RE: Sleep Apnea & Anesthesia When Having Surgery
I am sorry, I did not mean to confuse you here or get you worried. I was referring to a certain type of corneal surgery which might have been what you were indicating in your first posting. If you doctor hasn't mentioned it, it is because that is not an option. He is fully qualified and will judge the correct procedure for you, and you should trust him in all of this - your description in the posting is too general for me to make any real judgement and I did not intend to mislead you or worry you in any way. But I will elaborate on it to help you understand:
It is not exactly removing the cornea, it is scraping away the top layers of it. The PRK procedure involves use of an "excimer laser" to remove anywhere from 5 to 20 percent of the cornea -- no more that the thickness of three human hairs. A "polisher" is used to do that, and then the laser corrective treatment is performed. All of this is painless. The polisher part takes about five seconds. The laser procedure takes anywhere from 10 to 40 seconds. Then a soft contact lens is put on your eye, and you are done. The total time for the procedure is about one minute per eye. Healing is about a week. This may not be an option in your case, and certainly not if we are talking about a procedure involving the lens or the deep tissue of the cornea. However, Corneas can heal quite nicely under certain circumstances and do grow back given a scratch or the above described procedure. I might mention that PKR is a slightly older procedure than LASIK, but fell out of favour in the US mostly due to the cheaper and easier to use equipment of the LASIK system (and LASIK's excessively aggressive marketing). PKR is making a come-back, and I think for the better, since long term eye health seems better under PKR than under LASIK. The US armed forces offer both procedures for free to active soldiers, sailors and marines, but each branch has strong rules as to what type for what activity and they are very insistent on these rules - naval aviators are not allowed either type of surgery, air force pilots only PKR, and ground soldiers are allowed both (a lesson they have learned in Desert Storm about how useless contact lenses and glasses are in the sand combat). Since the armed forces actively track results of such procedures for the entire life to the patient (at least if they use the VET Hospital system after passing out), we should have effective long term data on both these procedures, but alas, long after you and I are beyond caring, I should think, since both of these procedures are relatively recent inventions, medically speaking.
Keratoplasty (corneal transplant) is done for a variety of reasons, all due to damage of the entire layer or most of the layer of the cornea: A cornea that bulges outward (keratoconus). Thinning of the cornea. Cornea scarring, caused by infection or injury. Clouding of the cornea. Swelling of the cornea. Corneal ulcers, including those caused by infection. Complications caused by previous eye surgery. In each of these cases, a corneal ablation is not a possible cure, so a transplant is needed. The operation is quick, done as an outpatient procedure, and is usually painless, with a very high success rate.
So, depending on your problem, a corneal ablation might or might not be recommended. Your doctor knows what is right for you in this case, so trust him. If that clinic commonly offers PRK for eyesight correction, then they have the necessary machines at hand. However the surgery you describe may be for a deeper problem of the cornea than an ablation could correct. And of course, in cataract surgery, the cornea is not the target at all; commonly, an incision is made to the side of the cornea - the lens is then ablated with a probe, and removed. A plastic lens, known as an Intraocular Lens (IOL) is then inserted, the incision stitched, a covering bandage of some sort affixed (varies depending on procedure and country rules) until the incision heals (around thee days to a week) and anti-biotic and dilation drops are given to you to apply to the eye during the healing procedure. There are various techniques, but the variance is minor and depends on the needed procedure and the established guidelines for that country (we do it differently here than in the UK, for instance, but the variance is minor - we put a covering lens on keep the incision clean, the UK doesn't). Your vision should correct itself over a week or so, and take around a month to stabilise, after which you may or may not need glasses, and a new prescription.
A variety of IOLs with different features are available. Some IOLs are rigid plastic and implanted through an incision that requires several stitches (sutures) to close. However, many IOLs are flexible, allowing a smaller incision that requires no stitches. The surgeon folds this type of lens and inserts it into the empty capsule where the natural lens used to be. Once inside the eye, the folded IOL unfolds, filling the empty capsule.
Some types of IOLs block ultraviolet light and other types of IOLs work like bifocals to provide multifocal vision — both near and distant vision. Your doctor will determine what is right for you.
Typically, during eye surgery, the sedative you will be given will leave you awake, but groggy, so apnoea is not an issue in such cases. Only certain types of eye surgery require full narcosis, and I do not know if that is going to be your case, but if it is, talk to the gas -passer about it first. If you are having an out-patient procedure (meaning you don't stay overnight), the likelihood is that you won't be given a full narcosis, since that is usually for more complex or severe eye operations that require you to remain in the hospital.
Typically, if both eyes need to be done, the surgery is scheduled a month or so apart.
Legally Blind is not the same as being blind. It means you have vision, but your vision is not sufficient to drive or operate machinery. It does not mean you cannot navigate or live a relatively normal life. Of course there are gradations in this, but it does not necessarily mean you will not see at all, and given time, you can adjust. I know a lady, now 76, who has had dry macular degeneration since she was a teenager - she sees only a sliver of world in a sort of circle, with the centre of the image blocked out. Yet she walks through the busy centre of Zurich with assurance and ease, reads (although she has to hold book up close and use a special pair of glasses), and even watches TV and is a regular opera goer (second row, four seats down from me). Legally she considered cane-blind (meaning she is supposed to use a cane to navigate, although she does not - but she does have a walking stick, and it confers certain advantages - all public transport is free, and any event she goes to she is given two tickets, one for her and a free one for a companion to act as "interpreter" and guide, which she doesn't need, but uses to her advantage). She lives a full and I think rather joyous life, we talk often and I am in full admiration at how well she gets on, but in all truth, what is happening is that the brain has adjusted to the point that it maps out her vision ins a way that allows her to make sense of the world. Given time that is what will happen to you as well - our vision is only what our brain makes of it - we have grown used to seeing a certain way, but when that is changed, our brain takes a wile, then adjusts its "interpretation" method to produce an image that makes sense to you. She doesn't see the world as I described, exactly, as a ring with a dark centre - her brain adjusts it to giver here a picture that makes sense to her.
So don't count yourself out just yet. Let your doctors guide you, they are very experienced in this and know what is best to do, and above all, don't panic. You are in good hands and they are trying to make sure you get the best care they can give you. I know it all looks grim at the moment, but the results are not in, just yet, and there is a lot of "magic" still to be performed before you are stuck with no more options, so try to relax and let your very qualified professionals help you.