Sharing Mayo Clinic: Specialized imaging and targeted brain surgery for epilepsy

Sharing Mayo Clinic: Specialized imaging and targeted brain surgery for epilepsy

By
Dana Sparks

July 21, 2019

There was a time when Gavin Vreeland was afraid he might hurt his daughter should he have a seizure while caring for her. Despite taking medication, his epileptic episodes happened frequently and without warning. But after specialized imaging and targeted brain surgery at Mayo Clinic, Gavin is now happily embracing his little one seizure-free.

Gavin Vreeland was fed up. For more than 11 years, the resident of Kahoka, Missouri, lived with alarming seizures that stopped him in his tracks. The seizures caused his lips to smack, his eyes to glaze over and his hands to tighten their grip. More often than not, he'd black out.

Numerous physicians agreed Gavin's seizures were epileptic, but the source of the abnormal activity remained a mystery despite multiple MRI scans of his brain. Gavin took dozens of pills a day to control the episodes, but the seizures continued.

Not only was Gavin frustrated by the lack of improvement in his seizure activity, so was his hometown neurologist. "We were tired of trying a bunch of medications, and he finally said: 'Let's change things. I'm going to recommend you to Mayo Clinic,'" Gavin says.

In February 2018, Gavin met neurologist Jeffrey Britton, M.D., at Mayo Clinic's Rochester campus. Dr. Britton recommended Gavin undergo a specialized MRI scan to learn more about his condition. Gavin's care team used the MRI images to identify a defect in his brain, known as a temporal lobe encephalocele, as the cause of the seizures. A month later, Gavin underwent brain surgery during which Mayo Clinic neurosurgeon Jamie Van Gompel, M.D., removed the encephalocele.

Now more than a year later, Gavin hasn't had any seizures since his operation. He's reduced his medications. He's back to work and happy to be living life without worrying about being hit by a seizure.

"My life has changed by my stress level going down quite a bit just knowing I am going to be able to wake up, and I can decrease my medications, and I finally don't have to deal with seizures anymore," Gavin says.

Disruptive disorder

Gavin's first seizure occurred when he was a 22-year-old college student. When it struck, the seizure hit hard, Gavin says. "I sat down in a recliner and started watching TV, and the next thing I knew, I was waking up in the back of an ambulance going to the hospital."

That grand mal seizure resulted in Gavin being diagnosed with epilepsy and prescribed an antiseizure medication. As the years passed and Gavin continued to experience seizures, he tried a number of new medications. Although a new drug would stop the seizures for a time, they always came back.

"I'd go maybe two to three weeks and then, bam, I'd have a small episode," Gavin says. "It would last maybe 10 to 15 seconds, and I'd have two to three episodes right after that."

"I never had any warning signs that I was about to take a roller coaster."
Gavin Vreeland

During his seizures, Gavin would stare blankly into "la-la land," he says. "I'd smack my lips and saliva would come out of the side of my mouth. I'd start twirling my hands. My grip would tighten. One time I had a full soda can in my hand and began to have an episode, and I literally crushed the soda can with my hand."

The events were unpredictable. Once, a seizure stuck while Gavin was working in a restaurant. He passed out, hit his head and required several stitches. "I never had any warning signs that I was about to take a roller coaster," he recalls.

As is the case with 1 out of 3 people in the U.S. with epilepsy, Gavin had what's known as drug-resistant epilepsy, Dr. Britton says. "Despite medication therapy, they continue to have seizures."

In some cases, surgery may be an option to treat this form of epilepsy but not always. "When we see people with drug-resistant epilepsy, not all of them are able to be operated on for their epilepsy," Dr. Britton says. "For surgery to be an option, first there needs to be one source."

If a single source or location within the brain can identified as the cause of seizures, the next factor to consider for surgery is whether that part of the brain can be safely removed.

In Gavin's case, the fact that his seizures were consistently similar to one another increased the likelihood that they were coming from one source. That made surgery a possibility, but he'd need careful evaluation before his team could move forward.

Answers at last

Because the source of Gavin's seizures was unknown when he and his wife, Kristy, arrived at Mayo Clinic, his care team decided to take a more detailed look using specialized imaging. Gavin underwent an epilepsy protocol MRI, so his care team could look at his brain's temporal lobe using particular sequences that can help identify encephaloceles.

The first specialist to read Gavin's scans was neuroradiologist Carrie Carr, M.D., in the Department of Radiology. Dr. Carr saw what she thought looked like an encephalocele, and she shared that finding with the neuroradiology team. The MRI was followed by a high-resolution CT scan that evaluated the skull base for abnormal holes. That test also showed the presence of an encephalocele, which was confirmed by radiologist Greta Liebo, M.D.

"Encephaloceles result from defects at the base of the skull," says Robert Watson Jr., M.D., Ph.D., chair of the Division of Neuroradiology. "Essentially, little holes in the bone permit the adjacent brain to protrude through it, stretching and irritating the tissue, and that can set off epileptic seizures."

It's only been within the past few years that the medical community has recognized encephaloceles can cause seizures, Dr. Watson says, adding that at Mayo Clinic, Dr. Van Gompel has been a leader in recognizing the importance of carefully evaluating MRIs and CTs for these subtle findings. "As a result, we've come up with specialized sequences in MRI to be more sensitive to find these," Dr. Watson says. "And we've developed a detailed CT protocol to get very fine cuts of the skull base to identify them."

"The beauty of the surgical epilepsy conference is that we all get together in a room — the neurologist, the neurosurgeon and the neuroradiologist — and we discuss these challenging patients to make a decision about whether surgery will help their epilepsy."
Robert Watson Jr., M.D., Ph.D.

In addition to Drs. Carr, Liebo and Watson reviewing Gavin's imaging, five other Mayo neuroradiologists looked at the scans and provided input before Dr. Watson presented Gavin's case at a Mayo Clinic surgical conference in March 2018.

"The beauty of the surgical epilepsy conference is that we all get together in a room — the neurologist, the neurosurgeon and the neuroradiologist — and we discuss these challenging patients to make a decision about whether surgery will help their epilepsy," Dr. Watson says. "In the conference, we correlate the imaging findings and EEG to try to identify the seizure focus and decide whether surgery is possible."

Along with the sequenced MRI and CT scan, Gavin received an extended EEG to better measure the encephalocele's location in his brain. To conduct the test, Gavin was hospitalized and electrodes were attached to his skull. His medications were decreased slowly. As he was weaned off antiseizure drugs, his team waited for him to have a seizure. It took 12 days.

Unlike most of his seizures, when that one hit, it was a welcome relief. "I only remember slowly coming to," Gavin says of waking up after the seizure in the hospital. "I reached above me, and I didn't feel the wires. I looked at Kristy and asked if they finally got something, and she said, 'Oh yeah.' I could see it happened by the look in my wife's eyes."

Precision surgery

Based on the findings from his evaluation, Gavin's care team recommended surgery. In mid-March 2018, Gavin underwent the operation to remove the encephalocele. Because Gavin's lesion was in his left temporal lobe, surgery to remove the tissue presented a risk of affecting his memory and speech, among other issues, Dr. Van Gompel says.

"'If we were to take the same approach to epilepsy surgery on the left side as we do on the right side and take out the same amount of tissue, that has been known to cause a lot of problems with verbal memory and other issues. Some patients are really devastated by that procedure," Dr. Van Gompel says. "It makes the left side very difficult to treat. We look at the left side a lot differently than the right side."

In Gavin's case, Dr. Van Gompel focused his attention on the encephalocele and took out as little tissue as possible. "We did the most limited surgery first to see if it was successful and if not, plan B was to do a full temporal lobectomy," Dr. Britton says.

During the approximately three-hour procedure, Dr. Van Gompel took out the encephalocele as well as neighboring brain tissue. In place of the brain tissue he removed, Dr. Van Gompel placed a small piece of fat taken from Gavin's belly.

Finally seizure-free

Gavin remained in the hospital for nearly a week after surgery. Then, several weeks later, he returned to his local neurologist and, under his care, slowly began decreasing his medications one pill at a time.

"It's amazing when you go down from 30 pills to eight," Gavin says. "I don't know if there's a chance that I'll be off medications one day, but there's a shot. But if not, I've hit a big goal that I'm appreciative of."

"Gavin's passed a year threshold, which is a nice milestone, and I think things are looking very favorable."
Jeffrey Britton, M.D.

Because there is no way to predict how patients will do after brain surgery, each patient's treatment following the procedure is different. "There are a number of factors that go into a decision about whether you attempt to stop the medication or not," Dr. Britton says. "Some people do well for a while, and then start to break through. Usually if they make it past a year without a seizure, the chances of relapsing are quite a bit less. Gavin's passed a year threshold, which is a nice milestone, and I think things are looking very favorable."

Gavin says the last seizure he experienced was the one during his February 2018 hospitalization. "My wife still gets kind of nervous if she hears something drop in the house or, by some chance, she hears me smacking my lips," Gavin says. "But since surgery, I've not had one episode, and God willing, let's keep that going."

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