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3D surface imaging

James L Robar, Kathryn Moran, James Allan, James Clancey, Tami Joseph, Krista Chytyk-Praznik, R Lee MacDonald, John Lincoln, Parisa Sadeghi, Robert Rutledge
PURPOSE: This patient study evaluated the use of 3-dimensional (3D) printed bolus for chest wall radiation therapy compared with standard sheet bolus with regard to accuracy of fit, surface dose measured in vivo, and efficiency of patient setup. By alternating bolus type over the course of therapy, each patient served as her own control. METHODS AND MATERIALS: For 16 patients undergoing chest wall radiation therapy, a custom 5.0 mm thick bolus was designed based on the treatment planning computed tomography scan and 3D printed using polylactic acid...
December 24, 2017: Practical Radiation Oncology
Emile S Farag, Pim van Ooij, R Nils Planken, Kayleigh C P Dukker, Frederiek de Heer, Berto J Bouma, Danielle Robbers-Visser, Maarten Groenink, Aart J Nederveen, Bas A J M de Mol, Jolanda Kluin, S Matthijs Boekholdt
BACKGROUND: Use of 4-dimensional flow magnetic resonance imaging (4D-flow MRI) derived wall shear stress (WSS) heat maps enables identification of regions in the ascending aorta with increased WSS. These regions are subject to dysregulation of the extracellular matrix and elastic fiber degeneration, which is associated with aortic dilatation and dissection. PURPOSE: To evaluate the effect of the presence of aortic valve stenosis and the aortic diameter on the peak WSS and surface area of increased WSS in the ascending aorta...
February 16, 2018: Journal of Magnetic Resonance Imaging: JMRI
Xiao-Wen Cao, Qi-Dai Chen, Lei Zhang, Zhen-Nan Tian, Qian-Kun Li, Lei Wang, Saulius Juodkazis, Hong-Bo Sun
This work developed a method of femtosecond laser (fs-laser) parallel processing assisted by wet etching to fabricate 3D micro-optical components. A 2D fs-laser spot array with designed spatial distribution was generated by a spatial light modulator. A single-pulse exposure of the entire array was used for parallel processing. By subsequent wet etching, a close-packed hexagonal arrangement, 3D concave microlens array on a curved surface with a radius of approximately 120 μm was fabricated, each unit lens of which has designable spatial distribution...
February 15, 2018: Optics Letters
Christopher Gloschat, Kedar Aras, Shubham Gupta, N Rokhaya Faye, Hanyu Zhang, Roman A Syunyaev, Roman A Pryamonosov, Jack Rogers, Matthew W Kay, Igor R Efimov
Fluorescence optical imaging techniques have revolutionized the field of cardiac electrophysiology and advanced our understanding of complex electrical activities such as arrhythmias. However, traditional monocular optical mapping systems, despite having high spatial resolution, are restricted to a two-dimensional (2D) field of view. Consequently, tracking complex three-dimensional (3D) electrical waves such as during ventricular fibrillation is challenging as the waves rapidly move in and out of the field of view...
February 13, 2018: Scientific Reports
Thomas Yi, Vignesh Ramchandran, Jeffrey H Siewerdsen, Ali Uneri
A method for x-ray image-guided robotic instrument positioning is reported and evaluated in preclinical studies of spinal pedicle screw placement with the aim of improving delivery of transpedicle K-wires and screws. The known-component (KC) registration algorithm was used to register the three-dimensional patient CT and drill guide surface model to intraoperative two-dimensional radiographs. Resulting transformations, combined with offline hand-eye calibration, drive the robotically held drill guide to target trajectories defined in the preoperative CT...
April 2018: Journal of Medical Imaging
Yumi Takano, Keiko Kunitoki, Yasuko Tatewaki, Tatsushi Mutoh, Tomoko Totsune, Hideo Shimomura, Manabu Nakagawa, Hiroyuki Arai, Yasuyuki Taki
BACKGROUND Semantic dementia (SD) is a type of primary progressive aphasia with prominent language dysfunction, mostly within the spectrum of frontotemporal lobar degeneration (FTLD). Although there is an overlap in clinical manifestations of SD attributable to FTLD and neuropathologically proven Alzheimer disease (AD), clinical diagnostic clues are not readily available. We present a characteristic finding based on a single-photon emission computed tomography (SPECT)-based regional cerebral blood flow study and its statistical imaging analysis for a rare case of SD with AD-like pathology...
February 12, 2018: American Journal of Case Reports
Leila Fathyunes, Jafar Khalil-Allafi
In the present work, we investigated the effect of employing ultrasonic waves during pulse electrochemical deposition on surface topography, chemical composition and biocompatibility of calcium phosphate (Ca-P) coatings. The SEM and 3D AFM images showed that the anodized titanium surface was covered with the uniform and refined size of plate-like Ca-P crystals, when the ultrasonic treatment of the electrolyte with power of 60 W was carried out during deposition. In contrast, for the Ca-P; 0 W coating applied under only the magnetic stirring of the electrolyte, the microstructure was non-uniform and some Ca-P crystals with the larger size were randomly observed in different regions, causing a rougher surface...
April 2018: Ultrasonics Sonochemistry
Beata Śmielak, Leszek Klimek
Background: Determination of the number of abrasive particles embedded in the zirconia surface after variable parameters of treatment. METHODS: One hundred thirty cylindrical disks made from zirconia were divided into 7 groups (n = 10): one control and six test groups treated by air abrasion using Al₂O₃ or SiC with grain sizes: 60, 110, 250 μm with a working pressure of 0.2 or 0.35 MPa. The SEM images were observed in BSE and BSE 3D. The chemical composition was determined by means of X-ray microanalysis with EDS...
February 8, 2018: Materials
Massimo Milani, Adele Sparavigna
Background: Skin is a complete and independent melatoninergic system. At the skin level, melatonin (Mel) acts as a relevant antioxidant and cytoprotective substance. Topical application of Mel is considered meaningful, since it can easily penetrate the stratum corneum. Exogenous Mel can be expected to represent a potent antioxidative defense system against skin aging mechanisms. Day and night creams containing Mel, carried in lipospheres (Melatosphere™), have been developed (Nutriage SPF 30 day cream and Nutriage night cream)...
2018: Clinical, Cosmetic and Investigational Dermatology
Ying Tong, Yong Yin, Jie Lu, Tonghai Liu, Jinhu Chen, Pinjing Cheng, Guanzhong Gong
Purpose: The purpose of this study was to quantify variations in the heart, pericardium, and left ventricular myocardium (LVM) caused by cardiac movement using the breath-hold technique. Patients and methods: In this study, the electrocardiography-gated four-dimensional computed tomography (CT) images of 22 patients were analyzed, which were sorted into 20 phases (0-95%) according to the cardiac cycle. The heart, pericardium, and LVM were contoured on each phase of the CT images...
2018: OncoTargets and Therapy
Igor Peterlík, Hadrien Courtecuisse, Robert Rohling, Purang Abolmaesumi, Christopher Nguan, Stéphane Cotin, Septimiu Salcudean
A fast and accurate fusion of intra-operative images with a pre-operative data is a key component of computer-aided interventions which aim at improving the outcomes of the intervention while reducing the patient's discomfort. In this paper, we focus on the problematic of the intra-operative navigation during abdominal surgery, which requires an accurate registration of tissues undergoing large deformations. Such a scenario occurs in the case of partial hepatectomy: to facilitate the access to the pathology, e...
December 20, 2017: Medical Image Analysis
Borhan Alhosseini Hamedani, Alexa Melvin, Kirubahara Vaheesan, Sameer Gadani, Keith Pereira, Andrew F Hall
PURPOSE: The goal of this work was to develop phantoms for the optimization of pre-operative computed tomography (CT) scans of the prostate artery, which are used for embolization planning. METHODS: Acrylonitrile butadiene styrene (ABS) pellets were doped with barium sulfate and extruded into filaments suitable for 3D printing on a fused deposition modeling (FDM) printer. Cylinder phantoms were created to evaluate radiopacity as a function of doping percentage. Small-diameter tree phantoms were created to assess their composition and dimensional accuracy...
February 7, 2018: Journal of Applied Clinical Medical Physics
Jieyu Cheng, Yimin Chen, Yanyan Yu, Bernard Chiu
Total plaque volume (TPV) measured from 3D carotid ultrasound has been shown to be able to predict cardiovascular events and is sensitive in detecting treatment effects. Manual plaque segmentation was performed in previous studies to quantify TPV, but is tedious, requires long training times and is prone to observer variability. This article introduces the first 3D direct volume-based level-set algorithm to segment plaques from 3D carotid ultrasound images. The plaque surfaces were first initialized based on the lumen and outer wall boundaries generated by a previously described semi-automatic algorithm and then deformed by a direct three-dimensional sparse field level-set algorithm, which enforced the longitudinal continuity of the segmented plaque surfaces...
January 11, 2018: Computers in Biology and Medicine
Jaeyong Song, Junhyung Kim, Heung-Myung Woo, Byungil Yoon, Hyunjung Park, Chanhum Park, Byung-Jae Kang
Our study aimed to investigate the effect of bone morphogenetic protein-2 (BMP-2) bound to silk fibroin and β-tricalcium phosphate (SF/β-TCP) hybrid on the healing of critical-size radial defects in rabbits. A 15-mm critical-size defect was induced at mid-diaphysis in the left radius of 20 New Zealand white rabbits (average age, 3.5 months; weight, 2.5-3.0 kg). The animals were randomized into Group 1 (SF/β-TCP combined with BMP-2), Group 2 (SF/β-TCP alone), and Group 3 (nothing implanted). Radiographs were obtained every 2 weeks and euthanasia was performed after 8 weeks for visual, radiological, micro-computed tomography (micro-CT), and histological studies...
February 6, 2018: Journal of Biomaterials Science. Polymer Edition
Michael R Abel, Linda H Nie
PURPOSE: The purpose of this study is to develop and employ a Monte Carlo (MC) simulation model of associated particle neutron elemental imaging (APNEI) in order to determine the three-dimensional (3D) imaging resolution of such a system by examining relevant physical and technological parameters and to thereby begin to explore the range of clinical applicability of APNEI to fields such as medical diagnostics, intervention, and etiological research. METHODS: The presented APNEI model was defined in MCNP by a Gaussian-distributed and isotropic surface source emitting deuterium + deuterium (DD) neutrons, iron as the target element, nine iron-containing voxels (1 cm3 volume each) arranged in a 3-by-3 array as the interrogated volume of interest, and finally, by high-purity germanium (HPGe) gamma-ray detectors anterior and posterior to the 9-voxel array...
February 6, 2018: Medical Physics
Juhui Ko, Sung-Gyu Park, Sangyeop Lee, Xiaokun Wang, ChaeWon Mun, Sunho Kim, Dong-Ho Kim, Jaebum Choo
We utilized a fast Raman spectral mapping technique for fast detection of bacterial pathogens. Three-dimensional (3D) plasmonic nanopillar arrays were fabricated using the nanolithography-free process consisting of maskless Ar plasma treatment of a polyethylene terephthalate (PET) substrate and subsequent metal deposition. Bacterial pathogens were immobilized on the positively charged poly(L-lysine) (PLL)-coated 3D plasmonic substrate through electrostatic interactions. Then the bacterial surfaces were selectively labeled with antibody-conjugated surface-enhanced Raman scattering (SERS) nanotags, and Raman mapping images were collected and statistically analyzed for quantitative analysis of bacteria...
February 6, 2018: ACS Applied Materials & Interfaces
Yeoan Youn, Yuji Ishitsuka, Chaoyi Jin, Paul R Selvin
Localization-based super-resolution microscopy enables imaging of biological structures with sub-diffraction-limited accuracy, but generally requires extended acquisition time. Consequently, stage drift often limits the spatial precision. Previously, we reported a simple method to correct for this by creating an array of 1 μm3 fiducial markers, every ~8 μm, on the coverslip, using UV-nanoimprint lithography (UV-NIL). While this allowed reliable and accurate 3D drift correction, it suffered high autofluorescence background with shorter wavelength illumination, unstable adsorption to the substrate glass surface, and suboptimal biocompatibility...
January 22, 2018: Optics Express
Zhenqi Niu, Nan Gao, Zonghua Zhang, Feng Gao, Xiangqian Jiang
This paper presents an advanced phase measuring deflectometry (PMD) method based on a novel mathematical model to obtain three dimensional (3D) shape of discontinuous specular object using a bi-telecentric lens. The proposed method uses an LCD screen, a flat beam splitter, a camera with a bi-telecentric lens, and a translating stage. The LCD screen is used to display sinusoidal fringe patterns and can be moved by the stage to two different positions along the normal direction of a reference plane. The camera captures the deformed fringe patterns reflected by the measured specular surface...
January 22, 2018: Optics Express
Jae-Sang Hyun, George T-C Chiu, Song Zhang
This paper presents a method to achieve high-speed and high-accuracy 3D surface measurement using a custom-designed mechanical projector and two high-speed cameras. We developed a computational framework that can achieve absolute shape measurement in sub-pixel accuracy through: 1) capturing precisely phase-shifted fringe patterns by synchronizing the cameras with the projector; 2) generating a rough disparity map between two cameras by employing a standard stereo-vision method using texture images with encoded statistical patterns; and 3) utilizing the wrapped phase as a constraint to refine the disparity map...
January 22, 2018: Optics Express
Shoaib R Soomro, Hakan Urey
We propose an integrated 3D display and imaging system using a head-mounted device and a special dual-purpose passive screen that can simultaneously facilitate 3D display and imaging. The screen is mainly composed of two optical layers, the first layer is a projection surface, which are the finely patterned retro-reflective microspheres that provide high optical gain when illuminated with head-mounted projectors. The second layer is an imaging surface made up of an array of curved mirrors, which form the perspective views of the scene captured by a head-mounted camera...
January 22, 2018: Optics Express
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