scholarly journals Interscan measurement error of knee cartilage thickness and projected cartilage area ratio at 9 regions and 45 subregions by fully automatic three-dimensional MRI analysis

2021 ◽  
pp. 109700
Author(s):  
Ichiro Sekiya ◽  
Yuji Kohno ◽  
Akinobu Hyodo ◽  
Hisako Katano ◽  
Keiichiro Komori ◽  
...  
Keyword(s):  
Measurement Error ◽  
Three Dimensional ◽  
Cartilage Thickness ◽  
Area Ratio ◽  
Knee Cartilage ◽  
Fully Automatic

Fully automatic three-dimensional MRI analysis for the cartilage and meniscus of the knee: Kanagawa Knee Study

2020 ◽  
Author(s):  
Hayato Aoki ◽  
Nobutake Ozeki ◽  
Hisako Katano ◽  
Akinobu Hyodo ◽  
Junpei Matsuda ◽  
...  
Keyword(s):  
Lateral Meniscus ◽  
Three Dimensional ◽  
Cross Sectional Study ◽  
Cartilage Volume ◽  
Cartilage Thickness ◽  
Similarity Coefficients ◽  
Cross Sectional ◽  
Coverage Ratio ◽  
Fully Automatic ◽  
Meniscus Extrusion

Abstract Objective We have developed a fully automatic three-dimensional MRI analysis software that measures the projected cartilage area ratio (PCAR) to allow for the quantification of the cartilage in the knee. Our objectives for this cross-sectional study were to verify our software’s accuracy and to quantify cartilage and meniscus extrusion. We also examined which cartilage quantification was most affected by age and analyzed the relationship between PCAR and meniscus extrusion. Methods 108 subjects were selected for training, and Dice similarity coefficients were determined from 5 other subjects. This study included 561 subjects between 30–70 years of age. From their knee MRI data, we quantified cartilage thickness, cartilage volume, and PCAR (0.0–1.5 mm) in four regions, including the medial tibial (MT) cartilage. Furthermore, each region was divided into nine subregions. The medial central (mc) subregion was also analyzed. As a quantification for meniscus extrusion, the medial meniscus coverage ratio (MMCR) was also investigated. Results Dice similarity coefficients were 0.911 and 0.892 for the femoral and tibial cartilage and 0.916 and 0.891 for the medial and lateral meniscus. Among 48 cartilage quantifications, the highest absolute value of the correlation coefficient with age was mcMT PCAR 1.0 mm in females and mcMT cartilage thickness in males. In females, mcMT PCAR 1.0 mm was correlated with MMCR, although MMCR was not correlated with age. In males, mcMT PCAR 0.0 mm was correlated with MMCR. Conclusions Our software showed high segmentation accuracy and provided numerous quantifications of cartilage related to age and meniscus extrusion.

scholarly journals Interscan measurement error in measurements of the meniscus, including the meniscal roots, by fully automatic three-dimensional MRI analysis

2022 ◽  
pp. 100007
Author(s):  
Hisako Katano ◽  
Nobutake Ozeki ◽  
Hideyuki Koga ◽  
Kenji Suzuki ◽  
Jun Masumoto ◽  
...  
Keyword(s):  
Measurement Error ◽  
Three Dimensional ◽  
Fully Automatic

scholarly journals Relationship between medial meniscus extrusion and cartilage measurements in the knee by fully automatic three-dimensional MRI analysis

2020 ◽  
Author(s):  
Hayato Aoki ◽  
Nobutake Ozeki ◽  
Hisako Katano ◽  
Akinobu Hyodo ◽  
Yugo Miura ◽  
...  
Keyword(s):  
Medial Meniscus ◽  
Three Dimensional ◽  
Cartilage Thickness ◽  
Similarity Coefficients ◽  
Tibial Cartilage ◽  
Fully Automatic ◽  
The Relationship ◽  
Medial Meniscus Extrusion ◽  
Meniscus Extrusion ◽  
And Cartilage

Abstract BackgroundWe developed a fully automatic three-dimensional knee MRI analysis software that can quantify meniscus extrusion and cartilage measurements, including the projected cartilage area ratio (PCAR), which represents the ratio of the subject’s actual cartilage area to their ideal cartilage area. We also collected 3D MRI knee data from 561 volunteers (aged 30–79 years) from the “Kanagawa Knee Study.” Our purposes were to verify the accuracy of the software for automatic cartilage and meniscus segmentation using knee MRI and to examine the relationship between medial meniscus extrusion measurements and cartilage measurements from Kanagawa Knee Study data.MethodsWe constructed a neural network for the software by randomly choosing 10 healthy volunteers and 103 patients with knee pain. We validated the algorithm by randomly selecting 108 of these 113 subjects for training, and determined Dice similarity coefficients from five other subjects. We constructed a neural network using all data (113 subjects) for training. Cartilage thickness, cartilage volume, and PCAR in the medial femoral, lateral femoral, medial tibial, and lateral tibial regions were quantified by using the trained software on Kanagawa Knee Study data and their relationship with subject height was investigated. We also quantified the medial meniscus coverage ratio (MMCR), defined as the ratio of the overlapping area between the medial meniscus area and the medial tibial cartilage area to the medial tibial cartilage area. Finally, we examined the relationship between MMCR and PCAR at middle central medial tibial (mcMT) subregion located in the center of nine subregions in the medial tibial cartilage.ResultsDice similarity coefficients for cartilage and meniscus were both approximately 0.9. The femoral and tibial cartilage thickness and volume at each region correlated with height, but PCAR did not correlate with height in most settings. PCAR at the mcMT was significantly correlated with MMCR.ConclusionsOur software showed high segmentation accuracy for the knee cartilage and meniscus. PCAR was more useful than cartilage thickness or volume since it was less affected by height. A relationship was observed between the medial tibial cartilage measurements and the medial meniscus extrusion measurement in our cross-sectional study.Trial registration: UMIN, UMIN000032826; 1 September 2018,https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000037299

scholarly journals Fully automatic three-dimensional MRI analysis for the cartilage and meniscus of the knee: Kanagawa Knee Study

2020 ◽  
Author(s):  
Hayato Aoki ◽  
Nobutake Ozeki ◽  
Hisako Katano ◽  
Akinobu Hyodo ◽  
Yugo Miura ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Cross Sectional Study ◽  
Cartilage Volume ◽  
Cartilage Thickness ◽  
Sectional Study ◽  
Similarity Coefficients ◽  
Cross Sectional ◽  
Coverage Ratio ◽  
Segmentation Accuracy ◽  
Fully Automatic

Abstract ObjectiveWe have developed a fully automatic three-dimensional MRI analysis software that measures the projected cartilage area ratio (PCAR) to allow for the quantification of the cartilage in the knee. Our objectives were to verify our software’s accuracy for segmentation of cartilage and meniscus and to quantify cartilage and meniscus extrusion in our cross-sectional study. We also examined which cartilage quantification was most affected by age and analyzed the relationship between PCAR and meniscus extrusion.MethodsMRI data from 108 subjects were selected for training, and Dice similarity coefficients were determined from 5 other subjects to verify the accuracy. Our cross-sectional study included other 561 subjects between 30–70 years of age. We quantified cartilage thickness, cartilage volume, and PCAR (0.0–1.5 mm) in medial femoral, lateral femoral, medial tibial, and medial lateral regions. Each region was divided into nine subregions, with particular focus on the medial central (mc) subregion. The medial meniscus coverage ratio (MMCR) was investigated as a quantification for meniscus extrusion.ResultsDice similarity coefficients for cartilage and meniscus were both approximately 0.9. Among cartilage quantifications, the highest absolute value of the correlation coefficient with age was mcMT PCAR 1.0 mm in females and mcMT cartilage thickness in males. In females, mcMT PCAR 1.0 mm was correlated with MMCR, although MMCR was not correlated with age. In males, mcMT PCAR 0.0 mm was correlated with MMCR.ConclusionsOur software showed high segmentation accuracy and provided numerous quantifications of cartilage related to age and meniscus extrusion.Trial registration: UMIN, UMIN000032826. Registered 1 September 2018, https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000037299

Left coronary artery thrombus characterized by a fully automatic three-dimensional gated reconstruction

2009 ◽  
Vol 74 (1) ◽  
pp. 97-100 ◽  
Author(s):  
Gert A.F. Schoonenberg ◽  
Joel A. Garcia ◽  
John D. Carroll
Keyword(s):  
Coronary Artery ◽  
Left Coronary Artery ◽  
Three Dimensional ◽  
Fully Automatic

End-Wall Film Cooling Through Fan-Shaped Holes With Different Area Ratios

2006 ◽  
Vol 129 (2) ◽  
pp. 212-220 ◽  
Author(s):  
Giovanna Barigozzi ◽  
Giuseppe Franchini ◽  
Antonio Perdichizzi
Keyword(s):  
Secondary Flow ◽  
Mass Flow ◽  
Film Cooling ◽  
Three Dimensional ◽  
Wide Band ◽  
Lateral Spreading ◽  
Area Ratio ◽  
Adiabatic Effectiveness ◽  
Flow Effects ◽  
End Wall

The present paper reports on the aerothermal performance of a nozzle vane cascade, with film-cooled end walls. The coolant is injected through four rows of cylindrical holes with conical expanded exits. Two end-wall geometries with different area ratios have been compared. Tests have been carried out at low speed (M=0.2), with coolant to mainstream mass flow ratio varied in the range 0.5–2.5%. Secondary flow assessment has been performed through three-dimensional (3D) aerodynamic measurements, by means of a miniaturized five-hole probe. Adiabatic effectiveness distributions have been determined by using the wide-band thermochromic liquid crystals technique. For both configurations and for all the blowing conditions, the coolant share among the four rows has been determined. The aerothermal performances of the cooled vane have been analyzed on the basis of secondary flow effects and laterally averaged effectiveness distributions; this analysis was carried out for different coolant mass flow ratios. It was found that the smaller area ratio provides better results in terms of 3D losses and secondary flow effects; the reason is that the higher momentum of the coolant flow is going to better reduce the secondary flow development. The increase of the fan-shaped hole area ratio gives rise to a better coolant lateral spreading, but appreciable improvements of the adiabatic effectiveness were detected only in some regions and for large injection rates.

Oxygen electrode design criteria and performance characteristics: recessed cathode

1978 ◽  
Vol 45 (1) ◽  
pp. 145-154 ◽  
Author(s):  
G. Schneiderman ◽  
T. K. Goldstick
Keyword(s):  
Measurement Error ◽  
Performance Optimization ◽  
Surrounding Medium ◽  
Three Dimensional ◽  
Concentration Field ◽  
Oxygen Electrode ◽  
Current Sensitivity ◽  
Steady State Operation ◽  
Oxygen Electrodes ◽  
And Performance

A computer simulation of the steady-state operation of recessed (Whalen-type) polarographic oxygen electrodes has been developed to give the design factors important for performance optimization. The simulation makes use of a specially formulated three-dimensional orthogonal coordinate system with the geometry identical to the actual recessed cathode and gives the oxygen concentration field induced by it in the surrounding medium. Equations are presented which allow one to calculate, for any recessed cathode, the current sensitivity, maximum stirring artifact, measurement error, and time constant. Comparisons with analytically obtained expressions for the corresponding quantities for idealized, spherosymmetric cathodes demonstrate the unique aspects of recessed-cathode performance. For commonly used electrodes, a recess length-to-cathode diameter ratio of greater than 10 is found to give a negligible stirring artifact, a negligible measurement error, and a rapid response.

scholarly journals Ultrasound validity in the measurement of knee cartilage thickness

2008 ◽  
Vol 68 (8) ◽  
pp. 1322-1327 ◽  
Author(s):  
E Naredo ◽  
C Acebes ◽  
I Moller ◽  
F Canillas ◽  
J J de Agustin ◽  
...  
Keyword(s):  
Cartilage Thickness ◽  
Knee Cartilage

Creation of Patterned Gold Nanostructures via Electron-Beam-Induced Deposition

2013 ◽  
Vol 1546 ◽  
Author(s):  
Anastasia V. Riazanova ◽  
Johannes J. L. Mulders ◽  
Lyubov M. Belova
Keyword(s):  
Electron Beam ◽  
Three Dimensional ◽  
Area Ratio ◽  
Ex Situ ◽  
Geometrical Shape ◽  
Local Electron ◽  
Post Annealing ◽  
Treatment Conditions ◽  
Heat Treated ◽  
Electron Beam Induced Deposition

ABSTRACTOne of the methods to grow nanoscale three-dimensional (3D) Au patterns is to perform local electron-beam-induced deposition (EBID) using the Me2Au(acac) precursor inside the chamber of a scanning electron microscope (SEM). However, due to the organometallic nature of the chemical, the concentration of the metallic constituent in the as-deposited structure is dramatically low, at around 10 at. % of Au. Ex-situ post-annealing of Me2Au(acac) EBIDs is a very promising purification approach, resulting in an Au content of > 92 at. % after annealing at 600 °C. However, in most of the cases it also distorts the geometrical shape of the heat-treated structure, preserving of which is essential for the application. In this paper we present a systematic study of the dependence between the annealing parameters and resulting purity in combination with the shape of the Au structure. Optimized heat treatment conditions for the creation of well-purified high aspect ratio Au pillar array are presented; and for planar continuous structures, the importance of the parameter height to area ratio is identified.

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