Once a specialty diagnostic with limited use in the veterinary field, ultrasound has evolved into a widely accepted—and expected—standard of care.
John Feleciano, DVM, Dipl. ACVR, VDIC manager of radiology with Idexx Laboratories in Clackamas, Ore., says ultrasound no longer is an optional service.
Eric Lindquist, DMV, Dipl. ABVP, the founder and CEO of SonoPath.com, participated in a study of intraoperative ultrasound for precise biopsy and resection of transabdominally detected intestinal lesions in three cats. He explains the ultrasound of the patient, a 14-year-old FS DSH that presented for vomiting and weight loss.
No abnormalities were seen on bloodwork or urinalysis. The intraoperative ultrasound was performed in order to identify the intestinal wall lesion seen during the transabdominal sonogram. The intestinal lesion could not be seen by the surgeon on exploratory laparotomy given that the intestinal serosa was not involved in the pathological process, but the intestinal wall was focally infiltrated with lymphoma.
Moreover, the extent of the lesion could not be seen either unless it was defined by the ultrasound image. Ultrasound allowed for adequate resection of the lesion since the clinical sonographer could delineate the infiltrative neoplastic pattern to the surgeon and hence, resect the entire lesion.
The patient is asymptomatic three years post-op on a protocol for inflammatory bowel disease that was concurrently found on intestinal biopsies elsewhere in the bowel.
“Most clinics either have access to a radiologist, internist or sonographer, or have a machine that they use at their clinic,” he says. “Clients often demand this higher level of medicine.”
In today’s modern veterinary practice, ultrasound has ascended to nearly the same importance as radiograph devices, says Guy Hammond, president of VetImaging in Irvine, Calif.
“The reality is that radiographs excel at imaging bone and gases, and ultrasound excels at imaging soft tissue and fluid,” he says. “You regularly need both modalities to paint a clearer picture from a differential diagnostic perspective.”
Greg Stoutenburgh, vice president of marketing for Sound-Eklin in Carlsbad, Calif., says abdominal imaging is still the main use for ultrasound.
“However, other uses such as echocardiography, ultrasound-guided procedures, musculoskeletal imaging and ophthalmic scans are in more use every day,” he adds.
Advances in veterinary ultrasound are driving the technology’s increased application. Stoutenburgh says ultrasound image quality has improved tremendously in recent years because of features such as speckle reduction imaging (SRI), harmonics and coded excitation.
“Additionally, technologies such as 3D and real-time 4D imaging are revolutionary,” he says.
Similarly, Randy Laufersky, president of Core Ultrasound in Comstock Park, Mich., says recent advances include automatically enhancing image quality with the push of a button as well as digital probes that operate at various frequencies, reducing the need for multiple probes and reducing the cost barrier to getting into ultrasound.
VetImaging’s Hammond notes that high-quality ultrasound imaging is available in small and highly portable platforms.
“This allows ultrasound to be taken to the patient as opposed to bringing the patient to the ultrasound machine,” he says. “In the clinic, this provides for a level of versatility that makes ultrasound far more available for use as a diagnostic aid.”
Indeed, Mia Varra, marketing director for E.I. Medical Imaging in Loveland, Colo., says that features standard on higher-end cart-based systems are becoming available in portable systems. She says these include field of view, quick zoom, cine loop (eight-second video playback), flash drive image storage, USB link, wireless link, voice tag, track-ball navigation, RFID readers for animal identification, gestation tables and easy caliper measurement.
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The importance of training and practice with veterinary ultrasound cannot be overstated, says Eric Lindquist, DMV, Dipl. ABVP, the founder and CEO of SonoPath.com. In this respect, veterinary clinics have a wide range of options.
Dr. Lindquist recommends the Academy of Veterinary Imaging, courses associated with ultrasound companies and universities such as Ohio State University.
“Scan labs and ultrasound lectures at conferences also help in the process,” he says. “Private instruction is often a valid choice as well, where available. However, in my experience, private instruction is usually more fruitful after some level of formal coursework at one of the venues mentioned above.”
Though an official certification isn’t needed to use an ultrasound machine, Lindquist says attempts are being made to unify an educational platform, with certification for non-radiologists and ultrasound.
“The International Veterinary Ultrasound Society is the best venue that I have seen as part of a certification and validation of a clinical sonographer that adapts to the work flows of the practitioner with online case submission and testing,” he says. Sonographers need to document a series of educational courses completed in ultrasound to qualify for the program.
“This is not a board certification nor is it meant to be one,” Lindquist adds. “But it is an emerging entity that validates the veterinary clinical sonographer’s ability to acquire and interpret sonograms while also supporting a community atmosphere of case exchanges to draw upon the experience of others.”
Despite the lack of formal certifications, John Feleciano, DVM, Dipl. ACVR, of VDIC Inc. in Clackamas, Ore., says practitioners who want desirable results need to undergo extensive training and commit themselves to the learning curve of ultrasound. In this sense, practice is key.
“Scan whenever you can,” Dr. Feleciano says. “Ultrasound is a numbers game. I generally say that when you have performed 100 cases in each cavity, you will begin to feel comfortable.
“One way to accelerate your confidence is to perform fine needle aspirates using a non-aspiration technique on any tissue that is abnormal. Just make sure that you have a pathologist who is very experienced and skilled at reading fine needle biopsies.”
Eric Lindquist, DMV, Dipl. ABVP (canine and feline practice), the director of operations for New Jersey Mobile Associates in Sparta, N.J., and the founder and CEO of SonoPath.com, says veterinary ultrasound has almost completely moved to software upgrades to improve image quality.
“For example, in the past if you wanted to upgrade the image quality in your practice, you had to buy a new machine with a large cost to go with it,” he says. “Now, for most upper-level machines, image quality improvement is largely about upgrading software in a matter of a five-minute upload, just like you would with your home computer.”
Though technological advances have lowered certain cost barriers to entering the ultrasound field, practices still must dedicate time and resources to bring their staffs up to speed on the new modality.
“For the new person starting out on ultrasound, telemedicine is an integral part of their education,” Laufersky says.
Mike Collins, national product manager for ultrasound sales at Vetel Diagnostics in San Luis Obispo, Calif., says veterinarians need to know their ultrasound limitations, whether such limitations are due to their training, experience or the quality of the machine they purchased.
“With very little training and any machine, veterinarians can easily diagnose bladder stones, pregnancies or do cystocentesis,” he says. “The ultrasounding veterinarian should always be aware of when they have reached the limits of their skills and knowledge and ask for a consult, even if it is to only confirm what they believe they have diagnosed.”
Because of advances in ultrasound image capture, Varra says, it is easier than ever to transfer ultrasound images and video clips to specialists. “This allows a practice to be able to utilize radiologists and specialists in emergency or after-hours situations,” she says. “Most telemedicine consultants will specify a list of required scans, by view, that they need in order to perform a specific service.”
Dr. Feleciano says some specialists question whether telemedicine consultations for veterinary ultrasounds have value. “I believe that ultrasounds are getting performed across this country and world every day without a specialist interpreting the images, and conclusions are being drawn from them,” he says. “At VDIC, we believe that we can be helpful in interpreting the images and the cases that are submitted to us.”
That said, Feleciano notes that the amount of information that can be provided from ultrasound images depends on the quality of the study.
“The more skilled the sonographer capturing the images, the more complete the anatomy and pathology that is represented with multiple imaging planes, the more complete the images are labeled, and the more complete the patient is presented clinically in the history, the more helpful and accurate the interpreting radiologist will be,” he says.
This article first appeared in the May 2010 issue of Veterinary Practice News