As observers across the United States prepare to witness a rare solar eclipse this afternoon, ophthalmologists are making sure the importance of vision safety is not overshadowed by the excitement.
As observers across the United States prepare to witness a rare solar eclipse this afternoon, ophthalmologists are making sure the importance of vision safety is not overshadowed by the excitement.
A set of articles published in JAMA outline ways to safely view the eclipse and warn of the vision damage that can occur if viewed improperly. When the moon is only partially blocking the sun, sunlight can reach the macula, which is the center of the light-sensitive retina in the eye, according to a JAMA Patient Page. Just a few seconds of sunlight can damage the retina, and the tissue cannot regenerate, meaning vision loss can be permanent.
To prevent this damage, the authors recommend using special eclipse viewing glasses with aluminized Mylar filters or using shade #14 welder’s glasses. The article also provides instructions on how to create a pinhole projector from paper or cardboard. Ordinary sunglasses will not be sufficient to protect one’s eyes from the rays, nor will devices like binoculars, telescopes, or cell phone cameras.
A Viewpoint in JAMA Ophthalmology explores the mechanisms of sun-related retina damage, known as solar retinopathy. The heat from sunlight, which contains near-infrared radiation, can cause direct burns, which a person might not realize as the light is invisible and the retina does not have pain receptors. More commonly, too much visible light “causes photochemical toxicity through rapid accumulation of reactive oxygen species and free radicals.”
The authors explain that many people erroneously believe that viewing a solar eclipse is safe because the moon is blocking the sun. However, even for the relatively few people in the path of totality, the moon only blocks the sun’s core for around 2 minutes, and will pass through quickly and perhaps unexpectedly. The majority of people who are observing the event from the partial eclipse path will be exposed to part of the sun’s core during the entire eclipse.
It also explains that young adults and children are at higher risk of solar retinopathy, potentially because their eye lens is more transparent, but more likely because they are unaware or misinformed of the eclipse’s risks and precautions. Still, the authors advise readers that through “some simple preparation and instruction, the eclipse can represent the chance to participate in one of the most spectacular natural events our corner of the universe has to offer.”
An example of solar retinopathy in children is presented in a case study also published in JAMA Ophthalmology. It details the case of a 12-year-old girl with juvenile glaucoma who presented to an emergency ophthalmology clinic with blurred vision after she had stared at the sun for 1 minute the day before. Upon examination, clinicians found that her visual acuity had worsened since her last visit and her eyes, specifically the fovea, had experienced hypopigmentation. These symptoms were consistent with solar retinopathy.
With no treatment options except observation, subsequent follow-ups found that “her visual acuity remained stable and no further changes on examination or macular optical coherence tomography were noted.” The case illustrates the importance of preventing solar retinopathy through proper sun safety, considering the permanent nature of the damage and the lack of available therapies.