CT Chest WITH Contrast (CTA) is Required for Aortic Root Dilation

Importance of Contrast in CTA

The American College of Radiology recommends contrast-enhanced CTA for assessing the aortic lumen, wall, and surrounding structures, which is necessary for accurate diagnosis and treatment planning 1
CTA is the reference standard for aortic aneurysm diagnosis with near 100% sensitivity and 98% specificity for detecting thoracic aortic pathology 2
The 3D dataset from CTA allows for precise measurements perpendicular to the flow lumen, which is essential for accurate assessment of aortic root dimensions 1, 2

The American College of Radiology suggests that ECG-gated CTA is particularly important for the ascending aorta and aortic root to minimize cardiac motion artifacts and ensure accurate orthogonal measurements 4, 5, 1, 2
Multiplanar reconstructions and 3D rendering are essential components of the CTA examination for comprehensive evaluation 1, 2
The scan should include the entire thoracic aorta from the aortic root through the descending aorta 1

The American College of Radiology recommends MRA as the appropriate alternative when patients have contraindications to iodinated contrast, such as severe renal insufficiency 2
MRA provides comparable accuracy to CTA for thoracic aortic measurements, with no significant differences between the two modalities 4, 5, 8
Non-contrast MRA sequences can provide excellent visualization of the aortic lumen without requiring gadolinium contrast 4, 5, 8

The American College of Radiology advises against ordering non-contrast CT chest for suspected aortic root dilation, as it will not provide adequate assessment of the aortic lumen and will likely require repeat imaging with contrast 3, 1
Ensure ECG gating is used for aortic root imaging to avoid motion artifacts that can lead to inaccurate measurements 4, 5, 1, 2
Measurements must be made perpendicular to the long axis of the aorta using multiplanar reconstructions for standardized evaluation 1, 2