This newer generation of lenses have replaced the old-fashioned "hard lenses" with plastic that allows oxygen to pass through, thus the term "gas permeable". This permeability has alleviated most of the complications associated with hard lenses. This is important from an eye health standpoint because the cornea is the only external tissue of the body that must get its oxygen supply from the atmosphere. Because of their rigidity, these lenses supply superb vision for those with even large amounts of astigmatism. These lenses are smaller than the disposables and can last up to several years, so the long-term cost is less. The initial comfort is less than disposables but most patients feel the same comfort after about of week of wear. In addition, RGPs are prescribed for that patients who can not obtain clear vision with glasses or soft lenses due to keratoconus or corneal transplants. Bifocal RGPs are also able to provide excellent distance and near vision. Approximately 5% of patients cannot adapt to these lenses due to comfort issues. We conduct tests during your exam that can be a good predictor of your success.
These lenses take advantage of technologies between the comfort of soft disposables and the excellent vision provided by a rigid gas permeable (RGP). These lenses have a rigid gas-permeable center molded into a soft lens skirt or perimeter. They are a fantastic solution for those unable to adapt to the feeling of RGPs but who find that the vision of the soft lenses is unsatisfactory. They are cared for similarly to that soft lenses and they are roughly the same size. Their lifespan is between 6-12 mo. Their development has kept many patients in contact lenses and has prevented many with diseased corneas from going the route of a corneal transplant.
Due to the recent advancement in manufacturing capabilities, scleral lenses are the latest in contact lens technology. They are larger and made from a highly oxygen-permeable material. In the past, labs could not make a rigid lens this size, without imperfections. Because of their large size, these lenses have the same initial comfort as soft disposables. The smaller gas-permeable RGPs fit on the cornea, between the eyelids, and thus the patient feels the edges upon blinking. These lenses, like RGP's, are prescribed for those who can't obtain good vision with glasses or soft contacts because of corneal distortion from keratoconus or a corneal transplant. Because these lenses are designed to vault over the cornea, they are prescribed for very diseased corneas that can't even be fitted with an RGP. All corneal irregularities are filled in with one's own tears, and the smooth front surface of the lens bends light like a "new, healthy cornea". Scleral lenses are also excellent for those with very dry eyes, as the lenses are inserted with a copious amount of saline, which remains behind the lens and keeps the eye moist throughout the day.
These are fit much differently than all previous lens designs, therefore requiring more time at fitting as complete settling of the lenses takes about 20-30 min. At the end of your contact lens consultation and fitting, we will be able to ascertain if you would be successful in this technology. This saves the patient unnecessary time spent and cost.
With all contact lenses, the fitting properties of a lens are determined by several factors including lens curvature, diameter, and power. Our goal is to provide you with contacts that fit well enough to center properly but not so tight as to prevent an adequate oxygen supply to the cornea. At Skowron Eye Care, corneal topography takes measurements at over 1000 points to give a 3D map of your eye to enable us to design the most precise, accurate fit. Cornea, eyelid health, and tear quality are evaluated to ensure safe contact lens wear.
There are many different brands or designs of disposable soft contact lenses. Each manufacturer claims to be better than the next and does its best to ensure that the doctor uses their lens. Considerable professional judgment is required for proper contact lens fitting and follow-up eye care. Many times, a contact lens must be worn for several weeks to determine if it is a healthy fit for the eye. We have NO allegiance to ANY manufacturer, and our choice of lens design is made by our professional judgment and testing results that would provide a safe, comfortable fit. Be aware that others look to financial incentives offered by the manufacturers as a reason to recommend a lens.
In addition to the initial fitting, we will give you thorough instructions on lens insertion and removal, lens care, and handling. This is something patients are frequently concerned about and is easily mastered with a little practice. The cleaning procedures are simple and will be explained and demonstrated during an instruction session with one of our staff members. Not all solutions are the same, as patients can be allergic to one and not the other. If you need additional help, we will schedule more instruction sessions at no additional charge until you feel comfortable and competent.
Like any medical device, contact lenses must be monitored on a regular basis. Topography is taken frequently to ensure that the corneas are healthy, and are free from distortion and warpage and that the lenses fit properly. The number of follow-up visits may vary due to the complexity of the case.
If you have any other questions please call us at (630) 984-6850 today!