B Godbout

Publications (10)7.23 Total impact

• Conference Proceeding: Coupling 2D/3D registration method and statistical model to perform 3D reconstruction from partial x-rays images data

  T. Cresson, R. Chav, D. Branchaud, L. Humbert, B. Godbout, B. Aubert, W. Skalli, J.A. De Guise
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  ABSTRACT: 3D reconstructions of the spine from a frontal and sagittal radiographs is extremely challenging. The overlying features of soft tissues and air cavities interfere with image processing. It is also difficult to obtain information that is accurate enough to reconstruct complete 3D models. To overcome these problems, the proposed method efficiently combines the partial information contained in two images from a patient with a statistical 3D spine model generated from a database of scoliotic patients. The algorithm operates through two simultaneous iterating processes. The first one generates a personalized vertebra model using a 2D/3D registration process with bone boundaries extracted from radiographs, while the other one infers the position and the shape of other vertebrae from the current estimation of the registration process using a statistical 3D model. Experimental evaluations have shown good performances of the proposed approach in terms of accuracy and robustness when compared to CT-scan.
  Engineering in Medicine and Biology Society, 2009. EMBC 2009. Annual International Conference of the IEEE; 10/2009
• Article: Fast 3D reconstruction of the spine from biplanar radiography: a diagnosis tool for routine scoliosis diagnosis and research in biomechanics

  L. Humbert, J.A. De Guise, B. Godbout, T. Cresson, B. Aubert, D. Branchaud, R. Chav, P. Gravel, S. Parent, J. Dubousset, W. Skalli
  Computer Methods in Biomechanics and Biomedical Engineering 08/2009; 12(S1):151-152. · 0.85 Impact Factor
• Source

  Available from: Ludovic Humbert

  Article: 3D reconstruction of the spine from biplanar X-rays using parametric models based on transversal and longitudinal inferences.

  L Humbert, J A De Guise, B Aubert, B Godbout, W Skalli
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  ABSTRACT: Reconstruction methods from biplanar X-rays provide 3D analysis of spinal deformities for patients in standing position with a low radiation dose. However, such methods require an important reconstruction time and there is a clinical need for fast and accurate techniques. This study proposes and evaluates a novel reconstruction method of the spine from biplanar X-rays. The approach uses parametric models based on longitudinal and transversal inferences. A first reconstruction level, dedicated to routine clinical use, allows to get a fast estimate (reconstruction time: 2 min 30 s) of the 3D reconstruction and accurate clinical measurements. The clinical measurements precision (evaluated on asymptomatic subjects, moderate and severe scolioses) was between 1.2 degrees and 5.6 degrees. For a more accurate 3D reconstruction (complex pathologies or research purposes), a second reconstruction level can be obtained within a reduced reconstruction time (10 min) with a fine adjustment of the 3D models. The mean shape accuracy in comparison with CT-scan was 1.0 mm. The 3D reconstruction method precision was 1.8mm for the vertebrae position and between 2.3 degrees and 3.9 degrees for the orientation. With a reduced reconstruction time, an improved accuracy and precision and a method proposing two reconstruction levels, this approach is efficient for both clinical routine uses and research purposes.
  Medical Engineering & Physics 03/2009; 31(6):681-7. · 1.62 Impact Factor
• Article: Coupling 2D/3D registration method and statistical model to perform 3D reconstruction from partial x-rays images data.

  T Cresson, R Chav, D Branchaud, L Humbert, B Godbout, B Aubert, W Skalli, J A De Guise
  [show abstract] [hide abstract]
  ABSTRACT: 3D reconstructions of the spine from a frontal and sagittal radiographs is extremely challenging. The overlying features of soft tissues and air cavities interfere with image processing. It is also difficult to obtain information that is accurate enough to reconstruct complete 3D models. To overcome these problems, the proposed method efficiently combines the partial information contained in two images from a patient with a statistical 3D spine model generated from a database of scoliotic patients. The algorithm operates through two simultaneous iterating processes. The first one generates a personalized vertebra model using a 2D/3D registration process with bone boundaries extracted from radiographs, while the other one infers the position and the shape of other vertebrae from the current estimation of the registration process using a statistical 3D model. Experimental evaluations have shown good performances of the proposed approach in terms of accuracy and robustness when compared to CT-scan.
  Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 01/2009; 2009:1008-11.
• Conference Proceeding: Surface reconstruction from planar x-ray images using moving least squares

  T. Cresson, B. Godbout, D. Branchaud, R. Chav, P. Gravel, J.A. De Guise
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  ABSTRACT: Planar radiographs still are the gold standard for the measurement of the skeletal weight-bearing shape and posture. In this paper, we propose to use an as-rigid-as-possible deformation approach based on moving least squares to obtain 3D personalized bone models from planar x-ray images. Our prototype implementation is capable of performing interactive rate shape editing. The biplane reconstructions of both femur and vertebrae show a good accuracy when compared to CT-scan.
  Engineering in Medicine and Biology Society, 2008. EMBS 2008. 30th Annual International Conference of the IEEE; 09/2008
• Article: Surface reconstruction from planar x-ray images using moving least squares.

  T Cresson, B Godbout, D Branchaud, R Chav, P Gravel, J A De Guise
  [show abstract] [hide abstract]
  ABSTRACT: Planar radiographs still are the gold standard for the measurement of the skeletal weight-bearing shape and posture. In this paper, we propose to use an as-rigid-as-possible deformation approach based on moving least squares to obtain 3D personalized bone models from planar x-ray images. Our prototype implementation is capable of performing interactive rate shape editing. The biplane reconstructions of both femur and vertebrae show a good accuracy when compared to CT-scan.
  Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 02/2008; 2008:3967-70.
• Article: Comparative study of scoliotic spines using a fast 3D reconstruction method from biplanar X-rays

  L. Humbert, J. A. De Guise, B. Godbout, S. Parent, J. Dubousset, W. Skalli
  Computer Methods in Biomechanics and Biomedical Engineering - COMPUT METHODS BIOMECH BIOMED. 01/2008; 11:117-118.
• Article: 3D reconstruction of the pelvis from bi-planar radiography.

  D Mitton, S Deschênes, S Laporte, B Godbout, S Bertrand, J A de Guise, W Skalli
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  ABSTRACT: 3D personalized models are more and more requested for clinical and biomechanical studies. Techniques based on bi-planar X-rays present the advantage of a low radiation dose for the patient. However, up to now, such techniques have shown limited accuracy in the case of pelvis reconstruction. This study proposes and validates a method providing accurate 3D personalized model of the pelvis from bi-planar X-rays. The algorithm is based on the fast computation of an initial solution followed by local deformations based on 2D anatomical points and contours that are digitized in both radiographs. Results were close to CT-scan reconstructions (mean difference 1.6 mm and differences under 4.3 mm for 95% of the points). Moreover, 3D morphometry of the pelvis could be obtained with an accuracy of 5%. This technique provides 3D patient specific model with a low radiation dose.
  Computer Methods in Biomechanics and Biomedical Engineering 03/2006; 9(1):1-5. · 0.85 Impact Factor
• Article: Reliability of a quantification imaging system using magnetic resonance images to measure cartilage thickness and volume in human normal and osteoarthritic knees.

  J-P Raynauld, C Kauffmann, G Beaudoin, M-J Berthiaume, J A de Guise, D A Bloch, F Camacho, B Godbout, R D Altman, M Hochberg, J M Meyer, G Cline, J-P Pelletier, J Martel-Pelletier
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  ABSTRACT: The aim of this study was to evaluate the reliability of a software tool that assesses knee cartilage volumes using magnetic resonance (MR) images. The objectives were to assess measurement reliability by: (1) determining the differences between readings of the same image made by the same reader 2 weeks apart (test-retest reliability), (2) determining the differences between the readings of the same image made by different readers (between-reader agreement), and (3) determining the differences between the cartilage volume readings obtained from two MR images of the same knee image acquired a few hours apart (patient positioning reliability). Forty-eight MR examinations of the knee from normal subjects, patients with different stages of symptomatic knee osteoarthritis (OA), and a subset of duplicate images were independently and blindly quantified by three readers using the imaging system. The following cartilage areas were analyzed to compute volumes: global cartilage, medial and lateral compartments, and medial and lateral femoral condyles. Between-reader agreement of measurements was excellent, as shown by intra-class correlation (ICC) coefficients ranging from 0.958 to 0.997 for global cartilage (P<0.0001), 0.974 to 0.998 for the compartments (P<0.0001), and 0.943 to 0.999 for the condyles(P<0.0001). Test-retest reliability of within-reader data was also excellent, with Pearson correlation coefficients ranging from 0.978 to 0.999 (P<0.0001). Patient positioning reliability was also excellent, with Pearson correlation coefficients ranging from 0.978 to 0.999 (P<0.0001). The results of this study establish the reliability of this MR imaging system. Test-retest reliability, between-reader agreement, and patient positioning reliability were all extremely high. This study represents a first step in the overall validation of an imaging system designed to follow progression of human knee OA.
  Osteoarthritis and Cartilage 05/2003; 11(5):351-60. · 3.90 Impact Factor
• Article: Reliability of a quantification imaging system using magnetic resonance images to measure cartilage thickness and volume in human normal and osteoarthritic knees

  J.-P. Raynauld, C. Kauffmann, G. Beaudoin, M.-J. Berthiaume, J.A. de Guise, D.A. Bloch, F. Camacho, B. Godbout, R.D. Altman, M. Hochberg, J.M. Meyer, G. Cline, J.-P. Pelletier, J. Martel-Pelletier
  [show abstract] [hide abstract]
  ABSTRACT: Objective: The aim of this study was to evaluate the reliability of a software tool that assesses knee cartilage volumes using magnetic resonance (MR) images. The objectives were to assess measurement reliability by: (1) determining the differences between readings of the same image made by the same reader 2 weeks apart (test–retest reliability), (2) determining the differences between the readings of the same image made by different readers (between-reader agreement), and (3) determining the differences between the cartilage volume readings obtained from two MR images of the same knee image acquired a few hours apart (patient positioning reliability).Methods: Forty-eight MR examinations of the knee from normal subjects, patients with different stages of symptomatic knee osteoarthritis (OA), and a subset of duplicate images were independently and blindly quantified by three readers using the imaging system. The following cartilage areas were analyzed to compute volumes: global cartilage, medial and lateral compartments, and medial and lateral femoral condyles.Results: Between-reader agreement of measurements was excellent, as shown by intra-class correlation (ICC) coefficients ranging from 0.958 to 0.997 for global cartilage (P<0.0001), 0.974 to 0.998 for the compartments (P<0.0001), and 0.943 to 0.999 for the condyles(P<0.0001). Test–retest reliability of within-reader data was also excellent, with Pearson correlation coefficients ranging from 0.978 to 0.999 (P<0.0001). Patient positioning reliability was also excellent, with Pearson correlation coefficients ranging from 0.978 to 0.999 (P<0.0001).Conclusions: The results of this study establish the reliability of this MR imaging system. Test–retest reliability, between-reader agreement, and patient positioning reliability were all extremely high. This study represents a first step in the overall validation of an imaging system designed to follow progression of human knee OA.
  Osteoarthritis and Cartilage.