Trent Johnston worried fans when he received “life-altering” news about his health during an episode of 7 Little Johnstons.

Trent Johnston Revealed His Brain Has Reduced to the Size of an 81-Year-Old

During season 15 of 7 Little Johnstons, which began airing in January 2025, Trent underwent an MRI after experiencing cognitive symptoms such as memory loss and received grim results from his doctors.

“The size of my brain, the diameter, the gap, the spacing between my brain and my skull has reduced at a faster rate than what it should be at 47 years old,” Trent explained during episode 3 as Amber picked him up from his appointment. “It’s the size of, like, an 80, 81-year-old.”

With his brain deteriorating at such a fast rate, Amber worried that would lead to a higher chance of dementia or Alzheimer’s.

In addition, Trent said his MRI results showed “possible early stages or preexisting stages” of multiple sclerosis (MS) and was referred to a neurologist.

Multiple sclerosis is “a disease that causes breakdown of the protective covering of nerves. Multiple sclerosis can cause numbness, weakness, trouble walking, vision changes and other symptoms,” according to the Mayo Clinic.

Trent Johnston Learned About the Severity of His Astigmatism

Trent was also diagnosed with Keratoconus, which his ophthalmologist, Dr. Hinson, described as an “irregularity on the cornea.”

“Basically, there’s a weakened spot in the cornea and it’s causing … the front surface of his eye to be really irregular shaped,” Dr. Hinson explained during episode 5 of season 15.

The ophthalmologist compared Trent’s eyes to balloons, capable of filling their environment when pressure is applied. “If you take a balloon and kind of push on it, how it’ll pooch out in an area, that’s basically what you’ve got there,” he said. “Just kind of pushing out, causing your vision to be very distorted, and it causes it to where glasses really aren’t the best option for you — as far as getting you seeing the best that we can.”

Trent discovered that his eye issues might be contributing to other problems he’s experiencing, such as vertigo and some of his other “eye movement issues.”

“[This is] the very first time I’ve had a doctor tell me about my astigmatism, and how bad it is,” the father of five said in a confessional. “But either way, it’s not good for me. It’s not good for my eyes, it’s not good for my vision. And it needs to be corrected.”

Astigmatism is an imperfection in the curvature of the eye and causes blurred or distorted vision, per the Mayo Clinic.

Dr. Hinson explained that a switch from glasses to hard contact lenses would be the better option to get him “seeing the clearest.”

That wasn’t good news for Trent as he was uncomfortable with his eyes being touched. “The hard contact lens, when I first hear that, I’m like, ‘Ugh.’ I don’t like anybody touching my eyes or doing anything,” he told the cameras. “But at this point, I’m ready to tackle it and ready to get it fixed.”