The Experts below are selected from a list of 9603 Experts worldwide ranked by ideXlab platform
Sabine Heiland - One of the best experts on this subject based on the ideXlab platform.
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in vivo comparison of mri and cbct based 3d Cephalometric Analysis beginning of a non ionizing diagnostic era in craniomaxillofacial imaging
European Radiology, 2020Co-Authors: Alexander Juerchott, Martin Bendszus, Sabine Heiland, Christopher J. Lux, Sebastian Zingler, Christian Freudlsperger, Dorothea Weber, Johann M E Jende, Muhammad Abdullah Saleem, Tim HilgenfeldAbstract:To evaluate whether magnetic resonance imaging (MRI) can serve as an alternative diagnostic tool to the “gold standard” cone-beam computed tomography (CBCT) in 3D Cephalometric Analysis. In this prospective feasibility study, 12 patients (8 males, 4 females; mean age ± SD, 26.1 years ± 6.6) underwent 3D MRI and CBCT before orthognathic surgery. 3D Cephalometric Analysis was performed twice by two independent observers on both modalities. For each dataset, 27 Cephalometric landmarks were defined from which 35 measurements (17 angles, 18 distances) were calculated. Statistical analyses included the calculation of Euclidean distances, intraclass correlation coefficients (ICCs), Bland-Altman Analysis, and equivalence testing (linear mixed effects model) with a predefined equivalence margin of ± 1°/1 mm. Analysis of reliability for CBCT vs. MRI (intra-rater I/intra-rater II/inter-rater) revealed Euclidean distances of 0.86/0.86/0.98 mm vs. 0.93/0.99/1.10 mm for landmarks, ICCs of 0.990/0.980/0.986 vs. 0.982/0.978/0.980 for angles, and ICCs of 0.992/0.988/0.989 vs. 0.991/0.985/0.988 for distances. Bland-Altman Analysis showed high levels of agreement between CBCT and MRI with bias values (95% levels of agreement) of 0.03° (− 1.49; 1.54) for angles and 0.02 mm (− 1.44; 1.47) for distances. In the linear mixed effects model, the mean values of CBCT and MRI measurements were equivalent. This feasibility study indicates that MRI enables reliable 3D Cephalometric Analysis with excellent agreement to corresponding measurements on CBCT. Thus, MRI could serve as a non-ionizing alternative to CBCT for treatment planning and monitoring in orthodontics as well as oral and maxillofacial surgery. • Clinically established 3D Cephalometric measurements performed on MRI are highly reliable and show an excellent agreement with CBCT (gold standard). • The MRI technique applied in this study could be used as a non-ionizing diagnostic tool in orthodontics as well as oral and maxillofacial surgery. • Since most patients benefiting from 3D cephalometry are young in age, the use of MRI could substantially contribute to radiation protection and open up new possibilities for treatment monitoring.
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3d Cephalometric Analysis using magnetic resonance imaging validation of accuracy and reproducibility
Scientific Reports, 2018Co-Authors: Alexander Juerchott, Tim Hilgenfeld, Martin Bendszus, Christopher J. Lux, Sebastian Zingler, Christian Freudlsperger, Muhammad Abdullah Saleem, Sabine HeilandAbstract:The aim of this study was to validate geometric accuracy and in vivo reproducibility of landmark-based Cephalometric measurements using high-resolution 3D Magnetic Resonance Imaging (MRI) at 3 Tesla. For accuracy validation, 96 angular and 96 linear measurements were taken on a phantom in 3 different positions. In vivo MRI scans were performed on 3 volunteers in five head positions. For each in vivo scan, 27 landmarks were determined from which 19 angles and 26 distances were calculated. Statistical Analysis was performed using Bland-Altman Analysis, the two one-sided tests procedure and repeated measures one-way Analysis of variance. In comparison to ground truth, all MRI-based phantom measurements showed statistical equivalence (p 0.05). Ranges between maximum and minimum in vivo values were consistently smaller than 2° and 2 mm, respectively (average ranges: 0.88°/0.87 mm). In conclusion, this study demonstrates that accurate and reproducible 3D Cephalometric Analysis can be performed without exposure to ionizing radiation using MRI.
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lateral Cephalometric Analysis for treatment planning in orthodontics based on mri compared with radiographs a feasibility study in children and adolescents
PLOS ONE, 2017Co-Authors: Alexander Heil, Eduardo Lazo Gonzalez, Tim Hilgenfeld, Philipp Kickingereder, Martin Bendszus, Sabine Heiland, Ann-kathrin Ozga, Andreas Sommer, Christopher J. Lux, Sebastian ZinglerAbstract:Objective The objective of this prospective study was to evaluate whether magnetic resonance imaging (MRI) is equivalent to lateral Cephalometric radiographs (LCR, “gold standard”) in Cephalometric Analysis. Methods The applied MRI technique was optimized for short scanning time, high resolution, high contrast and geometric accuracy. Prior to orthodontic treatment, 20 patients (mean age ± SD, 13.95 years ± 5.34) received MRI and LCR. MRI datasets were postprocessed into lateral cephalograms. Cephalometric Analysis was performed twice by two independent observers for both modalities with an interval of 4 weeks. Eight bilateral and 10 midsagittal landmarks were identified, and 24 widely used measurements (14 angles, 10 distances) were calculated. Statistical Analysis was performed by using intraclass correlation coefficient (ICC), Bland-Altman Analysis and two one-sided tests (TOST) within the predefined equivalence margin of ± 2°/mm. Results Geometric accuracy of the MRI technique was confirmed by phantom measurements. Mean intraobserver ICC were 0.977/0.975 for MRI and 0.975/0.961 for LCR. Average interobserver ICC were 0.980 for MRI and 0.929 for LCR. Bland-Altman Analysis showed high levels of agreement between the two modalities, bias range (mean ± SD) was -0.66 to 0.61 mm (0.06 ± 0.44) for distances and -1.33 to 1.14° (0.06 ± 0.71) for angles. Except for the interincisal angle (p = 0.17) all measurements were statistically equivalent (p < 0.05). Conclusions This study demonstrates feasibility of orthodontic treatment planning without radiation exposure based on MRI. High-resolution isotropic MRI datasets can be transformed into lateral cephalograms allowing reliable measurements as applied in orthodontic routine with high concordance to the corresponding measurements on LCR.
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Workflow applied in the present study for each patient (n = 20) is shown.
2017Co-Authors: Alexander Heil, Eduardo Lazo Gonzalez, Tim Hilgenfeld, Philipp Kickingereder, Martin Bendszus, Sabine Heiland, Ann-kathrin Ozga, Andreas Sommer, Christopher J. Lux, Sebastian ZinglerAbstract:I = A multiplanar reconstruction (MPR) along the anatomic sagittal plane was acquired from primary magnetic resonance imaging (MRI) datasets. II = The midsagittal plane is coloured in red for better visualization of the workflow. Nine slices containing the landmarks necessary for Cephalometric Analysis were selected (1). The paired lateral slices were cropped preserving the relevant landmarks on the left (2a) and right (2b) side. The midsagittal plane and the 8 cropped lateral slices were merged into a lateral MRI cephalogram (3). III = Lateral Cephalometric Analysis was performed on lateral MRI cephalograms and corresponding lateral Cephalometric radiographs (LCR) with dedicated software. For each modality two observers placed 10 midsagittal and 8 bilateral landmarks from which 14 angles and 10 distances were calculated automatically by software. Measurements were taken twice with an interval of 4 weeks.
V. Lanteri - One of the best experts on this subject based on the ideXlab platform.
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comparison of a tridimensional Cephalometric Analysis performed on 3t mri compared with cbct a pilot study in adults
Progress in Orthodontics, 2019Co-Authors: C. Maspero, A. Abate, F. Bellincioni, D. Cavagnetto, V. LanteriAbstract:Since the introduction of cone-beam computed tomography (CBCT) in dentistry, this technology has enabled distortion-free three-dimensional Cephalometric Analysis for orthodontic and orthognathic surgery diagnosis. However, CBCT is associated with significantly higher radiation exposure than traditional routine bidimensional examinations for orthodontic diagnosis, although low-dose protocols have markedly reduced radiation exposure over time. The objective of this preliminary feasibility study is to compare the accuracy and diagnostic capabilities of an already-validated three-dimensional Cephalometric Analysis on CBCT to those of an Analysis on 3-T magnetic resonance imaging (3T-MRI) to assess whether the latter can deliver a comparable quality of information while avoiding radiation exposure. In order to test the feasibility of three-dimensional cephalometry on 3T-MRI, 18 subjects (4 male; 14 female) with mean age 37.8 ± SD 10.2, who had undergone both maxillofacial CBCT and maxillofacial 3T-MRI for various purposes within 1 month, were selected from the archive of the Department of Dentistry and Maxillofacial Surgery of Fondazione Ospedale Policlinico Maggiore, IRCCS, Milano, Italy. A three-dimensional Cephalometric Analysis composed of ten midsagittal and four bilateral landmarks and 24 measurements (11 angular, 13 linear) was performed on both scans using Mimics Research® v. 17.0 (NV, Technologielaan 15, 3001 Leuven, Belgium). Cephalometric Analysis was performed twice by two independent orthodontists for each scan, and each orthodontist repeated the measurements 3 weeks later. Statistical Analysis was performed with SPSS® 20.00 for Windows (IBM® Corporation, Sommers, NY, USA). A Bland-Altman test for each Cephalometric value was performed to assess the agreement between the procedures. The intraclass correlation coefficient (ICC) was used to assess interobserver and intraobserver reliability. The coefficient of variation was used to evaluate precision. Both procedures showed good reliability, with mean intraobserver ICCs of 0.977/0.971 for CBCT and 0.881/0.912 for MRI. The average interobserver ICCs were 0.965 for CBCT and 0.833 for MRI. A Bland-Altman Analysis for the Cephalometric tracing revealed a similar range of agreement between the two modalities; the bias range (mean ± SD) was − 0.25–0.66 mm (0.174 ± 0.31) for distances and − 0.41–0.54° (0.12 ± 0.33) for angles. Within the main limitation of this pilot study, that is, the small sample, it is possible to state that Cephalometric measurements on 3T-MRI seem to possess adequate reliability and repeatability and that they show satisfying agreement with values measured on CBCTs. An MRI examination does not expose patients to ionizing radiation and could provide an alternative to CBCT for three-dimensional Cephalometrics in the future.
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Comparison of a tridimensional Cephalometric Analysis performed on 3T-MRI compared with CBCT : a pilot study in adults
'Springer Science and Business Media LLC', 2019Co-Authors: C. Maspero, A. Abate, F. Bellincioni, D. Cavagnetto, V. Lanteri, A. Costa, M. FarronatoAbstract:OBJECTIVE: Since the introduction of cone-beam computed tomography (CBCT) in dentistry, this technology has enabled distortion-free three-dimensional Cephalometric Analysis for orthodontic and orthognathic surgery diagnosis. However, CBCT is associated with significantly higher radiation exposure than traditional routine bidimensional examinations for orthodontic diagnosis, although low-dose protocols have markedly reduced radiation exposure over time. The objective of this preliminary feasibility study is to compare the accuracy and diagnostic capabilities of an already-validated three-dimensional Cephalometric Analysis on CBCT to those of an Analysis on 3-T magnetic resonance imaging (3T-MRI) to assess whether the latter can deliver a comparable quality of information while avoiding radiation exposure. MATERIALS AND METHODS: In order to test the feasibility of three-dimensional cephalometry on 3T-MRI, 18 subjects (4 male; 14 female) with mean age 37.8\u2009\ub1\u2009SD 10.2, who had undergone both maxillofacial CBCT and maxillofacial 3T-MRI for various purposes within 1 month, were selected from the archive of the Department of Dentistry and Maxillofacial Surgery of Fondazione Ospedale Policlinico Maggiore, IRCCS, Milano, Italy. A three-dimensional Cephalometric Analysis composed of ten midsagittal and four bilateral landmarks and 24 measurements (11 angular, 13 linear) was performed on both scans using Mimics Research\uae v. 17.0 (NV, Technologielaan 15, 3001 Leuven, Belgium). Cephalometric Analysis was performed twice by two independent orthodontists for each scan, and each orthodontist repeated the measurements 3 weeks later. Statistical Analysis was performed with SPSS\uae 20.00 for Windows (IBM\uae Corporation, Sommers, NY, USA). A Bland-Altman test for each Cephalometric value was performed to assess the agreement between the procedures. The intraclass correlation coefficient (ICC) was used to assess interobserver and intraobserver reliability. The coefficient of variation was used to evaluate precision. RESULTS: Both procedures showed good reliability, with mean intraobserver ICCs of 0.977/0.971 for CBCT and 0.881/0.912 for MRI. The average interobserver ICCs were 0.965 for CBCT and 0.833 for MRI. A Bland-Altman Analysis for the Cephalometric tracing revealed a similar range of agreement between the two modalities; the bias range (mean\u2009\ub1\u2009SD) was -\u20090.25-0.66\u2009mm (0.174\u2009\ub1\u20090.31) for distances and -\u20090.41-0.54\ub0 (0.12\u2009\ub1\u20090.33) for angles. CONCLUSIONS: Within the main limitation of this pilot study, that is, the small sample, it is possible to state that Cephalometric measurements on 3T-MRI seem to possess adequate reliability and repeatability and that they show satisfying agreement with values measured on CBCTs. An MRI examination does not expose patients to ionizing radiation and could provide an alternative to CBCT for three-dimensional Cephalometrics in the future
Tim Hilgenfeld - One of the best experts on this subject based on the ideXlab platform.
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in vivo comparison of mri and cbct based 3d Cephalometric Analysis beginning of a non ionizing diagnostic era in craniomaxillofacial imaging
European Radiology, 2020Co-Authors: Alexander Juerchott, Martin Bendszus, Sabine Heiland, Christopher J. Lux, Sebastian Zingler, Christian Freudlsperger, Dorothea Weber, Johann M E Jende, Muhammad Abdullah Saleem, Tim HilgenfeldAbstract:To evaluate whether magnetic resonance imaging (MRI) can serve as an alternative diagnostic tool to the “gold standard” cone-beam computed tomography (CBCT) in 3D Cephalometric Analysis. In this prospective feasibility study, 12 patients (8 males, 4 females; mean age ± SD, 26.1 years ± 6.6) underwent 3D MRI and CBCT before orthognathic surgery. 3D Cephalometric Analysis was performed twice by two independent observers on both modalities. For each dataset, 27 Cephalometric landmarks were defined from which 35 measurements (17 angles, 18 distances) were calculated. Statistical analyses included the calculation of Euclidean distances, intraclass correlation coefficients (ICCs), Bland-Altman Analysis, and equivalence testing (linear mixed effects model) with a predefined equivalence margin of ± 1°/1 mm. Analysis of reliability for CBCT vs. MRI (intra-rater I/intra-rater II/inter-rater) revealed Euclidean distances of 0.86/0.86/0.98 mm vs. 0.93/0.99/1.10 mm for landmarks, ICCs of 0.990/0.980/0.986 vs. 0.982/0.978/0.980 for angles, and ICCs of 0.992/0.988/0.989 vs. 0.991/0.985/0.988 for distances. Bland-Altman Analysis showed high levels of agreement between CBCT and MRI with bias values (95% levels of agreement) of 0.03° (− 1.49; 1.54) for angles and 0.02 mm (− 1.44; 1.47) for distances. In the linear mixed effects model, the mean values of CBCT and MRI measurements were equivalent. This feasibility study indicates that MRI enables reliable 3D Cephalometric Analysis with excellent agreement to corresponding measurements on CBCT. Thus, MRI could serve as a non-ionizing alternative to CBCT for treatment planning and monitoring in orthodontics as well as oral and maxillofacial surgery. • Clinically established 3D Cephalometric measurements performed on MRI are highly reliable and show an excellent agreement with CBCT (gold standard). • The MRI technique applied in this study could be used as a non-ionizing diagnostic tool in orthodontics as well as oral and maxillofacial surgery. • Since most patients benefiting from 3D cephalometry are young in age, the use of MRI could substantially contribute to radiation protection and open up new possibilities for treatment monitoring.
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3d Cephalometric Analysis using magnetic resonance imaging validation of accuracy and reproducibility
Scientific Reports, 2018Co-Authors: Alexander Juerchott, Tim Hilgenfeld, Martin Bendszus, Christopher J. Lux, Sebastian Zingler, Christian Freudlsperger, Muhammad Abdullah Saleem, Sabine HeilandAbstract:The aim of this study was to validate geometric accuracy and in vivo reproducibility of landmark-based Cephalometric measurements using high-resolution 3D Magnetic Resonance Imaging (MRI) at 3 Tesla. For accuracy validation, 96 angular and 96 linear measurements were taken on a phantom in 3 different positions. In vivo MRI scans were performed on 3 volunteers in five head positions. For each in vivo scan, 27 landmarks were determined from which 19 angles and 26 distances were calculated. Statistical Analysis was performed using Bland-Altman Analysis, the two one-sided tests procedure and repeated measures one-way Analysis of variance. In comparison to ground truth, all MRI-based phantom measurements showed statistical equivalence (p 0.05). Ranges between maximum and minimum in vivo values were consistently smaller than 2° and 2 mm, respectively (average ranges: 0.88°/0.87 mm). In conclusion, this study demonstrates that accurate and reproducible 3D Cephalometric Analysis can be performed without exposure to ionizing radiation using MRI.
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lateral Cephalometric Analysis for treatment planning in orthodontics based on mri compared with radiographs a feasibility study in children and adolescents
PLOS ONE, 2017Co-Authors: Alexander Heil, Eduardo Lazo Gonzalez, Tim Hilgenfeld, Philipp Kickingereder, Martin Bendszus, Sabine Heiland, Ann-kathrin Ozga, Andreas Sommer, Christopher J. Lux, Sebastian ZinglerAbstract:Objective The objective of this prospective study was to evaluate whether magnetic resonance imaging (MRI) is equivalent to lateral Cephalometric radiographs (LCR, “gold standard”) in Cephalometric Analysis. Methods The applied MRI technique was optimized for short scanning time, high resolution, high contrast and geometric accuracy. Prior to orthodontic treatment, 20 patients (mean age ± SD, 13.95 years ± 5.34) received MRI and LCR. MRI datasets were postprocessed into lateral cephalograms. Cephalometric Analysis was performed twice by two independent observers for both modalities with an interval of 4 weeks. Eight bilateral and 10 midsagittal landmarks were identified, and 24 widely used measurements (14 angles, 10 distances) were calculated. Statistical Analysis was performed by using intraclass correlation coefficient (ICC), Bland-Altman Analysis and two one-sided tests (TOST) within the predefined equivalence margin of ± 2°/mm. Results Geometric accuracy of the MRI technique was confirmed by phantom measurements. Mean intraobserver ICC were 0.977/0.975 for MRI and 0.975/0.961 for LCR. Average interobserver ICC were 0.980 for MRI and 0.929 for LCR. Bland-Altman Analysis showed high levels of agreement between the two modalities, bias range (mean ± SD) was -0.66 to 0.61 mm (0.06 ± 0.44) for distances and -1.33 to 1.14° (0.06 ± 0.71) for angles. Except for the interincisal angle (p = 0.17) all measurements were statistically equivalent (p < 0.05). Conclusions This study demonstrates feasibility of orthodontic treatment planning without radiation exposure based on MRI. High-resolution isotropic MRI datasets can be transformed into lateral cephalograms allowing reliable measurements as applied in orthodontic routine with high concordance to the corresponding measurements on LCR.
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Workflow applied in the present study for each patient (n = 20) is shown.
2017Co-Authors: Alexander Heil, Eduardo Lazo Gonzalez, Tim Hilgenfeld, Philipp Kickingereder, Martin Bendszus, Sabine Heiland, Ann-kathrin Ozga, Andreas Sommer, Christopher J. Lux, Sebastian ZinglerAbstract:I = A multiplanar reconstruction (MPR) along the anatomic sagittal plane was acquired from primary magnetic resonance imaging (MRI) datasets. II = The midsagittal plane is coloured in red for better visualization of the workflow. Nine slices containing the landmarks necessary for Cephalometric Analysis were selected (1). The paired lateral slices were cropped preserving the relevant landmarks on the left (2a) and right (2b) side. The midsagittal plane and the 8 cropped lateral slices were merged into a lateral MRI cephalogram (3). III = Lateral Cephalometric Analysis was performed on lateral MRI cephalograms and corresponding lateral Cephalometric radiographs (LCR) with dedicated software. For each modality two observers placed 10 midsagittal and 8 bilateral landmarks from which 14 angles and 10 distances were calculated automatically by software. Measurements were taken twice with an interval of 4 weeks.
Sebastian Zingler - One of the best experts on this subject based on the ideXlab platform.
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in vivo comparison of mri and cbct based 3d Cephalometric Analysis beginning of a non ionizing diagnostic era in craniomaxillofacial imaging
European Radiology, 2020Co-Authors: Alexander Juerchott, Martin Bendszus, Sabine Heiland, Christopher J. Lux, Sebastian Zingler, Christian Freudlsperger, Dorothea Weber, Johann M E Jende, Muhammad Abdullah Saleem, Tim HilgenfeldAbstract:To evaluate whether magnetic resonance imaging (MRI) can serve as an alternative diagnostic tool to the “gold standard” cone-beam computed tomography (CBCT) in 3D Cephalometric Analysis. In this prospective feasibility study, 12 patients (8 males, 4 females; mean age ± SD, 26.1 years ± 6.6) underwent 3D MRI and CBCT before orthognathic surgery. 3D Cephalometric Analysis was performed twice by two independent observers on both modalities. For each dataset, 27 Cephalometric landmarks were defined from which 35 measurements (17 angles, 18 distances) were calculated. Statistical analyses included the calculation of Euclidean distances, intraclass correlation coefficients (ICCs), Bland-Altman Analysis, and equivalence testing (linear mixed effects model) with a predefined equivalence margin of ± 1°/1 mm. Analysis of reliability for CBCT vs. MRI (intra-rater I/intra-rater II/inter-rater) revealed Euclidean distances of 0.86/0.86/0.98 mm vs. 0.93/0.99/1.10 mm for landmarks, ICCs of 0.990/0.980/0.986 vs. 0.982/0.978/0.980 for angles, and ICCs of 0.992/0.988/0.989 vs. 0.991/0.985/0.988 for distances. Bland-Altman Analysis showed high levels of agreement between CBCT and MRI with bias values (95% levels of agreement) of 0.03° (− 1.49; 1.54) for angles and 0.02 mm (− 1.44; 1.47) for distances. In the linear mixed effects model, the mean values of CBCT and MRI measurements were equivalent. This feasibility study indicates that MRI enables reliable 3D Cephalometric Analysis with excellent agreement to corresponding measurements on CBCT. Thus, MRI could serve as a non-ionizing alternative to CBCT for treatment planning and monitoring in orthodontics as well as oral and maxillofacial surgery. • Clinically established 3D Cephalometric measurements performed on MRI are highly reliable and show an excellent agreement with CBCT (gold standard). • The MRI technique applied in this study could be used as a non-ionizing diagnostic tool in orthodontics as well as oral and maxillofacial surgery. • Since most patients benefiting from 3D cephalometry are young in age, the use of MRI could substantially contribute to radiation protection and open up new possibilities for treatment monitoring.
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3d Cephalometric Analysis using magnetic resonance imaging validation of accuracy and reproducibility
Scientific Reports, 2018Co-Authors: Alexander Juerchott, Tim Hilgenfeld, Martin Bendszus, Christopher J. Lux, Sebastian Zingler, Christian Freudlsperger, Muhammad Abdullah Saleem, Sabine HeilandAbstract:The aim of this study was to validate geometric accuracy and in vivo reproducibility of landmark-based Cephalometric measurements using high-resolution 3D Magnetic Resonance Imaging (MRI) at 3 Tesla. For accuracy validation, 96 angular and 96 linear measurements were taken on a phantom in 3 different positions. In vivo MRI scans were performed on 3 volunteers in five head positions. For each in vivo scan, 27 landmarks were determined from which 19 angles and 26 distances were calculated. Statistical Analysis was performed using Bland-Altman Analysis, the two one-sided tests procedure and repeated measures one-way Analysis of variance. In comparison to ground truth, all MRI-based phantom measurements showed statistical equivalence (p 0.05). Ranges between maximum and minimum in vivo values were consistently smaller than 2° and 2 mm, respectively (average ranges: 0.88°/0.87 mm). In conclusion, this study demonstrates that accurate and reproducible 3D Cephalometric Analysis can be performed without exposure to ionizing radiation using MRI.
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lateral Cephalometric Analysis for treatment planning in orthodontics based on mri compared with radiographs a feasibility study in children and adolescents
PLOS ONE, 2017Co-Authors: Alexander Heil, Eduardo Lazo Gonzalez, Tim Hilgenfeld, Philipp Kickingereder, Martin Bendszus, Sabine Heiland, Ann-kathrin Ozga, Andreas Sommer, Christopher J. Lux, Sebastian ZinglerAbstract:Objective The objective of this prospective study was to evaluate whether magnetic resonance imaging (MRI) is equivalent to lateral Cephalometric radiographs (LCR, “gold standard”) in Cephalometric Analysis. Methods The applied MRI technique was optimized for short scanning time, high resolution, high contrast and geometric accuracy. Prior to orthodontic treatment, 20 patients (mean age ± SD, 13.95 years ± 5.34) received MRI and LCR. MRI datasets were postprocessed into lateral cephalograms. Cephalometric Analysis was performed twice by two independent observers for both modalities with an interval of 4 weeks. Eight bilateral and 10 midsagittal landmarks were identified, and 24 widely used measurements (14 angles, 10 distances) were calculated. Statistical Analysis was performed by using intraclass correlation coefficient (ICC), Bland-Altman Analysis and two one-sided tests (TOST) within the predefined equivalence margin of ± 2°/mm. Results Geometric accuracy of the MRI technique was confirmed by phantom measurements. Mean intraobserver ICC were 0.977/0.975 for MRI and 0.975/0.961 for LCR. Average interobserver ICC were 0.980 for MRI and 0.929 for LCR. Bland-Altman Analysis showed high levels of agreement between the two modalities, bias range (mean ± SD) was -0.66 to 0.61 mm (0.06 ± 0.44) for distances and -1.33 to 1.14° (0.06 ± 0.71) for angles. Except for the interincisal angle (p = 0.17) all measurements were statistically equivalent (p < 0.05). Conclusions This study demonstrates feasibility of orthodontic treatment planning without radiation exposure based on MRI. High-resolution isotropic MRI datasets can be transformed into lateral cephalograms allowing reliable measurements as applied in orthodontic routine with high concordance to the corresponding measurements on LCR.
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Workflow applied in the present study for each patient (n = 20) is shown.
2017Co-Authors: Alexander Heil, Eduardo Lazo Gonzalez, Tim Hilgenfeld, Philipp Kickingereder, Martin Bendszus, Sabine Heiland, Ann-kathrin Ozga, Andreas Sommer, Christopher J. Lux, Sebastian ZinglerAbstract:I = A multiplanar reconstruction (MPR) along the anatomic sagittal plane was acquired from primary magnetic resonance imaging (MRI) datasets. II = The midsagittal plane is coloured in red for better visualization of the workflow. Nine slices containing the landmarks necessary for Cephalometric Analysis were selected (1). The paired lateral slices were cropped preserving the relevant landmarks on the left (2a) and right (2b) side. The midsagittal plane and the 8 cropped lateral slices were merged into a lateral MRI cephalogram (3). III = Lateral Cephalometric Analysis was performed on lateral MRI cephalograms and corresponding lateral Cephalometric radiographs (LCR) with dedicated software. For each modality two observers placed 10 midsagittal and 8 bilateral landmarks from which 14 angles and 10 distances were calculated automatically by software. Measurements were taken twice with an interval of 4 weeks.
C. Maspero - One of the best experts on this subject based on the ideXlab platform.
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comparison of a tridimensional Cephalometric Analysis performed on 3t mri compared with cbct a pilot study in adults
Progress in Orthodontics, 2019Co-Authors: C. Maspero, A. Abate, F. Bellincioni, D. Cavagnetto, V. LanteriAbstract:Since the introduction of cone-beam computed tomography (CBCT) in dentistry, this technology has enabled distortion-free three-dimensional Cephalometric Analysis for orthodontic and orthognathic surgery diagnosis. However, CBCT is associated with significantly higher radiation exposure than traditional routine bidimensional examinations for orthodontic diagnosis, although low-dose protocols have markedly reduced radiation exposure over time. The objective of this preliminary feasibility study is to compare the accuracy and diagnostic capabilities of an already-validated three-dimensional Cephalometric Analysis on CBCT to those of an Analysis on 3-T magnetic resonance imaging (3T-MRI) to assess whether the latter can deliver a comparable quality of information while avoiding radiation exposure. In order to test the feasibility of three-dimensional cephalometry on 3T-MRI, 18 subjects (4 male; 14 female) with mean age 37.8 ± SD 10.2, who had undergone both maxillofacial CBCT and maxillofacial 3T-MRI for various purposes within 1 month, were selected from the archive of the Department of Dentistry and Maxillofacial Surgery of Fondazione Ospedale Policlinico Maggiore, IRCCS, Milano, Italy. A three-dimensional Cephalometric Analysis composed of ten midsagittal and four bilateral landmarks and 24 measurements (11 angular, 13 linear) was performed on both scans using Mimics Research® v. 17.0 (NV, Technologielaan 15, 3001 Leuven, Belgium). Cephalometric Analysis was performed twice by two independent orthodontists for each scan, and each orthodontist repeated the measurements 3 weeks later. Statistical Analysis was performed with SPSS® 20.00 for Windows (IBM® Corporation, Sommers, NY, USA). A Bland-Altman test for each Cephalometric value was performed to assess the agreement between the procedures. The intraclass correlation coefficient (ICC) was used to assess interobserver and intraobserver reliability. The coefficient of variation was used to evaluate precision. Both procedures showed good reliability, with mean intraobserver ICCs of 0.977/0.971 for CBCT and 0.881/0.912 for MRI. The average interobserver ICCs were 0.965 for CBCT and 0.833 for MRI. A Bland-Altman Analysis for the Cephalometric tracing revealed a similar range of agreement between the two modalities; the bias range (mean ± SD) was − 0.25–0.66 mm (0.174 ± 0.31) for distances and − 0.41–0.54° (0.12 ± 0.33) for angles. Within the main limitation of this pilot study, that is, the small sample, it is possible to state that Cephalometric measurements on 3T-MRI seem to possess adequate reliability and repeatability and that they show satisfying agreement with values measured on CBCTs. An MRI examination does not expose patients to ionizing radiation and could provide an alternative to CBCT for three-dimensional Cephalometrics in the future.
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Comparison of a tridimensional Cephalometric Analysis performed on 3T-MRI compared with CBCT : a pilot study in adults
'Springer Science and Business Media LLC', 2019Co-Authors: C. Maspero, A. Abate, F. Bellincioni, D. Cavagnetto, V. Lanteri, A. Costa, M. FarronatoAbstract:OBJECTIVE: Since the introduction of cone-beam computed tomography (CBCT) in dentistry, this technology has enabled distortion-free three-dimensional Cephalometric Analysis for orthodontic and orthognathic surgery diagnosis. However, CBCT is associated with significantly higher radiation exposure than traditional routine bidimensional examinations for orthodontic diagnosis, although low-dose protocols have markedly reduced radiation exposure over time. The objective of this preliminary feasibility study is to compare the accuracy and diagnostic capabilities of an already-validated three-dimensional Cephalometric Analysis on CBCT to those of an Analysis on 3-T magnetic resonance imaging (3T-MRI) to assess whether the latter can deliver a comparable quality of information while avoiding radiation exposure. MATERIALS AND METHODS: In order to test the feasibility of three-dimensional cephalometry on 3T-MRI, 18 subjects (4 male; 14 female) with mean age 37.8\u2009\ub1\u2009SD 10.2, who had undergone both maxillofacial CBCT and maxillofacial 3T-MRI for various purposes within 1 month, were selected from the archive of the Department of Dentistry and Maxillofacial Surgery of Fondazione Ospedale Policlinico Maggiore, IRCCS, Milano, Italy. A three-dimensional Cephalometric Analysis composed of ten midsagittal and four bilateral landmarks and 24 measurements (11 angular, 13 linear) was performed on both scans using Mimics Research\uae v. 17.0 (NV, Technologielaan 15, 3001 Leuven, Belgium). Cephalometric Analysis was performed twice by two independent orthodontists for each scan, and each orthodontist repeated the measurements 3 weeks later. Statistical Analysis was performed with SPSS\uae 20.00 for Windows (IBM\uae Corporation, Sommers, NY, USA). A Bland-Altman test for each Cephalometric value was performed to assess the agreement between the procedures. The intraclass correlation coefficient (ICC) was used to assess interobserver and intraobserver reliability. The coefficient of variation was used to evaluate precision. RESULTS: Both procedures showed good reliability, with mean intraobserver ICCs of 0.977/0.971 for CBCT and 0.881/0.912 for MRI. The average interobserver ICCs were 0.965 for CBCT and 0.833 for MRI. A Bland-Altman Analysis for the Cephalometric tracing revealed a similar range of agreement between the two modalities; the bias range (mean\u2009\ub1\u2009SD) was -\u20090.25-0.66\u2009mm (0.174\u2009\ub1\u20090.31) for distances and -\u20090.41-0.54\ub0 (0.12\u2009\ub1\u20090.33) for angles. CONCLUSIONS: Within the main limitation of this pilot study, that is, the small sample, it is possible to state that Cephalometric measurements on 3T-MRI seem to possess adequate reliability and repeatability and that they show satisfying agreement with values measured on CBCTs. An MRI examination does not expose patients to ionizing radiation and could provide an alternative to CBCT for three-dimensional Cephalometrics in the future