keyword
MENU ▼
Read by QxMD icon Read
search

3D scan

keyword
https://www.readbyqxmd.com/read/27915125/artificial-neural-networks-as-a-powerful-numerical-tool-to-classify-specific-features-of-a-tooth-based-on-3d-scan-data
#1
Stefan Raith, Eric Per Vogel, Naeema Anees, Christine Keul, Jan-Frederik Güth, Daniel Edelhoff, Horst Fischer
Chairside manufacturing based on digital image acquisition is gainingincreasing importance in dentistry. For the standardized application of these methods, it is paramount to have highly automated digital workflows that can process acquired 3D image data of dental surfaces. Artificial Neural Networks (ANNs) arenumerical methods primarily used to mimic the complex networks of neural connections in the natural brain. Our hypothesis is that an ANNcan be developed that is capable of classifying dental cusps with sufficient accuracy...
November 27, 2016: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/27913902/a-new-multiscale-micromechanical-model-of-vertebral-trabecular-bones
#2
Rami Haj-Ali, Eyass Massarwa, Jacob Aboudi, Fabio Galbusera, Uwe Wolfram, Hans-Joachim Wilke
A new three-dimensional (3D) multiscale micromechanical model has been suggested as adept at predicting the overall linear anisotropic mechanical properties of a vertebral trabecular bone (VTB) highly porous microstructure. A nested 3D modeling analysis framework spanning the multiscale nature of the VTB is presented herein. This hierarchical analysis framework employs the following micromechanical methods: the 3D parametric high-fidelity generalized method of cells (HFGMC) as well as the 3D sublaminate model...
December 2, 2016: Biomechanics and Modeling in Mechanobiology
https://www.readbyqxmd.com/read/27913880/forensic-3d-documentation-of-skin-injuries
#3
Chiara Villa
An accurate and precise documentation of injuries is fundamental in a forensic pathological context. Photographs and manual measurements are taken of all injuries during autopsies, but ordinary photography projects a 3D wound on a 2D space. Using technologies such as photogrammetry, it is possible to create 3D detailed, to-scale, true-color documentation of skin injuries from 2D pictures. A comparison between the measurements of 165 lesions taken during autopsies and on photogrammetrically processed pictures was performed...
December 2, 2016: International Journal of Legal Medicine
https://www.readbyqxmd.com/read/27913653/dimensional-evaluation-of-patient-specific-3d-printing-using-calcium-phosphate-cement-for-craniofacial-bone-reconstruction
#4
Liciane Sabadin Bertol, Rodrigo Schabbach, Luís Alberto Loureiro Dos Santos
The 3D printing process is highlighted nowadays as a possibility to generate individual parts with complex geometries. Moreover, the development of 3D printing hardware, software and parameters permits the manufacture of parts that can be not only used as prototypes, but are also made from materials that are suitable for implantation. In this way, this study investigates the process involved in the production of patient-specific craniofacial implants using calcium phosphate cement, and its dimensional accuracy...
December 1, 2016: Journal of Biomaterials Applications
https://www.readbyqxmd.com/read/27910824/accelerated-high-resolution-photoacoustic-tomography-via-compressed-sensing
#5
Simon Arridge, Paul Beard, Marta Betcke, Ben Cox, Nam Huynh, Felix Lucka, Olumide Ogunlade, Edward Zhang
Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several minutes to sequentially map the incident photoacoustic field on the 2D sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant...
December 21, 2016: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/27910717/dose-optimisation-for-assessment-of-periodontal-structures-in-cone-beam-ct-examinations
#6
Ayman Al-Okshi, Chrysoula Theodorakou, Christina Lindh
OBJECTIVE: To investigate the relationship between dose and image quality for a dedicated dental Cone Beam CT (CBCT) scanner using different scanning protocols and to set up an optimal imaging protocol for assessment of periodontal structures. METHODS: Radiation dose and image quality measurements were made using the 3D Accuitomo 170 dental CBCT scanner. The SedentexCT IQ phantom was used to investigate the relationship between contrast-to-noise ratio (CNR) and dose-area product (DAP)...
December 2, 2016: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/27909130/the-use-of-ultra-low-dose-ct-scans-for-the-evaluation-of-limb-fractures-is-the-reduced-effective-dose-using-ct-in-orthopaedic-injury-reduction-protocol-effective
#7
S R Konda, A M Goch, P Leucht, A Christiano, S Gyftopoulos, G Yoeli, K A Egol
AIMS: To evaluate whether an ultra-low-dose CT protocol can diagnose selected limb fractures as well as conventional CT (C-CT). PATIENTS AND METHODS: We prospectively studied 40 consecutive patients with a limb fracture in whom a CT scan was indicated. These were scanned using an ultra-low-dose CT Reduced Effective Dose Using Computed Tomography In Orthopaedic Injury (REDUCTION) protocol. Studies from 16 selected cases were compared with 16 C-CT scans matched for age, gender and type of fracture...
December 2016: Bone & Joint Journal
https://www.readbyqxmd.com/read/27908188/polymer-gel-dosimetry-for-measuring-the-dose-near-thin-high-z-materials-irradiated-with-high-energy-photon-beams
#8
Leighton L Warmington, N Gopishankar, John H Broadhurst, Yoichi Watanabe
PURPOSE: To investigate the feasibility of three-dimensional (3D) dose measurements near thin high-Z materials placed in a water-like medium by using a polymer gel dosimeter (PGD) when the medium was irradiated with high energy photon beams. METHODS: PGD is potentially a useful tool for this application because it can record the dose around a small object made of a high-Z material in a continuous 3D medium. In this study, the authors manufactured a methacrylic acid-based normoxic PGD, nMAG...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908187/dosimetric-characterization-of-mri-only-treatment-planning-for-brain-tumors-in-atlas-based-pseudo-ct-images-generated-from-standard-t1-weighted-mr-images
#9
Benjamin Demol, Christine Boydev, Juha Korhonen, Nick Reynaert
PURPOSE: Magnetic resonance imaging (MRI)-only radiotherapy treatment planning requires accurate pseudo-CT (pCT) images for precise dose calculation. The current work introduced an atlas-based method combined with MR intensity information. pCT analyses and Monte Carlo dose calculations for intracranial stereotactic treatments were performed. METHODS: Twenty-two patients, representing 35 tumor targets, were scanned using a 3D T1-weighted MRI sequence according to the clinical protocol...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27908149/real-time-electromagnetic-seed-drop-detection-for-permanent-implants-brachytherapy-technology-overview-and-performance-assessment
#10
E Racine, G Hautvast, D Binnekamp, L Beaulieu
PURPOSE: To describe the principles and report on the performance of a novel real-time electromagnetic (EM) seed drop detection technology for permanent implants brachytherapy procedures. METHODS: A novel EM hollow needle prototype was recently developed by Philips. It possesses standard 3D tracking capability as well as a seed drop detection mechanism, both performed from a single custom built EM sensor. The detection mechanism is based on the magnetic permeability changes in the sensor as the seeds pass through...
December 2016: Medical Physics
https://www.readbyqxmd.com/read/27907861/in-situ-time-lapse-study-of-extracellular-polymeric-substance-discharge-in-streptococcus-mutans-biofilm
#11
Bernard Haochih Liu, Li-Chieh Yu
Streptococcus mutans is one of the main pathogens that cause tooth decay. By metabolizing carbohydrates, S. mutans emits extracellular polymeric substance (EPS) that adheres to the tooth surface and forms layers of biofilm. Periodontal disease occurs due to the low pH environment created by S. mutans biofilm, and such an acidic environment gradually erodes tooth enamel. Since the existence of EPS is essential in the formation of biofilm, the in-situ investigation of its generation and distribution in real time is the key to the control and suppression of S...
November 24, 2016: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/27906309/spiral-phase-mask-shadow-imaging-for-3d-measurement-of-flow-fields
#12
Martin Teich, Michael Mattern, Jeremy Sturm, Lars Büttner, Jürgen W Czarske
Particle tracking velocimetry (PTV) is a valuable tool for microfluidic analysis. Especially mixing processes and the environmental interaction of fluids on a microscopic scale are of particular importance for pharmaceutical and biomedical applications. However, currently applied techniques suffer from the lag of instantaneous depth information. Here we present a scan-free, shadow-imaging PTV-technique for 3D trajectory and velocity measurement of flow fields in micro-channels with 2 µm spatial resolution...
November 28, 2016: Optics Express
https://www.readbyqxmd.com/read/27905111/depth-enhancement-of-3d-microscopic-living-cell-image-using-incoherent-fluorescent-digital-holography
#13
L T Bang, H Y Wu, Y Zhao, E G Kim, N Kim
Multilayer images of living cells are typically obtained using confocal or multiphoton microscopy. However, limitations on the distance between consecutive scan layers hinder high-resolution three-dimensional reconstruction, and scattering strongly degrades images of living cell components. Consequently, when overlapping information from different layers is focused on a specific point in the camera, this causes uncertainty in the depiction of the cell components. We propose a method that combines the Fresnel incoherent correlation holography and a depth-of-focus reduction algorithm to enhance the depth information of three-dimensional cell images...
December 1, 2016: Journal of Microscopy
https://www.readbyqxmd.com/read/27903406/morphology-of-the-posteromedial-fragment-in-pertrochanteric-fractures-a-three-dimensional-computed-tomography-analysis
#14
Gaurav Sharma, Kiran Kumar Gn, Kavin Khatri, Ravijot Singh, Shivanand Gamanagatti, Vijay Sharma
BACKGROUND: In this study we describe the morphology of the posteromedial fragment in pertrochanteric fractures using 3D CT scans and answer two questions 1) Do differences exist between the 3D CT appearances of posteromedial fragments and the depictions made in the AO classification 2) Does the posteromedial fragment affect stability in pertrochanteric fractures, in terms of fracture collapse? METHODS: Preoperative CT scans of eight 31-A1 and fifty 31-A2 fractures were analysed...
November 17, 2016: Injury
https://www.readbyqxmd.com/read/27903193/three-dimensional-assessment-of-the-effects-of-high-density-embolization-material-on-the-absorbed-dose-in-the-target-for-gamma-knife-radiosurgery-of-arteriovenous-malformations
#15
Yoichi Watanabe, Divyajot Sandhu, Leighton Warmington, Sean Moen, Ramachandra Tummala
OBJECTIVE Arteriovenous malformation (AVM) is an intracranial vascular disorder. Gamma Knife radiosurgery (GKRS) is used in conjunction with intraarterial embolization to eradicate the nidus of AVMs. Clinical results indicate that patients with prior embolization tend to gain less benefit from GKRS. The authors hypothesized that this was partly caused by dosimetric deficiency. The actual dose delivered to the target may be smaller than the intended dose because of increased photon attenuation by high-density embolic materials...
December 2016: Journal of Neurosurgery
https://www.readbyqxmd.com/read/27901555/osteoblast-seeded-bioglass-gelatin-nanocomposite-a-promising-bone-substitute-in-critical-size-calvarial-defect-repair-in-rat
#16
Behrooz Johari, Mehdi Kadivar, Shirin Lak, Mazaher Gholipourmalekabadi, Aleksandra M Urbanska, Masoud Mozafari, Maryam Ahmadzadehzarajabad, Asaad Azarnezhad, Samane Afshari, Jamil Zargan, Saeid Kargozar
INTRODUCTION: Amid the plethora of methods to repair critical bone defects, there is no one perfect approach. In this study, we sought to evaluate a potent 3-dimensional (3D) bioactive SiO2-CaO-P2O5 glasses (bioglass)/gelatin (gel) scaffold for its biocompatibility by seeding cells as well as for its regenerative properties by animal implantation. METHODS: Osteoblast cells were seeded onto nanocomposite scaffolds to investigate the process of critical-size calvarial defect via new bone formation...
November 29, 2016: International Journal of Artificial Organs
https://www.readbyqxmd.com/read/27900618/3d-carbon-nanofiber-microelectrode-arrays-fabricated-by-plasma-assisted-pyrolysis-to-enhance-sensitivity-and-stability-of-real-time-dopamine-detection
#17
Wenwen Yi, Yuanyuan Yang, Parastoo Hashemi, Mark Ming-Cheng Cheng
In this paper, we have fabricated 3D carbon nanofiber microelectrode arrays (MEAs) with highly reproducible and rich chemical surface areas for fast scan cyclic voltammetry (FSCV). Carbon nanofibers are created from negative photoresist by a new process called dual O2 plasma-assisted pyrolysis. The proposed approach significantly improves film adhesion and increases surface reactivity. We showcase our sensor's compatibility with FSCV analysis by demonstrating highly sensitive and stable FSCV dopamine measurements on a prototype 4-channel array...
December 2016: Biomedical Microdevices
https://www.readbyqxmd.com/read/27900518/the-reconstruction-algorithm-used-for-68-ga-psma-hbed-cc-pet-ct-reconstruction-significantly-influences-the-number-of-detected-lymph-node-metastases-and-coeliac-ganglia
#18
Thomas Krohn, Anita Birmes, Oliver H Winz, Natascha I Drude, Felix M Mottaghy, Florian F Behrendt, Frederik A Verburg
PURPOSE: To investigate whether the numbers of lymph node metastases and coeliac ganglia delineated on [(68)Ga]PSMA-HBED-CC PET/CT scans differ among datasets generated using different reconstruction algorithms. METHODS: Data were constructed using the BLOB-OS-TF, BLOB-OS and 3D-RAMLA algorithms. All reconstructions were assessed by two nuclear medicine physicians for the number of pelvic/paraaortal lymph node metastases as well the number of coeliac ganglia. Standardized uptake values (SUV) were also calculated in different regions...
November 29, 2016: European Journal of Nuclear Medicine and Molecular Imaging
https://www.readbyqxmd.com/read/27900270/three-dimensional-reconstructed-magnetic-resonance-scans-accuracy-in-identifying-and-defining-knee-meniscal-tears
#19
Neil Kruger, Eugene McNally, Sami Al-Ali, Raj Rout, Jonathan L Rees, Andrew J Price
AIM: To determine whether three-dimensional (3D) reconstruction from conventional magnetic resonance imaging (MRI) is able to accurately detect a meniscal tear, and define the configuration. METHODS: Thirty-three patients' 3T MRI scan data were collected and sagittal uni-planar 3D reconstructions performed from the preoperative MRI. There were 24 meniscal tears in 24 patients, and nine controls. All patients had arthroscopic corroboration of MRI findings. Two independent observers prospectively reported on all 33 reconstructions...
November 18, 2016: World Journal of Orthopedics
https://www.readbyqxmd.com/read/27898749/-dosimetric-comparison-of-different-techniques-for-external-beam-accelerated-partial-breast-irradiation
#20
Gábor Stelczer, Tibor Major, Norbert Mészáros, Csaba Polgár, Csilla Pesznyák
The aim of this article is to evaluate and compare four different radiotherapy techniques of accelerated partial breast irradiation (APBI) considering planning quality, dosimetric and practical aspects. The investigated techniques are three dimensional conformal radiotherapy (3D-CRT), "step and shoot" (SS) and "sliding window" (SW) intensity-modulated radiotherapy, intensity-modulated arc therapy (RA). CT scans of 10 patients previously treated with APBI were selected for the study. Surgical clips were placed on the borders of the tumour bed during breast conserving surgery...
November 29, 2016: Magyar Onkologia
keyword
keyword
71155
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"