Skull X-ray (1 to 3 views)

What it is

A skull x-ray is a picture of the bony shell around the brain, taken from one to three angles. It is one of the oldest tests in medicine and it has been largely displaced for its most obvious use: after a head injury or when a brain problem is suspected, a CT of the head is usually preferred, because it shows both bone and the tissue underneath while an x-ray shows only the outer casing. What remains of the skull x-ray's role is narrower — questions about the bones themselves, about the shape of a child's head, about the sinuses and the mastoid air cells behind the ear, or about something dense lodged where it should not be.

Why it is done

• To look at the skull bones for fractures, erosion, or abnormal growths
• To examine the shape of an unusually formed head in an infant or young child
• To look at the sinuses or at the bone behind the ear in suspected infection there
• To check the position of a plate, a shunt, or another implanted device in or near the skull

What to expect

The patient sits in a chair or lies on the table while the technologist turns the head into each position — straight on, in profile, sometimes tipped back — and steadies it, then steps away for each brief exposure. Glasses, earrings, hairpins and dental appliances come out first. Nothing is felt. The whole thing takes a few minutes. The awkward part is holding the head in an unfamiliar position, which is harder after an injury or for a restless child; parents are sometimes asked to help hold a small child still. A radiologist reads the images and sends a report.

Questions worth asking

• Is a CT of the head likely to be needed anyway? If so, ask whether the x-ray is a step toward it or a cost that will be repeated.
• Does the order say fewer than four views? A larger series is a different code at a different price.
• If the question is really about the sinuses or the ear, is a dedicated study of that region the right exam, and is it priced differently here?
• Was this taken in an emergency department? Ask whether the imaging charge is separate from the visit-level facility charge on the same bill.