Veterinary Radiologist Performs Laser Disc Ablation Surgery At Oklahoma State University

Seven needles, four minutes of laser energy, and voila — dogs can kiss repeat disc herniation goodbye.

A veterinary radiologist in Oklahoma says the laser surgery prevents recurrence of disc herniation and gives dogs a reprieve from back pain. In essence, it vaporizes problematic discs and facilitates natural fibrosis in dogs of all ages, said Robert Bahr, DVM, DACVR, who operates on dogs at Oklahoma State University (OSU). People from all over the United States have taken dogs to the teaching hospital for the surgery. 

The procedure, which is also done in human medicine, functionally fuses vertebrae, which may limit mobility of the spine. The end result, however, enables dogs once hobbled by back pain to walk, run, and jump, Bahr said. Although cats experience degenerative disc disease, veterinarians rarely see recognizable clinical signs.

The key to success lies in the hands of pet owners and private practitioners, who can identify signs of back pain early. If medical or surgical treatment is initiated early, discs can be decompressed before herniation causes irreparable damage, Bahr said.

Small dogs (weighing up to 25 pounds) are most likely to experience this type of disc degeneration disease, which causes repeat disc herniation.

Symptoms of the disease range from behavior changes and inappetence to limping and paralysis. The severity and onset of symptoms indicate the force with which gelatinous disc fluid is expelled into the spinal canal, which influences recovery predictions, Bahr said.

First tested in 1993 on organ tissues and canine cadaver spines and discs, laser disc ablation has been performed on hundreds of client-owned dogs with positive results. Most of the dogs that undergo surgery are kept overnight and sent home with three days worth of nonsteroidal anti-inflammatory drugs, though Bar said most patients can walk by the end of the first day and are pain-free within two days.

“The pain is minor,” he said, referring to the insertion of needles into muscles. “It is just minor soreness, which resolves very quickly.

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Once a dog has an episode of disc herniation, it is a candidate for the surgery; however, Bahr insists that a full recovery is essential before the laser is used. Initially, dogs can be treated medically with corticosteroids or surgically but several months should pass before laser disc ablation is attempted.

If any residual inflammation is present, the laser can cause more damage to the spinal cord by pushing discs out further, Bahr explained.

He added, "the majority of work is the placement of the needles,” which requires fluoroscopy to ensure accuracy. Needles must penetrate skin and muscle so that the tips reach into the spine. Prior to needle placement, doctors take radiographs to rule out spinal tumors, fractures or congenital anomalies.

From start to finish, the surgery takes about an hour and entails placement of seven needles along the vertebrae. Once needles are placed into the discs, doctors thread laser fibers into the needles and apply two watts of laser energy for 40 seconds to each disc. Once vaporized, discs turn into a black, oily material called char—some of which is extracted through the needle. Inflammation from residual disc material remaining in the disc space attracts defender cells, which remove char and call in fibroblasts to produce scar tissue. A video of the procedure, which was provided by OSU, is available on the Trends online website.

In some cases, radiographs show that the ends of the vertebrae (where the disc used to be) have grown closer together. The laser ablation is an alternative to surgical disc fenestration, a traditional surgery that does have an incidence of herniation recurrence and requires a much longer recovery period, Bahr said.

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