This research article follows the mould of several ultrasound research papers lately: you take a group of physicians, give them a short, focused course on doing a new ultrasound procedure and then check if this basic skill teaching can give a clinical advantage. And in this case, it could. After learning what to look for, these docs used ultrasound to look at young patients with a suspected skull fracture that had already gotten ordered the gold standard – and high radiation – CT scan.
In 69 patients with suspected skull fracture, 17 actually had a fracture on CT. Ultrasound found 16. With these small numbers, this racks the sensitivity of ultrasound down to 88% compared to CT in this article. 88% might sound pretty good in some settings, but not when we’re talking about skull fractures and not when you have something better.
So, let’s look at the numbers in this article: The one fracture they missed was a fracture not directly underneath the hematoma, but adjacent to it. This one miss points out a key feature with ultrasound: you can only see what you point the probe at. When the probe was placed above the fracture site, the fracture was easily identifiable in all cases. So with ultrasound, you have to go over the suspected area very thoroughly and systematic.
As most of these teaching-and-using-ultrasound articles, this was a small sample article. With this in mind, like other articles looking at ultrasound for fracture identification, this one also finds ultrasound to be a very good tool. I would certainly like to implement it for suspected skull fractures – before CT.
This small article can certainly not be used to change practice, but it points out a possible use of US that deserves attention. In the everyday ED it’s always a balance that will need clinical judgement: certain radiation vs possible fracture.
I could think of selected cases where I’m already leaning away from CT, and a scan by a seasoned ultrasonographer could be another argument tipping the scales in favour of clinical examination combined with ultrasound – and no CT. Thoughts?