Physical examination may help characterize the "noisy breathing" and help differentiate it from other more common problems such as asthma.
With a vascular ring, the noisy breathing may be heard both during inspiration and expiration, while in asthma, the noise is mainly at the end of expiration.
Occasionally, physical examination will detect an abnormally weak pulse in an arm or the legs due to narrowing in a part of the anomalous blood vessels. Listening to the chest for murmurs is often included to assess the need for more thorough evaluation for associated cardiac anomalies (which are uncommon).
A chest X-ray is often performed as a part of the initial evaluation, and if the aortic arch appears to be right-sided, a vascular ring should be suspected. The identification of the side of the aortic arch on the plain chest X-ray, though, may be difficult in some children, particularly infants.
Patients with swallowing difficulties should undergo a barium swallow as part of the initial evaluation. This will typically show abnormal compression of the middle part of the esophagus characteristic for a vascular ring.
A barium study that shows classic features of a vascular ring, along with a chest X-ray showing a right-sided aortic arch is generally all that is necessary to proceed with operation.
A chest CT or MRI will often be ordered to show the relationship of the vessels, the trachea and the esophagus.
When breathing symptoms predominate, bronchoscopy may be performed that will often demonstrate extrinsic, sometime pulsatile compression of the trachea.