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1.
J Biomed Inform ; 100: 103319, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31655272

RESUMO

To provide natural simulated objects and intuitive user interaction in medical education and training, we propose a naked eye 3D display and interaction system. The current 3D rendering algorithms for naked eye 3D displays are not suitable for medical use, due to the requirements of displaying and interacting with high quality medical images and simulating soft tissues. Because the traditional 3D rendering procedure and vertex indexing in collision detection require substantial computing power when using a naked eye 3D display, the current method cannot achieve fluent displays and interactions. Thus, we develop a novel octree-based 3D rendering and interaction algorithm for high quality medical models to improve the rendering rate and obtain smooth human machine interactions when using the naked eye 3D display device. We also valuate the soft-body phantom simulation of the naked eye 3D display device by combining the traditional 3D rendering algorithm with the elastic 3D simulation to simulate deformable tissues. We integrate an incremental interaction method and a Kalman filter-based hand tracking method to achieve a larger user interaction range and robust hand tracking. We used the proposed system to perform human-computer interactions with rigid phantoms and soft-body phantoms. The experimental results showed that the proposed rendering algorithm for rigid phantoms could achieve higher rendering performance (50 FPS) than the traditional rendering algorithm (9.8 FPS). The user experiments showed that the 3D simulation system equipped with the enhanced rendering algorithm could achieve fluent interactions when using the naked eye 3D display, thus promoting education experiences and reducing task completion times.

2.
IEEE Trans Vis Comput Graph ; 25(3): 1603-1614, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29994155

RESUMO

We propose a unified mathematical model for multilayer-multiframe compressive light field displays that supports both attenuation-based and polarization-based architectures. We show that the light field decomposition of such a display can be cast as a bound constrained nonlinear matrix optimization problem. Efficient light field decomposition algorithms are developed using the limited-memory BFGS (L-BFGS) method for automultiscopic displays with high resolution and high image fidelity. In addition, this framework is the first to support multilayer polarization-based compressive light field displays with time multiplexing. This new architecture significantly reduces artifacts compared with attenuation-based multilayer-multiframe displays; thus, it can allow the requirements regarding the number of layers or the refresh rate to be relaxed. We verify the proposed methods by constructing two 3-layer prototypes using high-speed LCDs, one based on the attenuation architecture and one based on the polarization architecture. Moreover, an efficient CUDA-based program is implemented. Our displays can produce images with higher spatial resolution with thinner form factors compared with traditional automultiscopic displays in both simulations and experiments.

3.
Adv Exp Med Biol ; 1093: 193-205, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30306483

RESUMO

Augmented reality (AR) techniques play an important role in the field of minimally invasive surgery for orthopedics. AR can improve the hand-eye coordination by providing surgeons with the merged surgical scene, which enables surgeons to perform surgical operations more easily. To display the navigation information in the AR scene, medical image processing and three-dimensional (3D) visualization of the important anatomical structures are required. As a promising 3D display technique, integral videography (IV) can produce an autostereoscopic image with full parallax and continuous viewing points. Moreover, IV-based 3D AR navigation technique is proposed to present intuitive scene and has been applied in orthopedics, including oral surgery and spine surgery. The accurate patient-image registration, as well as the real-time target tracking for surgical tools and the patient, can be achieved. This paper overviews IV-based AR navigation and the applications in orthopedics, discusses the infrastructure required for successful implementation of IV-based approaches, and outlines the challenges that must be overcome for IV-based AR navigation to advance further development.


Assuntos
Imagem Tridimensional , Procedimentos Cirúrgicos Bucais , Ortopedia , Cirurgia Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador , Interface Usuário-Computador
4.
Sci Rep ; 8(1): 15863, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367129

RESUMO

Three-dimensional (3-D) autostereoscopic display with dedicated multiple spatial information under corresponding illumination is critical, especially for anti-counterfeiting, entertainment, etc. In this paper, we propose a 3-D spatial floating display using multi-wavelength integral photography (IP). Using dedicated inkjet printer and refraction-based IP algorithm, a complex two-dimensional (2-D) elemental image array (EIA) can be printed for both fluorescent and normal 3-D autostereoscopic display. With a micro-convex lens array (MLA) and a medium attached on the EIA, normal 3-D images are reconstructed under visible light, while fluorescent 3-D images can be reconstructed under ultraviolet (UV) light. Moreover, to provide comfortable 3-D images with multiple information in space, a feasible 3-D spatial floating display system is also proposed considering the spatial position of the observer with less UV radiation. The proposed method takes the wavelength of 3-D display into consideration to provide spatial multi-information, and can be applied for media, entertainment, etc. Experimental results verified the availability of the proposed method.

5.
IEEE Trans Biomed Eng ; 65(2): 378-389, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29346106

RESUMO

We develop a spatial position measurement system using three-dimensional (3-D) image marker-based tracking tools targeted at surgical navigation in minimally invasive surgery. We generate 3-D image markers with spatial information encoded to 2-D images, design tracking tools with the 3-D image markers, and analyze the tracking tools' theoretical spatial errors, which are primarily limited by the spatial distribution of reconstructed fiducial 3-D markers. A pattern analysis-based positional measurement algorithm is developed to calculate the tool's spatial information using its spatial configuration. Evaluation experiments were conducted to demonstrate the accuracy and effectiveness of the proposed system. Furthermore, surgical navigation feasibility studies were performed. With a patient-image registration algorithm, a navigation interface that shows preoperative medical data and intraoperative information about the tool can intuitively and accurately assist surgeons. The results demonstrate that the proposed tracking tools, which have compact volume and spatial positional information, are of potential use in minimally invasive surgery in a limited space.


Assuntos
Imagem Tridimensional/métodos , Cirurgia Assistida por Computador/métodos , Algoritmos , Marcadores Fiduciais , Mãos/diagnóstico por imagem , Mãos/cirurgia , Humanos , Imagens de Fantasmas , Crânio/diagnóstico por imagem , Crânio/cirurgia
6.
IEEE Trans Vis Comput Graph ; 24(9): 2600-2609, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-28961116

RESUMO

We propose a computer generated integral photography (CGIP) method that employs a lens based rendering (LBR) algorithm for super-multiview displays to achieve higher frame rates and better image quality without pixel resampling or view interpolation. The algorithm can utilize both fixed and programmable graphics pipelines to accelerate CGIP rendering and inter-perspective antialiasing. Two hardware prototypes were fabricated with two high-resolution liquid crystal displays and micro-lens arrays (MLA). Qualitative and quantitative experiments were performed to evaluate the feasibility of the proposed algorithm. To the best of our knowledge, the proposed LBR method outperforms state-of-the-art CGIP algorithms relative to rendering speed and image quality with our super-multiview hardware configurations. A demonstration experiment was also conducted to reveal the interactivity of a super-multiview display utilizing the proposed algorithm.

7.
J Opt Soc Am A Opt Image Sci Vis ; 34(5): 804-812, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28463324

RESUMO

Quality of three-dimensional (3D) autostereoscopic displays is mainly influenced by the mismatch between the optical apparatus setups and image generation algorithms. In this paper, we take the optical apparatus setups into consideration and present an accurate 3D autostereoscopic display method using optimized parameters through quantitative calibration. Rotational and translational alignments are operated quantitatively to rectify the optical apparatus. In addition, the main parameters in a 3D display are evaluated for accurate 3D image rendering. Using the proposed method, the 3D autostereoscopic display can be calibrated quantitatively and provide 3D images with accurate spatial information. Experiments verified the availability and feasibility of the proposed method.

8.
J Biomed Inform ; 71: 154-164, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28533140

RESUMO

Three-dimensional (3D) visualization of preoperative and intraoperative medical information becomes more and more important in minimally invasive surgery. We develop a 3D interactive surgical visualization system using mobile spatial information acquisition and autostereoscopic display for surgeons to observe surgical target intuitively. The spatial information of regions of interest (ROIs) is captured by the mobile device and transferred to a server for further image processing. Triangular patches of intraoperative data with texture are calculated with a dimension-reduced triangulation algorithm and a projection-weighted mapping algorithm. A point cloud selection-based warm-start iterative closest point (ICP) algorithm is also developed for fusion of the reconstructed 3D intraoperative image and the preoperative image. The fusion images are rendered for 3D autostereoscopic display using integral videography (IV) technology. Moreover, 3D visualization of medical image corresponding to observer's viewing direction is updated automatically using mutual information registration method. Experimental results show that the spatial position error between the IV-based 3D autostereoscopic fusion image and the actual object was 0.38±0.92mm (n=5). The system can be utilized in telemedicine, operating education, surgical planning, navigation, etc. to acquire spatial information conveniently and display surgical information intuitively.


Assuntos
Processamento de Imagem Assistida por Computador , Imagem Tridimensional , Procedimentos Cirúrgicos Operatórios , Telemedicina , Algoritmos , Humanos
9.
Conf Proc IEEE Eng Med Biol Soc ; 2015: 4226-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26737227

RESUMO

Autostereoscopic has long been proposed to fulfill medical display in image-guided surgery and clinical education to provide more intuitive position information of clinical interest zone thus improving surgery safety and accuracy. As one category of flexible autostereoscopic 3D display, computer generated integral photography (CGIP) has been studied in medical application by many researches for its convenience and cost-efficiency. However, IP still suffers from inaccurate light field reconstruction, which limits its practicality in surgery. In this paper, we propose and apply a flexible fish-eye model based micro lens array (MLA) distortion calibration method and pre-distorted retracing rendering algorithm to render elemental image array (EIA) of CGIP. Furthermore, we also evaluate light field of the proposed algorithm in depth cue, and signal noise ratio of IP images by phantom experiment.


Assuntos
Imagem Tridimensional/métodos , Fotografação/métodos , Crânio/patologia , Cirurgia Assistida por Computador/métodos , Algoritmos , Calibragem , Diagnóstico por Imagem/métodos , Desenho de Equipamento , Humanos , Lentes , Modelos Estatísticos , Imagens de Fantasmas , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído
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