It's like seeing the world through a keyhole

Marco Casadei, Alumnus, chess player and sportsman, is the first visually impaired student to graduate with a degree in Aerospace Engineering in Italy. He told us how he lives with 20/2000 vision.

When he was finishing the liceo scientifico in Cesena, Marco Casadei used to play football and chess. When the time to came to choose a university, he decided to study Aerospace Engineering at the Politecnico di Milano. He graduated last September and today he is taking his first steps in the world of work. “One field that has always interested me is reliability & safety, risk assessment. I am also interested in operations, so project management or production planning, supply chains.”

Another of his plans for the future involves the possibility of creating an association for visually impaired engineers and tech graduates in Italy. Indeed, Marco is visually impaired: he suffers from bilateral congenital glaucoma, a condition that affects the optic nerve. Over the years, he has undergone around thirty operations stem the progress of the disease, including during his university studies.

I had to suspend my studies for a few months two or three times to undergo the necessary surgeries. Around the start of my second year, my vision deteriorated: it went from around 20/400, the worst extreme of normal vision, i.e. severely partially sighted, to my current vision which is difficult to measure accurately. I had to learn how to study again, essentially from scratch"

he told us.

Glaucoma is one of the leading causes of blindness in Italy. It typically develops in old age; but with congenital glaucoma, if it is caught in time and kept under control, you can even reach sixty with some residual eyesight. This is the case for Marco. But what does “residual eyesight” mean?

20/2000 VISION

We often hear about dioptres, but, in the case of visually impaired people, the problem relates to visual acuity (also known as “visus”). The theoretical perfect sight is measured as 20/20 visual acuity. A person is defined as partially sighted if their visual acuity is measured as 20/200 or poorer: “A dioptre is a unit of measurement relating to the focal point of the eye,” explained Marco, “which only requires a lens to be corrected. Instead, visual impairment is the loss of visual acuity, that is a loss of sight. It is defined as the ability to see two distinct points that are near one another but not overlapping, which is measured in twentieths, with perfect sight being 20/20. Naturally, Marco’s case requires more than just a pair of glasses. The two things can coexist: for example, today today I have residual vision measuring between 20/1000 and 20/2000 of visus. In addition, I have a deficiency of -7.5 dioptres (I think!), which is why I go around wearing milk-bottle glasses!”

marco casadei
Courtesy of Marco Casadei

Visual acuity varies greatly depending on the background, the light conditions, the contrast between objects and many other variables that affect it. “In practice, I cannot recognise faces, I only see outlines when they are very close to me. I cannot see road signs or traffic lights (actually I can see traffic lights at night because of the background and contrast). It is difficult to give a real idea of what it means, especially because, in familiar surroundings, the brain completes the images with the missing elements: if you saw me on the route that I take every day, if it were not for the white stick that I carry with me, you might not notice that I'm visually impaired. However, if a new pole hwere to be installed on the pavement, I would almost certainly walk straight into it! One time, as I was rushing to get on a train, I half fell into a manhole near the yellow line on the platform: the workers who were working on it had thoughtfully moved out of the way for people getting on the train, without putting up any protection, thinking 'come one, it’s only 30 seconds, it's not like a blind person is never going to come past right now…’.”

In addition to the reduced visual acuity, glaucoma also causes a drastic reduction in the field of vision“Mine has a range of about 3-4% of a normal field of vision. Basically, it is more or less like seeing the world through a keyhole. But fortunately, unlike being locked behind a door, all of my other senses work normally, and human beings have a great capacity for adaptation, especially during childhood. There are thousands of viable, simple and even trivial little tricks, alternative strategies and solutions for overcoming the limitations imposed by our little keyhole. Other difficulties arise from the fact that my field of vision is not homogeneous; it behaves like a dirty window. Sometimes you think you have a picture of your surroundings and suddenly you notice things that surprise you”. 


Studying is not always easily, especially in the case of technical and scientific subjects. Marco is the first visually impaired graduate in Aerospace Engineering in Italy. “When the time came to choose a university, I had to fight because I was told that, for me, engineering was absolutely out of the question. When I insisted, they said: "OK, so how about computer engineering?" because it was the only course thought possible for a blind person.

But I said no, I wanted to study what I really liked. Il Politecnico mi ha aiutato molto. A lezione mi avvalevo di uno strumento detto video-ingranditore: è come una telecamera che riprende la lavagna e la restituisce ingrandita sul portatile.

At home, I have a desktop magnifier for text and exercise books. My course mates and the logistical support provided by the Politecnico di Milano helped me to complete the course. . Certain things were harder than others. At the Politecnico, there are exams which require you to have an overall view. For example, the structural mechanics exam: not having an overall view of the plans and diagrams at a glance forces me to look at every single part of the page and memorise it. The fact that I have played chess since I was small helped me with this.” In 2014, Marco founded the student association Scacchi Polimi, which has since organised tournaments, courses, conferences and participates in team competitions.


Other than Marco’s studies, there are many ways in which his visual impairment has affected his university life. “The Politecnico di Milano is very inclusive, I have had all the support I could have hoped for. For example, I was offered a chaperone service: a student would come to meet me at the train station in Bovisa and accompany me to the lecture halls. It was useful during the first semester; then, once I had learnt the routes, I could do it on my own,” he told us.

“One of these students, Filippo, is still one of my best friends in Milan. During those first months, he also really helped me to settle in to the city, introducing to me to his friends inside and outside of the university, which helped me in particular to overcome certain social difficulties. A totally new and large group, such as a university cohort with 150-200 people, is a complex situation for everybody, but imagine what it is like for someone who is blind: one day you talk to the person next to you, just to start getting to know the people on your course. But the next day, unless he comes to find you, you certainly won't find him again very easily. Then there are certain objective limitations: one trivial thing is that I couldn't stay on in the library to study because I need a certain environment and specific tools. I am also a lot slower than the others, which makes studying in a group difficult.”

Having to deal with a disability always has direct effects (reduced autonomy for example) but Marco explained that others are indirect, referring to the social sphere. “It is harder to talk about, we don't have the language. For someone who is visually impaired for example, it can be difficult to establish relationships or understand the dynamics of a group because body language is fundamental and we can't see it. A blind person may also find it difficult to create their own body language because they don't have a reference model to imitate. The result is that, in the eyes of a sighted person, you might seem in another world…and you risk hearing the classic line ‘poor thing, leave him alone’. To be clear: these problems are not inevitable nor are they the norm. However, we must be aware that they can exist. Besides, just like anybody else, we are first and foremost people, so we too have a huge range of different attitudes.

In my view there is only one solution: culture and inclusion. On all levels and in all areas.

However, that means us too, and our own willingness to be included. In fact, another big problem is the tendency of some visually impaired people to marginalise themselves. It is something that I fight against a lot, for example in the context of chess. But, apart from that, Italy is one of the best countries in the world to live in as a visually impaired person. The important thing is not to become complacent.”


Alongside his studies, Marco plays sports: He is an expert chess player and, for a few years, he played first football and more recently in a blind baseball (BXC) team, Lampi Milano (where he is blindfolded so he cannot cheat). When he told us this, we at the editorial team did not immediately understand how the blind could play a sport like baseball.

Inclusion, also taken to mean the normalisation of disability, also comes from abandoning the rhetoric of the super-hero who, with extraordinary powers and motivation, is able to achieve incredible things despite having a disability (or perhaps thanks to it)

explained Marco very patiently. “Generally, the visually impaired have completely normal hearing and auditory-spatial awareness. They are just more accustomed and trained to interpret specific sound feedback (the classic example is the absurdly quick text-to-speech that only we understand, because we use it all the time).”

Baseball for the visually impaired works like this: the ball is hollow and has bells inside, so it can be located by the sound it produces. 

When you are batting, there is no pitcher. A visually impaired batter would not be able to hit the ball on the fly. He holds the ball with one hand and bats it with the other. He then starts running by following the sound feedback from the first base: a klaxon. The second and third bases are marked by a sighted assistant who uses clappers. As you get closer, the frequency of the clappers increases and “at that point the best players (not me!) dive towards the base.” Between third base and home base there is no feedback. “The assistant points you towards home base. You need to be able to run straight. It is a matter of practice and, once you have acquired the right sensitivity, you can rely on the feedback from your feet, feeling the difference between the parts of the field with a dirt surface and those that are grass.”

When fielding, the important thing is to reach the ball before it stops: “if it stops making a noise, you’ll never find it! Otherwise, you need to have a clear idea of the layout of the field and remember where the ball was before it stopped moving. There are five fielders who work together vocally as they search the field. The receiver is the only sighted player in the team. Once a fielder finds the ball, the receiver indicates his position vocally and it is up to the fielder to throw the ball back as accurately as possible. The plays are very quick and if you mess up the throw, the receiver loses lots of time by having to recover the ball from perhaps 20 or 30 metres away. Many matches are decided by the accuracy of the throws.”

“Finding a sound ball in your area of the field is a difficult and complex technical skill. However, if you practise, it can go from almost impossible to more or less possible depending on your talent, which becomes exceptional only for the Cristiano Ronaldos and Rafa Nadals of blind baseball. Of course, when you watch a blind baseball match for the first time, it looks incredible and you often hear things like ‘OK, but when do the blind people start playing?!’ But if you watched all of the matches in the competition, you would be amazed by the wide range of abilities and would marvel at the genius BXC player, the ace who manages to defend the whole field on his own or, when batting, regularly hits home runs (when the ball travels over 80 metres from the plate in just a few seconds) while you would also understand that more or less anybody could play at basic level.

To give you another example, it's the same as for a non-chess player, who is usually amazed to see that I can play a whole game in my head without a chessboard; it seems absurd, doesn't it? But if you know the “tricks of the trade”, you know that it is nothing special; it is a very useful skill that all chess players have, but some have developed it further than others. Then there is the master who can play 50 matches at the same time in his head…He definitely does have a superpower!”

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Credits home/header: courtesy of Marco Casadei