Jane Haslam - Profile on Academia.edu (original) (raw)
Papers by Jane Haslam
Selecting a feature in a camera image to be added to a model image
Procede et systeme de caracterisation de la morphologie d'une articulation du genou
La presente invention concerne un procede et un systeme de caracterisation d'une articulation... more La presente invention concerne un procede et un systeme de caracterisation d'une articulation en termes de morphologie squelettique. Une pluralite de sites associes au modele d'une structure squelettique d'articulation du genou sont fixes et utilises pour parametrer des positions de cette pluralite de sites chez un sujet donne et, pour calculer ainsi des parametres d'un modele statistique deformable. La morphologie squelettique est ensuite caracterisee a partir des parametres calcules de ce modele statistique deformable.
Method and apparatus for generating model data from camera images
Procédés et système de détection et de suivi de l'ostéoporose
L'invention concerne un procede et un systeme de detection et de suivi de l'osteoporose. ... more L'invention concerne un procede et un systeme de detection et de suivi de l'osteoporose. Le procede selon l'invention permet de caracteriser une image d'une vertebre cible en construisant un modele informatique a partir d'un ensemble d'echantillons d'images de variations pathologiques et non pathologiques des vertebres representant des variations dans la forme des vertebres. Ledit procede consiste egalement a recevoir une image d'une vertebre cible d'un sujet, et a automatiquement estimer le contour des limites laterales des plaques corticales inferieures sur l'image. On varie les parametres du modele afin de determiner un ensemble representant une forme modele qui se rapproche du contour estime des limites des plaques corticales. Le procede consiste a automatiquement caracteriser la vertebre cible sur la base de l'ensemble de parametres de modele qui ont ete determines, et a sortir sur un dispositif d'affichage la caracterisation de l...
Computer Program Products and Methods for Detection and Tracking of Rheumatoid Arthritis
Methods of and System for Detection and Tracking of Osteoporosis
Method and system for characterization of knee joint morphology
Method and system for cleaning motion capture data
Medical image segmentation using active shape models
Performance of statistical models of shape and appearance for semi-automatic segmentations of spinal vertebrae T4 to L4 on digitised VFA images
The Spine Journal, 2015
Despite its clinical importance, accurate identification of vertebral fractures is problematic an... more Despite its clinical importance, accurate identification of vertebral fractures is problematic and time-consuming. There is a recognized need to improve the detection of vertebral fractures so that appropriate high-risk patients can be selected to initiate clinically beneficial therapeutic interventions. To develop and evaluate semiautomatic algorithms for detailed annotation of vertebral bodies from T4 to L4 in digitized lateral spinal dual-energy X-ray absorptiometry (DXA) vertebral fracture assessment (VFA) images. Using lateral spinal DXA VFA images from subjects imaged at University Hospital fracture liaison service, image algorithms were developed for semiautomatic detailed annotation of vertebral bodies from T4 to L4. Two hundred one women aged 50 years or older with nonvertebral fractures. Algorithm accuracy and precision. Statistical models of vertebral shape and appearance from T4 to L4 were constructed using VFA images from 130 subjects. The resulting models form a part of an algorithm for performing semiautomatic detailed annotation of vertebral bodies from T4 to L4. Algorithm accuracy and precision were evaluated on a test-set of 71 independent images. Overall accuracy was 0.72 mm (3.00% of vertebral height) and overall precision was 0.26 mm (1.11%) for point-to-line distance. Accuracy and precision were best on normal vertebrae (0.65 mm [2.67%] and 0.21 mm [0.90%], respectively) and mild fractures (0.78 mm [3.18%] and 0.32 mm [1.39%], respectively), but accuracy and precision errors were higher for moderate (1.07 mm [4.66%] and 0.48 mm [2.15%], respectively) and severe fractures (2.07 mm [9.65%] and 1.10 mm [5.09%], respectively). Accuracy and precision results for the algorithm were comparable with other reported results in the literature. This semiautomatic image analysis had high overall accuracy and precision on normal vertebrae and mild fractures, but performed less well in moderate and severe fractures. It is, therefore, a useful tool to identify normality of vertebral shape and to identify mild fractures.
Procedings of the British Machine Vision Conference 1994, 1994
Methods for automatic image interpretation based on the use of deformable template models have pr... more Methods for automatic image interpretation based on the use of deformable template models have proved very successful. Whatever deformable template scheme is used, one of the basic requirements is a method for assessing the likelihood that a particular model instance is the correct interpretation of a given image. We describe a Bayesian 'fitness' measure which combines the likelihood of the model shape with the evidential support in a principled way. Image search is carried out by minimising the fitness measure using multi-scale quasi-Newtonian optimisation. We have previously compared the performance of different fitness measures. Here we give results for the new method and show that, by making optimal use of the image evidence, it achieves more accurate interpretation than the best of the methods we have previously tested.
A Cluster Analysis Approach for the Characterization of Dynamic PET Data
Quantification of Brain Function Using PET, 1996
Bone, 2014
We describe the methods and reliability of radiographic vertebral fracture assessment in MrOS, a ... more We describe the methods and reliability of radiographic vertebral fracture assessment in MrOS, a cohort of community dwelling men aged ≥65 yrs. Lateral spine radiographs were obtained at Visit 1 (2000-2) and 4.6 years later (Visit 2). Using a workflow tool (SpineAnalyzer™, Optasia Medical), a physician reader completed semi-quantitative (SQ) scoring. Prior to SQ scoring, technicians performed "triage" to reduce physician reader workload, whereby clearly normal spine images were eliminated from SQ scoring with all levels assumed to be SQ = 0 (no fracture, "triage negative"); spine images with any possible fracture or abnormality were passed to the physician reader as "triage positive" images. Using a quality assurance sample of images (n = 20 participants; 8 with baseline only and 12 with baseline and follow-up images) read multiple times, we calculated intra-reader kappa statistics and percent agreement for SQ scores. A subset of 494 participants' images was read regardless of triage classification to calculate the specificity and sensitivity of triage. Technically adequate images were available for 5958 of 5994 participants at Visit 1, and 4399 of 4423 participants at Visit 2. Triage identified 3215 (53.9%) participants with radiographs that required further evaluation by the physician reader. For prevalent fractures at Visit 1 (SQ ≥ 1), intra-reader kappa statistics ranged from 0.79 to 0.92; percent agreement ranged from 96.9% to 98.9%; sensitivity of the triage was 96.8% and specificity of triage was 46.3%. In conclusion, SQ scoring had excellent intra-rater reliability in our study. The triage process reduces expert reader workload without hindering the ability to identify vertebral fractures.
Comprehensive Vertebral Deformity and Vertebral Fracture Assessment in Clinical Practice
Spine, 2013
Study design randomized intra- and inter-reader reproducibility study. To evaluate reproducibilit... more Study design randomized intra- and inter-reader reproducibility study. To evaluate reproducibility of quantitative morphometry (QM) and agreement of dichotomous fracture/no-fracture status on lateral spinal radiographs acquired during routine clinical practice using a clinical workflow tool. Several recent guidelines have underlined the importance of Genant semi-quantitative scoring and selective QM to confirm and grade suspected vertebral fractures in clinical practice. Thoracic and lumbar spine radiographs were acquired from 98 consecutive subjects (mean age, 60.1 ± 11.7 yr) attending the clinic for osteoporosis evaluation. For each subject, QM and Genant semi-quantitative scoring were performed on all evaluable vertebrae from L4 to T4 using a software workflow tool. A radiologist and an experienced radiographical technician performed 2 repeat reading sessions of the radiographs 12 months apart, blinded to each other's results; for the second read, the cases were anonymized and the order was randomized. Inter-reader reproducibility results were 3.1% and 3.2% coefficient of variation (%) for heights, 0.030 and 0.031 root mean square standard deviation for height ratios. For intrareader reproducibility, these values were 2.2% and 3.5% coefficient of variation %; 0.023 and 0.034 root mean square standard deviation. Kappa score results for agreement of dichotomous fracture/no-fracture status were 0.67 and 0.72 (inter-rater) and 0.50 and 0.67 (intrarater). The software assessed in this study is a reliable clinical tool that facilitates QM and Genant semi-quantitative scoring of the spine in routine clinical practice. 3.
Adaptive correction for scatter and attenuation in fully three-dimensional PET
Nuclear Medicine Communications, 1995
Image and Vision Computing, 1994
This paper describes a technique for building compact models of the shape and appearance of flexi... more This paper describes a technique for building compact models of the shape and appearance of flexible objects (such as organs) seen in 2D images. The models are derived from the statistics of labelled imqes cont~l~nin~ examples of the objects. Etch model consists of a flexible shape template. describing how the relevant locations of important points on the objects can vary. and >I statistical model of the expected &rey levels in :I region artrund each model point. We describe how the models c;m hc used in local image search. and give examples of their applktion to medical im;lges.
A new tool for quantitative assessment of vertebral morphometry measured by DXA: Inter-observer reproducibility and comparison to standard method
Bone, 2010
Response to BONE-D-14-00884
Bone, 2014
Selecting a feature in a camera image to be added to a model image
Procede et systeme de caracterisation de la morphologie d'une articulation du genou
La presente invention concerne un procede et un systeme de caracterisation d'une articulation... more La presente invention concerne un procede et un systeme de caracterisation d'une articulation en termes de morphologie squelettique. Une pluralite de sites associes au modele d'une structure squelettique d'articulation du genou sont fixes et utilises pour parametrer des positions de cette pluralite de sites chez un sujet donne et, pour calculer ainsi des parametres d'un modele statistique deformable. La morphologie squelettique est ensuite caracterisee a partir des parametres calcules de ce modele statistique deformable.
Method and apparatus for generating model data from camera images
Procédés et système de détection et de suivi de l'ostéoporose
L'invention concerne un procede et un systeme de detection et de suivi de l'osteoporose. ... more L'invention concerne un procede et un systeme de detection et de suivi de l'osteoporose. Le procede selon l'invention permet de caracteriser une image d'une vertebre cible en construisant un modele informatique a partir d'un ensemble d'echantillons d'images de variations pathologiques et non pathologiques des vertebres representant des variations dans la forme des vertebres. Ledit procede consiste egalement a recevoir une image d'une vertebre cible d'un sujet, et a automatiquement estimer le contour des limites laterales des plaques corticales inferieures sur l'image. On varie les parametres du modele afin de determiner un ensemble representant une forme modele qui se rapproche du contour estime des limites des plaques corticales. Le procede consiste a automatiquement caracteriser la vertebre cible sur la base de l'ensemble de parametres de modele qui ont ete determines, et a sortir sur un dispositif d'affichage la caracterisation de l...
Computer Program Products and Methods for Detection and Tracking of Rheumatoid Arthritis
Methods of and System for Detection and Tracking of Osteoporosis
Method and system for characterization of knee joint morphology
Method and system for cleaning motion capture data
Medical image segmentation using active shape models
Performance of statistical models of shape and appearance for semi-automatic segmentations of spinal vertebrae T4 to L4 on digitised VFA images
The Spine Journal, 2015
Despite its clinical importance, accurate identification of vertebral fractures is problematic an... more Despite its clinical importance, accurate identification of vertebral fractures is problematic and time-consuming. There is a recognized need to improve the detection of vertebral fractures so that appropriate high-risk patients can be selected to initiate clinically beneficial therapeutic interventions. To develop and evaluate semiautomatic algorithms for detailed annotation of vertebral bodies from T4 to L4 in digitized lateral spinal dual-energy X-ray absorptiometry (DXA) vertebral fracture assessment (VFA) images. Using lateral spinal DXA VFA images from subjects imaged at University Hospital fracture liaison service, image algorithms were developed for semiautomatic detailed annotation of vertebral bodies from T4 to L4. Two hundred one women aged 50 years or older with nonvertebral fractures. Algorithm accuracy and precision. Statistical models of vertebral shape and appearance from T4 to L4 were constructed using VFA images from 130 subjects. The resulting models form a part of an algorithm for performing semiautomatic detailed annotation of vertebral bodies from T4 to L4. Algorithm accuracy and precision were evaluated on a test-set of 71 independent images. Overall accuracy was 0.72 mm (3.00% of vertebral height) and overall precision was 0.26 mm (1.11%) for point-to-line distance. Accuracy and precision were best on normal vertebrae (0.65 mm [2.67%] and 0.21 mm [0.90%], respectively) and mild fractures (0.78 mm [3.18%] and 0.32 mm [1.39%], respectively), but accuracy and precision errors were higher for moderate (1.07 mm [4.66%] and 0.48 mm [2.15%], respectively) and severe fractures (2.07 mm [9.65%] and 1.10 mm [5.09%], respectively). Accuracy and precision results for the algorithm were comparable with other reported results in the literature. This semiautomatic image analysis had high overall accuracy and precision on normal vertebrae and mild fractures, but performed less well in moderate and severe fractures. It is, therefore, a useful tool to identify normality of vertebral shape and to identify mild fractures.
Procedings of the British Machine Vision Conference 1994, 1994
Methods for automatic image interpretation based on the use of deformable template models have pr... more Methods for automatic image interpretation based on the use of deformable template models have proved very successful. Whatever deformable template scheme is used, one of the basic requirements is a method for assessing the likelihood that a particular model instance is the correct interpretation of a given image. We describe a Bayesian 'fitness' measure which combines the likelihood of the model shape with the evidential support in a principled way. Image search is carried out by minimising the fitness measure using multi-scale quasi-Newtonian optimisation. We have previously compared the performance of different fitness measures. Here we give results for the new method and show that, by making optimal use of the image evidence, it achieves more accurate interpretation than the best of the methods we have previously tested.
A Cluster Analysis Approach for the Characterization of Dynamic PET Data
Quantification of Brain Function Using PET, 1996
Bone, 2014
We describe the methods and reliability of radiographic vertebral fracture assessment in MrOS, a ... more We describe the methods and reliability of radiographic vertebral fracture assessment in MrOS, a cohort of community dwelling men aged ≥65 yrs. Lateral spine radiographs were obtained at Visit 1 (2000-2) and 4.6 years later (Visit 2). Using a workflow tool (SpineAnalyzer™, Optasia Medical), a physician reader completed semi-quantitative (SQ) scoring. Prior to SQ scoring, technicians performed "triage" to reduce physician reader workload, whereby clearly normal spine images were eliminated from SQ scoring with all levels assumed to be SQ = 0 (no fracture, "triage negative"); spine images with any possible fracture or abnormality were passed to the physician reader as "triage positive" images. Using a quality assurance sample of images (n = 20 participants; 8 with baseline only and 12 with baseline and follow-up images) read multiple times, we calculated intra-reader kappa statistics and percent agreement for SQ scores. A subset of 494 participants' images was read regardless of triage classification to calculate the specificity and sensitivity of triage. Technically adequate images were available for 5958 of 5994 participants at Visit 1, and 4399 of 4423 participants at Visit 2. Triage identified 3215 (53.9%) participants with radiographs that required further evaluation by the physician reader. For prevalent fractures at Visit 1 (SQ ≥ 1), intra-reader kappa statistics ranged from 0.79 to 0.92; percent agreement ranged from 96.9% to 98.9%; sensitivity of the triage was 96.8% and specificity of triage was 46.3%. In conclusion, SQ scoring had excellent intra-rater reliability in our study. The triage process reduces expert reader workload without hindering the ability to identify vertebral fractures.
Comprehensive Vertebral Deformity and Vertebral Fracture Assessment in Clinical Practice
Spine, 2013
Study design randomized intra- and inter-reader reproducibility study. To evaluate reproducibilit... more Study design randomized intra- and inter-reader reproducibility study. To evaluate reproducibility of quantitative morphometry (QM) and agreement of dichotomous fracture/no-fracture status on lateral spinal radiographs acquired during routine clinical practice using a clinical workflow tool. Several recent guidelines have underlined the importance of Genant semi-quantitative scoring and selective QM to confirm and grade suspected vertebral fractures in clinical practice. Thoracic and lumbar spine radiographs were acquired from 98 consecutive subjects (mean age, 60.1 ± 11.7 yr) attending the clinic for osteoporosis evaluation. For each subject, QM and Genant semi-quantitative scoring were performed on all evaluable vertebrae from L4 to T4 using a software workflow tool. A radiologist and an experienced radiographical technician performed 2 repeat reading sessions of the radiographs 12 months apart, blinded to each other's results; for the second read, the cases were anonymized and the order was randomized. Inter-reader reproducibility results were 3.1% and 3.2% coefficient of variation (%) for heights, 0.030 and 0.031 root mean square standard deviation for height ratios. For intrareader reproducibility, these values were 2.2% and 3.5% coefficient of variation %; 0.023 and 0.034 root mean square standard deviation. Kappa score results for agreement of dichotomous fracture/no-fracture status were 0.67 and 0.72 (inter-rater) and 0.50 and 0.67 (intrarater). The software assessed in this study is a reliable clinical tool that facilitates QM and Genant semi-quantitative scoring of the spine in routine clinical practice. 3.
Adaptive correction for scatter and attenuation in fully three-dimensional PET
Nuclear Medicine Communications, 1995
Image and Vision Computing, 1994
This paper describes a technique for building compact models of the shape and appearance of flexi... more This paper describes a technique for building compact models of the shape and appearance of flexible objects (such as organs) seen in 2D images. The models are derived from the statistics of labelled imqes cont~l~nin~ examples of the objects. Etch model consists of a flexible shape template. describing how the relevant locations of important points on the objects can vary. and >I statistical model of the expected &rey levels in :I region artrund each model point. We describe how the models c;m hc used in local image search. and give examples of their applktion to medical im;lges.
A new tool for quantitative assessment of vertebral morphometry measured by DXA: Inter-observer reproducibility and comparison to standard method
Bone, 2010
Response to BONE-D-14-00884
Bone, 2014