On Dose Efficiency of Modern CT-scanners in Chest Scans

Study Overview
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Brief Summary
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CT scans of the chest / thorax are of great importance both in the initial diagnosis and in the follow-up of pulmonary or thoracic diseases. As an example, CT angiography of the pulmonary arteries (CTPA) is worldwide considered to be gold standard test in patients with a suspicion for pulmonary embolism. The aim of this study is to measure and compare dose efficiency of modern CT scanners for unenhanced and contrast-enhanced scan protocols of the chest/thorax. Patients who are referred for a CT of the chest/thorax will be randomly assigned to one of the three CT scanners currently in use at our institution.

Official Title
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On Dose Efficiency of Modern CT-scanners in Chest Scans- a Prospective, Randomized Study

Conditions
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Pneumonia, Lung Cancer, Pulmonary Embolism, Pulmonary Disease, Aortic Stenosis

Intervention / Treatment
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* Diagnostic Test: Imaging on Scanner with Spectral Imaging Capabilities
* Diagnostic Test: CT Scan using an Energy-Integrating Detector CT (128 slice MDCT)
* Diagnostic Test: CT Scan using an Energy-Integrating Detector CT (20-slice MDCT)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient is referred for an unenhanced CT OR contrast-enhanced CT of the chest/thorax confirmed by a board-certified radiologist ('justifying indication' according to German/European radiation protection law) AND patient is at least 18 years of age AND patient (is able to give informed consent and) has given informed consent. Exclusion Criteria: high degree of medical urgency (i.e. patient cannot be consented for iv contrast according to routine procedures) known or suspected pregnancy, or lactating . contraindications for contrast agent (renal failure, allergy, hyperthyroidism)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomization of patients referred for a CT scan of the thorax on one of three CT scanners routinely used for this purpose in our department
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Scanner 1<br>Imaging performed on scanner 1: Photon-Counting Detector CT | Diagnostic Test: Imaging on Scanner with Spectral Imaging Capabilities<br>* Patients will undergo imaging on a modern CT scanner with spectral imaging capabilities. A dose neutral spectral acquisition mode will routinely be used. Contrast material protocol and scan ranges are similar in all three arms.<br>* Other names: CT Scan using a Photon-Counting Detector CT: Naeotom Alpha (Siemens Healthineers);|
| Other: Scanner 2<br>Imaging performed on scanner 2: Energy-Integrating Detector CT (128-slice) | Diagnostic Test: CT Scan using an Energy-Integrating Detector CT (128 slice MDCT)<br>* Patients will undergo imaging on a modern 128-slice CT scanner (Siemens Healthineers) with energy-integrating detector and without spectral acquisition mode. Contrast material protocol and scan ranges are similar in all three arms.<br>|
| Other: Scanner 3<br>Imaging performed on scanner 3: Energy-Integrating Detector CT (20-slice) | Diagnostic Test: CT Scan using an Energy-Integrating Detector CT (20-slice MDCT)<br>* Patients will undergo imaging on a modern 20-slice CT scanner (Siemens Healthineers) with energy-integrating detector and without spectral acquisition mode. Contrast material protocol and scan ranges are similar in all three arms.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Parameters of Objective Image Quality | Measured as signal, image noise and modulation transfer function equivalent parameters | 1 year | 
| Parameters of Radiation Dose | measured as x-ray tube parameters such as dose length product (DLP) | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Subjective Image Quality Evaluation (entire cohort and for individual disease groups) | measured by blinded evaluation by radiologists | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Spectral CT, Computed Tomography, Dose efficiency