Computed Tomography Dose Reduction Using Sequential or Fast Pitch Sprial Technique

Study Overview
=================
Brief Summary
-----------------
This is a prospective, controlled observational trial of patients undergoing clinically indicated cardiothoracic computed tomography (CT), including pulmonary or aortic angiography and coronary CT angiography (CCTA).

Detailed Description
-----------------
The development of a novel CT scanner capable of sequential or fast-pitch spiral techniques in most patients (Siemens Definition Flash) represents a potentially crucial technical innovation at a particularly critical juncture. National healthcare systems are under pressure to deliver accurate and cost-effective diagnosis of an increasing number of patients and CT angiography in various settings is a proven, highly accurate technique that has been shown to improve diagnostic efficiency and reduce the cost of care. However, there has been increasing concern about the lifetime attributable risk of cancer from radiation related to diagnostic procedures. Such concern extends to other radiation-based procedures that contribute to the cumulative lifetime radiation exposure of patients. The Flash scanner holds the promise of substantially reducing exposure resulting from a variety of examinations. The CT DOSE multicenter trial is therefore designed to validate the extent of dose reduction attendant to the use of the Flash scanner in cardiothoracic scanning, and to determine whether image quality is preserved in spite of significant dose reduction.

Official Title
-----------------
Computed Tomography Dose Reduction Using Sequential or Fast Pitch Sprial Technique Employed in Cardiothoracic Imaging

Conditions
-----------------
Coronary Artery Disease, Aortic Aneurysm, Pulmonary Embolism

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Scans from patients undergoing clinically indicated pulmonary angiography, aortography and/or CCTA. Age greater than or equal to 18 years. Exclusion Criteria: No exclusions

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Control Group<br>Data from patients in the control group will be obtained retrospectively from patient medical records and stored image data | |
| Prospective Patient Group<br>Data from patients in the Flash group will be obtained prospectively from scanner consoles and medical records. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiation dose | The primary endpoint is radiation dose, measured as dose-length-product (DLP, in mGy∙cm) and effective radiation dose, calculated as DLP x 0.014 (in mSv). | Time of CT scan | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of Image Quality | Signal noise (standard deviation of attenuation in Hounsfield units) will be determined in regions of interest in: A) air anterior to the chest wall, B) mid-LV septum and C) mid thoracic aorta or main PA. This will be done in a sequential sample of every 5th case (approximately 600 cases total). | Time of CT Scan | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
coronary artery disease, CT scan, coronary angiography, chest pain, aortic aneurysm, pulmonary embolism