Neck MRA (blood vessel MRI, with contrast)

What it is

A great many strokes start in the neck rather than the head. Plaque builds where the carotid artery divides, narrowing the channel and shedding debris that travels upstream, and a tear in the wall of a carotid or vertebral artery — which can follow a whiplash injury, a fall, or sometimes nothing obvious at all — does much the same thing. This study is the map of that stretch of plumbing, from the base of the neck to the skull. Contrast is used more readily here than for the arteries inside the head, because the neck is where the injection-free technique struggles most: the vessels run straight through the slices being imaged, and flow immediately past a narrowing is fast and disordered, both of which can make a narrowing look worse than it is. Filling the arteries with dye and photographing them as it passes gives a cleaner picture of the actual channel.

Why it is done

• To look for narrowing from plaque in the carotid arteries, usually after a stroke or a transient ischemic attack, or when a bruit is heard in the neck
• To look for a tear in the wall of a carotid or vertebral artery, a cause of stroke in younger people that often follows neck trauma
• To check the vertebral arteries in someone with dizziness or symptoms arising from the back of the brain
• To assess the neck vessels before surgery or a stent in that region, and to check them afterward
• To trace the blood supply of a mass in the neck

What to expect

Metal screening comes first, then an IV in the arm, and most centers check kidney function before gadolinium is given. Swallowing is the main practical challenge in this exam: the neck moves every time you swallow, and the sequences that matter are short and timed to the dye arriving, so you will be asked to keep still and avoid swallowing for stretches of twenty or thirty seconds. Shoulders stay down, the head stays straight. The neck portion alone takes roughly fifteen to thirty minutes, though the appointment is usually longer because head imaging is often booked with it. You can eat, drive and carry on as normal afterward.

Questions worth asking

• Head and neck MRA are two different codes. Ask exactly which regions the order covers and get each one priced.
• Carotid ultrasound and CT angiography answer many of the same questions at very different prices. Ask what was considered and why this was chosen.
• Ask whether the gadolinium is billed separately, and whether a kidney blood test is being added as its own lab charge.
• Prior authorization for vessel imaging is usually region-specific. Confirm the approval names the neck, not just the brain.
• If this follows an emergency department visit, ask whether the scan will be billed under the hospital's outpatient rate or its emergency rate — they are not the same.