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Adjustable-Focus Glasses Can Replace Bifocals
Hugh Pickens writes "The NY Times reports that inventor Stephen Kurtin has developed glasses with a mechanically adjustable focus that he believes can free nearly two billion people around the world from bifocals, trifocals and progressive lenses. Kurtin has spent almost 20 years on his quest to create a better pair of spectacles for people who suffer from presbyopia — the condition that affects almost everyone over the age of 40 as they progressively lose the ability to focus on close objects. The glasses have a tiny adjustable slider on the bridge of the frame that makes it possible to focus alternately on the page of a book, a computer screen, or a mountain range in the distance. 'For more than 140 years, adjustable focus has been recognized as the Holy Grail for presbyopes,' says Kurtin. 'It's a blazingly difficult problem.' Each 'lens' is actually a set of two lenses, one flexible and one firm. The flexible lens (near the eye) has a transparent, distensible membrane attached to a clear rigid surface. The pocket between them holds a small quantity of crystal-clear fluid. As you move the slider on the bridge, it pushes the fluid and alters the shape of the flexible lens."
Don't use cleaning fluid, tissues, or even those special cloths. Use soap and water only. Run water over your lenses to get the larger dust particles off, then wet your fingers and apply a couple of drops of dish detergent to them. Use this to get any remaining dust and oily residue off the lenses by rubbing the lenses with your fingers. Rinse the lenses under running water. Repeat as required. You can shake most of the water droplets off, and if you want to get rid of all of them, dab the lenses with a soft cotton towel. You lenses should remain scratch free for years.
You're only semi-conscious; they drug you into what they call "twilight sleep". They use anesthetic eyedrops to numb the eye and they put an IV in your arm with the "twilight sleep" anesthesia. They tie your arms to the gurney "so you won't try to help the doctor". The only unpleasant part is when the needle actually goes into your eye, but it's not painful, only shocking and wierd. They have some sort of frame over your face that lets them see inside your eye with a microscope (they dose your eye with dialation drops as well as anesthetic) and holds your eyelid open.
You don't see the needle coming towards your eye. I journaled about it; the link is in the comment you responded to. The needle goes through the white of the eye and they shoot ultrasound through it to turn the lens to mush, suck the mush out and insert the prosthetic lens. It sounds bad, but it isn't. The best part is I wore thick glasses all my life, I was severly myopic. The CrytaLens cures myopia (nearsightedness), presbyopia (farsightedness), astigmatism, and cataracts. The eye I have the implant in is now better than 20/20 at all distances, but the surgeon said mine worked out better than most.
Now, a vitrectomy, that's a nightmare. I wouldn't wish one on anybody, but it sure beats the certainty of absolute blindness. BTW, one slashotter asked me to warn people before I link the vitrectomy journal, it really freaked him out. There's a link to the wikipedia article about victrectomy in that journal, and there's a picture in the wikipedia article that is NOT for the faint of heart. Pray you never have a detached retina!
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