The impact of spectral filtration on image quality in micro-CT system

Limited-angle iterative reconstruction (LAIR) reduces the radiation dose required for computed tomography (CT) imaging by decreasing the range of the projection angle. We developed an image-quality-based stopping-criteria method with a flexible and innovative instrument design that, when combined with LAIR, provides the image quality of a conventional CT system. This study describes the construction of different scan acquisition protocols for micro-CT system applications. Fully-sampled Feldkamp (FDK)-reconstructed images were used as references for comparison to assess the image quality produced by these tested protocols. The insufficient portions of a sinogram were inpainted by applying a context encoder (CE), a type of generative adversarial network, to the LAIR process. The context image was passed through an encoder to identify features that were connected to the decoder using a channel-wise fully-connected layer. Our results evidence the excellent performance of this novel approach. Even when we reduce the radiation dose by 1/4, the iterative-based LAIR improved the full-width half-maximum, contrast-to-noise and signal-to-noise ratios by 20% to 40% compared to a fully-sampled FDK-based reconstruction. Our data support that this CE-based sinogram completion method enhances the efficacy and efficiency of LAIR and that would allow feasibility of limited angle reconstruction.

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Effect of projection number on slice image quality of micro-CT system

10.1117/12.833053 ◽

2009 ◽

Author(s):

Zheng Fang ◽

Hui Gong ◽

Guang Yang ◽

Tianxu Zhang

Keyword(s):

Image Quality ◽

Micro Ct ◽

Ct System ◽

Slice Image

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The Study of Reconstruction Image Quality Resulting from Geometric Error in Micro-CT System

2010 4th International Conference on Bioinformatics and Biomedical Engineering ◽

10.1109/icbbe.2010.5514749 ◽

2010 ◽

Cited By ~ 1

Author(s):

Dongxing Xi ◽

Jianbao Gui ◽

Jing Zou ◽

Junyan Rong ◽

Zhanli Hu ◽

...

Keyword(s):

Image Quality ◽

Geometric Error ◽

Micro Ct ◽

Reconstruction Image ◽

Ct System

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P‐13.5: The impact of Gate Loading on Image Quality for large & middle size AM‐OLED display devices

SID Symposium Digest of Technical Papers ◽

10.1002/sdtp.14581 ◽

2021 ◽

Vol 52 (S1) ◽

pp. 643-646

Author(s):

Yang Guobo ◽

Qiu Haijun ◽

Huang Weiyun ◽

Yang Yuqing ◽

Long Yue ◽

...

Keyword(s):

Image Quality ◽

Display Devices ◽

The Impact ◽

Oled Display

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Modeling and image quality enhancement for dynamic compressive imaging system

Journal of Algorithms & Computational Technology ◽

10.1177/17483026211008098 ◽

2021 ◽

Vol 15 ◽

pp. 174830262110080

Author(s):

Changjun Zha* ◽

Qian Zhang* ◽

Huimin Duan

Keyword(s):

Image Quality ◽

Imaging System ◽

Quality Enhancement ◽

Target Image ◽

Compressive Imaging ◽

Image Quality Enhancement ◽

System A ◽

Single Column ◽

The Impact

Traditional single-pixel imaging systems are aimed mainly at relatively static or slowly changing targets. When there is relative motion between the imaging system and the target, sizable deviations between the measurement values and the real values can occur and result in poor image quality of the reconstructed target. To solve this problem, a novel dynamic compressive imaging system is proposed. In this system, a single-column digital micro-mirror device is used to modulate the target image, and the compressive measurement values are obtained for each column of the image. Based on analysis of the measurement values, a new recovery model of dynamic compressive imaging is given. Differing from traditional reconstruction results, the measurement values of any column of vectors in the target image can be used to reconstruct the vectors of two adjacent columns at the same time. Contingent upon characteristics of the results, a method of image quality enhancement based on an overlapping average algorithm is proposed. Simulation experiments and analysis show that the proposed dynamic compressive imaging can effectively reconstruct the target image; and that when the moving speed of the system changes within a certain range, the system reconstructs a better original image. The system overcomes the impact of dynamically changing speeds, and affords significantly better performance than traditional compressive imaging.

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Evaluation of Organ Dose and Image Quality Metrics of Pediatric CT Chest-Abdomen-Pelvis (CAP) Examination: An Anthropomorphic Phantom Study

Applied Sciences ◽

10.3390/app11052047 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2047

Author(s):

Nor Azura Muhammad ◽

Zunaide Kayun ◽

Hasyma Abu Hassan ◽

Jeannie Hsiu Ding Wong ◽

Kwan Hoong Ng ◽

...

Keyword(s):

Image Quality ◽

Multidetector Ct ◽

Organ Dose ◽

Quality Metrics ◽

Ct Scanner ◽

Image Quality Metrics ◽

Tube Current ◽

Significant Difference ◽

Noise Ratio ◽

The Impact

The aim of this study is to investigate the impact of CT acquisition parameter setting on organ dose and its influence on image quality metrics in pediatric phantom during CT examination. The study was performed on 64-slice multidetector CT scanner (MDCT) Siemens Definition AS (Siemens Sector Healthcare, Forchheim, Germany) using various CT CAP protocols (P1–P9). Tube potential for P1, P2, and P3 protocols were fixed at 100 kVp while P4, P5, and P6 were fixed at 80 kVp with used of various reference noise values. P7, P8, and P9 were the modification of P1 with changes on slice collimation, pitch factor, and tube current modulation (TCM), respectively. TLD-100 chips were inserted into the phantom slab number 7, 9, 10, 12, 13, and 14 to represent thyroid, lung, liver, stomach, gonads, and skin, respectively. The image quality metrics, signal to noise ratio (SNR) and contrast to noise ratio (CNR) values were obtained from the CT console. As a result, this study indicates a potential reduction in the absorbed dose up to 20% to 50% along with reducing tube voltage, tube current, and increasing the slice collimation. There is no significant difference (p > 0.05) observed between the protocols and image metrics.

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Warpage Reduction of Glass Fiber Reinforced Plastic Using Microcellular Foaming Process Applied Injection Molding

Polymers ◽

10.3390/polym11020360 ◽

2019 ◽

Vol 11 (2) ◽

pp. 360 ◽

Cited By ~ 5

Author(s):

Hyun Kim ◽

Joo Sohn ◽

Youngjae Ryu ◽

Shin Kim ◽

Sung Cha

Keyword(s):

Injection Molding ◽

Glass Fiber ◽

Fiber Orientation ◽

Mechanical And Thermal Properties ◽

Micro Ct ◽

Fiber Reinforced ◽

Foaming Process ◽

Microcellular Foaming ◽

Glass Fiber Reinforced ◽

The Impact

This study analyzes the fundamental principles and characteristics of the microcellular foaming process (MCP) to minimize warpage in glass fiber reinforced polymer (GFRP), which is typically worse than that of a solid polymer. In order to confirm the tendency for warpage and the improvement of this phenomenon according to the glass fiber content (GFC), two factors associated with the reduction of the shrinkage difference and the non-directionalized fiber orientation were set as variables. The shrinkage was measured in the flow direction and transverse direction, and it was confirmed that the shrinkage difference between these two directions is the cause of warpage of GFRP specimens. In addition, by applying the MCP to injection molding, it was confirmed that warpage was improved by reducing the shrinkage difference. To further confirm these results, the effects of cell formation on shrinkage and fiber orientation were investigated using scanning electron microscopy, micro-CT observation, and cell morphology analysis. The micro-CT observations revealed that the fiber orientation was non-directional for the MCP. Moreover, it was determined that the mechanical and thermal properties were improved, based on measurements of the impact strength, tensile strength, flexural strength, and deflection temperature for the MCP.

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Dose and Image Quality Evaluation of a Dedicated Cone-Beam CT System for High-Contrast Neurologic Applications

American Journal of Roentgenology ◽

10.2214/ajr.09.2951 ◽

2010 ◽

Vol 194 (2) ◽

pp. W193-W201 ◽

Cited By ~ 33

Author(s):

Lifeng Yu ◽

Thomas J. Vrieze ◽

Michael R. Bruesewitz ◽

James M. Kofler ◽

David R. DeLone ◽

...

Keyword(s):

Image Quality ◽

Quality Evaluation ◽

Cone Beam Ct ◽

Cone Beam ◽

High Contrast ◽

Image Quality Evaluation ◽

Ct System

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The Effects of Bone Microstructure on Subsidence Risk for ALIF, LLIF, PLIF, and TLIF Spine Cages

Journal of Biomechanical Engineering ◽

10.1115/1.4042181 ◽

2019 ◽

Vol 141 (3) ◽

Cited By ~ 6

Author(s):

Vivek Palepu ◽

Melvin D. Helgeson ◽

Michael Molyneaux-Francis ◽

Srinidhi Nagaraja

Keyword(s):

Trabecular Bone ◽

Bone Quality ◽

Volume Fraction ◽

Lumbar Fusion ◽

Lumbar Vertebrae ◽

Micro Ct ◽

Cage Subsidence ◽

Maximum Subsidence ◽

Trabecular Bone Quality ◽

The Impact

Several approaches (anterior, posterior, lateral, and transforaminal) are used in lumbar fusion surgery. However, it is unclear whether one of these approaches has the greatest subsidence risk as published clinical rates of cage subsidence vary widely (7–70%). Specifically, there is limited data on how a patient's endplate morphometry and trabecular bone quality influences cage subsidence risk. Therefore, this study compared subsidence (stiffness, maximum force, and work) between anterior (ALIF), lateral (LLIF), posterior (PLIF), and transforaminal (TLIF) lumbar interbody fusion cage designs to understand the impact of endplate and trabecular bone quality on subsidence. Forty-eight lumbar vertebrae were imaged with micro-ct to assess trabecular microarchitecture. micro-ct images of each vertebra were then imported into image processing software to measure endplate thickness (ET) and maximum endplate concavity depth (ECD). Generic ALIF, LLIF, PLIF, and TLIF cages made of polyether ether ketone were implanted on the superior endplates of all vertebrae and subsidence testing was performed. The results indicated that TLIF cages had significantly lower (p < 0.01) subsidence stiffness and maximum subsidence force compared to ALIF and LLIF cages. For all cage groups, trabecular bone volume fraction was better correlated with maximum subsidence force compared to ET and concavity depth. These findings highlight the importance of cage design (e.g., surface area), placement on the endplate, and trabecular bone quality on subsidence. These results may help surgeons during cage selection for lumbar fusion procedures to mitigate adverse events such as cage subsidence.

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