CODP Imaging From a Dose Perspective

Study Overview
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Brief Summary
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The noncontrast-enhanced chest computed tomography (CT) is an emerging diagnostical tool in patient with chronic obstructive pulmonary disease (COPD). As shown in previous studies and pointed out by the Fleischner society, an additional scan in expiration reflects the pathophysiology of this complex disease better and extends the clinical information of the CT. Nevertheless, this scan is leading to an increase in radiation dose. But currently it is unclear if this increased radiation dose is proportional to the additional clinical value when compared to inspiration-only protocols. Therefore, the aim of this study was to compare the organ specific radiation doses of a combined inspiration-expiration CT on a 3rd generation dual-source scanner with noncontrast-enhanced chest CTs of two clinical routine scanners. Therefore, the radiation doses of nearly 2000 chest CTs have been evaluated.

Official Title
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CODP Imaging From a Dose Perspective - Effective Organ Doses of a Combined Inspiration-expiration Protocol on a 3rd Generation Dual-source CT

Conditions
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Radiation

Intervention / Treatment
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* Diagnostic Test: computed tomography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: noncontrast-enhanced chest CT performed on one of the named devices imaging performed between August 2014 and September 2017 CT protocol used as previously specified Exclusion Criteria: -
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 16-slice CT scanner<br>1426 patients that have received a noncontrast-enhanced chest CT on our 16-slice clinical routine CT scanner in inspiration only. | Diagnostic Test: computed tomography<br>* noncontrast-enhanced chest computed tomography<br>|
| 2nd generation dual-source CT<br>320 patients that have received a noncontrast-enhanced chest CT on our second generation dual-source CT scanner in inspiration only. | Diagnostic Test: computed tomography<br>* noncontrast-enhanced chest computed tomography<br>|
| 3rd generation dual-source CT<br>211 patients that have received a noncontrast-enhanced chest CT on our third generation dual-source CT scanner in inspiration and expiration. | Diagnostic Test: computed tomography<br>* noncontrast-enhanced chest computed tomography<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| organ specific radiation doses | Organ specific radiation doses of 17 individual organs | The organ dose calculations have been performed retrospectively. Therefore, the time frame is variable. The time set for the final outcome calculations was September 2017. Therefore, the time frame varies between 3 years and 1 week. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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COPD, Computed tomography, Expiration, organ specific radiation dose