Consistency of 3D femoral torsion measurement from MRI compared to CT gold standard

Abstract Background Several hip and knee pathologies are associated with aberrant femoral torsion. Diagnostic workup includes computed tomography (CT) and magnetic resonance imaging (MRI). For three-dimensional (3D) analysis of complex deformities it would be desirable to measure femoral torsion from MRI data to avoid ionizing radiation of CT in a young patient population. 3D measurement of femoral torsion from MRI has not yet been compared to measurements from CT images. We hypothesize that agreement will exist between MRI and CT 3D measurements of femoral torsion. Methods CT and MRI data from 29 hips of 15 patients with routine diagnostic workup for suspected femoroacetabular impingement (FAI) were used to generate 3D bone models. 3D measurement of femoral torsion was performed by two independent readers using the method of Kim et al. which is validated for CT. Inter-modalitiy and inter-reader intraclass correlation coefficients (ICC) were calculated. Results Between MRI and CT 3D measurements an ICC of 0.950 (0.898; 0.976) (reader 1) respectively 0.950 (0.897; 0.976) (Reader 2) was found. The ICC (95% CI) expressing the inter-reader reliability for both modalities was 0.945 (0.886; 0.973) for MRI and 0.957 (0.910; 0.979) for CT, respectively. Mean difference between CT and MRI measurement was 0.42° (MRI – CT, SD: 2.77°, p = 0.253). Conclusions There was consistency between 3D measurements of femoral torsion between computer rendered MRI images compared to measurements with the “gold standard” of CT images. ICC for inter-modality and inter-reader consistency indicate excellent reliability. Accurate, reliable and reproducible 3D measurement of femoral torsion is possible from MRI images.

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High-Fidelity Anthropometric Facial Measurements Can Be Obtained From a Single Stereophotograph From the Vectra H1 3-Dimensional Camera

The Cleft Palate-Craniofacial Journal ◽

10.1177/1055665619839577 ◽

2019 ◽

Vol 56 (9) ◽

pp. 1164-1170 ◽

Cited By ~ 1

Author(s):

Diana S. Jodeh ◽

S. Alex Rottgers

Keyword(s):

Intraclass Correlation ◽

Three Dimensional ◽

Young Patients ◽

Correlation Coefficients ◽

Anthropometric Measurements ◽

3D Analysis ◽

Facial Morphology ◽

Anthropometric Measures ◽

3D Images ◽

3 Dimensional

Background: Anthropometry is a well-established means of measuring facial morphology. Although reliable, direct anthropometry can be time-consuming and not conducive to a busy clinical practice. The Vectra H1 handheld stereophotogrammetric system requires 3 stereophotographs taken from different perspectives to generate a three-dimensional (3D) surface. The time needed to take the 3 stereophotographs can increase the possibility of involuntary movements, precluding its use to assess young patients. To overcome this limitation, we evaluated if accurate linear facial measurements can be obtained from a single stereophotograph and compare these to the measurements taken by direct anthropometry. Methods: Twenty pediatric patients, aged 0 to 10 years, who were undergoing minor surgical procedures at Johns Hopkins All Children’s Hospital were recruited. Fourteen linear facial distances were obtained from each participant using direct anthropometry under general anesthesia. These same distances were measured using Mirror 3D analysis. Intraclass correlation was used to determine intrarater reliability on duplicate 3D images. Results: Correlation coefficients between 3D imaging in frontal view and direct anthropometric measurements were excellent for 13 measures taken, ranging from 0.8 (subnasale to columella and subnasale to stomion superius) to 0.98 (nasion to subnasale and subnasale to labiale superius). Correlation coefficients between submental view and direct anthropometric measurements were excellent for 13 measures as well, ranging from 0.77 (subnasale to columella) to 0.98 (nasion to subnasale). Conclusions: Linear anthropometric measurements taken from 3D surfaces generated from a single stereophotograph correlate closely with direct anthropometric measures. This improves workflow and applicability of anthropometric studies to our youngest patients.

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Two-dimensional versus three-dimensional Frӓnkel Manoeuvre: a reproducibility study

European Journal of Orthodontics ◽

10.1093/ejo/cjz081 ◽

2019 ◽

Vol 42 (2) ◽

pp. 157-162 ◽

Cited By ~ 3

Author(s):

Roberto Rongo ◽

Rosaria Bucci ◽

Raffaella Adaimo ◽

Massimo Amato ◽

Stefano Martina ◽

...

Keyword(s):

Gold Standard ◽

Three Dimensional ◽

Class Ii ◽

Observer Agreement ◽

3D Analysis ◽

Two Dimensional ◽

Skeletal Class ◽

Reproducibility Study ◽

Skeletal Class Ii ◽

3D Scans

Summary Background/Objectives To assess intra- and inter-observer reproducibility of the evaluation of the Frӓnkel Manoeuvre (FM) on three-dimensional (3D) scans and to compare it to the assessment on two-dimensional (2D) pictures. Materials/Methods This study included 44 individuals with a skeletal Class II malocclusion [9–16-years old mean age ± standard deviation: 13.5 ± 2.01 years]. All patients had a full Class II molar relationship, overjet ≥6 mm and point A, Nasion, point B angle (ANB) ≥5 degrees. During the FM, each patient was invited to bite in centric occlusion and then to posture the mandible forward to reach a Class I molar relationship. The FM was recorded both by a normal camera and a 3D scanner (3dMD system). Six examiners divided into two groups according to their orthodontic clinical experience (<5 and >10 years), and one gold standard in the evaluation of FM, commented twice (every 15 days) on both 2D photographs (T0 and T2) and 3D scans (T1 and T3). The intra-observer agreement and the inter-observer agreement compared to the gold standard were evaluated by computing the Cohen’s K. Results The agreement between observations for each examiner ranged from 0.36 to 1 on 2D pictures (T0 versus T2), and from 0.22 to 0.69 on 3D scans (T1 versus T3). The overall agreement was 0.63 (95 per cent CI = 0.35–0.91) in 2D analysis and 0.5 (95 per cent CI = 0.35–0.64) in 3D analysis. Conclusions/Implications The FM was less reproducible when performed on 3D records than on 2D pictures.

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Comparative study of glenoid version and inclination using two-dimensional images from computed tomography and three-dimensional reconstructed bone models

Clinics in Shoulder and Elbow ◽

10.5397/cise.2020.00220 ◽

2020 ◽

Vol 23 (3) ◽

pp. 119-124

Author(s):

Chang-Hyuk Choi ◽

Hee-Chan Kim ◽

Daewon Kang ◽

Jun-Young Kim

Keyword(s):

Computed Tomography ◽

Three Dimensional ◽

Ct Scans ◽

3D Measurement ◽

Two Dimensional ◽

Glenoid Version ◽

Observer Reliability ◽

3D Measurements ◽

Orthopedic Surgeons ◽

2D Images

Background: This study was performed to compare glenoid version and inclination measured using two-dimensional (2D) images from computed tomography (CT) scans or three-dimensional (3D) reconstructed bone models.Methods: Thirty patients who had undergone conventional CT scans were included. Two orthopedic surgeons measured glenoid version and inclination three times on 2D images from CT scans (2D measurement), and two other orthopedic surgeons performed the same measurements using 3D reconstructed bone models (3D measurement). The 3D-reconstructed bone models were acquired and measured with Mimics and 3-Matics (Materialise).Results: Mean glenoid version and inclination in 2D measurements were –1.705º and 9.08º, respectively, while those in 3D measurements were 2.635º and 7.23º. The intra-observer reliability in 2D measurements was 0.605 and 0.698, respectively, while that in 3D measurements was 0.883 and 0.892. The inter-observer reliability in 2D measurements was 0.456 and 0.374, respectively, while those in 3D measurements was 0.853 and 0.845.Conclusions: The difference between 2D and 3D measurements is not due to differences in image data but to the use of different tools. However, more consistent results were obtained in 3D measurement. Therefore, 3D measurement can be a good alternative for measuring glenoid version and inclination.

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Abstract 15534: Fully Automated "Hands-off" Evaluation of Left Atrial Volume in Children

Circulation ◽

10.1161/circ.142.suppl_3.15534 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Hunter Kauffman ◽

Kevin K Whitehead ◽

Michael Convery ◽

Matthew J O’Connor ◽

Michael Quartermain ◽

...

Keyword(s):

Clinical Practice ◽

Gold Standard ◽

Left Atrial ◽

Three Dimensional ◽

Left Atrial Volume ◽

Routine Clinical Practice ◽

3D Analysis ◽

Chamber Volume ◽

Volume Measurements ◽

Dimensional Echocardiography

Introduction: Three-dimensional echocardiography (3DE) has been shown to be superior to two-dimensional echocardiography (2DE) for the quantification of chamber volumes and dimensions. However, the utility of 3DE in routine clinical practice has been restricted by time-consuming analysis and the need for 3D-specific training. This study aims to assess the accuracy and clinical utility of Philips Dynamic Heart ModelA.I. (DHM), a “hands off” automated software program, that may be used to measure LA chamber dimensions. This is notable, as indexed LA volume has been used as a predictor of heart failure in adults. Hypothesis: We hypothesize that DHM will be able to quickly and accurately calculate left atrial chamber volume when compared to Cardiac MRI (CMRI) used as a gold standard. Methods: To date, 10 patients (Average Age 14.8±1.9) have undergone clinically indicated CMRI, immediately followed by 3DE, at the Children’s Hospital of Philadelphia. 3D images were analyzed via DHM without manual editing (hands-off approach). DHM automatically calculated maximum LA volume. LA volume was also calculated from CMRI images using the biplane method. LA volume measurements by DHM were correlated with CMRI. Results: DHM was able to calculate LA volume in an average time of 32±8 seconds, without additional human input. Furthermore, inter-technique correlations showed that LA volume measurements made via DHM correlated very well with LA volume measurements made via CMRI (R=0.85, p<0.005). (Figure 1) Conclusions: In children, fully automated evaluation of LA volume based on artificial intelligence is a viable alternative to time-consuming 3D analysis when compared to a CMRI gold standard. This method of “hands-off” analysis may prove to be useful in situations where trained 3D personnel are unavailable. Furthermore, the utilization of this method may result in a greater integration of 3D LA volume into routine clinical practice.

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A semi-automatic approach for longitudinal 3D upper airway analysis using voxel based registration

Dentomaxillofacial Radiology ◽

10.1259/dmfr.20210253 ◽

2021 ◽

Author(s):

Alexandru Diaconu ◽

Michael Boelstoft Holte ◽

Paolo Maria Cattaneo ◽

Else Marie Pinholt

Keyword(s):

Intraclass Correlation ◽

Three Dimensional ◽

Upper Airway ◽

Observer Agreement ◽

3D Analysis ◽

Anatomic Landmarks ◽

Cross Sectional ◽

Method Error ◽

Anterior Cranial Base ◽

Intraclass Correlations

Objectives: To propose and validate a reliable semi-automatic approach for three-dimensional (3D) analysis of the upper airway (UA) based on voxel-based registration (VBR). Methods: Post-operative cone beam computed tomography (CBCT) scans of ten orthognathic surgery patients were superimposed to the pre-operative CBCT scans by VBR using the anterior cranial base as reference. Anatomic landmarks were used to automatically cut the UA and calculate volumes and cross-sectional areas (CSA). The 3D analysis was performed by two observers twice, at an interval of two weeks. Intraclass correlations and Bland-Altman plots were used to quantify the measurement error and reliability of the method. The relative Dahlberg error was calculated and compared with a similar method based on landmark re-identification and manual measurements. Results: Intraclass correlation coefficient (ICC) showed excellent intra- and inter observer reliability (ICC ≥0.995). Bland-Altman plots showed good observer agreement, low bias and no systematic errors. The relative Dahlberg error ranged between 0.51–4.30% for volume and 0.24–2.90% for CSA. This was lower when compared with a similar, manual method. Voxel-based registration introduced 0.05–1.44% method error. Conclusions: The proposed method is shown to have excellent reliability and high observer agreement. The method is feasible for longitudinal clinical trials on large cohorts due to being semi-automatic.

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RELIABILITY AND VALIDITY STUDY OF A MEASUREMENT METHOD FOR THE GLENOID VERSION BY A 3-DIMENSIONAL BONE MODEL FROM 3.0 TESLA MRI

Journal of Musculoskeletal Research ◽

10.1142/s0218957716500123 ◽

2016 ◽

Vol 19 (03) ◽

pp. 1650012 ◽

Cited By ~ 1

Author(s):

Yohei Kanno ◽

Hajime Toda ◽

Tsutomu Horiuchi ◽

Katsuaki Nagai ◽

Masaki Katayose

Keyword(s):

Intraclass Correlation ◽

Reliability And Validity ◽

Ct Images ◽

Imaging Method ◽

3D Ct ◽

3D Mri ◽

Glenoid Version ◽

Bone Model ◽

3 Dimensional ◽

Ct And Mri

Objective: The authors investigated reliability and validity of 3D-MRI bone model of scapula by comparing the Glenoid versions that were measured each in 3D-CT images and 3D-MRI images. Materials and Methods: The scapula extraction DICOM data of MRI and CT was made to extract only a scapular domain. The scapula bone model was made with the scapula extraction DICOM data of MRI and CT. Glenoid version was measured on the scapula bone model. The mean and standard deviation of the Glenoid version was calculated by each imaging method (CT and MRI). Intraclass reliability of each imaging method (CT and MRI) and agreement between the two methods were evaluated. This was accomplished by calculating two separate measures of agreement: the intraclass correlation coefficient (ICC) and the Bland–Altman analysis. Results: Glenoid version measured from the 3D-CT images averaged [Formula: see text]0.679[Formula: see text][Formula: see text][Formula: see text]3.797, with an ICC of 0.975. Glenoid version measured from the 3D-MRI images averaged [Formula: see text]0.801[Formula: see text][Formula: see text][Formula: see text]3.682, with an ICC of 0.980. Conclusions: 3D-MRI bone model of scapula evaluated the reliability and the validity. 3D-MRI bone model of scapula was found to measure like 3D-CT bone model of scapula.

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The Reliability of Two- and Three-Dimensional Cephalometric Measurements: A CBCT Study

Diagnostics ◽

10.3390/diagnostics11122292 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2292

Author(s):

Chenshuang Li ◽

Hellen Teixeira ◽

Nipul Tanna ◽

Zhong Zheng ◽

Stephanie Hsiang Yi Chen ◽

...

Keyword(s):

Intraclass Correlation ◽

Three Dimensional ◽

Young Patients ◽

Correlation Coefficients ◽

3D Analysis ◽

Intraclass Correlation Coefficients ◽

Lateral Cephalograms ◽

Adults And Children ◽

Left And Right ◽

Cephalometric Measurements

Cephalometry is a standard diagnostic tool in orthodontic and orthognathic surgery fields. However, built-in magnification from the cephalometric machine produces double images from left- and right-side craniofacial structures on the film, which poses difficulty for accurate cephalometric tracing and measurements. The cone-beam computed tomography (CBCT) images not only allow three-dimensional (3D) analysis, but also enable the extraction of two-dimensional (2D) images without magnification. To evaluate the most reliable cephalometric analysis method, we extracted 2D lateral cephalometric images with and without magnification from twenty full-cranium CBCT datasets; images were extracted with magnification to mimic traditional lateral cephalograms. Cephalometric tracings were performed on the two types of extracted 2D lateral cephalograms and on the reconstructed 3D full cranium images by two examiners. The intra- and inter-examiner intraclass correlation coefficients (ICC) were compared between linear and angular parameters, as well as between CBCT datasets of adults and children. Our results showed that overall, tracing on 2D cephalometric images without magnification increased intra- and inter-examiner reliability, while 3D tracing reduced inter-examiner reliability. Angular parameters and children’s images had the lowest inter- and intra-examiner ICCs compared with adult samples and linear parameters. In summary, using lateral cephalograms extracted from CBCT without magnification for tracing/analysis increased reliability. Special attention is needed when analyzing young patients’ images and measuring angular parameters.

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A 3D Measurement Method Based on Three Frequencies PSP

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.701-702.471 ◽

2014 ◽

Vol 701-702 ◽

pp. 471-474

Author(s):

Li Mei Song ◽

Guang Xin Xing ◽

Peng Qiang Wang ◽

Jiang Tao Xi ◽

Qing Hua Guo

Keyword(s):

3D Reconstruction ◽

Precision Measurement ◽

Measurement Method ◽

Three Dimensional ◽

Trigonometric Function ◽

Phase Unwrapping ◽

Optical Information ◽

3D Measurement ◽

High Precision Measurement ◽

3D Measurements

This paper proposes a method of global phase unwrapping used in multi-frequency three-dimensional (3D) measurements. In this method, three kinds of optical information which change in accordance with trigonometric function (sine or cosine) to the objects. The optical information cycles is P1, P2 and P3. Each waveform should 4-8 steps phase shifts. Then, calculate the phase value of each cycle. The composited phase value of two cycles and the final composited phase value of three cycles are calculated by image shift of each cycle. Finally, calculate the global phase value of each cycle based on the composited phase, thus, all the 3D coordinates of objects can be obtain after 3D reconstruction. The proposed method can solves the object surfaces color changing largely in 3D measurements. This method realizes high precision measurement without spray developer and achieves the protection of the environment.

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A new segmentation algorithm for measuring CBCT images of nasal airway: a pilot study

PeerJ ◽

10.7717/peerj.6246 ◽

2019 ◽

Vol 7 ◽

pp. e6246 ◽

Cited By ~ 2

Author(s):

Chen Zhang ◽

Robin Bruggink ◽

Frank Baan ◽

Ewald Bronkhorst ◽

Thomas Maal ◽

...

Keyword(s):

Gold Standard ◽

Intraclass Correlation ◽

Three Dimensional ◽

Correlation Coefficients ◽

Nasal Airway ◽

Intraclass Correlation Coefficients ◽

Shell Models ◽

3D Printed ◽

Software Programs ◽

Equivalent Method

Background Three-dimensional (3D) modeling of the nasal airway space is becoming increasingly important for assessment in breathing disorders. Processing cone beam computed tomography (CBCT) scans of this region is complicated, however, by the intricate anatomy of the sinuses compared to the simpler nasopharynx. A gold standard for these measures also is lacking. Previous work has shown that software programs can vary in accuracy and reproducibility outcomes of these measurements. This study reports the reproducibility and accuracy of an algorithm, airway segmentor (AS), designed for nasal airway space analysis using a 3D printed anthropomorphic nasal airway model. Methods To test reproducibility, two examiners independently used AS to edit and segment 10 nasal airway CBCT scans. The intra- and inter-examiner reproducibility of the nasal airway volume was evaluated using paired t-tests and intraclass correlation coefficients. For accuracy testing, the CBCT data for pairs of nasal cavities were 3D printed to form hollow shell models. The water-equivalent method was used to calculate the inner volume as the gold standard, and the models were then embedded into a dry human skull as a phantom and subjected to CBCT. AS, along with the software programs MIMICS 19.0 and INVIVO 5, was applied to calculate the inner volume of the models from the CBCT scan of the phantom. The accuracy was reported as a percentage of the gold standard. Results The intra-examiner reproducibility was high, and the inter-examiner reproducibility was clinically acceptable. AS and MIMICS presented accurate volume calculations, while INVIVO 5 significantly overestimated the mockup of the nasal airway volume. Conclusion With the aid of a 3D printing technique, the new algorithm AS was found to be a clinically reliable and accurate tool for the segmentation and reconstruction of the nasal airway space.

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A deep learning method for automatic segmentation of the bony orbit in MRI and CT images

Scientific Reports ◽

10.1038/s41598-021-93227-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jared Hamwood ◽

Beat Schmutz ◽

Michael J. Collins ◽

Mark C. Allenby ◽

David Alonso-Caneiro

Keyword(s):

Deep Learning ◽

Human Performance ◽

Automatic Segmentation ◽

Ct Images ◽

Human Observer ◽

In Series ◽

Magnetic Resonance Imaging Mri ◽

High Degree ◽

Orbital Region ◽

Ct And Mri

AbstractThis paper proposes a fully automatic method to segment the inner boundary of the bony orbit in two different image modalities: magnetic resonance imaging (MRI) and computed tomography (CT). The method, based on a deep learning architecture, uses two fully convolutional neural networks in series followed by a graph-search method to generate a boundary for the orbit. When compared to human performance for segmentation of both CT and MRI data, the proposed method achieves high Dice coefficients on both orbit and background, with scores of 0.813 and 0.975 in CT images and 0.930 and 0.995 in MRI images, showing a high degree of agreement with a manual segmentation by a human expert. Given the volumetric characteristics of these imaging modalities and the complexity and time-consuming nature of the segmentation of the orbital region in the human skull, it is often impractical to manually segment these images. Thus, the proposed method provides a valid clinical and research tool that performs similarly to the human observer.

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