Novel method for selecting slices of the same cross-sectional view from digital tomosynthesis for monitoring posterior spinal instrumentation

2021 ◽  
Vol 92 ◽  
pp. 183-188
Author(s):  
Eriko Okano ◽  
Yuki Hara ◽  
Atsuo Ito ◽  
Kentaro Mataki ◽  
Yasukazu Totoki ◽  
...  
Keyword(s):  
Spinal Instrumentation ◽  
Digital Tomosynthesis ◽  
Cross Sectional ◽  
Novel Method

scholarly journals Development of a Quantitative Method to Evaluate Pedicle Screw Loosening After Spinal Instrumentation Using Digital Tomosynthesis

2021 ◽  
Author(s):  
Kentaro Mataki ◽  
Yuki Hara ◽  
Eriko Okano ◽  
Katsuya Nagashima ◽  
Hiroshi Noguchi ◽  
...  
Keyword(s):  
Pedicle Screw ◽  
Spinal Instrumentation ◽  
Pedicle Screws ◽  
Posterior Spinal Fusion ◽  
Standing Position ◽  
Digital Tomosynthesis ◽  
Cross Sectional ◽  
Tomographic Images ◽  
Spinal Fusion Surgery ◽  
Displacement Angle

Abstract BackgroundIn general, the diagnosis of pedicle screw (PS) loosening is evaluated qualitatively based on the presence of a radiolucent area around the implant wider than 1 mm on plain radiographs and computed tomography (CT). Digital tomosynthesis is a novel imaging technology that can acquire reconstructed tomographic images of patients in different postures with relatively low radiation. In this study, PS loosening is evaluated quantitatively by measuring the PS displacement angle in the vertebrae using digital tomosynthesis. MethodsWe evaluated 41 patients who underwent posterior spinal fusion surgery using PS. The 72 pedicle screws at the cranial end of the fused segments were evaluated. The patients were divided in two groups, one with PS loosening (7 patients, 12 screws) and the other without PS loosening (34 patients, 60 screws), based on conventional CT findings. All patients underwent tomosynthesis in two different postures during a single CT session. ResultsThe displacement angles of the PS in patients in a lying position and in a standing position were measured using selected slices of the same cross-sectional view from digital tomosynthesis. The displacement angle was significantly greater in the PS loosening group (5.7°) than in the group without PS loosening (0.6°) (p＜0.01). Based on the ROC analysis, the optimal cut-off value of the PS displacement angle for identification of loosened screws was 1.7° with a sensitivity of 100% and specificity of 93% (AUC=0.98). ConclusionsThis new method using digital tomosynthesis has the potential to aid diagnosis of PS loosening quantitatively and more accurately than conventional evaluations.

Customized Circuit Interconnect and Repair by Laser Seeding and Constriction-Induced Plating.

1990 ◽  
Vol 203 ◽  
Author(s):  
Julian P. Partridge ◽  
C. Julian Chen
Keyword(s):  
Equilibrium Potential ◽  
Palladium Acetate ◽  
Process Window ◽  
Acetate Solution ◽  
Cross Sectional ◽  
Mechanical And Electrical Properties ◽  
Copper Electrolyte ◽  
Ion Laser ◽  
Novel Method ◽  
Current Densities

ABSTRACTA novel method has been developed for producing customized copper interconnections on thermally-sensitive substrates by laser seeding followed by constrictioninduced electroplating. A polyimide, polytetrafluoroethylene, or glass-epoxy substrate is first sprayed with palladium acetate solution. 500 nm thick palladium interconnects are then formed using a 514 nm argon ion laser (10 mW - 50 mW) to selectively pyrolyze the acetate film. After cleaning, the part is immersed in an acid copper electrolyte and an alternating current (0.1 Amp - 2.0 Amp) passed through the palladium seed. Joule heating produces a cathodic shift in the equilibrium potential (dε0/dT = 0.63 mV/degree) which causes electrodeposition of copper along the seeded connection.Cross-sectional microscopy and electrochemical polarization studies show that local plating current densities of 10 mA/cm2 produce 1000 εm × 25 εm × 10 εm line geometries exhibiting excellent mechanical and electrical properties. The large process window suggests that customization and repair on lincwidths below 1 mil (25 εm) should be achievable routinely.

Characterization of pulsed laser deposited MoS2 by transmission electron microscopy

1993 ◽  
Vol 8 (11) ◽  
pp. 2933-2941 ◽  
Author(s):  
S.D. Walek ◽  
M.S. Donley ◽  
J.S. Zabinski ◽  
V.J. Dyhouse
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Solid Phase ◽  
Analytical Electron Microscopy ◽  
Pulsed Laser ◽  
Cross Sectional ◽  
Aerospace Applications ◽  
Transmission Electron ◽  
Novel Method

Molybdenum disulfide is a technologically important solid phase lubricant for vacuum and aerospace applications. Pulsed laser deposition of MoS2 is a novel method for producing fully dense, stoichiometric thin films and is a promising technique for controlling the crystallographic orientation of the films. Transmission electron microscopy (TEM) of self-supporting thin films and cross-sectional TEM samples was used to study the crystallography and microstructure of pulsed laser deposited films of MoS2. Films deposited at room temperature were found to be amorphous. Films deposited at 300 °C were nanocrystalline and had the basal planes oriented predominately parallel to the substrate within the first 12–15 nm of the substrate with an abrupt upturn into a perpendicular (edge) orientation farther from the substrate. Spherically shaped particles incorporated in the films from the PLD process were found to be single crystalline, randomly oriented, and less than about 0.1 μm in diameter. A few of these particles, observed in cross section, had flattened bottoms, indicating that they were molten when they arrived at the surface of the growing film. Analytical electron microscopy (AEM) was used to study the chemistry of the films. The x-ray microanalysis results showed that the films have the stoichiometry of cleaved single crystal MoS2 standards.

A Novel Method for the Measurement of Slight Wear

2013 ◽  
Vol 750-752 ◽  
pp. 1987-1991
Author(s):  
Jian Hua Yang ◽  
Xing Jian Ma ◽  
Lu Fei Rong ◽  
Bo Liu ◽  
Jia Yan Yu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Measurement Accuracy ◽  
Processing Technology ◽  
Wear Testing ◽  
Cross Sectional ◽  
Speed Up ◽  
Novel Method ◽  
Pretreatment Conditions ◽  
Weighing Method

The characterization of surface wear resistance of materials usually relies on the measurement of slight wear. There are two obvious shortcomings for weighing method. In order to improve the measurement accuracy, a more intuitive and reliable method for quantitative measurement of slight wear, interference microscope method, has be given. Higher accuracy (the order of micrometer) can be achieved using the interferometry for the measurement of slight wear. The results show that the masking processing technology can ensure that all samples for wear testing and other analysis are obtained under the same pretreatment conditions and vacuum processing conditions, speed up the commercialization of processing technology, and comparing the cross-sectional areas of wear scars is a correct way to characterize the wear resistance of different zones.

scholarly journals Novel case-control observational method for assessing effectiveness of red-light cameras

2017 ◽  
Vol 44 (6) ◽  
pp. 407-416 ◽  
Author(s):  
Amal Jasem Abdulsalam ◽  
Dane Rowlands ◽  
Said M. Easa ◽  
Abd El Halim O. Abd El Halim
Keyword(s):  
Empirical Bayes ◽  
Red Light ◽  
Control Group ◽  
Cross Sectional ◽  
Specific Criterion ◽  
Red Light Cameras ◽  
Empirical Bayes Methods ◽  
Novel Method ◽  
Conventional Methods ◽  
Different Characteristics

Conventional methods for estimating the effect of an intervention suffer from selection bias, where the units that receive the treatment have different characteristics from those in the control group. This paper proposes a novel method that provides a specific criterion for selecting the control group. The method, called propensity score matching (PSM), was applied to the evaluation of red-light cameras (RLC) and its performance was compared with conventional cross-sectional and empirical Bayes methods. The application was performed using field data from the City of Ottawa involving 30 RLC intersections and 89 non-camera intersections observed for a period of 15 years. All three methods yielded fairly consistent results, indicating an increase in property damage collisions and a decrease in injury and fatal collisions. Given the strong theoretical basis of the PSM method and its ability to produce a more stable and reliable estimator, the method is recommended as a viable alternative to the conventional methods.

Image Distortion Compensation by Using a Polynomial Model in an X-Ray Digital Tomosynthesis System

2005 ◽  
Vol 297-300 ◽  
pp. 2034-2039 ◽  
Author(s):  
J.Y. Kim ◽  
J.S. Yoon
Keyword(s):  
Flip Chip ◽  
Image Intensifier ◽  
Industrial Applications ◽  
Image Distortion ◽  
Polynomial Model ◽  
Digital Tomosynthesis ◽  
Cross Sectional ◽  
Distortion Compensation ◽  
X Ray ◽  
Cross Sectional Imaging

X-ray technology has been widely used in a number of industrial applications for monitoring and inspecting inner defects which can hardly be found by normal vision systems as a ball grid array (BGA) or a flip chip array (FCA). Digital tomosynthesis (DT) is one of the most useful X-ray cross-sectional imaging methods for PCB inspection, and it usually uses an X-ray image intensifier. However, the image intensifier distorts X-ray images severely both of shape and intensity. This distortion breaks the correspondences between those images and prevents us from acquiring accurate cross-section images. Therefore, image distortion compensation is one of the most important issues in realizing a DT system. In this paper, an image distortion compensation method for an X-ray DT system is presented. It is to use a general distortion polynomial model on two dimensional plane that can cope with arbitrary, complex and various forms of distortion. Experimental results show a great improvement in compensation speed and accuracy.

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