My grandpa recently had a surgery for cateracts in which they removed the lens of his eye and replaced it with a plastic replica. He doesn't even notice the difference, save that he can see better. The idea is thus: form the new replacement lens to the perscription of a contact lens, customized to the wearer, thus making permanent contact lenses. This would be wiser for use by individuals at least older than 18, die to changing perscriptions at younger ages (I have had at least 3 different pescriptions at different times). This would also be an interesting implication of Transition lens material; could it be used to make internal sunglasses?-- roleohibachi, Nov 23 2005 Cataract Replacement Lens Info http://www.locatead...icles.cfm/1500/1263Also explains permanent contacts for non-cataract patients [sleeka, Nov 23 2005] Alcon http://www.alconlab...ataract/index.jhtmlExcellent products, machine cut of specialty plastic sheets rather than injection molded. [reensure, Nov 23 2005] They ARE already customized, else they wouldnt work right. Each and every person's eye is differently shaped, and needs a subtly different shaped lens.
But the transition lens material idea, now that is good.-- DesertFox, Nov 23 2005 I agree with you, the transition lens idea is good. Does anyone really benefit from a darker visual field, though, is a question long debated. My opinions range from (+) obviously, plastic protects your eyes be it dark or clear, to (-) you can't take them off, so you'd better like the low light levels, Gramps.-- reensure, Nov 23 2005 Allow me clarify; the replacement lenses were not available with a perscription, which meant he still had to wear glasses to read, and the like. The new lenses only eliminated the cateracts, however [fox] is right, they were customized to his eye shape.-- roleohibachi, Nov 23 2005 I thought they already did this. The <link> claims that the replacement lenses used after cataract surgery now can fix nearly any vision problem.-- sleeka, Nov 23 2005 Well, welcome. Methinks you will do well here, as your ideas are rather well thought out, and interesting.-- DesertFox, Nov 24 2005 My grandpa had a similar opperation, and I think that he must take anti-rejection medication now. You would have to make sure the lenses were not attacked my the body's immune sysem.-- discontinuuity, Nov 24 2005 thanks, [fox], and hello to all you halfbakers, quarterbakers (not specifically [quarterbaker]), eighthbakers... all of (power of 2)bakers!-- roleohibachi, Nov 24 2005 //hello to all you halfbakers, quarterbakers (not specifically [quarterbaker]), eighthbakers... all of (power of 2)bakers!// once again the sixthbakers lose out.-- sleeka, Nov 24 2005 no... 1/2 time 1/2 is 1/4, times 1/2 is one eighth.. it's not a power of two! coincidentally, ever multiply powers of two to pass the time? or am I the only one?-- roleohibachi, Nov 24 2005 this is baked by william gibson.
i have worn glasses or contacts for years. last time i went to the optician i asked about laser eye surgery, something i have always been dubious about due to it's irreversible effect. my consultant explained an experimental australian procedure that inserts a plastic lens underneath the cornea. it basically works as a contact lens that you never have to think about, but can be removed or changed later if your eyesight declines or the technology improves. she thought it would be available here (uk), privately at least, within three years.
would it be possible to use this technology to actually improve basic human vision?-- rainbow, Dec 25 2005 [Disclaimer: I'm no expert or even close but this is my understanding. Your mileage may vary.]
By "implant" I assume you mean an internal addition as contacts are already an external implant--of sorts.
Cataract surgery replaces the internal crystalline, or interocular, lens while contacts and laser procedures deal with the cornea by either modifying its surface characteristics (contacts) or its internal structure resulting in a shape change (Lasik and Radial K).
The cornea acts as the fixed portion of the optic arrangement while the crystalline lens, sitting behind the iris in the ciliary sulcus, provides the dynamic portion (focus) of the optical system. The two are not interchangeable as common corneal topography flaws, such as astigmatism, are not correctable by the crystalline lens.
Although the crystalline lens changes shape on demand (muscles in the ciliary sulcus alter the shape of the soft crystalline lens) the compensatory range is limited to focus functions.-- bristolz, Dec 25 2005 random, halfbakery