By Michelle Fabiani, DVM, DACVR
A radiograph can quickly become an expensive and a dangerous waste of time (think of that X-ray exposure!) if it’s not showing what is needed. Here are some tips to make you a pro.
The lights in my office are off—the room dark the way I like it. The barks, meows and other various noises of our busy practice are hushed outside my closed door, which prevents interruption of my structured evaluation of each film. I search every pixel of my two black-and-white, high-definition medical-grade monitors. I’m intent on finding the cause of this patient’s breathing difficulties.
Even though I will review radiographs on 25,000 patients this year, this one is exceptionally challenging. There’s an entire portion of the lung field that’s all black. This area lacks information, as it is burned through. I need to see what’s not possible to visualize. I don’t have the needed information to obtain a diagnosis for this sick patient. I sigh. I cannot help this one this time.
With the benefit of high-quality images, a teleradiologist can help obtain an accurate diagnosis and improve the well-being of patients all over the globe, including those at your practice. I’ve worked in both general and emergency practices. I understand you’re busy! Almost every veterinarian and veterinary staff member I’ve ever met is empathetic and caring and wants to do what is best for the pet.
Most days I know it feels like you are running back and forth all day without a single second to do even one more thing. Your technician takes the radiograph of Fluffy you ask for. You look at the films and decide you want a consult. A history is necessary. The technician sees that Fluffy came in for coughing. The tech knows you’re busy and doesn’t want to bother you with one more question, so the tech puts “coughing” down for history and off the consult goes. You feel a little victory and think, Great, now that the radiographs are submitted, I’ll know what is going on by the end of the day! But sometimes teleradiologistis can’t help with limited history such as “coughing.”
I like to say that general practitioners know information that is a mile wide—spanning several animal species, breeds and diseases. Conversely, I know information specific to radiology that is only an inch wide—but it’s a mile deep. As a radiologist, all I do all day, every day is imaging. All of my journal reading and continuing education meetings involve what is new in imaging. What’s the best modality to diagnose a disease? How sensitive and specific is that diagnosis? How can diagnostic imaging techniques help our patients? As a result, radiologists’ understanding of what diseases look like is vast and helpful, but only if we’re provided high-quality images and high-quality supporting information.
That’s why taking time to support better understanding of effective radiology practices is imperative, and improves the diagnostic quality of every imaging study performed in the future. In doing so, we ensure greater accuracy in diagnoses and further support the well-being of our patients. Below are seven techniques veterinarians and technicians can use to take better images today.
1. No mystery in history
One challenge of working as a teleradiologist is that I never see my patients in person. Without physically examining them, being familiar with their history and talking to the owner, quite a bit of background can be lost. It’s critical for whomever is taking and sending the radiographs, whether veterinarian or technician, to provide context that can help my assessment.
One practice we’ve implemented in our hospital is for the veterinarian to fill out the physical exam and history sections, thus providing more detail and nuance that can be quickly relayed to a technician or read from the presenting complaint in the chart. Our doctors also copy and paste pertinent parts of the electronic medical record into the radiology consult, relaying additional information to the radiologist.
Succinct but thorough information, coupled with our understanding of breed- and-age-related diseases, can help tailor a thought process in order to arrive at a more accurate diagnosis. Otherwise, I won’t know the “coughing,” 20-lb, mixed breed is actually an obese, 12-year-old Yorkie that lives in a house with a chain smoker, reeks of smoke and never goes outside. That kind of information changes how helpful a teleradiologist is to you.
2. Collimate and compare
It seems obvious, but before taking a radiograph it’s important to know what you’re looking at and where you’re looking. For instance, when evaluating a patient with lameness, an examination should further direct you to a localized area like the hip, stifle joint or foot. Radiographs should then be focused only on this area, with the remaining areas collimated out of the primary radiographic beam.
The benefit to collimating—focusing in on a single region of the patient’s body is to improve the image quality of that region (Figures 1 and 2). There are only so many pixels on a digital radiograph plate. If the majority of the radiograph isn’t really part of the area that you’re interested in (for instance, taking a whole-body radiograph for a stifle lameness), then as a result, the majority of the pixels are useless. The actual area of interest doesn’t have enough resolution to evaluate adequately.
How can you tell if this is happening on your images? Magnify to the region of interest and see if you notice a pixelated appearance. Collimating provides better image resolution and greater ability to accurately diagnose, resulting in better patient outcomes.
Additionally, most of our patients have a conveniently accessible normal leg that we can use for comparison. If the left elbow is where the pain is localised, you should also take an image of the right elbow so we have an idea of what this patient’s normal looks like. And remember you should always take images in orthogonal pairs—both a lateral and a cranial to caudal—of the affected and the normal leg. For most diagnostic images, you should be taking separate radiographs of each leg—that is, don’t take both elbows in one lateral view nor both elbows in one cranial to caudal view.
3. Wanna be sedated?
At some point, we’ve all dealt with an angry cat whose claws create havoc in the clinic. Or a dog whose long limbs flailed on an imaging table. Their fear-based response to an exam or procedure can harm themselves and staff alike. In this excited state, the chances of taking an image that is useful in making a diagnosis are low, and you’ve charged the client for an unnecessary procedure as well as irradiated the staff unnecessarily.
As part of our initiative to provide better patient care at our specialty clinic, we’re becoming a Fear Free hospital. We take patient stress, pain and fear seriously. Sedation is standard for all patient imaging in Fear Free hospitals—not only radiographs, but all other imaging as well. Our goal is to make the entire patient visit (including imaging) a positive, calm, stress-free event, which ultimately makes the process safer for our staff and also increases the quality of images obtained.
Through sedation, we both assure patient safety and our ability to take the diagnostic images necessary to support treatment of the patient. Sedation also decreases radiation exposure to our staff because those images we do take are of the necessary quality and don’t need to be repeated multiple times. For us, sedation is better for the patient and the staff—and it’s better medicine.
4. Don’t take it easy
Many images I see are taken from what I’d call the “easy” perspective, with the patient laying on its side—that is, a lateral view. Taking a single view from that position is one of the biggest ways to miss pathology. Taking two images (one with the patient on their side and the other with the patient on their back) should be standard for every patient and is always worth the effort for the significant amount of diagnostic return on investment. Because most of our patients are skinny, ventrodorsal images can be taken more easily with the help of a soft, padded, V-shaped trough. These are inexpensive, easy to clean positioning devices that help the patient lie both comfortably and still on their back for the duration of the imaging study.
5. A snapshot versus a photograph
I work closely with both general practices as well as my radiology technicians, educating them about how to obtain a high-quality radiograph. For those individuals who haven’t received appropriate training, they may assume that if the patient’s in the radiograph, it’s also of adequate diagnostic quality. This is not their fault—it’s simply lack of training! In order to support understanding of a quality radiograph, I teach technicians and veterinarians objective criteria that can be easily utilised while obtaining the images.
For thoracic radiographs, the position of the retrosternal lucency and the lumbodiaphragmatic recess during inspiration can be counted and compared to rib position. It’s easy to count the vertebrae compared to the position of the diaphragmatic cupola and the costodiaphragmatic recess as well. How do I know if the ventrodorsal radiograph is straight? Look to see if the sternum is on top of the vertebrae. Providing specific, objective criteria will help everyone assess the quality of their own images while the patient’s still on the imaging table and helps determine if the radiograph needs to be taken again.
Anyone can take a snapshot on their phone. It takes a lot of training, practice and understanding to actually be a photographer. This is the difference between someone who can take a radiograph by pushing the expose button and someone who can take a good quality diagnostic radiograph. Training results in expertise, which in the end is an exceptional value for the patient and practice.
6. It’s all in the timing
Haven’t we always heard, “it’s all about timing”? That adage is definitely true in radiology. An image of the thorax should be taken during inspiration, when the lungs are completely inflated. Conversely, the ideal time to take an abdominal radiograph is at complete expiration, when the lungs are the smallest. When the lungs are halfway between inflation and expiration, you’re taking a poor image of both areas. When an x-ray machine salesman says that a single whole-body radiograph can be taken versus taking a collimated radiograph of either the thorax or abdomen, he’s not telling you what is best practice or most diagnostic. He hasn’t gone to veterinary school, nor is he a radiologist. Remember, just because you can do something doesn’t mean you should. When you collimate, focusing on a specific region of the body with the appropriate image timing, you do the best for your patients and your clients.
7. Marker my words (and images)
Many practices have grown accustomed to using digitised right or left markers, added to the image after it is taken. Unfortunately, sometimes those digital markers don’t transfer when images are sent to the radiologist. The result? Time-consuming phone calls to discuss what images were obtained. This can ultimately end in the teleradiologist not knowing left from right, thus limiting the ability to obtain a useful diagnosis.
We encourage the use of an actual physical lead marker placed in the primary radiographic beam on every image. Markers are a quick and inexpensive solution that supports the accurate interpretation of images by a teleradiologist.
Now it’s time to put these tips to work!
Using the above helpful techniques will help us radiologists help you. This will ultimately help all your patients. After all, isn’t that why we all got into the veterinary field? Happy imaging!