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Validity and reliability of masseter muscles segmentation from the transverse sections of Cone-Beam CT scans compared with MRI scans

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INTERNATIONAL JOURNAL OF computer assisted RADIOLOGY AND SURGERY 2022年第4期17卷 751-759页

作者： Pan, Yichen Wang, Yinghui Li, Gang Chen, Si Xu, Tianmin Peking Univ Sch & Hosp Stomatol Dept Orthodont 22 Zhongguancun Ave South Beijing 100081 Peoples R China Natl Engn Lab Digital & Mat Technol Stomatol 22 Zhongguancun Ave South Beijing 100081 Peoples R China Beijing Key Lab Digital Stomatol 22 Zhongguancun Ave South Beijing 100081 Peoples R China Peking Univ Sch & Hosp Stomatol Dept Oral & Maxillofacial Radiol 22 Zhongguancun Ave South Beijing 100081 Peoples R China

Background To evaluate the validity and reliability of cone-beam computed tomography (CBCT) masseter muscle segmentation by comparing with the magnetic resonance imaging (MRI) masseter muscle segmentation of the same patients. Methods Seventeen volunteers were included in this study. CBCT and MRI scans of the volunteers were taken, respectively, within one month. The masseter muscles in the CBCT scans were segmented by a generative adversarial network (GAN)-based framework combined with manual check. The masseter muscles in the MRI scans were segmented manually. The segmentations were repeated by the first examiner and a second examiner. For cross-sectional area (CSA), paired t-test, intraclass correlation coefficient (ICC) and standard error of measurement (SEM) were calculated to evaluate the validity and reliability of the segmentations. The validity and reliability were also calculated by Dice similarity coefficient (DSC) and average Hausdorff distance (aHD) between different segmentations. Seventeen volunteers were included in this study. CBCT and MRI scans of the volunteers were taken, respectively, within one month. The masseter muscles in the CBCT scans were segmented by a generative adversarial network (GAN)-based framework combined with manual check. The masseter muscles in the MRI scans were segmented manually. The segmentations were repeated by the first examiner and a second examiner. For cross-sectional area (CSA), paired t-test, intraclass correlation coefficient (ICC) and standard error of measurement (SEM) were calculated to evaluate the validity and reliability of the segmentations. The validity and reliability were also calculated by Dice similarity coefficient (DSC) and average Hausdorff distance (aHD) between different segmentations. Results Paired t-test showed that there was no significant difference in CSA between CBCT and MRI masseter segmentations. The ICCs were all larger than 0.95 and the SEM was less than 4.85 mm(2) for CSA. The DSC was

关键词： Cone-beam computed tomography Magnetic resonance imaging Masseter muscle computer-assisted image processing Reliability and validity

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Automatic quantification of myocardium and pericardial fat from coronary computed tomography angiography: a multicenter study

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EUROPEAN RADIOLOGY 2021年第6期31卷 3826-3836页

作者： He, Xiuxiu Guo, Bang Jun Lei, Yang Wang, Tonghe Curran, Walter J. Liu, Tian Zhang, Long Jiang Yang, Xiaofeng Emory Univ Dept Radiat Oncol Atlanta GA 30322 USA Emory Univ Winship Canc Inst Atlanta GA 30322 USA Nanjing Univ Affiliated Jinling Hosp Med Sch Dept Diagnost Radiol Nanjing 210002 Peoples R China

ObjectivesTo develop a deep learning-based method for simultaneous myocardium and pericardial fat quantification from coronary computed tomography angiography (CCTA) for the diagnosis and treatment of cardiovascular disease (CVD).MethodsWe retrospectively identified CCTA data obtained between May 2008 and July 2018 in a multicenter (six centers) CVD study. The proposed method was evaluated on 422 patients' data by two studies. The first overall study involves training model on CVD patients and testing on non-CVD patients, as well as training on non-CVD patients and testing on CVD patients. The second study was performed using the leave-center-out approach. The method performance was evaluated using Dice similarity coefficient (DSC), Jaccard index (JAC), 95% Hausdorff distance (HD95), mean surface distance (MSD), residual mean square distance (RMSD), and the center of mass distance (CMD). The robustness of the proposed method was tested using the nonparametric Kruskal-Wallis test and post hoc test to assess the equality of distribution of DSC values among different *** automatic segmentation achieved a strong correlation with contour (ICC and R>0.97, p value <0.001 throughout all tests). The accuracy of the proposed method remained high through all the tests, with the median DSC higher than 0.88 for pericardial fat and 0.96 for myocardium. The proposed method also resulted in mean MSD, RMSD, HD95, and CMD of less than 1.36 mm for pericardial fat and 1.00 mm for *** proposed deep learning-based segmentation method enables accurate simultaneous quantification of myocardium and pericardial fat in a multicenter *** Points Deep learning-based myocardium and pericardial fat segmentation method tested on 422 patients' coronary computed tomography angiography in a multicenter *** dot The proposed method provides segmentations with high volumetric accuracy (ICC and R>0.97, p value <0.001) and similar shape as manual an

关键词： Deep learning computer-assisted image processing Cardiovascular disease Computed tomography angiography

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Optimal threshold of subtraction method for quantification of air-trapping on coregistered CT in COPD patients

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EUROPEAN RADIOLOGY 2016年第7期26卷 2184-2192页

作者： Lee, Sang Min Seo, Joon Beom Lee, Sang Min Kim, Namkug Oh, Sang Young Oh, Yeon-Mok Univ Ulsan Coll Med Asan Med Ctr Dept Radiol 88 Olymp Ro 43 Gil Seoul 138736 South Korea Univ Ulsan Coll Med Asan Med Ctr Res Inst Radiol 88 Olymp Ro 43 Gil Seoul 138736 South Korea Univ Ulsan Coll Med Asan Med Ctr Dept Pulm & Crit Care Med 88 Olymp Ro 43 Gil Seoul 138736 South Korea Univ Ulsan Coll Med Asan Med Ctr Clin Res Ctr Chron Obstruct Airway Dis 88 Olymp Ro 43 Gil Seoul 138736 South Korea

To investigate the optimal threshold of subtraction method for quantification of air trapping on co-registered CT in COPD patients in correlation with pulmonary function parameters. From June 2005 to October 2010, 174 patients were included in our study. Inspiration and expiration CT were performed followed by non-rigid registration using in-house software. The subtraction value per voxel between inspiration and registered expiration CT was obtained, and volume fraction of air trapping (air trapping index, ATI), using variable thresholds was calculated. ATI, expiration/inspiration ratio of mean lung density (E/I MLD) and the percentage of lung voxels below -856 HU on expiration CT (Exp(-856)) were correlated with FEF25-75% and RV/TLC. The highest correlation coefficient with FEF25-75% was -0.656, using the threshold of 80 HU. As for RV/TLC, the highest correlation coefficient was 0.664, using the threshold of 30 HU. When plotting the relationship between subtraction thresholds and FEF25-75% and RV/TLC, the threshold of 60 HU was most suitable (r = -0.649 and 0.651). Those correlation coefficients were comparable to the results with E/I MLD (r = -0.670 and 0.657) and Exp(-856) (r = -0.604 and 0.565). The optimal threshold for quantification of air trapping was 60 HU and showed comparable correlations with pulmonary function parameters. aEuro cent The optimal CT threshold of subtraction method for air trapping was 60 HU. aEuro cent ATI with 60 HU threshold was comparable to E/I MLD and Exp (-856) . aEuro cent Emphysema may substantially contribute to air trapping with statistical significance (P < 0.001).

关键词： Chronic obstructive pulmonary disease Airway obstruction Computed tomography computer-assisted image processing Pulmonary function test

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Fully automated software to monitor wear in prosthetic knees using fluoroscopic images

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EUROPEAN RADIOLOGY 2001年第11期11卷 2184-2187页

作者： Duryea, J Grainger, AJ Hide, IG Genant, HK Campbell, RSD Univ Calif San Francisco Dept Radiol Osteoporosis & Arthrit Res Grp San Francisco CA 94143 USA Univ Teesside S Cleveland Hosp Dept Radiol Middlesbrough TS4 3BW Cleveland England Univ Teesside Ctr Hlth & Med Res Middlesbrough TS4 3BW Cleveland England

Total knee arthroplasty is now a widely accepted treatment for late-stage arthritis. Wear of the polyethylene layer in prosthetic knees is a known cause of implant failure. Early detection of wear may allow prediction of device failure. In this paper we describe a fully automated image processing algorithm to measure the minimum tibiofemoral joint space width (mJSW) for monitoring prosthesis wear radiographically. The femoral portion and tibial plate were automatically delineated and mJSW was calculated in each compartment. The software also delineated the tip of the prosthesis pin in order to make a magnification correction. The algorithm was tested with a set of triplicate acquisitions of 18 fluoroscopic knee images. The RMS standard deviation (RMSSD) for the triplicate measurements was calculated as a figure of merit. The RMSSD was 0.077 and 0.087 mm for the lateral and medial compartments. The computer successfully found the minimum JSW for both compartments in all 54 images. A single case (2% of total) required user interaction to correct for an obvious failure to delineate the prosthesis pin. We document a robust and precise tool for quantifying mJSW to monitor prosthesis wear.

关键词： computer-assisted image processing knee joint prosthesis knee replacement

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CLINICAL ANATOMY 2014年第3期27卷 360-364页

作者： Seo, Jae-Hyun Hwang, Se-Hwan Kang, Jun-Myung Kim, Chung-Soo Joo, Young-Hoon Catholic Univ Korea Coll Med Dept Otolaryngol Head & Neck Surg Puchon 420717 Kyounggi Do South Korea

The purpose of this study was to establish normative data of laryngotracheal dimensions and shape and to evaluate differences associated with age and sex using three-dimensional (3D) imaging. A total of 120 patients (64 boys and 56 girls) were included. Subjects were divided into four groups: Group 1 (0-2 years), Group 2 (3-7 years), Group 3 (8-13 years), and Group 4 (14-20 years). Using 3D image processing software, the laryngeal volume (LV), tracheal volume (TV), anteroposterior diameter at the glottis, cross-sectional area (CSA) at the subglottis, and laryngeal angle (LA) of the thyroid laminae were measured. Parameters of laryngotracheal volume and size were positively correlated with age, whereas the LA was inversely correlated with age. The LV, TV, CSA-3 mm, and CSA-5 mm exhibited a growth spurt in Groups 2 and 3. The LA decreased at a faster rate in Group 1 (P = 0.012). In Groups 1 and 2, there were no differences between genders for each laryngotracheal segmentation or plane. However, gender differences in the TV of Group 3 were statistically significant (P = 0.030). In Group 4, gender differences of all airway parameters were evident. Volume and other dimensions of the laryngotracheal airway increase with age. There was a significant increase in the LV, TV, CSA-3 mm, and CSA-5 mm in Groups 2 and 3. The LA correlated negatively with age in the Group 1. Significant sex dimorphisms are evident in Group 4. Clin. Anat. 27:360-364, 2014. (c) 2013 Wiley Periodicals, Inc.

关键词： child organ size trachea larynx computer-assisted image processing

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Different therapeutic mechanisms of rigid and semi-rigid mandibular repositioning devices in obstructive sleep apnea syndrome

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JOURNAL OF CRANIO-MAXILLOFACIAL SURGERY 2014年第8期42卷 1650-1654页

作者： Suga, Hokuto Mishima, Katsuaki Nakano, Hiroyuki Nakano, Asuka Matsumura, Mayumi Mano, Takamitsu Yamasaki, Youichi Ueyama, Yoshiya Kagoshima Univ Grad Sch Med & Dent Sci Dept Pediat Dent Kagoshima 8908544 Japan Yamaguchi Univ Grad Sch Med Dept Oral & Maxillofacial Surg Ube Yamaguchi 7558505 Japan Kyushu Univ Grad Sch Dent Dept Oral & Maxillofacial Surg 2 Higashi Ku Fukuoka 8128585 Japan

To clarify the mechanisms of rigid and semi-rigid mandibular repositioning devices (MRDs) in obstructive sleep apnea syndrome (OSAS), seven and 13 patients received rigid and semi-rigid MRDs, respectively. Each patient underwent polysomnographic and computed tomographic examinations at the initial consultation and after symptom improvement. Three-dimensional models of the upper airway (hard palate level to epiglottic base) were reconstructed by image processing software (Mimics version 14.2) to measure airway morphology. The mean age and body mass index were 58.1 years and 24.8 kg/m(2), respectively, in the rigid MRD group and 57.9 years and 23.2 kg/m(2), respectively, in the semi-rigid MRD group. The apnea-hypopnea index significantly improved (P < 0.05, Wilcoxon signed-rank test) from 22.0 to 8.9 and 20.5 to 11.5 events per hour of sleep in the respective groups. The cross-sectional areas measured at the epiglottic tip (from 2.0 to 2.6 cm(2)) and hard palate (from 2.6 to 3.3 cm(2)) levels also increased in the respective groups (P < 0.05). However, airway volume, cross-sectional area measured at the uvular tip level, and anteroposterior and transverse diameters of the airway were not significantly different. In conclusion, both types of MRDs improve respiratory status, but they affect different parts of the airway. (C) 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

关键词： computer-assisted image processing Computed tomography Mandibular repositioning device Polysomnography Sleep apnea syndromes Temporomandibular joint disorders

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New technology in dietary assessment: a review of digital methods in improving food record accuracy

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PROCEEDINGS OF THE NUTRITION SOCIETY 2013年第1期72卷 70-76页

作者： Stumbo, Phyllis J. Univ Iowa Inst Clin & Translat Sci Iowa City IA 52242 USA

Methods for conducting dietary assessment in the United States date back to the early twentieth century. Methods of assessment encompassed dietary records, written and spoken dietary recalls, FFQ using pencil and paper and more recently computer and internet applications. Emerging innovations involve camera and mobile telephone technology to capture food and meal images. This paper describes six projects sponsored by the United States National Institutes of Health that use digital methods to improve food records and two mobile phone applications using crowdsourcing. The techniques under development show promise for improving accuracy of food records.

关键词： Dietary assessment Dietary record Mobile telephone computer-assisted image processing Epidemiological methods

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EFFECT OF CHRONIC RESPIRATORY LOAD ON CYTOCHROME-OXIDASE ACTIVITY IN DIAPHRAGMATIC FIBERS

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JOURNAL OF APPLIED PHYSIOLOGY 1992年第1期72卷 266-271页

作者： BAZZY, AR KIM, YJ Department of Pediatrics Yale University School of Medicine New Haven Connecticut 06510.

To determine whether the increase in oxidative capacity after respiratory muscle training with chronic inspiratory loads in sheep is specific to a particular fiber type, we measured cytochrome c oxidase (COX) activity in type I and type II fibers. COX activity in individual fibers was examined histochemically and measured as relative optical density by use of an image processing system. Fiber types were differentiated by the myosin adenosine-triphosphatase reaction. We found that COX activity was higher in both fiber types in the trained diaphragms than in the control diaphragms (P < 0.01). The increase with training was greater in type II (39%) than in type I fibers (21%), resulting in relatively homogeneous COX activity in all diaphragmatic fibers. The proportion of type I fibers increased from 43.4 +/- 5.4% in the control diaphragm to 53.1 +/- 2.9% in the trained diaphragm, whereas the proportion of type II fibers decreased (P < 0.001). We conclude that respiratory muscle training activates oxidative enzyme activity in both diaphragmatic fiber types;this activation is differentially more in type II fibers, which also decrease in proportion, and less in type I fibers, which increase in proportion.

关键词： RESPIRATORY MUSCLE TRAINING FIBER TYPE computer-assisted image processing

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Aktuelle MRT-Bildgebung des Knorpels im Kontext der Gonarthrose (Teil 1): Grundlagen und Sequenzen

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RADIOLOGIE 2024年第4期64卷 295-303页

作者： Lemainque, Teresa Huppertz, Marc Sebastian Yueksel, Can Siepmann, Robert Kuhl, Christiane Roemer, Frank Truhn, Daniel Nebelung, Sven Univ Klinikum Aachen Klin Diagnost & Intervent Radiol Pauwelsstr 30 D-52074 Aachen Germany Univ Klinikum Erlangen Radiol Inst Erlangen Germany Friedrich Alexander Univ Erlangen Nurnberg Erlangen Germany Boston Univ Chobanian & Avedisian Sch Med Dept Radiol Boston MA USA

Magnetic resonance imaging (MRI) is the clinical method of choice for cartilage imaging in the context of degenerative and nondegenerative joint diseases. The MRI-based definitions of osteoarthritis rely on the detection of osteophytes, cartilage pathologies, bone marrow edema and meniscal lesions but currently a scientific consensus is lacking. In the clinical routine proton density-weighted, fat-suppressed 2D turbo spin echo sequences with echo times of 30-40 ms are predominantly used, which are sufficiently sensitive and specific for the assessment of cartilage. The additionally acquired T1-weighted sequences are primarily used for evaluating other intra-articular and periarticular structures. Diagnostically relevant artifacts include magic angle and chemical shift artifacts, which can lead to artificial signal enhancement in cartilage or incorrect representations of the subchondral lamina and its thickness. Although scientifically validated, high-resolution 3D gradient echo sequences (for cartilage segmentation) and compositional MR sequences (for quantification of physical tissue parameters) are currently reserved for scientific research questions. The future integration of artificial intelligence techniques in areas such as image reconstruction (to reduce scan times while maintaining image quality), image analysis (for automated identification of cartilage defects), and image postprocessing (for automated segmentation of cartilage in terms of volume and thickness) will significantly improve the diagnostic workflow and advance the field further.

关键词： Magnetic resonance imaging Joint cartilage Osteoarthritis computer-assisted image processing Artificial intelligence

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Liver segmental volume and attenuation ratio (LSVAR) on portal venous CT scans improves the detection of clinically significant liver fibrosis compared to liver segmental volume ratio (LSVR)

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ABDOMINAL RADIOLOGY 2021年第5期46卷 1912-1921页

作者： Obmann, V. C. Marx, C. Hrycyk, J. Berzigotti, A. Ebner, L. Mertineit, N. Grani, Ch. Heverhagen, J. T. Christe, A. Huber, A. T. Univ Bern Bern Univ Hosp Inselspital Dept Diagnost Intervent & Pediat Radiol Freiburgstr 10 CH-3010 Bern Switzerland Univ Bern Bern Univ Hosp Hepatol Dept Visceral Surg & MedHepatol Bern Switzerland Univ Bern Bern Univ Hosp Inselspital Dept Cardiol Bern Switzerland

Background The aim of this proof-of-concept study was to show that the liver segmental volume and attenuation ratio (LSVAR) improves the detection of significant liver fibrosis on portal venous CT scans by adding the liver vein to cava attenuation (LVCA) to the liver segmental volume ratio (LSVR). Material and methods Patients who underwent portal venous phase abdominal CT scans and MR elastography (reference standard) within 3 months between 02/2016 and 05/2017 were included. The LSVAR was calculated on portal venous CT scans as LSVR*LVCA, while the LSVR represented the volume ratio between Couinaud segments I-III and IV-VIII, and the LVCA represented the density of the liver veins compared to the density in the vena cava. The LSVAR and LSVR were compared between patients with and without significantly elevated liver stiffness (based on a cutoff value of 3.5 kPa) using the Mann-Whitney U test and ROC curve analysis. Results The LSVR and LSVAR allowed significant differentiation between patients with (n = 19) and without (n = 122) significantly elevated liver stiffness (p < 0.001). However, the LSVAR showed a higher area under the curve (AUC = 0.96) than the LSVR (AUC = 0.74). The optimal cutoff value was 0.34 for the LSVR, which detected clinically increased liver stiffness with a sensitivity of 53% and a specificity of 88%. With a cutoff value of 0.67 for the LSVAR, the sensitivity increased to 95% while maintaining a specificity of 89%. Conclusion The LSVAR improves the detection of significant liver fibrosis on portal venous CT scans compared to the LSVR.

关键词： Computed tomography Liver cirrhosis Fibrosis computer-assisted image processing computer-assisted diagnosis

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