Comparison of the Ultra-low-dose Veo Algorithm With the Gold Standard Filtered Back Projection for Detecting Pulmonary Asbestos-related Conditions
Asbestos fibers were intensively used throughout the 20th century and remain prevalent in developing countries. However, asbestos exposure induces a variety of benign and malignant pleural and lung diseases. The most common asbestos-induced neoplasm is lung cancer. Moreover, thin-section computed tomography (CT) is more sensitive than a chest x-ray for detecting early asbestos-related conditions. Increased exposure to radiation underpins the consequences of cancer induction. However, reducing CT doses increases image noise from the filtered back projection (FBP) reconstruction. Strategies to reduce radiation exposure include the use of iterative reconstruction algorithms. A new algorithm called VeoTM (General Electric Healthcare, Milwaukee, MI, USA) decreases the image noise up to 70% compared with the gold standard FBP model. Moreover, Veo improves spatial resolution with excellent detection of low and high contrast objects from a CT Dose Index (CTDIvol) equal to 0.3 mGy.
The objective of the present study is to compare Veo with the gold standard FBP for detecting pulmonary asbestos-related conditions among workers previously exposed to asbestos. Comparisons included radiation delivered and image quality.
Panoramica dello studio
Stato
Condizioni
Intervento / Trattamento
Descrizione dettagliata
Asbestos-exposed workers will be recruited following referral to our radiology department for the evaluation of asbestos-related disease. CT examinations will be performed with a 64-slice CT system (Discovery CT 750HD; GE Healthcare, Milwaukee, WI) and will consist of two successive acquisitions. Each examination, the normal-dose (FBP acquisition) and ultra-low-dose (Veo acquisition) spiral CT, will be performed in supine position, on the entire thorax, at full inspiration and without contrast agent injection.
In order to perform the two acquisitions without increasing radiation, standard acquisition will be performed with the same kV with mA equal to patient's body weight minus 10. To conserve image quality, 60 mA will be the inferior limit. The other CT parameters will be rotation time 0.5 s and pitch 1.375. Image data will be reconstructed with FBP algorithm.
The Veo acquisition will be performed with constant CT parameters including: a tube voltage of 100 kV, a tube current of 20 mA, pitch of 0.984 and rotation time 0.4 s. Image data will be reconstructed with the Veo algorithm.
Each CT acquisition will be viewed independently by two experienced radiologists (2 to 7 years of experience). The low-dose images with Veo reconstruction will be interpreted before the standard CT and on separate weeks to minimize recall bias. Then, the more experienced radiologist will evaluate the detection and characterization of pleuroparenchymal abnormalities by a second and simultaneous reading of the Veo and FBP acquisitions. Because FBP images are benchmark practice, when a lesion will be found only on Veo images, it will be regarded as a false positive.
The following asbestos-related pleural and parenchymal abnormalities will be recorded as present or absent. Pleural abnormalities considered will be: pleural plaques, diffuse pleural thickening and pleural effusion.
CT features of asbestosis will include subpleural dots and branching opacities, curvilinear subpleural lines, areas of ground glass opacities, septal lines, reticulations and honeycombing.
Presence of nodules will also be recorded. We will note for each abnormality: localization (side, table position) and nature (non-solid, part-solid, solid or calcified).
Tipo di studio
Iscrizione (Effettivo)
Fase
- Fase 4
Contatti e Sedi
Luoghi di studio
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Clermont-Ferrand, Francia, 63003
- Chu Clermont-Ferrand
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Criteri di partecipazione
Criteri di ammissibilità
Età idonea allo studio
Accetta volontari sani
Sessi ammissibili allo studio
Descrizione
Inclusion Criteria:
- asbestos-exposed workers
- ability to give a written informed consent
Exclusion Criteria:
- - previous history of cancer
- previous history of thoracic surgery
- other interstitial pathology known
Piano di studio
Come è strutturato lo studio?
Dettagli di progettazione
- Scopo principale: Diagnostico
- Assegnazione: Randomizzato
- Modello interventistico: Assegnazione di gruppo singolo
- Mascheramento: Separare
Armi e interventi
Gruppo di partecipanti / Arm |
Intervento / Trattamento |
|---|---|
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Sperimentale: VeoTM
A new algorithm called VeoTM (General Electric Healthcare, Milwaukee, MI, USA) decreases the image noise up to 70% compared with the gold standard FBP model.
Moreover, Veo improves spatial resolution with excellent detection of low and high contrast objects from a CT Dose Index (CTDIvol) equal to 0.3 mGy
|
The objective of the present study is to compare Veo with the gold standard FBP for detecting pulmonary asbestos-related conditions among workers previously exposed to asbestos.
Comparisons included radiation delivered and image quality.
|
|
Altro: gold standard FBP model
The objective of the present study is to compare Veo with the gold standard FBP for detecting pulmonary asbestos-related conditions among workers previously exposed to asbestos.
Comparisons included radiation delivered and image quality
|
The objective of the present study is to compare Veo with the gold standard FBP for detecting pulmonary asbestos-related conditions among workers previously exposed to asbestos.
Comparisons included radiation delivered and image quality.
|
Cosa sta misurando lo studio?
Misure di risultato primarie
Misura del risultato |
Misura Descrizione |
Lasso di tempo |
|---|---|---|
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Pleural and parenchymal abnormalities
Lasso di tempo: at day 1
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The kappa coefficient will be used to measure agreement for categorical parameters and Pearson's correlation coefficient and Lin concordance correlation coefficient for quantitative data.
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at day 1
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Misure di risultato secondarie
Misura del risultato |
Misura Descrizione |
Lasso di tempo |
|---|---|---|
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Radiation dose
Lasso di tempo: at day 1
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The dose length product (DLP) will be recorded.
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at day 1
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Quality images assessment
Lasso di tempo: at day 1
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Respiratory artifacts will be graded on a three-point scale (1 = negligible, 2 = moderate, 3 = salient). Images noise will be studied in the axial and coronal planes. A similar scale will be used for subjective image quality in the mediastinum and parenchyma windows. Objective image noise (Standard Deviation) and average CT numbers (in Hounsfield's units) will be measured with circular regions of interest (ROI) on different anatomical levels, 10 mm in diameter. The signal to noise ratio (SNR) will also be calculated using the equation SNR = CT numbers / noise. |
at day 1
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Collaboratori e investigatori
Pubblicazioni e link utili
Studiare le date dei record
Studia le date principali
Inizio studio
Completamento primario (Effettivo)
Completamento dello studio (Effettivo)
Date di iscrizione allo studio
Primo inviato
Primo inviato che soddisfa i criteri di controllo qualità
Primo Inserito (Stima)
Aggiornamenti dei record di studio
Ultimo aggiornamento pubblicato (Stima)
Ultimo aggiornamento inviato che soddisfa i criteri QC
Ultimo verificato
Maggiori informazioni
Termini relativi a questo studio
Parole chiave
Altri numeri di identificazione dello studio
- CHU-0166
- 2012-A00618-35
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