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Feghali JA, Russo RA, Mamou A, Lorentz A, Cantarinha A, Bellin MF, Meyrignac O. Image quality assessment in low-dose COVID-19 chest CT examinations. Acta Radiol 2024; 65:3-13. [PMID: 36744376 PMCID: PMC9905706 DOI: 10.1177/02841851231153797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 12/21/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Low-dose thoracic protocols were developed massively during the COVID-19 outbreak. PURPOSE To study the impact on image quality (IQ) and the diagnosis reliability of COVID-19 low-dose chest computed tomography (CT) protocols. MATERIAL AND METHODS COVID-19 low-dose protocols were implemented on third- and second-generation CT scanners considering two body mass index (BMI) subgroups (<25 kg/m2 and >25 kg/m2). Contrast-to-noise ratios (CNR) were compared with a Catphan phantom. Next, two radiologists retrospectively assessed IQ for 243 CT patients using a 5-point Linkert scale for general IQ and diagnostic criteria. Kappa score and Wilcoxon rank sum tests were used to compare IQ score and CTDIvol between radiologists, protocols, and scanner models. RESULTS In vitro analysis of Catphan inserts showed in majority significantly decreased CNR for the low dose versus standard acquisition protocols on both CT scanners. However, in vivo, there was no impact on the diagnosis: sensitivity and specificity were ≥0.8 for all protocols and CT scanners. The third-generation scanner involved a significantly lower dose compared to the second-generation scanner (CTDIvol of 1.8 vs. 2.6 mGy for BMI <25 kg/m2 and 3.3 vs. 4.6 mGy for BMI >25 kg/m2). Still, the third-generation scanner showed a significantly higher IQ with the low-dose protocol compared to the second-generation scanner (30.9 vs. 28.1 for BMI <25 kg/m2 and 29.9 vs. 27.8 for BMI >25 kg/m2). Finally, the two radiologists had good global inter-reader agreement (kappa ≥0.6) for general IQ. CONCLUSION Low-dose protocols provided sufficient IQ independently of BMI subgroups and CT models without any impact on diagnosis reliability.
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Affiliation(s)
- Joelle A Feghali
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
| | - Roberta A Russo
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
| | - Adel Mamou
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
| | - Axel Lorentz
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
| | - Alfredo Cantarinha
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
| | - Marie-France Bellin
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
- Faculty of Medicine, Paris-Saclay University, Le Kremlin-Bicêtre, France
- Laboratoire d'Imagerie Biomédicale Multimodale (BioMaps), Université Paris-Saclay, CEA, CNRS, Inserm, Service Hospitalier Frédéric Joliot, Orsay, France
| | - Olivier Meyrignac
- Diagnostic and Interventional Radiology Department, AP-HP Paris Saclay University, Bicêtre Hospital, Le Kremlin-Bicêtre, Le Kremlin Bicêtre, France
- Faculty of Medicine, Paris-Saclay University, Le Kremlin-Bicêtre, France
- Laboratoire d'Imagerie Biomédicale Multimodale (BioMaps), Université Paris-Saclay, CEA, CNRS, Inserm, Service Hospitalier Frédéric Joliot, Orsay, France
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Wassipaul C, Janata-Schwatczek K, Domanovits H, Tamandl D, Prosch H, Scharitzer M, Polanec S, Schernthaner RE, Mang T, Asenbaum U, Apfaltrer P, Cacioppo F, Schuetz N, Weber M, Homolka P, Birkfellner W, Herold C, Ringl H. Ultra-low-dose CT vs. chest X-ray in non-traumatic emergency department patients - a prospective randomised crossover cohort trial. EClinicalMedicine 2023; 65:102267. [PMID: 37876998 PMCID: PMC10590727 DOI: 10.1016/j.eclinm.2023.102267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 10/26/2023] Open
Abstract
Background Ultra-low-dose CT (ULDCT) examinations of the chest at only twice the radiation dose of a chest X-ray (CXR) now offer a valuable imaging alternative to CXR. This trial prospectively compares ULDCT and CXR for the detection rate of diagnoses and their clinical relevance in a low-prevalence cohort of non-traumatic emergency department patients. Methods In this prospective crossover cohort trial, 294 non-traumatic emergency department patients with a clinically indicated CXR were included between May 2nd and November 26th of 2019 (www.clinicaltrials.gov: NCT03922516). All participants received both CXR and ULDCT, and were randomized into two arms with inverse reporting order. The detection rate of CXR was calculated from 'arm CXR' (n = 147; CXR first), and of ULDCT from 'arm ULDCT' (n = 147; ULDCT first). Additional information reported by the second exam in each arm was documented. From all available clinical and imaging data, expert radiologists and emergency physicians built a compound reference standard, including radiologically undetectable diagnoses, and assigned each finding to one of five clinical relevance categories for the respective patient. Findings Detection rates for main diagnoses by CXR and ULDCT (mean effective dose: 0.22 mSv) were 9.1% (CI [5.2, 15.5]; 11/121) and 20.1% (CI [14.2, 27.7]; 27/134; P = 0.016), respectively. As an additional imaging modality, ULDCT added 9.1% (CI [5.2, 15.5]; 11/121) of main diagnoses to prior CXRs, whereas CXRs did not add a single main diagnosis (0/134; P < 0.001). Notably, ULDCT also offered higher detection rates than CXR for all other clinical relevance categories, including findings clinically irrelevant for the respective emergency department visit with 78.5% (CI [74.0, 82.5]; 278/354) vs. 16.2% (CI [12.7, 20.3]; 58/359) as a primary modality and 68.2% (CI [63.3, 72.8]; 245/359) vs. 2.5% (CI [1.3, 4.7]; 9/354) as an additional imaging modality. Interpretation In non-traumatic emergency department patients, ULDCT of the chest offered more than twice the detection rate for main diagnoses compared to CXR. Funding The Department of Biomedical Imaging and Image-guided Therapy of Medical University of Vienna received funding from Siemens Healthineers (Erlangen, Germany) to employ two research assistants for one year.
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Affiliation(s)
- Christian Wassipaul
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | | | - Hans Domanovits
- Department of Emergency Medicine, Medical University of Vienna, Austria
| | - Dietmar Tamandl
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | - Helmut Prosch
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | - Martina Scharitzer
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | | | - Ruediger E. Schernthaner
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
- Department of Diagnostic and Interventional Radiology, Clinic Landstrasse, Vienna Healthcare Group, Austria
| | - Thomas Mang
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | - Ulrika Asenbaum
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | - Paul Apfaltrer
- Department of Radiology, Medical University of Graz, Austria
| | - Filippo Cacioppo
- Department of Emergency Medicine, Medical University of Vienna, Austria
| | - Nikola Schuetz
- Department of Emergency Medicine, Medical University of Vienna, Austria
| | - Michael Weber
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | - Peter Homolka
- Centre for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Wolfgang Birkfellner
- Centre for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Christian Herold
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
| | - Helmut Ringl
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria
- Department of Diagnostic and Interventional Radiology, Clinic Donaustadt, Vienna Healthcare Group, Austria
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Han D, Cai J, Heus A, Heuvelmans M, Imkamp K, Dorrius M, Pelgrim GJ, de Jonge G, Oudkerk M, van den Berge M, Vliegenthart R. Detection and size quantification of pulmonary nodules in ultralow-dose versus regular-dose CT: a comparative study in COPD patients. Br J Radiol 2023; 96:20220709. [PMID: 36728829 PMCID: PMC10078877 DOI: 10.1259/bjr.20220709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
OBJECTIVE To evaluate detectability and semi-automatic diameter and volume measurements of pulmonary nodules in ultralow-dose CT (ULDCT) vs regular-dose CT (RDCT). METHODS Fifty patients with chronic obstructive pulmonary disease (COPD) underwent RDCT on 64-multidetector CT (120 kV, filtered back projection), and ULDCT on third-generation dual source CT (100 kV with tin filter, advanced modeled iterative reconstruction). One radiologist evaluated the presence of nodules on both scans in random order, with discrepancies judged by two independent radiologists and consensus reading. Sensitivity of nodule detection on RDCT and ULDCT was compared to reader consensus. Systematic error in semi-automatically derived diameter and volume, and 95% limits of agreement (LoA) were evaluated. Nodule classification was compared by κ statistics. RESULTS ULDCT resulted in 83.1% (95% CI: 81.0-85.2) dose reduction compared to RDCT (p < 0.001). 45 nodules were present, with diameter range 4.0-25.3 mm and volume range 16.0-4483.0 mm3. Detection sensitivity was non-significant (p = 0.503) between RDCT 88.8% (95% CI: 76.0-96.3) and ULDCT 95.5% (95% CI: 84.9-99.5). No systematic bias in diameter measurements (median difference: -0.2 mm) or volumetry (median difference: -6 mm3) was found for ULDCT compared to RDCT. The 95% LoA for diameter and volume measurements were ±3.0 mm and ±33.5%, respectively. κ value for nodule classification was 0.852 for diameter measurements and 0.930 for volumetry. CONCLUSION ULDCT based on Sn100 kV enables comparable detectability of solid pulmonary nodules in COPD patients, at 83% reduced radiation dose compared to RDCT, without relevant difference in nodule measurement and size classification. ADVANCES IN KNOWLEDGE Pulmonary nodule detectability and measurements in ULDCT are comparable to RDCT.
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Affiliation(s)
- Daiwei Han
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jiali Cai
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Anne Heus
- Department of Radiology, Medisch Spectrum Twente, Enschede, The Netherlands
| | - Marjolein Heuvelmans
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Department of Pulmonology, Medisch Spectrum Twente, Enschede, The Netherlands
| | - Kai Imkamp
- Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands
| | - Monique Dorrius
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Gert-Jan Pelgrim
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Gonda de Jonge
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Matthijs Oudkerk
- Institute for Diagnostic Accuracy Research B.V., Groningen, The Netherlands
- University of Groningen, Groningen, The Netherlands
| | - Maarten van den Berge
- Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD, Groningen, The Netherlands
| | - Rozemarijn Vliegenthart
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Cosío BG, Casanova C, Soler-Cataluña JJ, Soriano JB, García-Río F, de Lucas P, Alfageme I, Rodríguez González-Moro JM, Sánchez G, Ancochea J, Miravitlles M. Unravelling young COPD and pre-COPD in the general population. ERJ Open Res 2023; 9:00334-2022. [PMID: 36814553 PMCID: PMC9940715 DOI: 10.1183/23120541.00334-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/24/2022] [Indexed: 11/05/2022] Open
Abstract
Background Chronic obstructive pulmonary disease (COPD) is commonly diagnosed when the airflow limitation is well established and symptomatic. We aimed to identify individuals at risk of developing COPD according to the concept of pre-COPD and compare their clinical characteristics with 1) those who have developed the disease at a young age, and 2) the overall population with and without COPD. Methods The EPISCAN II study is a cross-sectional, population-based study that aims to investigate the prevalence of COPD in Spain in subjects ≥40 years of age. Pre-COPD was defined as the presence of emphysema >5% and/or bronchial thickening by computed chromatography (CT) scan and/or diffusing capacity of the lung for carbon monoxide (D LCO) <80% of predicted in subjects with respiratory symptoms and post-bronchodilator forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) >0.70. Young COPD was defined as FEV1/FVC <0.70 in a subject ≤50 years of age. Demographic and clinical characteristics were compared among pre-COPD, young COPD and the overall population with and without COPD. Results Among the 1077 individuals with FEV1/FVC <0.70, 65 (6.0%) were ≤50 years of age. Among the 8015 individuals with FEV1/FVC >0.70, 350 underwent both D LCO testing and chest CT scanning. Of those, 78 (22.3%) subjects fulfilled the definition of pre-COPD. Subjects with pre-COPD were older, predominantly women, less frequently active or ex-smokers, with less frequent previous diagnosis of asthma but with higher symptomatic burden than those with young COPD. Conclusions 22.3% of the studied population was at risk of developing COPD, with similar symptomatic and structural changes to those with well-established disease without airflow obstruction. This COPD at-risk population is different from those that develop COPD at a young age.
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Affiliation(s)
- Borja G. Cosío
- Department of Medicine, University of Balearic Islands, Palma, Spain,CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain,These authors contributed equally,Corresponding author: Borja G. Cosío ()
| | - Ciro Casanova
- Servicio de Neumología, Hospital Universitario Nuestra Señora de Candelaria, Tenerife, Spain,These authors contributed equally
| | - Juan José Soler-Cataluña
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain,Servicio de Neumología, Hospital Arnau de Vilanova-Lliria, Valencia, Spain
| | - Joan B. Soriano
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain,Servicio de Neumología, Hospital Universitario La Princesa and Universidad Autónoma de Madrid, Madrid, Spain
| | - Francisco García-Río
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain,Servicio de Neumología, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
| | - Pilar de Lucas
- Servicio de Neumología, Hospital General Gregorio Marañon, Madrid, Spain
| | - Inmaculada Alfageme
- Unidad de Gestión Clínica de Neumología, Hospital Universitario Virgen de Valme, Universidad de Sevilla, Seville, Spain
| | | | | | - Julio Ancochea
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain,Servicio de Neumología, Hospital Universitario La Princesa and Universidad Autónoma de Madrid, Madrid, Spain
| | - Marc Miravitlles
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain,Pneumology Department, Hospital Universitari Vall dHebron/Vall d'Hebron Institut de Recerca, Barcelona, Spain
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Brims F, Harris EJA, Kumarasamy C, Ringuet A, Adler B, Franklin P, de Klerk N, Musk B, Murray C. Correlation of lung function with ultra-low-dose CT-detected lung parenchymal abnormalities: a cohort study of 1344 asbestos exposed individuals. BMJ Open Respir Res 2022; 9:9/1/e001366. [PMID: 36581353 PMCID: PMC9806062 DOI: 10.1136/bmjresp-2022-001366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 12/08/2022] [Indexed: 12/30/2022] Open
Abstract
INTRODUCTION Deliberate exposure to medical ionising radiation should be as low as reasonably practicable but the reduction of radiation from CT should be balanced against diagnostic image quality. The ability of ultra-low-dose CT (uLDCT: similar radiation to chest X-ray) to demonstrate low contrast abnormalities (emphysema and interstitial lung abnormality (ILA)) is unclear.The aim of this cross-sectional study was to analyse the lung parenchymal findings from uLDCT scans against physiological measures of respiratory function. METHODS WA Asbestos Review Programme participants were eligible if they had an uLDCT scan and lung function assessment between Janary and December 2018. All scans were performed using a single CT machine and reported using a standardised, semiquantitative synoptic report which includes emphysema and linear fibrosis (ILA) scores. RESULTS Of 1344 participants, median (IQR) age was 72.0 (65.0-78.0) years, the majority were males (84.9%) with mixed occupational asbestos exposure (68.1%). There were 721 (53.6%) with no abnormality, 158 (11.8%) with emphysema, 465 (34.6%) with ILA. Mean radiation dose was 0.12 mSv. There was statistically significant between group differences for all physiological parameters of lung function compared with controls. For instance, the emphysema score significantly correlated with obstructive forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio (r=0.512), per cent predicted FEV1 (r=0.24) and lower diffusion of carbon monoxide (DLCO) (r=0.337). Multivariate modelling demonstrated that increasing age, emphysema and fibrosis scores predicted reduced DLCO (adjusted R2=0.30). DISCUSSION uLDCT-detected parenchymal lung abnormalities correlate strongly with significant changes on lung function testing suggesting the observed CT abnormalities are of physiological and clinical significance.
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Affiliation(s)
- Fraser Brims
- Department of Respiratory Medicine, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia,Curtin University, Institute for Respiratory Health, Perth, Western Australia, Australia
| | - Edward JA Harris
- Department of Respiratory Medicine, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia,Curtin Medical School, Curtin University, Perth, Western Australia, Australia
| | - Chellan Kumarasamy
- Curtin Medical School, Curtin University, Perth, Western Australia, Australia
| | - Amie Ringuet
- Curtin Medical School, Curtin University, Perth, Western Australia, Australia
| | - Brendan Adler
- Envision Medical Imaging, Perth, Western Australia, Australia
| | - Peter Franklin
- School of Global and Population Health, University of Western Australia, Perth, Western Australia, Australia
| | - Nick de Klerk
- School of Global and Population Health, University of Western Australia, Perth, Western Australia, Australia
| | - Bill Musk
- Department of Respiratory Medicine, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - Conor Murray
- ChestRad Medical Imaging, Perth, Western Australia, Australia
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Bonnemaison B, Castagna O, de Maistre S, Blatteau JÉ. Chest CT scan for the screening of air anomalies at risk of pulmonary barotrauma for the initial medical assessment of fitness to dive in a military population. Front Physiol 2022; 13:1005698. [PMID: 36277200 PMCID: PMC9585318 DOI: 10.3389/fphys.2022.1005698] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/21/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction: The presence of intra-pulmonary air lesions such as cysts, blebs and emphysema bullae, predisposes to pulmonary barotrauma during pressure variations, especially during underwater diving activities. These rare accidents can have dramatic consequences. Chest radiography has long been the baseline examination for the detection of respiratory pathologies in occupational medicine. It has been replaced since 2018 by the thoracic CT scan for military diving fitness in France. The objective of this work was to evaluate the prevalence of the pulmonary abnormalities of the thoracic CT scan, and to relate them to the characteristics of this population and the results of the spirometry. Methods: 330 records of military diving candidates who underwent an initial assessment between October 2018 and March 2021 were analyzed, in a single-center retrospective analysis. The following data were collected: sex, age, BMI, history of respiratory pathologies and smoking, treatments, allergies, diving practice, results of spirometry, reports of thoracic CT scans, as well as fitness decision. Results: The study included 307 candidates, mostly male, with a median age of 25 years. 19% of the subjects had abnormal spirometry. We identified 25% of divers with CT scan abnormalities. 76% of the abnormal scans were benign nodules, 26% of which measured 6 mm or more. Abnormalities with an aerial component accounted for 13% of the abnormal scans with six emphysema bullae, three bronchial dilatations and one cystic lesion. No association was found between the presence of nodules and the general characteristics of the population, whereas in six subjects emphysema bullae were found statistically associated with active smoking or abnormal spirometry results. Conclusion: The systematic performance of thoracic CT scan in a young population free of pulmonary pathology revealed a majority of benign nodules. Abnormalities with an aerial component are much less frequent, but their presence generally leads to a decision of unfitness. These results argue in favor of a systematic screening of aeric pleuro-pulmonary lesions during the initial assessment for professional divers.
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Affiliation(s)
- Brieuc Bonnemaison
- Service de Médecine Hyperbare et d’Expertise Plongée (SMHEP), Hôpital d'Instruction des Armées Sainte-Anne, Toulon, France
| | - Olivier Castagna
- Equipe de Recherche Subaquatique et Hyperbare, Institut de Recherche biomédicale des armées, Toulon, France
- Laboratoire Motricité Humaine Expertise Sport Santé, UPR 6312, Nice, France
| | - Sébastien de Maistre
- Cellule plongée humaine et Intervention sous la Mer (CEPHISMER), Force d’action navale, Toulon, France
| | - Jean-Éric Blatteau
- Service de Médecine Hyperbare et d’Expertise Plongée (SMHEP), Hôpital d'Instruction des Armées Sainte-Anne, Toulon, France
- *Correspondence: Jean-Éric Blatteau,
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Döllinger F, Elsner A, Hübner RH. [Computed tomographic imaging in chronic obstructive pulmonary disease : What pulmonologists and thoracic surgeons want to know]. RADIOLOGIE (HEIDELBERG, GERMANY) 2022; 62:747-757. [PMID: 35819467 DOI: 10.1007/s00117-022-01042-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
Chronic obstructive pulmonary disease (COPD) begins with chronic inflammation of the bronchial system and leads to the development of emphysema in many patients. COPD patients are characterized by reduced performance, dyspnea in the context of an obstructive respiratory disorder and increased susceptibility to infections. COPD has a major impact on public health, as it is very common and many patients die from it. The most important preventable cause of COPD is tobacco smoke inhalation, which is why consistent smoking cessation is the most important component of any COPD treatment. There is no causal therapy, but in severely symptomatic patients with advanced emphysema, respiratory mechanics can be improved by lung volume reduction if all conservative treatment options have been exhausted. Diagnostic imaging is of great importance in the care of COPD patients. This article summarizes which indications warrant the performance of computed tomography (CT) and what we should pay special attention to during image analysis in order to provide optimal advice to our clinical partners.
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Affiliation(s)
- Felix Döllinger
- Klinik für Radiologie, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Deutschland.
| | - Aron Elsner
- Chirurgische Klinik, Charité Universitätsmedizin Berlin, Berlin, Deutschland
| | - Ralf-Harto Hübner
- Medizinische Klinik m. S. Infektiologie und Pneumologie, Charité Universitätsmedizin Berlin, Berlin, Deutschland
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Vliegenthart R, Fouras A, Jacobs C, Papanikolaou N. Innovations in thoracic imaging: CT, radiomics, AI and x-ray velocimetry. Respirology 2022; 27:818-833. [PMID: 35965430 PMCID: PMC9546393 DOI: 10.1111/resp.14344] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 07/08/2022] [Indexed: 12/11/2022]
Abstract
In recent years, pulmonary imaging has seen enormous progress, with the introduction, validation and implementation of new hardware and software. There is a general trend from mere visual evaluation of radiological images to quantification of abnormalities and biomarkers, and assessment of ‘non visual’ markers that contribute to establishing diagnosis or prognosis. Important catalysts to these developments in thoracic imaging include new indications (like computed tomography [CT] lung cancer screening) and the COVID‐19 pandemic. This review focuses on developments in CT, radiomics, artificial intelligence (AI) and x‐ray velocimetry for imaging of the lungs. Recent developments in CT include the potential for ultra‐low‐dose CT imaging for lung nodules, and the advent of a new generation of CT systems based on photon‐counting detector technology. Radiomics has demonstrated potential towards predictive and prognostic tasks particularly in lung cancer, previously not achievable by visual inspection by radiologists, exploiting high dimensional patterns (mostly texture related) on medical imaging data. Deep learning technology has revolutionized the field of AI and as a result, performance of AI algorithms is approaching human performance for an increasing number of specific tasks. X‐ray velocimetry integrates x‐ray (fluoroscopic) imaging with unique image processing to produce quantitative four dimensional measurement of lung tissue motion, and accurate calculations of lung ventilation. See relatedEditorial
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Affiliation(s)
- Rozemarijn Vliegenthart
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.,Data Science in Health (DASH), University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | | | - Colin Jacobs
- Department of Medical Imaging, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Nickolas Papanikolaou
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal.,AI Hub, The Royal Marsden NHS Foundation Trust, London, UK.,The Institute of Cancer Research, London, UK
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Quantitative Computed Tomography: What Clinical Questions Can it Answer in Chronic Lung Disease? Lung 2022; 200:447-455. [PMID: 35751660 PMCID: PMC9378468 DOI: 10.1007/s00408-022-00550-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 06/07/2022] [Indexed: 01/27/2023]
Abstract
Quantitative computed tomography (QCT) has recently gained an important role in the functional assessment of chronic lung disease. Its capacity in diagnostic, staging, and prognostic evaluation in this setting is similar to that of traditional pulmonary function testing. Furthermore, it can demonstrate lung injury before the alteration of pulmonary function test parameters, and it enables the classification of disease phenotypes, contributing to the customization of therapy and performance of comparative studies without the intra- and inter-observer variation that occurs with qualitative analysis. In this review, we address technical issues with QCT analysis and demonstrate the ability of this modality to answer clinical questions encountered in daily practice in the management of patients with chronic lung disease.
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Emphysema Quantification Using Ultra-Low-Dose Chest CT: Efficacy of Deep Learning-Based Image Reconstruction. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58070939. [PMID: 35888658 PMCID: PMC9317892 DOI: 10.3390/medicina58070939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/03/2022] [Accepted: 07/14/2022] [Indexed: 11/17/2022]
Abstract
Background and Objectives: Although reducing the radiation dose level is important during diagnostic computed tomography (CT) applications, effective image quality enhancement strategies are crucial to compensate for the degradation that is caused by a dose reduction. We performed this prospective study to quantify emphysema on ultra-low-dose CT images that were reconstructed using deep learning-based image reconstruction (DLIR) algorithms, and compared and evaluated the accuracies of DLIR algorithms versus standard-dose CT. Materials and Methods: A total of 32 patients were prospectively enrolled, and all underwent standard-dose and ultra-low-dose (120 kVp; CTDIvol < 0.7 mGy) chest CT scans at the same time in a single examination. A total of six image datasets (filtered back projection (FBP) for standard-dose CT, and FBP, adaptive statistical iterative reconstruction (ASIR-V) 50%, DLIR-low, DLIR-medium, DLIR-high for ultra-low-dose CT) were reconstructed for each patient. Image noise values, emphysema indices, total lung volumes, and mean lung attenuations were measured in the six image datasets and compared (one-way repeated measures ANOVA). Results: The mean effective doses for standard-dose and ultra-low-dose CT scans were 3.43 ± 0.57 mSv and 0.39 ± 0.03 mSv, respectively (p < 0.001). The total lung volume and mean lung attenuation of five image datasets of ultra-low-dose CT scans, emphysema indices of ultra-low-dose CT scans reconstructed using ASIR-V 50 or DLIR-low, and the image noise of ultra-low-dose CT scans that were reconstructed using DLIR-low were not different from those of standard-dose CT scans. Conclusions: Ultra-low-dose CT images that were reconstructed using DLIR-low were found to be useful for emphysema quantification at a radiation dose of only 11% of that required for standard-dose CT.
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Ferri F, Bouzerar R, Auquier M, Vial J, Renard C. Pulmonary emphysema quantification at low dose chest CT using Deep Learning image reconstruction. Eur J Radiol 2022; 152:110338. [DOI: 10.1016/j.ejrad.2022.110338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 04/06/2022] [Accepted: 05/01/2022] [Indexed: 11/29/2022]
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Hasegawa A, Ishihara T, Pan T, Ropp AM, Winkler M, Sneider MB. Impact of pixel value truncation on image quality of low dose chest CT. Med Phys 2022; 49:2979-2994. [PMID: 35235216 DOI: 10.1002/mp.15589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/04/2022] [Accepted: 02/25/2022] [Indexed: 11/11/2022] Open
Abstract
PURPOSE In some noisy low-dose CT lung cancer screening images, we noticed that the CT density values of air were increased and the visibility of emphysema was distinctly decreased. By examining histograms of these images, we found that the CT density values were truncated at -1,024 HU. The purpose of this study was to investigate the effect of pixel value truncation on the visibility of emphysema using mathematical models. METHODS AND MATERIALS Assuming CT noise follows a normal distribution, we derived the relationship between the mean CT density value and the standard deviation (SD) when the pixel values below -1,024 HU are truncated and replaced by -1,024 HU. To validate our mathematical model, 20 untruncated phantom CT images were truncated by simulation, and the mean CT density values and SD of air in the images were measured and compared with the theoretical values. In addition, the mean CT density values and SD of air were measured in 100 cases of real clinical images obtained by GE, Siemens, and Philips scanners, respectively, and the agreement with the theoretical values was examined. Next, the contrast-to-noise ratio (CNR) between air (-1,000 HU) and lung parenchyma (-850 HU) was derived from the mathematical model in the presence and absence of truncation as a measure of the visibility of emphysema. In addition, the radiation dose ratios required to obtain the same CNR in the case with and without truncation were also calculated. RESULTS The mathematical model revealed that when the pixel values are truncated, the mean CT density values are proportional to the noise magnitude when the magnitude exceeds a certain level. The mean CT density values and SD measured in the images with pixel values truncated by simulation and in the real clinical images acquired by GE and Philips scanners agreed well with the theoretical values from our mathematical model. In the Siemens images, the measured and theoretical values agreed well when a portion of the truncated values were replaced by random values instead of simply replacing by -1,024 HU. The CNR of air and lung parenchyma was lowered by truncating CT density values compared to that of no truncation. Furthermore, it was found that higher radiation dose was required to obtain the same CNR with truncation as without. As an example, when the noise SD was 60 HU, the radiation dose required for the GE and Philips truncation method was about 1.2 times higher than that without truncation, and that for the Siemens truncation method was about 1.4 times higher. CONCLUSIONS It was demonstrated mathematically that pixel value truncation causes a brightening of the mean CT density value and decreases the CNR of emphysema. Our results indicate that it is advisable to turn off truncation at -1,024 HU, especially when scanning at low and ultra-low radiation doses in the thorax. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Akira Hasegawa
- Department of Radiological Technology, National Cancer Center Japan, Tokyo, 104-0045, Japan.,AlgoMedica, Inc., Sunnyvale, CA, 94085, USA
| | - Toshihiro Ishihara
- Department of Radiological Technology, National Cancer Center Japan, Tokyo, 104-0045, Japan
| | - Tinsu Pan
- Department of Imaging Physics, M.D. Anderson Cancer Center, University of Texas, Houston, TX, 77030, USA
| | - Alan M Ropp
- Department of Radiology and Medical Imaging, University of Virginia Health, Charlottesville, VA, 22908, USA
| | - Michael Winkler
- Department of Radiology and Imaging, Medical College of Georgia at Augusta University, Augusta, GA, 30912, USA
| | - Michael B Sneider
- Department of Radiology and Medical Imaging, University of Virginia Health, Charlottesville, VA, 22908, USA
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