Excelling at X-rays: Why What You May Not Know About Radiography Might Hurt Your Pet
Posted May 10 2011 7:00am
Ever wondered at how it is veterinarians look at all those black and white images in grayscale 2-D and somehow manage to make them mean something? I do. All the time.
It’s not that I don’t read X-rays all the time. I do. It’s part of my everyday job. However, I’m also acutely aware of the fact that those who are uniquely trained to interpret these images full-time are much better at it than I am.
Makes sense, right? It’s why we use veterinary surgeons, internists, cardiologists, ophthalmologists and more. In fact, human medicine has taken specialization to practical extremes after recognizing that while practice may not make perfect, it definitely makes doctors better. And better is what most of you want when it comes to your pets’ health.
Well, mostly. Because better almost always means it’s more expensive, too. And more expensive can be impossible for some of us. Still, it’s a definite trend
These days, veterinarians are taking better pictures of your pets than ever before. They’re using higher quality digital equipment that not only renders images intrinsically more readable, it makes sending pics to veterinary radiologists a snap.
This is one of the reasons why the field of veterinary radiology has taken off so quickly. Because now that we can get a radiologist’s expert opinion in under an hour if need be, many of us are choosing to do so; frequently, and even routinely.
The other reason has to do with what YOU, our clients, are clamoring for — namely, better results. And to get better results, experts of all stripes will need to be brought to bear. That’s inevitable. That is, if you accept my initial assessment that specialists bring you better medicine.
I’ll even go one further: Judiciously applied, specialists bring you cost effective veterinary medicine. And nowhere is this increasingly more obvious than with respect to the hyper-accessible veterinary radiologist. With ready speed of transfer, larger volumes of digitized files are eligible for big discounts, which mean that many veterinarians are starting to outsource every single X-ray they take to radiologists.
In my view, that’s not a bad idea at all. Consider last week’s feline patient: She came in for the super-common lower urinary tract issues so many cats suffer. So she got an X-ray of her abdomen to search for stones and other obvious lesions. But a sliver of her chest got into the pic. And that heart looked a little big on one side. So let’s see what the radiologist says
Can you say pericardial peritoneal diaphragmatic hernia? We can’t either. That’s why we call it a PPDH. And it’s not something I would have known to diagnose on those X-rays in the absence of any clinical signs. But it might just explain why, on further questioning of the owner, intermittent projectile vomiting and small-bowel diarrhea has become an episodic issue with her (you’d think people would mention these things, but they often don’t). So she’s on her way to see the surgeon (another specialist I can’t live without).
Three years ago I would’ve had to wait for snail mail to send my rads out to the local radiologist. Or, more commonly, I would’ve been trucking pics over to the specialist’s place for a second opinion. But nothing’s as easy as paying an extra $25 for pushing a button and getting a detailed written report within 24 hours.
But is it really better? I mean, when a veterinarian’s been reading X-rays the whole of her working life, how much better can one of those newbie board-certified radiologists be? Um … much … especially where it counts.
Just in case you doubt, there is research to show that veterinarians who get boarded in radiology are better at identifying things like pulmonary nodules. A recent research study, published in the April 15th JAVMA, quantified how much better. Experienced veterinary general practitioners and board-certified radiologists were shown 114 images in two different display modes (regular and inverted) and asked to interpret them at two separate points in time.
Detection accuracy for board-certified radiologists was significantly greater than that of veterinary general practitioners for both display modes. Near-perfect intra-observer agreement was detected between the 2 display modes for board-certified radiologists, whereas moderate to slight intraobserver agreement was detected for veterinary general practitioners.
In other words, not only were the generalists not as good at reading the films, they were less accurate, failing to agree with themselves the second time they interpreted the images.
This really shouldn’t make you want to doubt your generalist in most cases. After all, pulmonary nodules can be a tough case for anyone. Still, it should make you wonder, and perhaps even prompt you to ask your veterinarian: "Do you think a board-certified radiologists should take a look at those films?"