DIAGNOSTIC IMAGING
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
Figure 1. This lateral radiograph was taken without sedation and
without collimation, significantly limiting interpretation of the
spine. (Photos courtesy of Dr. Michelle Fabiani)
Figure 2. This radiograph was obtained after sedation. Adequate
centering of the radiograph beam and collimation were utilized
allowing for excellent interpretation of the lumbar spine.
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
Issue 03 | JULY 2018 | 21