A Brief History of Radiologic Time
Articles on veterinary radiology began appearing as long ago as 1896, just one year after the discovery of the x-ray. But for decades after that, “judging from the photographs of veterinary radiographic attempts…it seems likely that more harm was done to the radiographer’s assistant than there was good done to the patient,” said Gerry B. Schnelle, VMD, at the First International Conference of Veterinary Radiologists in Dublin in 1968. It hadn’t become clear yet just how damaging repeated exposure to x-rays could be, and assistants’ hands were often caught by the x-ray beam. “Even as late as 1953,” Dr. Shnelle said, “when a veterinary lecturer from central Europe…was questioned about slides showing his assistant’s hands in the direct beam, he replied to the effect that assistants were replaceable!” By the 1960s, however, x-rays of pets were being taken without harm to veterinary staff.
The first wave of ultrasound in veterinary medicine began in university settings in the late 1970s and early 1980s but didn’t start to become mainstream till at least a decade later. “The 90s were the big adoption period” for ultrasound scanners in veterinary medicine, says Tufts veterinary radiologist James Sutherland-Smith. Today, “if your dog’s veterinary practice is a large one, you’ll probably find an ultrasound machine there.” Otherwise, referral to a practice that has ultrasound on the premises generally won’t send you hundreds of miles out of your way.
Veterinary CT scans have a timeline similar to that of ultrasounds. The first CT scans were used in human medicine in 1971, then began making their way into animal medicine in an experimental way about 10 years later. “It came into the mainstream in the 90s,” Dr. Sutherland-Smith says. You won’t usually find a CT scanner at a general practice clinic, but “most referral centers have them,” he points out.
MRI machines were first used to help diagnose problems in humans in 1977, but “dogs were being snuck into human MRI facilities as late as the mid 90s,” Dr. Sutherland-Smith reports. “Then veterinary hospitals started getting their own. We purchased ours at Tufts in 2006. Prior to that, we rented a trailer unit.”
Nuclear medicine has been around a little longer — Tufts has had its nuclear medicine apparatus since our animal hospital opened in the 1970s. But nuclear medicine facilities for animals are still rare — “usually limited to university veterinary hospitals,” Dr. Sutherland-Smith says, “so few dogs get this type of diagnostic imaging. There may be only one other nuclear medicine machine in all of New England that serves dogs, although others serve horses.”