Orthokeratology / Contact Lenses That Correct Vision
We Fit Paragon CRT Lens
Dr Consor and Dr Nguyen are certified to fit the Paragon CRT lens
Refractive therapy also known as Orthokeratology (Ortho-K) is a non-surgical process that reshapes the cornea (the window of the eye) using a custom designed reverse geometry gas permeable (not soft) contact lens. A reverse geometry design differs from the traditional contact lens design in that the lens is flatter in the center and becomes more curved in the periphery. Customized aspheric curves that match your cornea are applied put on the back of the contact lens. The center of the lens gently applies pressure to the central cornea making it flatter.
The process is painless and by accurately controlling the corneal flattening it's possible to bring the eye in to correct focus and compensate for myopia (nearsightedness) and small amounts of astigmatism. At this point in time orthokeratology will not correct for hyperopia (farsightedness). After removal of the contact lens the cornea retains its flattened shape for most of or all the remainder of the day.
The lens is placed on the eye approximately 30 minutes before bed time and then removed in the morning. In some cases a Day Wear program is prescribed. The patient will wear lenses for part of the day and remove the lens with resulting clear vision for the remainder of the day. As each case is unique depending on the shape of the cornea, the elasticity of the cornea and the patient’s lifestyle needs. In some cases patients wear a retainer lens for one to two days and then go a few days without any correction. Once their vision subjectively changes they put lenses on to re-flatten the cornea.
In most cases results from Ortho-K are experienced after the first day or night of lens wear. Vision in the majority of cases immediately improves. Vision improvement should be noticed each day until the eye stabilizes. Some cases can take from three to six months until vision is functional and stable. Although our goal is free the patient of the need for glasses in some cases glasses may be needed for reading or part time wear. RT / Ortho-K does not work for every one. We will be happy to let you know if you are a candidate.
During the fitting process you will need to return to the office for a series of visits so that we can monitor the results. In many cases it may take more than one pair of lenses to finalize the fit. The case fee you pay will include the contact lens examination, all lens designs and additional pairs of lenses to finalize the fit. Also included are all your follow up visits for six months. Typically the lenses need to be redesigned and changed every 12-18 months to accommodate the flatter cornea and enhance the results. Fresh lenses will also provide the eye with the oxygen that it needs to maintain good ocular health. The shape of the cornea can be easily fine tuned by minor modifications in the lens design. Improvement in vision is temporary; therefore lens wear must be continued on a prescribed wearing schedule to maintain the therapeutic effect. Once you stop wearing these lenses chances are your vision will go back to wherever it would have been if you never wore the OrthoK lens. There is some long tern therapeutic benefit (permanent improvement in vision without lenses) but the results can’t be guaranteed as each person’s corneal anatomy and physiology differs.
Ortho-K for all ages
The principle of flattening the cornea is the same for adults and children. There is a greater potential therapeutic benefit for children in that the earlier a person is fit with the Ortho-K lens the greater the chance of slowing or stopping the progression of their myopia. This may result in no need for glasses or a lesser prescription (thinner lenses) that otherwise might be required by the time they reach the teenage years.
Federal Drug Administration (FDA) approved
The FDA has approved rigid gas permeable contact lenses for overnight Ortho-K wear. Prior to approval the FDA monitored clinical studies for 15 years to evaluate the risk and benefits of the overnight procedure. The procedure is FDA Approved. Daily wear traditional contact lenses are worn all day and extended wear lenses are worn 24 hours a day for consecutive days. Ortho-K overnight lenses are only worn 6-8 hours a night or as a daily wear lens in some cases. For more information on the subject please visit: www.ortho-k.net and www.paragoncrt.com.
Non-Laser Vision Correction / Intraocular Lenses
The Visian Lens and The Verisyse Lens
Using a lens implant to correct for vision problems is a non-laser treatment using a lens very much like a contact lens implanted in the eye. The lens is placed behind the cornea in front of the iris like the Verisyse Lens or behind the iris like the Visian Lens ( Staar Surgical Co. Inc) to correct for moderate to high amounts of nearsightedness (myopia) and astigmatism. Low amounts of farsightedness can be corrected if the patient is over 40 and experiencing near vision problems from presbyopia (hardening of the lens in the eye).
Intraocular lens implants are excellent for people who either are not candidates for Lasik/ PRK, those who would rather not have those procedures for one reason or another, have thin corneas, deep set eyes or have very strong prescriptions or irregular corneas. There is no need to take out the normal crystalline lens in that this is not cataract surgery. These lenses are removable, the procedure is enhanceable and they contain a 100% ultraviolet blocker.
While phakic lenses appear to be efficacious in the correction of farsightedness surgeons are being more selective in these patients due to anatomical considerations of the farsighted eye. The Farsighted eye is smaller than a nearsighted eye and in some cases there isn't enough room for the implant. This for the time being will likely limit the number of farsighted patients who can benefit from Phakic lens implants.
The FDA has approved a limited number of lenses for vision correction. These lenses are safe and effective and have been used in Europe for over 30 years. Our lens of choice is the Visian Lens. The Visian Lens is made of collagen as opposed to the plastic Verisyse lens and is more of a natural substance to the body, since the Visian Lens is foldable a smaller incision is needed then for the harder Verisyse Lens, surgery time for the Vesian Lens is quicker and it can correct for higher amounts of correction then the Verisyse Lens.
Both lens designs are FDA approved for distance correction up to minus 20 diopters of nearsightedness. Moderate amounts of astigmatism is correctable with phakic lens implantation using toric implants and are working well. The astigmatism that is not correctable with toric implants can be corrected with adjunct procedures including laser as used in Lasik and limbal relaxation incisions on the cornea. In general there is an overall patient satisfaction of 91% with the use of these lens implants. The procedures are reversible. Recent data on the Visian Lens reports after 3 years post-operative 95% of the patients saw 20/40 or better uncorrected, 59% were 20/20 uncorrected or better. This select group of patients was correctable to 20/20 before the surgery.
Lens Implants (RL)
Cataract Surgery: Laser or Lens Implant?
Laser Cataract Surgery For years the notion of patients has been that cataract surgery was done with a laser. Life was simple when I could say; "No it is sound waves that emulsify the lens." Those days seem to be coming to an end with the introduction of the Femtosecond Laser for cataract surgery. Lens Sx Lasers Inc. has recently initiated clinical trails on the Femtosecond laser to perform cataract surgey. The laser will make the incision as well as liquify, soften and breakup the hard clioudy lens in the eye. This is still in the early stages but technology moves today like the speed of sound. Thus the surgeon to shift the age old manual multi-step outdated cataract procedure to one laser with surgeon controlled precision!
Focusing Lens Implant Cataract Surgery
The first approval for focusing lens implants was in November 2003 to Eyeonics' Crysta Lens. Imagine an implanted lens that changes shape and focuses in the eye for clear distance and near vision. The procedure is the same procedure for standard for cataract surgery. The difference is in the lens implant. In the old days cataract surgery was done with a lens implant of fixed power for distance vision and after surgery the patient wore glasses for any uncorrected distance vision and definately for reading. To correct myself in the old old days cataract surgery was done without implants and the patinet wore thick unsightly coke bottle glasses. Now we have lens implants that actually forcus for all distances. They are the Crytalens, ReStor Lens, and the Teenis Multifocal IOL (formerly the ReZoom Lens). These lenses have the ability give good vision at all distances although it's often necessary to wear eyeglasses for certain tasks. In the case of the Crysta Lensit's the only true accommodating Intraocular lens there is a flexible haptic at each end that can move slightly front to back creating a focusing effect for clear distance, intermediate and near vision with minimal if any need for prescription eyeglasses
Refractive Lensectomy (RL) corrects nearsightedness or farsightedness by replacing the natural lens in the eye with an artificial lens implant. The lens implant has a calculated power to replace the lens in the eye. Basically this is the same procedure as the tried and proven cataract surgery that has been successfully performed untold times over the past fifty years. In the case of cataract surgery the surgeon takes out a lens that is cloudy and replaces it with a focusing lens implant. RL is also the procedure of choice for patients without cataract who want better vision and our not candidates for Laser Vision surgery due to thin corneas, very high prescriptions, fear of laser surgery, dry eye or deep set eyes. RL can be combined with other refractive procedures like Lasik, PRK, and CK, to enhance the final outcome.
As a result of RL ones dependency on glasses can be eliminated or their dependency reduced. People who are candidates for the procedure are those who:
- Need cataract surgery and want to reduce or eliminate their dependence on eyeglasses
- Do not want or may not be a candidate for Laser vision correction
- Have very high refractive errors
- Thin corneas and not a candidate for Lasik / Laser vision surgery
Like any other surgical procedure there are risks. Complications with RL are rare. It is a safe, effective and permanent procedure. After RL you will have reasonably good to excellent distance vision but may need reading glasses for some near tasks. The advent of accommodating lens implants such as the Crystalens, ReZoom Lens and the ReStore Lens is helping to achieve near normal vision with no to minimal dependency on eyeglasses. Moderate amounts of astigmatism may require additional refractive procedures performed after RL.