疾病的治疗手段。血管介入术是一种微创手术，它已经被广泛的用于治疗中风，血管狭窄，血管瘤等疾病。相对于传统的开放式手术，它具有风险低，恢复快，住院时间短等优点。该疗法通常在透视影像的引导下由导管和导线在血管内协同完成手术过程。因为介入术的复杂性和特殊性，作为介入手术医生的必要技能，掌握手术中手眼协同，各种手术器具的使用和复杂细致的手术流程无疑是一个巨大的挑战。因此，迫切地需要一种高效、安全的训练系统。相对于传统的训练方法，基于虚拟现实技术的训练系统是一种非常好的训练手段。
为了建立一套高仿真的介入手术训练模拟器，首先，我们要为病人的血管网重建三维模型。我们提出了一种自动的提取中心线的方法，用来从分割好的CTA/MRA体数据中获取病人血管网的中心线。基于改进的平行传递算法，沿着这些中心线，生成了一系列连续的标架。根据这些标架，我们构造了血管的横截面，并在此基础上生成了光滑连续的三维血管模型。
其次，作为血管介入术中最基础和最重要的手术器械，我们为导管和导线建立了物理模型。我们提出了一种基于最小势能原理的可变形的模型用于模拟导管和导线对于受力的反应。我们还提出了一个快速并且稳定的多网格算法来保证模拟的真实性和严格的实时交互要求。另外，我们做了几组实验。通过这些实验，验证了多网格算法在稳定性、实时性、模拟的真实性等方面满足了我们对于训练用模拟系统的要求。
再次，为了模拟血管栓塞术的手术过程，我们提出了一种模拟线圈填充血管瘤的过程的新方法。通过加总线圈弯曲变形的弹性势能、血管瘤变形的弹性势能以及外力做的功，我们建立了在血管栓塞术的环境下的总势能模型。为了求解这个模型，我们提出了一个基于有限元方法的求解器。从而模拟了线圈在介入医生的操作下慢慢的进入血管瘤，并缠绕起来的过程。
另外，我们提出了一个分层圆柱网格模型（LCGM）用于模拟在血管网中血流的运动。这一模型在几何上和拓扑结构上都非常适合我们的应用。我们将血液在血管中的流动近似为一维的层流，并用一组线性等式描述了血管网中流速与血压的关系。通过求解这一线性系统，得到了在分层圆柱网格模型下血流的速度场。依据这个血流的速度场，我们采用平流-扩散模型来模拟造影剂在血管中的传播的过程。
Vascular diseases have been becoming the number one cause of death worldwide in recent years. Millions of people were killed by vascular diseases each year. An increasingly promising therapy for treating vascular diseases is Vascular Interventional Radiology (VIR). VIR is a minimally invasive surgery (MIS) procedure, which has been widely used to cure stroke, angiostenosis, aneurysm and etc. A low risk, an accelerated recovery and a shorter stay in hospital are important advantages over the traditional vascular surgery. This therapy is performed by a guidewire-catheter combination inside the blood vessels under the guidance of the fluoroscopic imaging. Because of the complexity and particularity of these procedures, it is a great challenge to master hand-eye coordination, instrument manipulation and procedure protocols for each radiologist mandatory. An efficient and safe training system is needed urgently. In contrast to these traditional training methods, virtual reality (VR) based simulation systems is a pretty good surrogate.
In order to build a high fidelity interventional simulator for physician training, firstly, we reconstructed the three dimensional (3D) model for the vascular network of the patients. An method of automatic skeleton extraction was proposed to acquire the centerline of the vascular network from the segmented volume data from CTA/MRA. A series of continuing frames were generated along with the centerline based on improved parallel transporting method. According to these frames we built the crossections of the vessels and further the 3D vascular model with the smooth meshes.
Secondly, as the most basic and important instruments in the VIR procedure, the catheter and guidewire were modeled and simulated physically. We developed a deformable model to simulate complicated behaviors of guidewires and catheters based on the principle of minimum total potential energy. A fast and stable multigrid solver was proposed to ensure both realistic simulation and real time interaction. A series of experiments were conducted to evaluate our multigrid solver in terms of stability, time performance, the capability of simulating catheter behaviors and the realism of catheter deformation.
Thirdly, to simulate the procedure of embolization, we proposed a novel method to simulate the motion of coil and their interactions with the aneurysm. We formulated the total potential energy in the embolization circumstance by summing up the elastic energy deriving from the bending of coils, the potential energy due to the deformation of the aneurysm and the work by the external forces. A novel FEM-based approach was proposed to simulate the deformation of coils. And the motion of coils and their responses to every input from the interventional radiologist can be calculated globally.
Fourthly, we proposed our Layered Cylindrical Gird Model (LCGM) for simulating blood flow in vascular network, which is pretty suitable for sampling the vascular network geometrically and topologically. The blood flow in vessels was regarded as 1D laminar flow and formulated into a set of linear equations based on the Poiseuille law to describe the relationship between the speed of flow and the pressure. Solving those equations, we got the velocity fields in the blood flow. In terms of the velocity fields, an advection-diffusion model was adopted to simulate the propagation of contrast agent with the blood flow.
Finally, all above techniques and procedures were implemented and integrated into a simulation system for training the medical students to acquire the endovascular skill, and an empirical study was also designed based on a typical selective catheteriza- tion procedure to assess the feasibility and effectiveness of the proposed system.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
最后，我们将所有以上提到的技术和方法集成到模拟系统中用于训练医学院的学生，并使他们获得血管介入术的技能。并且，我们基于一个典型的导管插入术过程，使用经验分析的方法对模拟系统的可用性和效率进行了评估。
Li, Shun.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2012.
Includes bibliographical references (leaves 105-116).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in also Chinese.
Abstract --- p.i
Acknowledgement --- p.vi
Chapter 1 --- Introduction --- p.1
Chapter 2 --- Vascular Modeling --- p.14
Chapter 2.1 --- Introduction and Related Work --- p.14
Chapter 2.2 --- Vascular Skeleton Graph Construction --- p.15
Chapter 2.2.1 --- Chamfer distance transform and Dijkstra's shortest-path algorithm --- p.17
Chapter 2.2.2 --- End vertices retrieval --- p.19
Chapter 2.2.3 --- The algorithm of vascular skeleton extraction --- p.21
Chapter 2.3 --- Vascular Modeling --- p.21
Chapter 2.3.1 --- Tubular Model --- p.21
Chapter 2.3.2 --- Bifurcation Model --- p.23
Chapter 3 --- Catheter Simulation --- p.28
Chapter 3.1 --- Introduction and Related Works --- p.28
Chapter 3.2 --- Catheter Simulation --- p.31
Chapter 3.2.1 --- Kirchhoff Theory of Elastic Rod --- p.32
Chapter 3.2.2 --- Problem Formulation --- p.34
Chapter 3.2.3 --- The Multigrid Iterative Solver --- p.38
Chapter 3.3 --- Collision detection --- p.45
Chapter 3.4 --- Validation of the Catheter Simulation Method --- p.47
Chapter 3.4.1 --- Stability --- p.49
Chapter 3.4.2 --- Time Performance --- p.50
Chapter 3.4.3 --- Preservation of Curved Tip --- p.51
Chapter 3.4.4 --- The realism of catheter deformation --- p.53
Chapter 4 --- Coil Embolization Simulation --- p.59
Chapter 4.1 --- Introduction and Related Work --- p.59
Chapter 4.2 --- Methodology --- p.61
Chapter 4.2.1 --- Total potential energy of a coil --- p.61
Chapter 4.2.2 --- The FEM-based numeric solver for interactive coil simulation --- p.61
Chapter 5 --- Angiography Simulation --- p.70
Chapter 5.1 --- Introduction and related works --- p.70
Chapter 5.2 --- The Equations of Fluid --- p.72
Chapter 5.3 --- Layered Cylindrical Gird Model --- p.73
Chapter 5.4 --- Numerical Method --- p.76
Chapter 5.4.1 --- Evaluation of the velocity field of blood flow --- p.76
Chapter 5.4.2 --- Evaluation of the density field --- p.78
Chapter 5.5 --- Results --- p.81
Chapter 6 --- System Implementation and Evaluation --- p.84
Chapter 6.1 --- Introduction and Related Work --- p.84
Chapter 6.2 --- System Construction --- p.85
Chapter 6.3 --- Empirical Study of the Training System --- p.89
Chapter 7 --- Conclusion and Discussion --- p.98
Chapter 7.1 --- Geometric Modeling of Vasculature --- p.99
Chapter 7.2 --- Catheterization Simulation --- p.99
Chapter 7.3 --- Embolization Simulation --- p.100
Chapter 7.4 --- Angiography Simulation --- p.101
Chapter 7.5 --- System and Evaluation --- p.102
Publication List --- p.103
Bibliography --- p.105