Thoracoabdominal Arortic CTA Study

Study Overview
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Brief Summary
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The purpose of this study is to compare the contrast agents and imaging techniques used for thoracoabdominal aortic imaging in CT. Imaging parameters and contrast volume are changed and adjusted based on the contrast agent, since contrast agents have varying iodine concentrations. If the contrast iodine concentration is higher, it may be possible to adjust the imaging parameters and lower the overall radiation dose to the patient.

Official Title
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Comparison of High Iodine Concentration Contrast Material (Isovue 370) vs Standard Protocol (Isovue 300) in Thoracoabdominal Aortic Computed Tomographic Angiography (CTA) for Radiation Dose Reduction

Conditions
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Thoracic Aortic Aneurysm

Intervention / Treatment
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* Drug: Isovue


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing thoracoabdominal aortic (TAA) CTA Able to provide informed consent Body Mass Index (BMI) equal to or less than 30 Exclusion Criteria: Creatinine greater than 2.0 Allergy to contrast media Pregnant women

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: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Isovue 300 75mL<br>Isovue 300 75mL injected 120 kVp 250 mAs | Drug: Isovue<br>* iodine contrast<br>|
| Active Comparator: Isovue 370 75mL<br>Isovue 370 75mL injected 100 kVp 240 mAs | Drug: Isovue<br>* iodine contrast<br>|
| Active Comparator: Isovue 370 60mL<br>Isovue 370 60mL injected 100 kVp 240 mAs | Drug: Isovue<br>* iodine contrast<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiation Dose |  | 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Signal to Noise Ratio | Calculated as the ratio of mean attenuation values divided by the standard deviation of attenuation values gathered using a circular region of interest in the thoracic aorta. | 30 minutes | 
| Hounsfield Unit Attenuation Values | Grayscale values on CT scans are given as Hounsfield units. These Hounsfield units reflect the attenuation of x-ray beams traversing the aortic lumen. We will use Hounsfield units to assess whether the tool contrast agents achieve similar attenuation characteristics essential for diagnosing aortic abnormalities. We will use circular regions of interest in the thoracic aorta to extract the Hounsfield unit measurements. | 30 minutes | 
| Variation in Contrast for the Entire Vascular System (coV) | The change in contrast was measured at the proximal segment of the aorta and at the Iliac arteries for each subject. | 30 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Suspected or confirmed, TAA, Computed tomography angiography, CTA, Contrast agent, Radiation dose, Thoracoabdominal aortic aneurysm