Does MRA for ruling out Takayasu arteritis require with contrast, without contrast, or with and without contrast?

From the Guidelines

MRA for ruling out Takayasu arteritis requires imaging with and without contrast.

Key Points

• Contrast-enhanced MRA is particularly useful in the evaluation of inflammatory conditions, such as Takayasu arteritis, as it can detect wall enhancement, a sign of active disease 1.
• MRA without IV contrast has some utility in the diagnosis of inflammatory vascular conditions, but it is unable to provide an assessment of wall enhancement, an important marker in many inflammatory conditions 1.
• The use of both contrast-enhanced and non-contrast MRA allows for a comprehensive evaluation of the aorta, including the detection of aneurysms, edema, perivascular stranding, gas, and disrupted calcifications, as well as the assessment of wall enhancement 1.
• MRI with gadolinium contrast enhancement is the preferred noninvasive modality for the diagnosis of aortitis, revealing late gadolinium enhancement, vessel wall edema, and wall thickening using T2-weighted imaging 1.
• MRI is the preferred imaging modality for Takayasu arteritis, with FDG-PET, CT, or ultrasound as alternatives 1.
• The addition of contrast-enhanced sequences improved the sensitivity of MRA in detecting Takayasu arteritis from 79% to 92% 1.

From the Research

MRA for Ruling Out Takayasu Arteritis

• The use of contrast-enhanced MRA is supported by several studies for assessing disease activity and detecting vessel wall inflammation in Takayasu arteritis 2, 3, 4.
• Contrast-enhanced MR imaging has been shown to provide information about disease activity, which may be useful in the diagnosis and treatment of Takayasu's arteritis 2.
• The combination of MRA with and without contrast may be useful for evaluating the vascular tree non-invasively and detecting subtle arteritic changes and stenotic lesions in the early phase of the disease 3.
• However, contrast-enhanced MRI has less utility in assessing disease activity in Takayasu arteritis, and its ability to accurately detect active disease is limited 4.
• Other imaging modalities, such as MRI, magnetic resonance angiography (MRA), Doppler ultrasound, CT, and positron emission tomography (PET), may also be useful for evaluation of Takayasu arteritis 5, 6.

Imaging Modalities for Takayasu Arteritis

• MRI/A can provide information on arterial wall anatomy and obtain a generalized arterial survey in Takayasu arteritis, without the risks of arterial puncture, iodinated contrast load, and radiation exposure 5.
• Ultrasound can be helpful in detecting sub-millimeter changes in wall thickness of the carotid arteries and in differentiating Takayasu arteritis from atherosclerotic disease 5.
• CT angiography can be used to detect areas of aortic wall thickening and obtain a generalized survey of the aorta and its proximal branches for areas of stenosis, but it provides less detailed resolution than ultrasound and incurs the risks of contrast administration 5.
• PET scanning may provide valuable information about cellular activity within an inflamed arterial wall before morphologic changes on other imaging studies 5.