When cataracts develop with age, they can be replaced with synthetic lenses, called intraocular lenses (IOLs). Of course, the original lenses were also literally “intra-ocular” (within the eye), yet they are referred to as the crystalline lens or as the native lens. The first developed type of IOL was the monofocal type, still commonly used. As the name implies, it is designed to focus the best at a given (set) distance, near or far, depending on what a person most needs. Glasses or contact lenses are still needed to correct for the distance not covered by the monofocal IOL.
Premium intraocular lenses are those offering focusing ability at all distances, and there are variations in how this is offered. At the first level of premium, there are the aptly named multifocal IOLs, which are of varying thickness in different areas to handle near, intermediate and distant vision. The amazing, adaptable brain learns to pay attention to the light from the appropriate part of the multifocal IOL. A majority of people with multifocal IOLs are able to achieve clear vision at all ranges without corrective lenses, yet a significant minority still need or want to have these for really optimal vision.
At the next level of premium IOLs are those lenses offering not just multiple focal lengths but the ability to correct other pre-existing vision conditions. The two most common premium IOLs are those correcting for presbyopia - near vision blurriness in those over 40 - and astigmatism, irregular eye shape causing erratic degrees of focus and non-focus. Again the patient should realize that they may not regain 100% normal vision of youth, yet the vast majority experience tremendous improvement in their visual acuity and are very pleased with the change.
The current high end of premium lenses are those that actually “accommodate” to differences in distance much like our native lenses do. Accommodating IOLs are actually attached to the same ciliary muscles that the now-failed crystalline lens was attached to. However they are designed to move forward and back slightly instead of actually changing shape, as when the native lens accommodates. In other words, accommodating IOLs aim for the same goal as the natural lens with a slightly different mechanism.
There are premium IOLs at all levels that have received FDA approval, including the accommodating lenses. However there are still no long-term, controlled trial results for accommodating IOLs. They are no doubt under way but have yet to release final results. However a 2007 study of 59 patients having a total of 95 lenses replaced, found that 50% of the patients were experiencing 20/20 vision at six months after surgery, while 92% had 20/40 vision or better at this same point.
Of the various premium IOLs, accommodating lenses are a bit more involved to put in place, since not just positioning but specific attachments are involved. This suggests a person should seek an eye surgeon who has done many of this type of implant if they are interested in accommodating IOLs. In fact, all of the premium IOLs are more expensive than replacement with monofocal lenses, each to a different extent.
Because the advantages of premium over basic IOLs are not strongly related to quality of life differences – given that vision virtually always greatly improves even if not perfect – most insurance policies do not cover premium IOLs. They will allow for them, but only reimburse the cost of what cataract surgery with monofocal IOLs would cost, the patient making up the difference - and the doctor possibly accepting a bit less. (It never hurts to ask.) The difference in costs is in the two-thousand dollar range, depending on location and individual medical groups. Some predict ‘premium’ IOLs will eventually become ‘standard’ in terms of patient choice and that reimbursement practices will follow. Time will tell.