The Experts below are selected from a list of 114 Experts worldwide ranked by ideXlab platform

Koenraad Verstraete - One of the best experts on this subject based on the ideXlab platform.

  • magnetic resonance imaging of the medial extremity of the clavicle in forensic Bone Age Determination a new four minute approach
    European Radiology, 2011
    Co-Authors: Elke Hillewig, J De Tobel, O Cuche, P Vandemaele, Michel Piette, Koenraad Verstraete
    Abstract:

    Objectives The use of 3T magnetic resonance imaging (MRI) of the clavicle in forensic Bone Age Determination was prospectively examined and compared with plain radiography.

  • magnetic resonance imaging of the medial extremity of the clavicle in forensic Bone Age Determination a new four minute approach
    European Radiology, 2011
    Co-Authors: Elke Hillewig, J De Tobel, O Cuche, P Vandemaele, Michel Piette, Koenraad Verstraete
    Abstract:

    The use of 3T magnetic resonance imaging (MRI) of the clavicle in forensic Bone Age Determination was prospectively examined and compared with plain radiography. Four MRI sequences and three radiographs of 121 healthy subjects between 11 and 30 were studied by two observers. The number of imAges assessable for Bone Age Determination was lower for plain radiography (PA: 68.7%; oblique: 97.5%) compared with MRI (VIBE: 99.0%). Concerning the subjective level of difficulty to assess Bone Age, the observers found it easier to assess Bone Age on MRI than on radiography. The developmental stAges of the clavicle, as used on plain radiography, were transferable to MRI. Especially the VIBE gradient echo sequence provided an excellent depiction of the growth cartilAge and ossification centre with a slice thickness of 0.9 mm and only a 4-min acquisition time. When the developmental stAges were assigned, less variability between the observers was seen on MRI, compared with plain radiography. We conclude that 3T MRI provides high resolution, cross-sectional imAges of the maturation of the clavicle without ionising radiation in a very short time, allowing more accurate Determination of Bone Age than plain radiography.

Torsten Tuvemo - One of the best experts on this subject based on the ideXlab platform.

  • can the tw3 Bone Age Determination method provide additional criteria for growth hormone treatment in adopted girls with early puberty a comparison of the tanner whitehouse 3 method with the greulich pyle and the tanner whitehouse 2 methods
    Hormone Research in Paediatrics, 2010
    Co-Authors: Lemm A Proos, T Lonnerholm, Bjorn Jonsson, Torsten Tuvemo
    Abstract:

    Background/Aims: Gonadotropin-releasing hormone analogues (GnRHa) are the accepted treatment of idiopathic central precocious puberty. As it has been found that growth velocity may

  • can Bone Age Determination provide criteria for growth hormone treatment in adopted girls with early puberty
    Upsala Journal of Medical Sciences, 2006
    Co-Authors: Lemm A Proos, T Lonnerholm, Bjorn Jonsson, Torsten Tuvemo
    Abstract:

    In treatment of idiopathic central precocious puberty, GnRH analogues (GnRHa) have been accepted as the treatment of choice. Since growth velocity may be impaired with GnRHa treatment growth hormone (GH) treatment has been added in clinical trials. Recently, a study followed adopted girls with early or precocious puberty on GnRHa or combined GnRHa and GH treatment to final height. It was found that final height was significantly higher in the combined treatment group, although the difference was small. It was seen that patients that were extremely short at arrival and short at start of treatment seemed to be candidates for combined treatment. We have now analysed the data in order to define criteria for the sub-group in need of combined GnRHa-GH treatment in order to achieve normal final height, i.e. above -2 SDS. Bone Ages of 46 patients at start of treatment, randomized to either GnRHa treatment or GnRHa treatment combined with GH, were examined blindly by the same radiologist and the PAH calculated. The methods according to Greulich-Pyle / Bayley-Pinneau (GP/BP) and Tanner-Whitehouse (TW2) were used. Predictions versus final height data were analysed. The accuracy of FH prediction was greatest for GnRHa treated group using the GP/BP method. The GP/BP method gave useful cut off limits for when combined treatment was necessary to possibly achieve normal height. If pre-treatment GP/PAH was > 157cm, the patients attained normal height with GnRHa treatment only. Ten out of 13 (77%) such girls could be correctly identified. Using TW2 with a cut off of 164 cm, 9 out of 13 could be selected. Using a multi regression equation of best fit the number of correctly selected cases for GnRHa treatment only, could not be further increased in this group. We conclude that Bone Age Determination and adult height prediction with the Greulich-Pyle/Bayley-Pinneau method, provides useful criteria for selecting the subgroup of adopted girls with early puberty where combined treatment with GnRHa and GH is not necessary to reach normal final height.

Hans Henrik Thodberg - One of the best experts on this subject based on the ideXlab platform.

  • validation of adult height prediction based on automated Bone Age Determination in the paris longitudinal study of healthy children
    Pediatric Radiology, 2016
    Co-Authors: David D Martin, Jan Schittenhelm, Hans Henrik Thodberg
    Abstract:

    An adult height prediction model based on automated Determination of Bone Age was developed and validated in two studies from Zurich, Switzerland. Varied living conditions and genetic backgrounds might make the model less accurate. To validate the adult height prediction model on children from another geographical location. We included 51 boys and 58 girls from the Paris Longitudinal Study of children born 1953 to 1958. Radiographs were obtained once or twice a year in these children from birth to Age 18. Bone Age was determined using the BoneXpert method. Radiographs in children with Bone Age greater than 6 years were considered, in total 1,124 imAges. The root mean square deviation between the predicted and the observed adult height was 2.8 cm for boys in the Bone Age range 6–15 years and 3.1 cm for girls in the Bone Age range 6–13 years. The bias (the averAge signed difference) was zero, except for girls below Bone Age 12, where the predictions were 0.8 cm too low. The accuracy of the BoneXpert method in terms of root mean square error was as predicted by the model, i.e. in line with what was observed in the Zurich studies.

  • automated Determination of Bone Age in a modern chinese population
    International Scholarly Research Notices, 2013
    Co-Authors: Shaoyan Zhang, Gang Liu, Yisan Han, Xunzhang Shen, Hans Henrik Thodberg
    Abstract:

    Rationale and Objective. Large studies have previously been performed to set up a Chinese Bone Age reference, but it has been difficult to compare the maturation of Chinese children with populations elsewhere due to the potential variability between raters in different parts of the world. We re-analysed the radiographs from a large study of normal Chinese children using an automated Bone Age rating method to establish a Chinese Bone Age reference, and to compare the tempo of maturation in the Chinese with other populations. Materials and Methods. X-rays from 2883 boys and 3143 girls Aged 2–20 years from five Chinese cities, taken in 2005, were evaluated using the BoneXpert automated method. Results. Chinese children reached full maturity at the same Age as previously studied Asian children from Los Angeles, but 0.6 years earlier than Caucasian children in Los Angeles. The Greulich-Pyle Bone Age method was adapted to the Chinese population creating a new Bone Age scale BX-China05. The standard deviation between BX-China05 and chronologic Age was 1.01 years in boys Aged 8–14, and 1.08 years in girls Aged 7–12. Conclusion. By eliminating rater variability, the automated method provides a reliable and efficient standard for Bone Age Determination in China.

  • validation and reference values of automated Bone Age Determination for four ethnicities
    Academic Radiology, 2010
    Co-Authors: Hans Henrik Thodberg, Lars Savendahl
    Abstract:

    Rationale and Objectives Bone Age (BA) rating is associated with a considerable rater variability, which would be eliminated with an automated computerized method. The aim of the study was to validate the BoneXpert method, an automated Determination of BA, in American children of four ethnicities. Materials and Methods The study is based on a publicly available database of hand x-rays of healthy children, established in a previous, National Institutes of Health–funded study. Radiographs of the left hand were recorded between 1993 and 2006 in Los Angeles, including 1100 imAges with two independent manual BA ratings and 280 additional imAges for which the manual ratings were not used. ImAges were evenly split between Caucasian, African American, Hispanic, and Asian children, and the Age range was 0–18.99 years. Results The automated method analyzed all imAges with BA >2.5 years for boys and >2 years for girls. The root-mean-square (RMS) error between the two manual ratings was 0.63 years, whereas the RMS deviation between the automated BA and the averAge of the two manual ratings was 0.61 years. The mean BA minus Age was computed versus Age for each sex and ethnicity. The largest deviation from zero was seen for Hispanic and Asian children older than 12 years, who were about 1 year advanced relative to the Greulich and Pyle standard. Conclusion The automated method can analyze imAges of all ethnicities within a BA range of 2.5–17 years for boys and 2–15 years for girls, and can therefore eliminate the problem with rater variability in BA rating.

  • prediction of adult height based on automated Determination of Bone Age
    The Journal of Clinical Endocrinology and Metabolism, 2009
    Co-Authors: Hans Henrik Thodberg, Michael B Ranke, Oskar G Jenni, Jon Caflisch, David D Martin
    Abstract:

    Context: Adult height prediction is a common procedure in pediatric endocrinology, but it is associated with a considerable variability and bias from the Bone Age rating. Objective: A new method for adult height prediction is presented, based on automated Bone Age Determination. Method: The method predicts the fraction of height left to grow from Age and BoneXpert Bone Age. This is refined by drawing the prediction toward the population mean, or alternatively toward the height predicted from the parents’ heights. Boys’ body mass index and girls’ height at menarche can be included optionally as predictors. Participants: A total of 231 normal children from the First Zurich Longitudinal Study (1ZLS) were followed from Age 5 until cessation of growth with annual x-rays of the left hand. A total of 198 normal children from the Third Zurich Longitudinal Study were used for validation. Results: The root mean square error of adult height prediction (Tanner-Whitehouse 3 method in parentheses considered as standard...

  • clinical application of automated greulich pyle Bone Age Determination in children with short stature
    Pediatric Radiology, 2009
    Co-Authors: David D Martin, Hans Henrik Thodberg, Gerhard Binder, Dorothee Deusch, Roland Schweizer, Michael B Ranke
    Abstract:

    Bone Age (BA) rating is time consuming and highly rater dependent. To adjust the fully automated BoneXpert method to agree with the manual Greulich and Pyle BA (GP BA) ratings of five raters and to validate the accuracy for short children. A total of 1,097 left hand radiographs from 188 children with short stature, including growth hormone deficiency (44%) and Turner syndrome (29%) were evaluated. BoneXpert rejected 14 of the 1,097 radiographs, and deviated by more than 1.9 years from the operator BA for 27 radiographs. These were rerated blindly by four operators. Of the 27 new ratings, 26 were within 1.9 years of the automatic BA values. The root mean square deviation between manual and automatic rating was 0.72 years (95% CI 0.69–0.75). BoneXpert’s ability to process 99% of imAges automatically without errors, and to obtain good agreement with an operator suggests that the method is efficient and reliable for short children.

David D Martin - One of the best experts on this subject based on the ideXlab platform.

  • validation of adult height prediction based on automated Bone Age Determination in the paris longitudinal study of healthy children
    Pediatric Radiology, 2016
    Co-Authors: David D Martin, Jan Schittenhelm, Hans Henrik Thodberg
    Abstract:

    An adult height prediction model based on automated Determination of Bone Age was developed and validated in two studies from Zurich, Switzerland. Varied living conditions and genetic backgrounds might make the model less accurate. To validate the adult height prediction model on children from another geographical location. We included 51 boys and 58 girls from the Paris Longitudinal Study of children born 1953 to 1958. Radiographs were obtained once or twice a year in these children from birth to Age 18. Bone Age was determined using the BoneXpert method. Radiographs in children with Bone Age greater than 6 years were considered, in total 1,124 imAges. The root mean square deviation between the predicted and the observed adult height was 2.8 cm for boys in the Bone Age range 6–15 years and 3.1 cm for girls in the Bone Age range 6–13 years. The bias (the averAge signed difference) was zero, except for girls below Bone Age 12, where the predictions were 0.8 cm too low. The accuracy of the BoneXpert method in terms of root mean square error was as predicted by the model, i.e. in line with what was observed in the Zurich studies.

  • validation of automatic Bone Age Determination in children with congenital adrenal hyperplasia
    Pediatric Radiology, 2013
    Co-Authors: David D Martin, Katharina Heil, C Heckmann, Angelika Zierl, Jurgen F Schaefer, Michael B Ranke, Gerhard Binder
    Abstract:

    Background Determination of Bone Age is routinely used for following up substitution therapy in congenital adrenal hyperplasia (CAH) but today is a procedure with significant subjectivity.

  • prediction of adult height based on automated Determination of Bone Age
    The Journal of Clinical Endocrinology and Metabolism, 2009
    Co-Authors: Hans Henrik Thodberg, Michael B Ranke, Oskar G Jenni, Jon Caflisch, David D Martin
    Abstract:

    Context: Adult height prediction is a common procedure in pediatric endocrinology, but it is associated with a considerable variability and bias from the Bone Age rating. Objective: A new method for adult height prediction is presented, based on automated Bone Age Determination. Method: The method predicts the fraction of height left to grow from Age and BoneXpert Bone Age. This is refined by drawing the prediction toward the population mean, or alternatively toward the height predicted from the parents’ heights. Boys’ body mass index and girls’ height at menarche can be included optionally as predictors. Participants: A total of 231 normal children from the First Zurich Longitudinal Study (1ZLS) were followed from Age 5 until cessation of growth with annual x-rays of the left hand. A total of 198 normal children from the Third Zurich Longitudinal Study were used for validation. Results: The root mean square error of adult height prediction (Tanner-Whitehouse 3 method in parentheses considered as standard...

  • clinical application of automated greulich pyle Bone Age Determination in children with short stature
    Pediatric Radiology, 2009
    Co-Authors: David D Martin, Hans Henrik Thodberg, Gerhard Binder, Dorothee Deusch, Roland Schweizer, Michael B Ranke
    Abstract:

    Bone Age (BA) rating is time consuming and highly rater dependent. To adjust the fully automated BoneXpert method to agree with the manual Greulich and Pyle BA (GP BA) ratings of five raters and to validate the accuracy for short children. A total of 1,097 left hand radiographs from 188 children with short stature, including growth hormone deficiency (44%) and Turner syndrome (29%) were evaluated. BoneXpert rejected 14 of the 1,097 radiographs, and deviated by more than 1.9 years from the operator BA for 27 radiographs. These were rerated blindly by four operators. Of the 27 new ratings, 26 were within 1.9 years of the automatic BA values. The root mean square deviation between manual and automatic rating was 0.72 years (95% CI 0.69–0.75). BoneXpert’s ability to process 99% of imAges automatically without errors, and to obtain good agreement with an operator suggests that the method is efficient and reliable for short children.

Elke Hillewig - One of the best experts on this subject based on the ideXlab platform.

  • magnetic resonance imaging of the medial extremity of the clavicle in forensic Bone Age Determination a new four minute approach
    European Radiology, 2011
    Co-Authors: Elke Hillewig, J De Tobel, O Cuche, P Vandemaele, Michel Piette, Koenraad Verstraete
    Abstract:

    Objectives The use of 3T magnetic resonance imaging (MRI) of the clavicle in forensic Bone Age Determination was prospectively examined and compared with plain radiography.

  • magnetic resonance imaging of the medial extremity of the clavicle in forensic Bone Age Determination a new four minute approach
    European Radiology, 2011
    Co-Authors: Elke Hillewig, J De Tobel, O Cuche, P Vandemaele, Michel Piette, Koenraad Verstraete
    Abstract:

    The use of 3T magnetic resonance imaging (MRI) of the clavicle in forensic Bone Age Determination was prospectively examined and compared with plain radiography. Four MRI sequences and three radiographs of 121 healthy subjects between 11 and 30 were studied by two observers. The number of imAges assessable for Bone Age Determination was lower for plain radiography (PA: 68.7%; oblique: 97.5%) compared with MRI (VIBE: 99.0%). Concerning the subjective level of difficulty to assess Bone Age, the observers found it easier to assess Bone Age on MRI than on radiography. The developmental stAges of the clavicle, as used on plain radiography, were transferable to MRI. Especially the VIBE gradient echo sequence provided an excellent depiction of the growth cartilAge and ossification centre with a slice thickness of 0.9 mm and only a 4-min acquisition time. When the developmental stAges were assigned, less variability between the observers was seen on MRI, compared with plain radiography. We conclude that 3T MRI provides high resolution, cross-sectional imAges of the maturation of the clavicle without ionising radiation in a very short time, allowing more accurate Determination of Bone Age than plain radiography.