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What happens to vision when a patient loses one eye? Can he continue to work in the profession, continue his passion, drive a car? Is the case of a Polish athlete who, after losing an eye, remains irreplaceable on the pitch an exception or a rule?
On the last day of August this year, something happened that the German press hailed as a miracle. The Polish handball player playing in the German league scored 11 goals and was chosen the best player on the field. It would not be surprising, if not for the fact that the player can only see with one eye. Just a few weeks earlier, Karol Bielecki received a random blow to the face during a match. Despite the doctors’ efforts, he lost an eye. He announced the end of his sports career, arguing that the specialist operating him had advised against returning to sports. Fortunately, he changed his mind.
When Bielecki decided that his team would win at the end of August, the doctors who commented on his achievements expressed their astonishment. The history of a popular Polish athlete has raised many questions about the principles of human eyesight. Sports commentators, coaches and fans are amazed, and ophthalmologists look at textbooks looking for an explanation of this phenomenon. Is Karol Bielecki, who, despite losing an eye, remained as fit and above-average competitor a medical miracle?
Why are we not cyclops?
In the past, it was believed that we only have the other eye “in stock” – whoever loses one eye will retain the ability to see thanks to the other. More detailed research has shown that this is not true. The other eye allows us to see spatially, it enables us to perceive depth and assess the distance between objects. If our ancestors were born with only one eye, the fate of the human species would have been different. Hunters unable to judge the distance from the game would return home empty-handed.
The images that reach the brain from the two eyes are not identical. The fact that we perceive reality as one coherent image is due to the brain. This is because it puts the two images together and, in addition, makes us perceive them in three dimensions. Without the possibility of superimposing images from two eyes on each other, we would see the world just like the pictures in a book.
If Karol Bielecki read the professional English-language literature on changes in vision after losing one eye right after the surgery, his motivation for rehabilitation and his faith in a quick return to the field would decrease. Doctors talk about the possibility of losing nearly 25% of the field of vision, initial problems with spatial orientation that may result in bumping into objects standing around, problems with noticing objects blending with the background or partially hidden, eye fatigue …
– Monocularity most affects people working in close proximity: hairdressers, bartenders, beauticians, seamstresses, surgeons, drivers and all those who are forced to concentrate their eyesight for a long time – says the specialist in ophthalmology, Dr. Andrzej Mikita, MD. – It leads to a relative decrease in visual acuity in the absence of binocular summation. Another important issue is accommodation disorders, e.g. during reading. Presbyopia will be revealed faster in monoculars and will require stronger correction.
In view of such data, the opinions of the patients themselves look somewhat surprising. Researchers from the University of West Virginia studied a group of 125 people who lost their eyesight. 85 of the respondents stated that it had not changed their lives in any permanent way. Yes, others reported having problems in the workplace or personal problems due to a decline in their self-esteem. However, only about 5% of the respondents complained about various kinds of eye problems.
That great brain
Anyone who is wondering about the phenomenon of the Polish handball player and other people who, despite losing an eye, are coping very well even with tasks that require hawk eyes, can conduct a simple experiment. It is enough to cover one eye and see the world with the other. The sense of depth will remain. Why?
The brain of a person who has had two eyes for at least a few years learns to make proper use of it. He knows that objects far away appear smaller, distance makes the colors less intense, and when moving the head, objects lying closer seem to shift in relation to those lying further. Even with only the signal from one eye to interpret, the brain will create a three-dimensional image. Interestingly, this skill will not go away over time.
– Monocular vision loss requires adaptation – explains Dr. Mikita. – The ability to use only one eye is consolidated in the first year after loss of vision. It seems that Mr. Bielecki, like other patients with this problem, will not only retain the ability to use one eye for the rest of his life, but even improve it over time.
Some of those who commented on Karol Bielecki’s extraordinary efficiency in his first league match played after an injury claimed that the player would play better in places he knew. They argued that the brain of a monocular patient stores so many images of familiar rooms seen from different angles that it was easier for him to create a sense of depth in them. Dr. Mikita disagrees with this, explaining that in any setting, a monocular person will be able to compensate for the loss of some visual field with head tracking movements. To have a field of view that is as wide as a binocular person, he needs to move his head more often. This will allow both to collect more information about the environment (the brain will receive a dozen more “photos” for analysis), and to evaluate movement by changing the position of the image on the retina.
According to most specialists, people who have lost an eye can take the vast majority of their favorite activities over time, without risk. Almost no adjustments are required, for example shooting, playing billiards, photographing, running, painting, swimming and writing. Additional learning will be required, for example, in golf, basketball, football, cycling or skiing, and carving.
When the eyes don’t cooperate
The fact that we all have a dominant eye and a companion eye is known mainly to ophthalmologists, their patients and shooting practitioners (in order to obtain good accuracy and choose the right weapon, the latter must determine which eye is dominant). The fact that sometimes the companion eye ceases to cooperate with the dominant eye, patients can find out only in the ophthalmological office, and this is after months from the beginning of the disease development! It is true that these are rare cases, but each of the ophthalmologists with considerable experience remembers patients who in practice used one eye without being aware of it.
– This problem always affects the non-dominant eye and manifests itself in strange circumstances – says Dr. Mikita. – I remember sick people who reported the lack of vision in one eye when trying to look through the peephole in the door or after accidentally dizzying the eye during the morning washing of the face. Occasionally, follow-up indicated a two-year duration of debilitating disease prior to diagnosis.
Lack of cooperation between the eyes is most often a derivative of cortical aphasia and occurs in people suffering from brain injuries or diseases. A classic example is multiple sclerosis triggering binocular bipartisan. Recognition of such a case in yourself requires self-observation.
– If you wake up and have the feeling of double vision that disappears after two hours, it could be thyroid orbitopathy. When a simple walk impairs visual function, it may be a sign of the onset of a demyelinating disease, lists an ophthalmologist. – If, while working on the computer, we see the faces of our colleagues in the office in a blurry manner, this may indicate a disturbance in accommodation. This affliction more and more often affects overworked people living under permanent stress before 40 years of age. So it is worth checking your eyesight on your own from time to time, for example trying to read the letters from teletext on the TV screen with both eyes. Each of these types of abnormalities requires ophthalmological consultation.
Even when one of the eyes refuses to obey or cooperate with the other, in most cases you can live as before, even engage in professionally demanding team sport, such as Karol Bielecki.
Worth knowing
Third Eye
Since we can see better with two eyes, why didn’t we get the third one to see perfectly? Scientists explain that there was no room for the third eye. First, it is difficult to find the optimal location in the skull for the third eye socket, and second, if the third eye was on a different axis than the others, the brain would have a hard time processing and matching additional information. Two eyes seem just right. However, we all have a kind of “third eye”. It is the pineal gland that produces light-sensitive melatonin. While research is underway to obtain cortical images using artificial eyes, it is hard to imagine that anything that could replace the human eye has ever been created.
In order to have a field of view that is as wide as a binocular person, a monocular person needs to move his head more often. This will allow both to collect more information about the environment and to assess movement by changing the position of the image on the retina.
Text: Sylwia Skorstad, Let’s Live Longer
Consultation: Andrzej Mikita, MD, PhD, specialist in ophthalmology, assistant at the Ophthalmology Clinic of the University Teaching Hospital in Białystok.
Also read: When the eye ages