Study of carpal bone morphology and position in three dimensions by image analysis from computed tomography scans of the wrist

The objective of this study is to quantitatively evaluate the soil structure behavior when under shear stress to understand the mechanism of shear zone formation using a micro-focus X-ray computed tomography (CT) scanner to visualize the internal samples without causing disturbance. A new image-analysis method was proposed to systematically evaluate the particle length and direction by fitting the particle as an ellipsoid. Subsequently, a direct shear experiment was conducted on soil materials, and shear band was scanned using a micro-focus X-ray CT scanner. After validating the proposed method, the soil structure was evaluated in the shear zone via image analysis on the CT images. Furthermore, the strain inside the specimen was evaluated using digital image correlation. The results showed that a partial change in the particle direction occurred when the volume expansion inside the shear zone exceeded the peak. In addition, the width of the shear zone was ~7.1 times the median grain size of the sand used; however, the region exhibiting a change in the direction of the particles was narrow and confined to the vicinity of the shear plane.

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In vivo measurements of muscle volume by automatic image analysis of spiral computed tomography scans

Animal Science ◽

10.1079/asc200662 ◽

2006 ◽

Vol 82 (4) ◽

pp. 545-553 ◽

Cited By ~ 23

Author(s):

E. A. Navajas ◽

C. A. Glasbey ◽

K. A. McLean ◽

A. V. Fisher ◽

A. J. L. Charteris ◽

...

Keyword(s):

Computed Tomography ◽

Image Analysis ◽

Muscle Volume ◽

Spiral Computed Tomography ◽

Lumbar Region ◽

Automatic Image Analysis ◽

Analysis Method ◽

Image Analysis Method ◽

Spiral Computed ◽

Computed Tomography Scans

AbstractThis study investigates the accuracy of an automatic image analysis method that was developed for spiral computed tomography scans (SCTS), with the objective of calculating the volume of muscle in the hind leg (HLMVCT) and lumbar region (LRMVCT) in lambs. The first step in the image analysis method was the isolation (segmentation) of the muscle regions in each image of the SCTS, using a new program that was implemented in the Sheep Tomogram Analysis Routines software (STAR). Due to the differences of muscle shape in the regions investigated, the new segmentation program applies different segmentation paths in specific subregions. These were automatically identified by the program based on skeletal landmarks. After the segmentation was completed, the muscles areas were automatically measured by counting the pixels representing muscle in each image; the volumes were calculated by adding the muscle areas of each image multiplied by the depth of the image (inter-slice distance). The accuracy of these measures of muscle volume was evaluated, using regression analysis, by comparing HLMVCT and LRMVCT to the hind leg and lumbar region muscle weights measured after dissection (HLMWD, no. =240, and LRMWD, no. =50, respectively) of Texel (TEX) and Scottish Blackface (SBF) female and male lambs slaughtered in 2003-04. The effects of breed, sex and year on the association (SCTS v. dissection) were evaluated. There was a strong association between HLMVCT and HLMWD ( R2=97·4%), which only increased slightly ( R2=97·7%) when breed was included in the model. This indicates that HLMWD can be estimated directly from HLMVCT with a high degree of accuracy. For the lumbar region, the association was high ( R2=83·0% to 88·8% depending on the model) but lower than in the hind leg, probably because the automatic segmentation isolates only the areas of the longissimus lumborum and multifidi muscles. Breed had a significant effect on the prediction of LRMWD from LRMVCT, as well as sex in the case of the TEX lambs. The results indicated that the predictions of LRMWD from LRMVCT require different equations for very divergent breeds such as TEX and SBF.

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Faculty Opinions recommendation of Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718023711.793479508 ◽

2013 ◽

Author(s):

Michael Brodsky ◽

Paula Grigorian

Keyword(s):

Computed Tomography ◽

Cancer Risk ◽

Data Linkage ◽

Linkage Study ◽

Computed Tomography Scans

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Deep Learning based Staging of Bone Lesions from Computed Tomography Scans (January 2021)

IEEE Access ◽

10.1109/access.2021.3074051 ◽

2021 ◽

pp. 1-1

Author(s):

Samira Masoudi ◽

Sherif Mehralivand ◽

Stephanie A. Harmon ◽

Nathan Lay ◽

Liza Lindenberg ◽

...

Keyword(s):

Computed Tomography ◽

Deep Learning ◽

Bone Lesions ◽

Computed Tomography Scans

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Utility of Head Computed Tomography Scans Prior to Outpatient Follow-up for Low-Risk Mild Traumatic Brain Injury

World Neurosurgery ◽

10.1016/j.wneu.2021.04.087 ◽

2021 ◽

Author(s):

Matthew W. Weber ◽

Jeffrey Z. Nie ◽

Victoria L. Watson ◽

Nathan J. Nordmann ◽

Joseph Bernard ◽

...

Keyword(s):

Computed Tomography ◽

Traumatic Brain Injury ◽

Brain Injury ◽

Mild Traumatic Brain Injury ◽

Low Risk ◽

Computed Tomography Scans ◽

Head Computed Tomography

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Correlation between tympanometry volume and three-dimensional computed tomography mastoid volumetry in tympanoplasty candidates

The Journal of Laryngology & Otology ◽

10.1017/s002221512100164x ◽

2021 ◽

pp. 1-5

Author(s):

L Epprecht ◽

L Qingsong ◽

N Stenz ◽

S Hashimi ◽

T Linder

Keyword(s):

Computed Tomography ◽

Tympanic Membrane ◽

Cell Volume ◽

Radiation Injury ◽

Three Dimensional ◽

Non Invasive ◽

Tympanic Membrane Perforations ◽

Computed Tomography Scans ◽

Air Cells ◽

Mastoid Air Cells

Abstract Objective Ventilation of the middle ear and mastoid air cells is believed to play an important role in the pathogenesis of chronic ear disease. Traditionally, ventilation is assessed by computed tomography. However, this exposes patients to cumulative radiation injury. In cases with a perforation in the tympanic membrane, tympanometry potentially presents a non-invasive alternative to measure the ventilated middle-ear and mastoid air cell volume. This study hypothesised that total tympanometry volume correlates with ventilated middle-ear and mastoid air cell volume. Method Total tympanometry volume was compared with ventilated middle-ear and mastoid air cell volume on computed tomography scans in 20 tympanic membrane perforations. Results There was a high correlation between tympanometry and computed tomography volumes (r = 0.78; p < 0.001). A tympanometry volume more than 2 ml predicted good ventilation on computed tomography. Conclusion These results may help reduce the need for pre-operative computed tomography in uncomplicated cases with tympanic membrane perforations.

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