Solar Eclipse Vision
08172017_eclipse_glasses_iStock AlbertoRoura/iStock.com

A woman views a solar eclipse through special filtered glasses in March 2015 in Barcelona, Spain.

August 17, 2017

Pennsylvania optometrist on solar eclipse: 'It's not worth it'

Vision professionals warn of solar retinopathy

With less than a week to go before the solar eclipse arrives on Aug. 21, one Pennsylvania optometrist has joined a vocal contingent of vision professionals who advise against looking at the rare spectacle, even with protective eyewear.

"It's not worth it," Chambersburg optometrist Joel H. McGahen told HeraldMailMedia.com.

McGahen is one of many in his field warning people about the risk of solar retinopathy, which occurs when the retinal film at the back of the eyeball is burned. Experts say just a few degrees of heat from solar radiation is enough to cause permanent damage to the cells that process light and help you see. 

McGahen said the eclipse could raise the temperature on the back of the eye by up to 22 degrees.

A receptionist for Dr. McGahen was adamant in a phone call Thursday afternoon about the severity of the risk. 

"It only takes 30 to 60 seconds and the damage will be done," the receptionist told PhillyVoice. "Whether you have sunglasses on or not, do not look at the eclipse. It might be cool or something that doesn't happen very often, but it's extremely dangerous. He's advising all of his patients, friends and their families not to look at the eclipse."

The science of the event itself heightens the risk of retinal injury. A viewer's pupils dilate to three times their normal size during the dark period of the eclipse but are then exposed to UVB rays that are stronger than what we usually see directly. The risk is particularly serious for children and adolescents whose eyes are not fully developed.

Researchers at Penn State University warned Thursday that viewing a solar eclipse is similar to getting beamed by a laser pointer.

“There is no safe amount of time to look at the sun during a solar eclipse without proper eye protection,” said Dr. Joseph Sassani, an ophthalmologist at Penn State Health Milton S. Hershey Medical Center.

What is proper eye protection? NASA, warning curious Americans, put together a list of criteria that meet basic standards for eclipse viewing glasses and handheld solar viewers.

Dr. Russell N. Van Gelder, a clinical spokesperson for the American Academy of Ophthalmology, explains in the video below how the solar eclipse can damage the retina and what kind of eyewear is required to ensure safety.

Symptoms of solar retinopathy could include blind spots, loss of visual acuity, changes in color vision or distortion when looking at straight lines or grids. McGahen said eye damage may not be immediately apparent because blinking will push away dead cells that expose nerve endings. 

His professional advice? Watch a recording.