Magnetic Resonance Imaging Findings in a Positron Emission Tomography-Positive Thoracic Aortic Aneurysm

Abstract

Diffusion-weighted MRI (DW-MRI) and ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) findings are described in a patient with a thoracic aortic aneurysm. Both examinations have the ability to noninvasively assess biological processes associated with aneurysm instability and therefore to potentially impact clinical decision-making regardless of the vessel size. Despite similarities between images on both techniques, FDG-PET evaluates glycolysis, while DW-MRI evaluates cell density, edema, and perfusion. Longitudinal studies including larger patient numbers are needed to investigate the temporal continuum and clinical significance of these findings.

Key Words

Magnetic resonance imaging - Positron emission tomography - Aortic aneurysm

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