It was just as good that 15year old Boro had been chosen to lead the discussion at today’s United for Vision Club’s meeting. I wasn’t feeling well – possibly from exhaustion.  Secretly, I wished we could find some excuse to call off the meeting. Unfortunately there was none! Everyone was anxious to know how a change in vision could be an early warning sign of an eye problem.

“Boro,” I called out. “Please take the stand?” He sauntered majestically to the front of the class carrying a large carton containing some stuff. He placed it gently on the table and like a skillful speaker tried to get the attention of everyone by cracking a joke. It fell flat! Undaunted, he asked, “Can everyone in this room close his eyes just for two seconds?” We all did wondering where this little brat was taking us. “You may now open your eyes?” he commanded again. We complied. He smiled and said, “Between the darkness created when you shut eyes and the brightness in the room when you opened your eyes is a wide range of sight.”

There was pin drop silence. He had captured the attention of his audience. My fatigue evaporated. Now I, like others present, was waiting for the next word and the next sentence. Slowly and gently, he unfolded the flaps of the cardboard carton and brought out a calendar; placed it at the distance and asked me to read out loud the quote at the bottom of the page.  It was a struggle to read, from the back of the class where I was seated, “Working together we can eliminate avoidable blindness in our midst.”

Then Boro went for the light switch to which he had connected a device. “This is to control the amount of light in this room,” he explained as he turned the device clockwise. The lights were brighter and now I could read not just the sentence but also the name of the author which was written in smaller prints. Then as he turned the control slowly anticlockwise the wordings of the quote gradually faded away until even those on the front row could not read it again.

Boro paced up and down and announced gleefully, “I have just demonstrated that it is not only the distance from an object that determines its visibility, equally important is the amount of light on the surface of the object. It is this light on the surface of the object that is directed to the eye and makes it possible for us to see. When the light in the room is inadequate, the light on the surface of the object is also reduced proportionately and visibility is poor. Certain changes in the structures of the eye can reduce the brightness of an object and eventually make it impossible to be seen at the same or even nearer distance than we used to see it clearly before.

I admire the young man. He demonstrated a good knowledge of the subject. It was obvious from the delivery that he understood the underlying principles. As if he could read my mind he declared with confidence, “Once you understand this process of light being transmitted to the eye from the surface of objects, then you already know what things can cause a change in what you see.”

He opened the carton once again and brought out the model of an eye. “There are three transparent structures though which light from an object must pass through before registering the information on the retina,” he said, demonstrating the structures as he talked. “These are the cornea, the lens which is inside the eye behind the iris which gives colour to the eye and then the jelly like mass called vitreous humour.”

Like a master lecturer, Boro concluded with a question “Isn’t it therefore obvious that anything that reduces the transparency of these three structure would reduce visibility and be a danger sign of an eye problem? Opacities of the cornea or lens or vitreous would interfere with the light reaching the retina.

Such opacities in the early stages may not be very visible to the naked eyes but may be picked up by special instruments. Most of the avoidable causes of blindness in our country are at the level of the cornea or lens.

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