scholarly journals Accurate Segmentation of the Left Ventricle in Computed Tomography Images for Local Wall Thickness Assessment

2010 ◽  
pp. 400-408 ◽  
Author(s):  
J. Peters ◽  
J. Lessick ◽  
R. Kneser ◽  
I. Wächter ◽  
M. Vembar ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Left Ventricle ◽  
Wall Thickness ◽  
Computed Tomography Images

scholarly journals POS0340 VASCULAR IMAGING IN PATIENTS WITH REFRACTORY TAKAYASU ARTERITIS TREATED WITH TOCILIZUMAB: ANALYSIS FROM A RANDOMIZED CONTROLLED TRIAL

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 398.1-398
Author(s):  
Y. Nakaoka ◽  
M. Yanagawa ◽  
A. Hata ◽  
K. Yamashita ◽  
N. Okada ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Randomized Controlled Trial ◽  
Wall Thickness ◽  
Takayasu Arteritis ◽  
Controlled Trial ◽  
Vascular Imaging ◽  
Research Support ◽  
Chugai Pharmaceutical ◽  
Randomized Controlled ◽  
Computed Tomography Images

Background:In the TAKT study, a randomized controlled trial of tocilizumab (TCZ) in patients with refractory Takayasu arteritis (TAK) in Japan, the primary end point of time to relapse after induction of remission with glucocorticoid (GC) treatment showed a trend favoring TCZ over placebo (hazard ratio 0.41 [95.41% confidence interval, 0.15-1.10; p=0.0596]),1 but the double-blind period was too short for imaging evaluation.Objectives:To independently evaluate vascular imaging in a post hoc analysis of radiographs from the TAKT study.Methods:Computed tomography images from patients in the TAKT study were evaluated by three independent radiologists who were not involved in the original trial. Patients who received TCZ and had computed tomography images available (n=28) were included. Assessments were made in 22 arteries for the change from baseline in wall thickness (primary end point), dilatation/aneurysm, stenosis/occlusion, or wall enhancement for at least 96 weeks after the start of tocilizumab treatment. Patient-level assessments were also conducted.Results:Among 28 patients who received at least one dose of TCZ and for whom images were available, 86.7% of 22 arteries had improved/stable (no progression) wall thickness at week 96. The proportions of patients with no progressed, partially progressed, or newly progressed lesions were 57.1%, 10.7%, and 28.6% for wall thickness, and the proportions without progressed lesions were 92.9% for dilatation/aneurysm and 85.7% for stenosis/occlusion (Figure 1). Patients with newly progressed lesions, reflecting more refractory disease, were receiving glucocorticoid doses that could not be reduced below 0.1 mg/kg/day at week 96.Conclusion:Approximately 60% of patients with TAK treated with tocilizumab did not experience progression in wall thickness. Few patients experienced progressive dilatation/aneurysm or stenosis/occlusion. Wall thickness progression likely resulted from refractory TAK. Patients who experience this should be monitored regularly by imaging, and additional glucocorticoid or immunosuppressive treatment should be considered to avoid vascular progression.References:[1]Nakaoka Y et al. Ann Rheum Dis. 2018;77:348-354.Disclosure of Interests:Yoshikazu Nakaoka Consultant of: Roche/Genentech, Grant/research support from: Roche/Genentech, Masahiro Yanagawa Consultant of: Roche/Genentech, Akinori Hata Consultant of: Roche/Genentech, Katsuhisa Yamashita Employee of: Chugai Pharmaceutical Co., Ltd., Norihiro Okada Employee of: Chugai Pharmaceutical Co., Ltd., Shinji Yamakido Employee of: Chugai Pharmaceutical Co., Ltd., Hiromitsu Hayashi Consultant of: Roche/Genentech, David Jayne Consultant of: Roche/Genentech, Grant/research support from: Roche/Genentech

scholarly journals Quantitative computed tomography analysis of the airways in patients with cystic fibrosis using automated software: correlation with spirometry in the evaluation of severity

2016 ◽  
Vol 49 (6) ◽  
pp. 351-357 ◽  
Author(s):  
Marcel Koenigkam Santos ◽  
Danilo Lemos Cruvinel ◽  
Marcelo Bezerra de Menezes ◽  
Sara Reis Teixeira ◽  
Elcio de Oliveira Vianna ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Cystic Fibrosis ◽  
Quantitative Analysis ◽  
Wall Thickness ◽  
Quantitative Computed Tomography ◽  
Airflow Obstruction ◽  
Computed Tomography Images ◽  
Group I ◽  
Group Ii ◽  
Automated Software

Abstract Objective: To perform a quantitative analysis of the airways using automated software, in computed tomography images of patients with cystic fibrosis, correlating the results with spirometric findings. Materials and Methods: Thirty-four patients with cystic fibrosis were studied-20 males and 14 females; mean age 18 ± 9 years-divided into two groups according to the spirometry findings: group I (n = 21), without severe airflow obstruction (forced expiratory volume in first second [FEV1] > 50% predicted), and group II (n = 13), with severe obstruction (FEV1 ≤ 50% predicted). The following tracheobronchial tree parameters were obtained automatically: bronchial diameter, area, thickness, and wall attenuation. Results: On average, 52 bronchi per patient were studied. The number of bronchi analyzed was higher in group II. The correlation with spirometry findings, especially between the relative wall thickness of third to eighth bronchial generation and predicted FEV1, was better in group I. Conclusion: Quantitative analysis of the airways by computed tomography can be useful for assessing disease severity in cystic fibrosis patients. In patients with severe airflow obstruction, the number of bronchi studied by the method is higher, indicating more bronchiectasis. In patients without severe obstruction, the relative bronchial wall thickness showed a good correlation with the predicted FEV1.

scholarly journals Hyperparameter optimisation and validation of registration algorithms for measuring regional ventricular deformation using retrospective gated computed tomography images

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Orod Razeghi ◽  
Mattias Heinrich ◽  
Thomas E. Fastl ◽  
Cesare Corrado ◽  
Rashed Karim ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Left Ventricle ◽  
Open Source ◽  
Cardiac Computed Tomography ◽  
Cardiac Mechanics ◽  
Left Ventricular ◽  
Anatomical Landmarks ◽  
Observer Error ◽  
Computed Tomography Images ◽  
Longitudinal Strains

AbstractRecent dose reduction techniques have made retrospective computed tomography (CT) scans more applicable and extracting myocardial function from cardiac computed tomography (CCT) images feasible. However, hyperparameters of generic image intensity-based registration techniques, which are used for tracking motion, have not been systematically optimised for this modality. There is limited work on their validation for measuring regional strains from retrospective gated CCT images and open-source software for motion analysis is not widely available. We calculated strain using our open-source platform by applying an image registration warping field to a triangulated mesh of the left ventricular endocardium. We optimised hyperparameters of two registration methods to track the wall motion. Both methods required a single semi-automated segmentation of the left ventricle cavity at end-diastolic phase. The motion was characterised by the circumferential and longitudinal strains, as well as local area change throughout the cardiac cycle from a dataset of 24 patients. The derived motion was validated against manually annotated anatomical landmarks and the calculation of strains were verified using idealised problems. Optimising hyperparameters of registration methods allowed tracking of anatomical measurements with a mean error of 6.63% across frames, landmarks, and patients, comparable to an intra-observer error of 7.98%. Both registration methods differentiated between normal and dyssynchronous contraction patterns based on circumferential strain ($$p_1=0.0065$$ p 1 = 0.0065 , $$p_2=0.0011$$ p 2 = 0.0011 ). To test whether a typical 10 temporal frames sampling of retrospective gated CCT datasets affects measuring cardiac mechanics, we compared motion tracking results from 10 and 20 frames datasets and found a maximum error of $$8.51\pm 0.8\%$$ 8.51 ± 0.8 % . Our findings show that intensity-based registration techniques with optimal hyperparameters are able to accurately measure regional strains from CCT in a very short amount of time. Furthermore, sufficient sensitivity can be achieved to identify heart failure patients and left ventricle mechanics can be quantified with 10 reconstructed temporal frames. Our open-source platform will support increased use of CCT for quantifying cardiac mechanics.

Sign in / Sign up

Export Citation Format

Share Document