Olympic gymnast Stephen Nedoroscik became a social media sensation in Paris this summer with his Clark Kent-like glasses, love of Rubik’s cubes, and commanding performance on the pommel horse. He helped the U.S. Men’s gymnastic team secure a bronze medal, its first in 16 years. He also won bronze in the individual competition.

Next up: Nedoroscik will be one of the contestants on the new season of “Dancing with the Stars.” He’s doing all this while living with coloboma and strabismus, two eye disorders. The 25-year-old Massachusetts native, who wears glasses but often takes them off to compete on the pommel horse, has raised awareness about the disorders by sharing his experiences on social media.

Coloboma occurs when the eye does not develop properly before birth, resulting in missing tissue in or around the optic nerve, eyelid, lens, macula, uvea, or retina, according to the American Academy of Ophthalmology (AAO). The condition can occur randomly, be genetically passed down through families, or occur as part of another genetic disorder, the AAO notes.

Symptoms vary based on the part of the eye affected. For example, a damaged optic nerve or macula—the part of the retina that processes what people see in front of them—may result in blurred vision or a visual field defect where parts of vision are missing. Poor vision or loss of vision may cause the eyes to cross or turn outward, says Aileen A. Antonio, MD, FAAN, a neuro-ophthalmologist at Hauenstein Neurosciences, Trinity Health Grand Rapids in Grand Rapids, MI. If the iris is affected, the pupil may look like a keyhole or cat eye, according to the AAO. In Nedoroscik’s case, the condition makes him sensitive to light, according to a report on Today.

While no cure exists, treatments are available and depend on the type of coloboma. Low-vision devices, such as magnifiers, can help people see better, according to the AAO. To optimize the sight they have left and protect their vision, people may wear glasses or protective eyewear. For younger children, eye doctors may patch the better eye or prescribe eyedrops to blur vision in the better eye for a few hours each day. Depending on how the coloboma affects the optic nerve and retina, laser photocoagulation or retina surgery may be recommended to prevent fluid from seeping from the optic nerve into the macula, says Dr. Antonio.

Strabismus, Nedoroscik’s other condition, is the umbrella term for eyes that do not line up with one another, Dr. Antonio says. This can happen vertically, horizontally, or diagonally. “If the coloboma leads to poor vision, the strabismus is usually horizontal, where the weaker eye turns outward,” she says. Symptoms may include double vision, poor depth perception, imbalance, dizziness, or nystagmus, which is a type of abnormal eye movement, Dr. Antonio says.

Treatments include eye muscle exercises, prism eyeglasses, surgery to help align the eyes, and botulinum toxin injections, which paralyze the eye muscles that prevent the eyes from aligning correctly, according to the AAO.

It’s crucial to see a neuro-ophthalmologist for these conditions, which could be related to more complicated neurologic disorders that affect the brain or spine and could impact other organ systems, says Dr. Antonio.