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Proceedings of SPIE

Albert Ngo, Kenneth H Chan, Oanh Le, Jacob C Simon, Daniel Fried
Recent studies have shown that near-IR (NIR) imaging methods such as NIR reflectance can be used to image lesions on proximal surfaces, and optical coherence tomography (OCT) can be used to measure the depth of those lesions below the tooth surface. These imaging modalities can be used to acquire high contrast images of demineralized tooth surfaces, and 2-D and 3-D images can be extracted from this data. At NIR wavelengths longer than 1200-nm, there is no interference from stains and the contrast is only due to the increased light scattering of the demineralization...
January 2018: Proceedings of SPIE
Jacob C Simon, Donald A Curtis, Cynthia L Darling, Daniel Fried
In vivo and in vitro studies have demonstrated that near-infrared (NIR) light at λ=1300-1700-nm can be used to acquire high contrast images of enamel demineralization without interference of stains. The objective of this study was to determine if a relationship exists between the NIR image contrast of occlusal lesions and the depth of the lesion. Extracted teeth with varying amounts of natural occlusal decay were measured using a multispectral-multimodal NIR imaging system which captures λ=1300-nm occlusal transillumination, and λ=1500-1700-nm cross-polarized reflectance images...
January 2018: Proceedings of SPIE
Shibani Singh, Anant Srivastava, Liang Mi, Richard J Caselli, Kewei Chen, Dhruman Goradia, Eric M Reiman, Yalin Wang
Fluorodeoxyglucose (FDG) positron emission tomography (PET) measures the decline in the regional cerebral metabolic rate for glucose, offering a reliable metabolic biomarker even on presymptomatic Alzheimer's disease (AD) patients. PET scans provide functional information that is unique and unavailable using other types of imaging. However, the computational efficacy of FDG-PET data alone, for the classification of various Alzheimers Diagnostic categories, has not been well studied. This motivates us to correctly discriminate various AD Diagnostic categories using FDG-PET data...
October 2017: Proceedings of SPIE
Francesco Ceccarelli, Angelo Gulinatti, Ivan Labanca, Ivan Rech, Massimo Ghioni
In recent years the development of Single-Photon Avalanche Diodes (SPADs) had a big impact on single-photon counting applications requiring high-performance detectors in terms of Dark Count Rate (DCR), Photon Detection Efficiency (PDE), afterpulsing probability, etc. Among these, it is possible to find applications in single-molecule fluorescence spectroscopy that suffer from long-time measurements. In these cases SPAD arrays can be a solution in order to shorten the measurement time, thanks to the high grade of parallelism they can provide...
April 24, 2017: Proceedings of SPIE
Sungmin Hong, James Fishbaugh, Morteza Rezanejad, Kaleem Siddiqi, Hans Johnson, Jane Paulsen, Eun Young Kim, Guido Gerig
Modeling subject-specific shape change is one of the most important challenges in longitudinal shape analysis of disease progression. Whereas anatomical change over time can be a function of normal aging; anatomy can also be impacted by disease related degeneration. Shape changes to anatomy may also be affected by external structural changes from neighboring structures, which may cause non-linear pose variations. In this paper, we propose a framework to analyze disease related shape changes by coupling extrinsic modeling of the ambient anatomical space via spatiotemporal deformations with intrinsic shape properties from medial surface analysis...
April 2017: Proceedings of SPIE
Adora M DSouza, Anas Z Abidin, Axel Wismüller
Infection of the brain by the Human Immunodeficiency Virus (HIV) causes irreversible damage to the synaptic connections resulting in cognitive impairment. Patients with HIV infection, showing signs of impairment in multiple cognitive domains, as assessed by neuropsychological testing, are said to exhibit symptoms of HIV Associated Neurocognitive Disorder (HAND). In this study, we use resting-state functional MRI (fMRI) data to distinguish between healthy subjects and subjects with symptoms of HAND. To this end, we first establish a measure of interaction between pairs of regional time-series by quantifying their non-linear functional connectivity using Mutual Connectivity Analysis (MCA)...
March 13, 2017: Proceedings of SPIE
A Ferrero, R Gutjahr, A Henning, S Kappler, A Halaweish, D Abdurakhimova, Z Peterson, J Montoya, S Leng, C McCollough
In addition to the standard-resolution (SR) acquisition mode, a high-resolution (HR) mode is available on a research photon-counting-detector (PCD) whole-body CT system. In the HR mode each detector consists of a 2x2 array of 0.225 mm × 0.225 mm subpixel elements. This is in contrast to the SR mode that consists of a 4x4 array of the same sub-elements, and results in 0.25 mm isotropic resolution at iso-center for the HR mode. In this study, we quantified ex vivo the capabilities of the HR mode to characterize renal stones in terms of morphology and mineral composition...
March 9, 2017: Proceedings of SPIE
Jean Noel, Juan C Prieto, Martin Styner
Functional Analysis of Diffusion Tensor Tract Statistics (FADTTS) is a toolbox for analysis of white matter (WM) fiber tracts. It allows associating diffusion properties along major WM bundles with a set of covariates of interest, such as age, diagnostic status and gender, and the structure of the variability of these WM tract properties. However, to use this toolbox, a user must have an intermediate knowledge in scripting languages (MATLAB). FADTTSter was created to overcome this issue and make the statistical analysis accessible to any non-technical researcher...
March 2017: Proceedings of SPIE
Danaële Puechmaille, Martin Styner, Juan C Prieto
Cloud based Interactive Visualization of Tractography Brain Connectome (CIVILITY) is an interactive visualization tool of brain connectome in the cloud. This application submits tasks to remote computing grids were the CIVILITY-tractography pipeline is deployed. The application will list the running tasks for the user and once a task is completed the brain connectome is visualized using Hierarchical Edge Bundling. The analysis pipeline uses FSL tools (bedpostx and probtrackx2) to generate a triangular matrix indicating the connectivity strength between different regions in the brain...
March 2017: Proceedings of SPIE
Xia Huang, Chunqiang Li, Chuan Xiao, Wenqing Sun, Wei Qian
The temporal focusing two-photon microscope (TFM) is developed to perform depth resolved wide field fluorescence imaging by capturing frames sequentially. However, due to strong nonignorable noises and diffraction rings surrounding particles, further researches are extremely formidable without a precise particle localization technique. In this paper, we developed a fully-automated scheme to locate particles positions with high noise tolerance. Our scheme includes the following procedures: noise reduction using a hybrid Kalman filter method, particle segmentation based on a multiscale kernel graph cuts global and local segmentation algorithm, and a kinematic estimation based particle tracking method...
March 2017: Proceedings of SPIE
Anas Z Abidin, John Jameson, Robert Molthen, Axel Wismüller
Few studies have analyzed the microstructural properties of bone in cases of Osteogenenis Imperfecta (OI), or 'brittle bone disease'. Current approaches mainly focus on bone mineral density measurements as an indirect indicator of bone strength and quality. It has been shown that bone strength would depend not only on composition but also structural organization. This study aims to characterize 3D structure of the cortical bone in high-resolution micro CT images. A total of 40 bone fragments from 28 subjects (13 with OI and 15 healthy controls) were imaged using micro tomography using a synchrotron light source (SRμCT)...
March 2017: Proceedings of SPIE
Anas Z Abidin, Udaysankar Chockanathan, Adora M DSouza, Matilde Inglese, Axel Wismüller
Clinically Isolated Syndrome (CIS) is often considered to be the first neurological episode associated with Multiple sclerosis (MS). At an early stage the inflammatory demyelination occurring in the CNS can manifest as a change in neuronal metabolism, with multiple asymptomatic white matter lesions detected in clinical MRI. Such damage may induce topological changes of brain networks, which can be captured by advanced functional MRI (fMRI) analysis techniques. We test this hypothesis by capturing the effective relationships of 90 brain regions, defined in the Automated Anatomic Labeling (AAL) atlas, using a large-scale Granger Causality (lsGC) framework...
March 2017: Proceedings of SPIE
Mark Sak, Neb Duric, Peter Littrup, Mark Sherman, Gretchen Gierach
Ultrasound tomography (UST) is an emerging modality that can offer quantitative measurements of breast density. Recent breakthroughs in UST image reconstruction involve the use of a waveform reconstruction as opposed to a ray-based reconstruction. The sound speed (SS) images that are created using the waveform reconstruction have a much higher image quality. These waveform images offer improved resolution and contrasts between regions of dense and fatty tissues. As part of a study that was designed to assess breast density changes using UST sound speed imaging among women undergoing tamoxifen therapy, UST waveform sound speed images were then reconstructed for a subset of participants...
March 2017: Proceedings of SPIE
Bogdan Dzyubak, Kevin J Glaser, Armando Manduca, Richard L Ehman
Magnetic Resonance Elastography (MRE) is a phase-contrast MRI technique which calculates quantitative stiffness images, called elastograms, by imaging the propagation of acoustic waves in tissues. It is used clinically to diagnose liver fibrosis. Automated analysis of MRE is difficult as the corresponding MRI magnitude images (which contain anatomical information) are affected by intensity inhomogeneity, motion artifact, and poor tissue- and edge-contrast. Additionally, areas with low wave amplitude must be excluded...
March 2017: Proceedings of SPIE
J Goerres, M Jacobson, A Uneri, T De Silva, M Ketcha, S Reaungamornrat, S Vogt, G Kleinszig, J-P Wolinsky, G Osgood, J H Siewerdsen
Pelvic Kirschner wire (K-wire) insertion is a challenging surgical task requiring interpretation of complex 3D anatomical shape from 2D projections (fluoroscopy) and delivery of device trajectories within fairly narrow bone corridors in proximity to adjacent nerves and vessels. Over long trajectories (~10-25 cm), K-wires tend to curve (deform), making conventional rigid navigation inaccurate at the tip location. A system is presented that provides accurate 3D localization and guidance of rigid or deformable surgical devices ("components" - e...
March 2017: Proceedings of SPIE
Q Cao, M Brehler, A Sisniega, J W Stayman, J Yorkston, J H Siewerdsen, W Zbijewski
PURPOSE: CMOS x-ray detectors offer small pixel sizes and low electronic noise that may support the development of novel high-resolution imaging applications of cone-beam CT (CBCT). We investigate the effects of CsI scintillator thickness on the performance of CMOS detectors in high resolution imaging tasks, in particular in quantitative imaging of bone microstructure in extremity CBCT. METHODS: A scintillator thickness-dependent cascaded systems model of CMOS x-ray detectors was developed...
March 2017: Proceedings of SPIE
S Ouadah, M Jacobson, J W Stayman, T Ehtiati, C Weiss, J H Siewerdsen
PURPOSE: This work applies task-driven optimization to the design of non-circular orbits that maximize imaging performance for a particular imaging task. First implementation of task-driven imaging on a clinical robotic C-arm system is demonstrated, and a framework for orbit calculation is described and evaluated. METHODS: We implemented a task-driven imaging framework to optimize orbit parameters that maximize detectability index d'. This framework utilizes a specified Fourier domain task function and an analytical model for system spatial resolution and noise...
March 2017: Proceedings of SPIE
M W Jacobson, M Ketcha, A Uneri, J Goerres, T De Silva, S Reaungamornrat, S Vogt, G Kleinszig, J H Siewerdsen
PURPOSE: Traditional BB-based geometric calibration methods for cone-beam CT (CBCT) rely strongly on foreknowledge of the scan trajectory shape. This is a hindrance to the implementation of variable trajectory CBCT systems, normally requiring a dedicated calibration phantom or software algorithm for every scan orbit of interest. A more flexible method of calibration is proposed here that accommodates multiple orbit types - including strongly noncircular trajectories - with a single phantom and software routine...
March 2017: Proceedings of SPIE
Gabrielle A Murashova, Christopher A Mancuso, Sanae Sakami, Krzysztof Palczewski, Grazyna Palczewska, Marcos Dantus
In this work, we present all epi-direction detected images of an unstained mouse retina using multiphoton microscopy with a sub-50 fs Yb-fiber laser centered at 1.07 μm. This wavelength is particularly interesting as the fundamental wavelength is transparent to the anterior segment of the eye and the higher harmonics are above DNA-damaging UV wavelengths. We present a characterization of the multimodal signals emitted from the different retinal layers, as well as from the choroid and the sclera. By characterizing native multiphoton signals from the retina, we move closer to having Yb-fiber considered for in vivo diagnosis of retinal disease through multiphoton microscopy as well as for corrective therapies...
March 2017: Proceedings of SPIE
Wonsang You, Nickie Andescavage, Zungho Zun, Catherine Limperopoulos
Intravoxel incoherent motion (IVIM) magnetic resonance imaging is an emerging non-invasive technique that has been recently applied to quantify in vivo global placental perfusion. We propose a robust semi-automated method for segmenting the placenta into fetal and maternal compartments from IVIM data, using a multi-label image segmentation algorithm called 'GrowCut'. Placental IVIM data were acquired on a 1.5T scanner from 16 healthy pregnant women between 21-37 gestational weeks. The voxel-wise perfusion fraction was then estimated after non-rigid image registration...
March 2017: Proceedings of SPIE
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