Computerised Tomography (CT)
Aortic dissection is diagnosed on CT by identifying two distinct lumens with a visible intimal flap. It can also delineate branch vessel involvement, visualise the entire aorta and has a sensitivity approaching 100% [1].
Intimal flaps
The arrows on the image demonstrate the intimal flaps in both the ascending aorta (anterior) and the descending aorta (posterior). ‘TL’ represents the true lumen and ‘FL’ the false lumen. Note the majority of the contrast is almost always in the true lumen.
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Lumens
The image illustrates two distinct lumens at the level of the arch of the aorta.
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Dissection flap
The arrow on the image demonstrates a dissection flap within the left common carotid artery as it comes off the arch of the aorta.
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Peridcardial fluid
CT will also reveal pericardial fluid which is not a direct confirmatory test for aortic dissection but will suggest this diagnosis in the right clinical context. The white arrow highlights the pericardial fluid.