Monday’s total eclipse in North America was followed – as eclipses around the world often are – with a surge of web searches for what to do about sore eyes.

Prior to the event, during which the Moon obscured the Sun, experts cautioned against directly viewing the Sun without proper eye protection, advising the use of safety glasses instead.

Fortunately, any discomfort experienced now is unlikely to indicate lasting damage to your vision and typically resolves naturally, according to ophthalmologists.

However, a more concerning issue is solar retinopathy, a painless vision impairment that can occur after prolonged exposure to the Sun, even for just a few seconds.

Solar retinopathy results from damage to the retina, the crucial layer of tissue at the back of the eye containing light-sensitive cells that transmit images to the brain. Despite any discomfort, it’s important to note that the retina lacks pain nerves, so soreness doesn’t necessarily signal retinopathy, as noted by the American Academy of Ophthalmology.

Symptoms of solar retinopathy may include blurry vision or blind spots.

Explaining why this occurs, Professor Bainbridge, chair of retinal studies at University College London, points out that the human eye has limits in tolerating the intensity of light. Directly viewing the Sun, even when partially obscured by the Moon, can exceed this threshold.

Professor Bainbridge advises seeking medical attention if experiencing any issues, although he reassures that lasting damage is not certain.

Although relatively uncommon, there were around 100 reported cases across the US and Canada following the 2017 eclipse, according to a report by the American Astronomical Society (AAS).

Professor Bainbridge, who is also an ophthalmologist at London’s Moorfields Eye Hospital, recalls treating several patients with such symptoms after the UK’s total eclipse in 1999. While most experienced gradual improvement, some sustained lasting harm. As there’s no treatment available, prevention is key.

However, the recent total eclipse presented hidden risks, according to eye care professionals. Dr. Jason P. Brinton, an ophthalmologist, noted that the blocked Sun could mask the natural discomfort and aversion to brightness, potentially leading to increased risk. Additionally, many North Americans witnessed a partial eclipse, which, while less spectacular, could still pose risks to the eyes.

Another concern is keratopathy, a “burning” effect on the cornea, typically caused by prolonged exposure to bright light, such as experienced by welders or those with snow blindness. However, this condition doesn’t usually arise from brief glimpses during an eclipse and often heals naturally.

If experiencing symptoms like headaches after the eclipse, it could be a secondary effect resulting from eye strain, which usually resolves over time.