3D Image Acquisition with Active Lighting

Accurate Transrectal Ultrasound (TRUS)-guided prostate needle biopsy requires registering preoperative 3D TRUS or MR image, in which tumors and other suspicious areas are visible, to intraoperative 2D TRUS images. Such image registration is time-consuming while its real-time implementation is yet to be developed. To bypass this registration step, robotic needle biopsy systems can be used to place the US probe at the same position relative to the prostate during the 3D and 2D image acquisition to ensure similar prostate deformation. To have such similar deformation, only visual feedback is not sufficient as such feedback can be used to only guarantee that the whole prostate is within the field of view irrespective of the probe's orientation. As such, contact pressure feedback can be utilized to ensure consistent minimum contact between the probe and prostate. A robotic system is proposed where a TRUS probe with pressure sensor array is used. The contact pressure can be measured during imaging and used to provide feedback in conjunction with an optimization algorithm for consistent probe positioning. The robotic system is driven by the feedback to position the probe such that pressure pattern of the sensors during 2D image acquisition is similar to the pressure pattern during 3D image acquisition. The proposed method takes into account the patient's body movement expected during image acquisition. In this study, an in silico phantom is used where the simulated contact pressure distribution required in the optimization algorithm is obtained using a prostate finite element model. Starting from an arbitrary position where the probe contacts the phantom, this position was varied systematically until a position corresponding to maximum pressure pattern similarity between contact pressure patterns corresponding to the 2D and 3D imaging was achieved successfully. Results obtained from the in silico phantom study indicate that the proposed technique is capable of ensuring having only minimal relative prostate deformation between preoperative image acquisition and intraoperative imaging used for guiding needle biopsy, paving the way for faster and more accurate registration.

A compressive Holoscopy for 3D high resolution optical imaging acquisition method is proposed. By using compressive sensing theory in holoscopy, we fully reconstruct the wave field from a single holoscopy with only 10% sampling ratio.

Foreshortening is a recognized problem that is present in angiography and results from views that are not perpendicular to coronary lesions. This limits visual coronary analysis as well as 2D quantitative coronary angiography systems (QCA). The CardiOp-B System is a 3D image acquisition and processing software system designed as an add-on to conventional X-ray angiography system. CardiOp-B's features include real time and off line analysis with comprehensive 3D reconstruction integrating all of the available information of two 2D vessel angiographies into one 3D image. It was the aim of the study to analyze the accuracy of this new 3D QCA system. 3D QCA was performed in 50 patients (age 64 +/- 10.9; 84% male; LV-EF 63 +/- 16%) measuring 61 stents during high-pressure inflation (diameter: 2.25-4 mm; length: 8-32 mm). The obtained values (proximal and distal stent diameter, stent length) were correlated with the predefined size of the stents at the used inflation pressure. The linear correlation for the proximal stent diameter was Stent(prox)= 0.03 + 0.93 x real stent size (r(2) = 0.85). The linear correlation for the distal stent diameter was Stent(distal)= -0.03 + 0.89 x real stent size (r(2) = 0.81). The linear correlation for the stent length was Stent(length)= -0.61 + 1.02 x real stent length (r(2) = 0.98). The CardiOp-B System(R) is a new 3D QCA system with a high linear correlation between the real vessel size and the obtained vessel dimension. It provides real time or off line accurate and comprehensive diagnostic information to the interventional cardiologist without changing the basic coronary angiography procedure.

A novel method for simultaneously acquiring and registering range data of a real object from different viewpoints is presented. Currently, most 3D model reconstruction techniques do not cooperate with the existing range data for shape recovery of future viewpoints. In this work, a stereo vision system is developed for 3D model acquisition. To reduce the computation and increase the accuracy of stereo matching algorithms, the recovered range data from previous viewpoints are registered and then used to provide additional constraints for 3D acquisition of the next viewpoint. Experiments have shown that our approach gives better performance on both execution time and stereo matching results.

Remote display and interaction of 3D reconstruction of medical images has been achieved utilizing VTK (the Visualization Toolkit) and HTML5. Aiming at the problem that the network coordination of the medical 3D reconstruction platforms are generally unsatisfactory, the feasibility of achieving multi-frames-based remote interaction of 3D reconstruction of medical images using Canvas and WebSocket in HTML5 has been discussed and verified by experiments. Furthermore, a method to display 3D images on pure Web client based on B/S (Browser/Server) framework has been put forward. The 3D reconstruction system with the application of this method has been proved to be effective in displaying and interacting on both PC and mobile platform with almost real-time effects. This feasible method has certain practical application in remote medical assistance.

This Targeting to the complexity and large amount of 3D(three-dimensional) reconstruction of complex scene in virtual environment, Firstly, The 3D data acquisition and conversion principle, scene modeling and texture mapping method were described. Secondly, the geometric modeling and image fusion method was presented. Thirdly, the reconstruction mathematical model of image based on entropy variation were introduced, and then data compression algorithm to reduce the number of the entity grid was given. Besides, the intricate and fine animal wood carving model on the roof was an example, which was optimized and reconstructed. At last, a classical Chinese architecture was used as a prototype for the fusion modeling and optimization, and merging with virtual software a 3D reconstruction of classical architecture and the scene Navigation system in virtual environment was developed with VC++.

Digital holography offers a reliable and fast method to image a three-dimensional scene from a single perspective. Recent developments of self-reference single-channel incoherent hologram recorders are reviewed herein.

To compare sonographic visualization of midline cerebral structures obtained by two-dimensional (2D) imaging and three-dimensional (3D) multiplanar and volume contrast imaging in the coronal plane (VCI-C), with transfrontal 3D acquisition. Sixty consecutive healthy fetuses in vertex presentation at a mean gestational age of 24 (range, 20-33) weeks underwent 2D and 3D ultrasound examination. Sagittal cerebral planes were reconstructed using 3D acquisition from axial planes by multiplanar analysis and by VCI-C. The reconstructed midline images of both these techniques were compared with the midline structures visualized directly in the A-plane by transfrontal 3D acquisition using a sweep angle of 30 degrees . Measurement of the corpus callosum and cerebellar vermis and visualization of the fourth ventricle and the main vermian fissures were compared. The sharpness of the images was also assessed qualitatively. Mid-sagittal tomographic ultrasound imaging (TUI) was also performed. 3D planes were compared with 2D transfontanelle median planes obtained by transabdominal or, when required, transvaginal sonography. The midline plane could be obtained in 88% of multiplanar, 82% of VCI-C and 87% of transfrontal analyses. Measurements of the corpus callosum and cerebellar vermis obtained by 3D median planes were highly correlated. The clearest and sharpest definition of midline structures was obtained with transfrontal acquisition. Primary and secondary fissures of the cerebellar vermis could be detected in 13-26% of multiplanar, 18-35% of VCI-C and 52-79% of transfrontal analyses. 2D visualization was superior or equal to the 3D transfrontal approach in all the parameters compared. 3D planes obtained from axial acquisitions are simpler and easier to display than are transfrontal ones. However, artifacts and acoustic shadowing are frequent in 3D axial acquisition and spatial resolution is better in the direct visualization transfrontal technique. If the standard examination includes a view of the fetal facial profile, a quick 3D acquisition through the frontal sutures provides direct visualization for assessment of the midline structures. We believe that this volumetric methodology could represent a step towards incorporating a comprehensive fetal neuroscan into routine targeted organ evaluation.

In this paper, compressive sensing based high-speed time-stretch optical microscopy for two-dimensional (2D) image acquisition is proposed and experimentally demonstrated for the first time. A section of dispersion compensating fiber (DCF) is used to perform wavelength-to-time conversion and then ultrafast spectral shaping of broadband optical pulses can be achieved via high-speed intensity modulation. A 2D spatial disperser comprising a pair of orthogonally oriented dispersers is employed to produce spatially structured illumination for 2D image acquisition and a section of single mode fiber (SMF) is utilized for pulse compression in the optical domain. In our scheme, a 1.2-GHz photodetector and a 50-MHz analog-to-digital converter (ADC) are used to acquire the energy of the compressed pulses. Image reconstructions are demonstrated at a frame rate of 500 kHz and a sixteen-fold image compression is achieved in our proof-of-concept demonstration.

1 - 3D Echocardiographic Image Acquisition, Display, and Analysis

A new gonioreflectometer has been developed at the National Research Council of Canada to measure spectral bidirectional reflectance distribution functions (BRDF). It incorporates a five-axis robot manipulator and allows the spectral sampling of the BRDF of reflective materials for arbitrary angles of irradiation and detection. One application will be the characterization of calibration and test targets used in 3D multispectral image acquisition systems.

Three-dimensional (3D) printing is a rapidly evolving technology with severalpotential applications in the diagnosis and management of cardiac disease. Recently,3D printing (i.e. rapid prototyping) derived from 3D transesophageal echocardiography(TEE) has become possible. Due to the multiple steps involved and the specificequipment required for each step, it might be difficult to start implementingechocardiography-derived 3D printing in a clinical setting. In this review, weprovide an overview of this process, including its logistics and organization oftools and materials, 3D TEE image acquisition strategies, data export, formatconversion, segmentation, and printing. Generation of patient-specific models ofcardiac anatomy from echocardiographic data is a feasible, practical application of3D printing technology.

A 2D-based palmprint authentication system is easily fooled by spoof attacks, such as a fake palmprint. To solve that problem, we present a multifeature palmprint authentication system using both 2D and 3D palmprint features in this chapter. This chapter is organized as follows: Sect. 6.1 briefly introduces the background of 2D- and 3D-based palmprint authentication systems. Section 6.2 presents a multifeature palmprint authentication system and the 2D and 3D palmprint image acquisition device. In Sect. 6.3, 2D and 3D feature extraction algorithms are presented. In Sect. 6.4, we present a 2D features matching algorithm for 2D palmprint verification, and then present a 3D features matching algorithm for 3D palmprint authentication. Some experiments are reported to illustrate the robustness of the presented algorithm in Sect. 6.5. The chapter is concluded in Sect. 6.6.

Fluorescence Anisotropy Imaging in 3D with Single Plane Illumination Microscopy

Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging.