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Jonathan Hayles

Dr. Jonathan Hayles
Veterinary Specialist
Diagnostic Imaging
Dr. Jonathan Hayles

Dr. Hayles is a long time San Diego resident, completing a Bachelor of Science at UC San Diego in Animal Physiology and Neuroscience in 2000. He completed the DVM program at UC Davis in 2006.

Dr. Hayles then pursued a competitive one-year rotating small animal internship at the Veterinary Medical and Surgical Group (VMSG) in Ventura, CA. Directly following his internship, Dr. Hayles began the radiology residency program at Washington State University (WSU) College of Veterinary Medicine. His training in diagnostic imaging included small and large animal diagnostic ultrasound, radiography, magnetic resonance imaging (MRI), computed tomography (CT), fluoroscopy and nuclear scintigraphy. Concurrently, Dr. Hayles earned a Masters in Veterinary Science (MS) degree, with research focusing on abdominal MRI and correlations to abdominal ultrasound; specifically regarding adrenal gland anatomy.

In 2010, Dr. Hayles successfully completed the certifying ACVR examination. After several months remaining at WSU as a clinical instructor, Dr. Hayles and his wife, Andrea, returned to San Diego.

When not working, Dr. Hayles enjoys surfing, ultimate Frisbee, travelling and spending time with his wife, two sons, Alexander and Andrew (Drew), his dog (Charles Jr.) and cat (Bali).

See our departments

Diagnostic Imaging

Great veterinary vision for pets. Great medical insight for veterinarians.

Diagnostic Imaging (radiology) refers to using different non-invasive technologies to acquire images in order to help make a diagnosis. A variety of advanced imaging machines and techniques, including digital radiography, CT scanning, MRI, and ultrasound are used at ASG to examine and evaluate different structures within your dog or cat’s body.

Our radiologists works closely with our team of specialists to determine the most appropriate imaging modality and to interpret the results of those images to assist in diagnosis or to guide other therapy.

Imaging + Interpretation are now available on an outpatient basis.

There may come a time when your family veterinarian needs an advanced imaging study, such as contrast radiography, ultrasound, fluoroscopy, computed tomography (CT scan), or magnetic resonance imaging (MRI), to complete your pet’s diagnostic puzzle. While many practices have ultrasound, most do not have color-Doppler, and very few have fluoroscopy, CT or MRI, for good reasons – these machines are expensive, they take up a large amount of space, they bring additional regulatory requirements and they just are not needed very often in day-to-day general medicine.

Shared access to advanced technology is part of what drives specialization. ASG has these technologies at our disposal, and we offer their use on an out-patient basis. If your pet needs an advanced imaging study, your veterinarian can make a referral, and we will schedule an appointment.

The best radiograph, ultrasound image, CT scan or MRI image is completely without merit if it is interpreted, or read, incorrectly. Reading advanced images has been likened to speaking a foreign language – “if you don’t use it, you lose it.” That is why we have extensively trained radiologists to interpret these images. Their experience, along with the fact that they work with these images every day, make their interpretation priceless. They personally examine and interpret every image, and send a detailed report to your veterinarian.

Imaging modalities 101

Contrast studies: Contrast radiography involves the use of a dye that is visible on radiographs to outline a specific structure. While most veterinarians are comfortable using oral barium for this purpose to get more information about the stomach and intestines (and possible obstructions), many are not comfortable performing or, more importantly, interpreting the results of other advanced contrast studies. Injecting dye into joints or around the spinal cord is not something that most veterinarians need (or want) to do on a daily basis, but our radiologists perform these procedures routinely.

Fluoroscopy: Fluoroscopy is to radiography what movies are to photographs. The same basic concept, put into motion. Fluoroscopy is used to display movement, and can be used in blood flow studies (using dye), or other areas where change over time is important, such as collapsing trachea, which may or may not be visible with plain radiographs.

Ultrasound and color Doppler: Diagnostic ultrasound has come a long way from its ship’s sonar roots. Ultrasound uses sound waves to create images of structures within the body, and can even guide a biopsy needle to the precise spot for more accurate sampling. Color Doppler is generally used for echocardiography, ultrasound studies of the heart. Blood flowing in different directions shows up as different colors on the screen, and turbulent blood flow (which should not be present) can be clearly visualized.

Computed tomography (CT) scans: CAT, now generally referred to as CT, has nothing to do with cats (although cats do get CT scans). Computed tomography is a technology that utilizes computers to extract the data from multiple digital radiographs, and create 3D images of “slices” through the body, through different planes and different angles. CT is an excellent way to visualize organs, blood vessels, or masses and their relation to other nearby structures.

Magnetic resonance imaging (MRI): MRI uses a very large magnetic field, to align all of the molecules in the body in a certain direction. When a magnetic pulse is applied, all of the molecules move in a certain, predictable way, yielding an image that is almost photographic. Although MRI does not image bony structures as well as CT, it does provide a much higher detail of soft tissue structures, like the brain, heart, lungs, and abdominal organs.

Imaging Services

  • CT Angiography
  • Digital Radiography
  • Fluoroscopy
  • Gastrointestinal Contrast Studies
  • Digital Ultrasonography with Color-Flow Doppler + Tissue Harmonics

Imaging Equipment

  • Ultrasound (color Doppler)
  • Digital and Mobile Radiography
  • Fluoroscopy
  • Magnetic Resonance Imaging (MRI)
  • Spiral Computed Tomography (CT scan)

Our Diagnostic Imaging Team

Registered Veterinary Technician
VCA Animal Specialty Group

5610 Kearny Mesa Rd., Suite B

San Diego, CA 92111

Main: 858-560-8006, Fax: 858-560-0206

Fax: 858-560-0206

Hospital Hours:

    Mon: 7:45 am - 12:00 am

    Tue-Fri: Open 24 hours

    Sat-Sun: Temporarily Closed

E-fax: 310-442-4548
Email: [email protected]

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