A spot that stays in the same place, straight lines that seem to undulate… After a direct observation of the Sun, certain signs must be taken seriously. Here’s how to spot them and especially when to consult them.
The trap: having sore eyes is not the right indicator
The day after an eclipse, a question may come back insistently: “Have I damaged my eyes?” And the absence of pain can give a feeling of relief. However, this is not necessarily reassuring.
Direct observation of the Sun can cause
solar retinopathya lesion of the macula, the small area located in the center of the retina and essential for precise vision. This damage can be particularly misleading: unlike irritation of the surface of the eye, it may not cause any pain at the time of exposure. In France, the precedent of the 1999 eclipse led to the confirmation of 253 eye lesions, including 147 retinal damage and 17 serious cases.
“The spot or halo that you often see may be an afterimage, like a photo flash… What should alert you is the opposite: a fixed spot, in the center, that doesn’t go away, or straight lines that become wavy.”explains Dr. Ygal Boujnah in the video published on his Instagram account.
In other words, it is not necessarily what we feel that counts, but what we really see.
A grid grid can reveal an anomaly that has gone unnoticed
This is precisely where a surprisingly simple tool comes in: the Amsler grid. This grid is commonly used in ophthalmology to look for abnormalities in central vision, particularly in the macula. Its principle is very simple: by looking at the point located in the center, you must observe whether the lines remain straight and regular.
“So here is the tool that we, ophthalmologists, use to check central vision: the Amsler grid.”explains Dr. Ygal Boujnah.
The test is carried out eye by eye, alternately masking one then the other, so as not to let one eye compensate for a possible anomaly in the other. A distortion of lines, a blurred area or a dark spot that remains in the same place should attract attention.
A simple check can thus highlight something that one would not have spontaneously noticed.
But we must keep in mind an essential limit: a home test cannot confirm retinal damage. It can only constitute a warning signal.
Black spot, gray area, wavy lines: signs that should not be trivialized
After unprotected observation of the Sun, certain transient visual phenomena can be impressive without necessarily corresponding to a lasting lesion. An afterimage, comparable to that left by a photographic flash, can in particular gradually disappear.
What deserves more attention is an anomaly which
persists and stays in the same place in the visual field.
Dr Boujnah mentions in particular a fixed central spot, a grayish area or a loss of sharpness. These manifestations may not be immediately noticeable: they may appear within a few hours, or even the next day or two days later. Another particularly evocative signal is the distortion of straight lines: a door frame, a window or the lines of a grille can suddenly appear to undulate.
In this context, it is better not to wait until the worry sets in or the symptom disappears on its own to seek advice. A persistent anomaly after direct observation of the Sun warrants rapid ophthalmological advice.
What if the retina has really been affected?
Treatment depends on the nature and extent of the lesion. The ophthalmologist can notably examine the retina and perform OCT imaging, which allows the different layers of the retina to be precisely observed. However, there is no treatment that can instantly “repair” damaged photoreceptors.
This reality deserves to be heard without dramatization. Brief exposure, followed immediately by the reflex to look away, rarely causes lasting damage according to Dr. Boujnah. The risk is mainly linked to the prolonged exposure to the Sun without appropriate protection. The main thing is therefore not to panic, while remaining attentive to your vision in the hours and days that follow.
After an eclipse, taking a few moments to check each eye separately can be reassuring. And if a central spot persists, if the straight lines become distorted or if the sharpness drops, the right reflex is not to search for a long time on the Internet: is to consult an ophthalmologist. Vision is precious, and when an anomaly appears after a direct observation of the Sun, it is better to have a reassuring examination than to have doubt set in.