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Posts Tagged ‘contact lens’

Recent Hybrid Lens Technology

Saturday, August 28th, 2010

By Rob Davis, O.D., F.A.A.O.

In 2001, Quarter Lambda Technologies (later to become SynergEyes, Inc.) began research and development of a new hybrid contact lens design that ultimately received FDA clearance in 2005. The SynergEyes® hybrid lens differed from the original SoftPerm® design in several key areas. SynergEyes hybrid contact lenses use high oxygen permeable materials and a patented technology called “Hyperbond®” that significantly reduces the separation between the rigid and soft junction of the lens that was common in the SoftPerm® lens. The soft skirt portion incorporates a special surface treatment called ‘HydrolEyes®’ to improve surface wettability and comfort.  In addition, the SynergEyes® lens is available with adjustable soft skirt curves as well as multiple fitting curves allowing for more customized fitting of the lens for virtually any patient in a contact lens practice.

SynergEyes initially developed four hybrid contact lens designs, including the SynergEyes® A lens for patients with astigmatism, the SynergEyes® KC lens for fitting cases of emerging keratoconus and other steep corneas, the SynergEyes® PS lens for fitting post-surgical corneas and other eyes that have flatter corneal surfaces; and the SynergEyes® Multifocal design for patients over 40 who cannot see close up.

In 2010, SynergEyes introduced the ClearKone® design, which fits a much broader range of keratoconus and irregular cornea patients then any other hybrid contact lens products.

The SynergEyes® family of hybrid lenses provides excellent comfort, optimal vision and corneal health. Numerous fitting parameters and the high oxygen permeability of the RGP material eliminates “tight lens syndrome” that can result in edema or swelling of the cornea. The increased amount of tears underneath the lens eliminates friction between the lens and the surface of the cornea giving an added measure of safety and comfort. The improved surface treatment reduces the dryness experienced by other contact lens designs. The improved durability of the rigid/soft junction, base curve availability, and options of skirt radii of the SynergEyes® lens has evolved this technology to the point that it has now entered the mainstream contact lens category for patients with normal corneas as well as irregular corneas.

Read The History of Hybrid Lenses

Contact Lenses vs. Surgery for Keratoconus

Saturday, July 31st, 2010

Contact lenses with a rigid surface are the undisputed gold standard for restoring vision in keratoconus.  Despite recent advances in surgical treatment — including collagen cross-linking, intracorneal ring implants (Intacs), and partial-thickness corneal transplants — none of the currently available surgeries can make the distorted keratoconic cornea quite as smooth as the surface of a rigid contact lens.  The uniform surface of a rigid lens masks the distorted, irregular cornea in keratoconus, allowing light to properly focus into the eye.  Simply put, the rigid surface neutralizes the optical turbulence of the keratoconic eye.  This is why many of the top corneal surgeons first refer their keratoconus patients to a contact lens specialist before operating.  Of course surgical treatment has its place.  However surgery for keratoconus often has a secondary role in relation to less invasive contact lens treatments.

A historical challenge with rigid or “hard” contact lenses is that some wearers, even those without keratoconus, have difficulty overcoming the initial awareness of the lens edge interacting with the eyelid.  If you have keratoconus and can’t wear even optimally prescribed rigid lenses, you may be stuck between a rock and a hard place.  That’s because glasses and corneal surgery by themselves can’t approach the quality of vision afforded by rigid optics, at least not typically.  Furthermore, while soft contacts are initially more comfortable than their rigid counterparts, the soft material conforms to the irregular “peaks and valleys” of the keratoconic cornea, leaving the visual distortions largely unaddressed.

So what can your eye doctor do in the aforementioned situation?  Your doctor may recommend UltraHealth or ClearKone® hybrid contact lenses which combine the clarity of a rigid center with the comfort of a soft outer skirt.  These  lenses were designed specifically for keratoconus.  For selected patients, properly prescribed UltraHealth  lenses can afford a new-found freedom that no other treatment can approach.  UltraHealth  is an important option for some keratoconus patients who are unable to wear rigid lenses.  Yet UltraHealth  also has a role for many other keratoconus patients, especially those active in sports where resistance against lens dislodgement and visual stability are desirable.  Many of the contact lens specialists at the forefront of keratoconus treatment are certified to prescribe UltraHealth.  These contact lens specialists tend to interact regularly with corneal surgeons, using a team-approach to treat keratoconus both non-surgically and surgically as dictated by the particulars of each case.

Another alternative is scleral lenses, which are rigid contacts that are unusually large — larger in diameter than most soft contacts.  Scleral lenses often provide improved initial comfort over smaller diameter rigid lens designs, however they can require greater expertise by the practitioner and patient for successful wear.

For those already wearing more common rigid lenses, but who are experiencing the unavoidable rubbing on the sensitive corneal surface from the lenses, your eye doctor may prescribe a “piggyback” system.  In piggyback systems, breathable soft lenses are worn underneath the rigid lenses not for improving vision, but for protecting against mechanical chaffing and the resulting discomfort.  Your eye care professional can determine the appropriate contact lens modality for your specific circumstance, including whether lens wearing discomfort is due to sensitivity of the lens edges, lens chaffing of the cornea, or some other reason.

Ultimately, the practitioner’s experience and skill are more important than the contact lens design used for treating keratoconus.  Many eye doctors do not routinely prescribe medically-necessary contact lenses and will refer you to one of their colleagues with such expertise.  Since the pattern of corneal distortion in keratoconus is as unique as a fingerprint, there isn’t a single lens design that works for every eye.  Contact lens prescribing for keratoconus is a process which can span many visits before all refinements to the lens parameters are completed.  Due to the chair-time required and custom nature of the prescribing, it’s not uncommon for the services and lenses to cost over $1,500 without third party coverage.  Many medical insurances fail to understand that contact lenses for keratoconus are non-elective and medically-necessary for rehabilitating vision.  Consequently, keratoconus patients often shoulder most of the financial responsibility for their contact lens treatment.

Questions Keratoconus Patients are Asking

Friday, July 30th, 2010

Q: I am a Keratoconus patient and have been wearing Soft Perm contact lens for over 10 years. I have now been fitted with the new ClearKone Synergeyes lens in both eyes. I get great vision with these contacts and comfort for the most part however my contacts cloud up at times, especially my left eye.  I know that these lenses are high in oxgyen – like 7 times more oxygen is received by the conrea compared to the Soft Perm – could this be the adpatation period? Shak

A: Shak, you bring up a very common issue faced by SynergEyes and other contact lens patients: “cloudy vision.”  There are several reasons for cloudy vision including an improper contact lens fit.  Please tell your contact lens fitter about this issue so that he/she can check the fit and make sure that it is correct.   More commonly, many patients experience cloudy vision because of the surface of their lens drying out or hazing over.  The surface of contact lenses requires extreme care in order to keep it wetable.  There are several steps that you may want to take in order to enhance the surface of the lenses.  1. Use the proper soap.  The soap that we use can have oils that cause the surface of the lens to become non-wetting.  Use lanoline free soaps that are free of perfume and fragrances.  2. After washing your hands, rinse your fingertips with the contact lens solution that you use prior to handeling your contact lenses (Unless you use a hydrogen peroxide solution such as Clear Care) 3. If you are getting cloudy vision consider switching to a different contact lens solution that creates a more wettable surface.   As always consult your contact lens fitter on any changes that you make to your lens wearing routine or solution use. Dr. Kading


Q: Since part of the hybrid lens is rigid, will I feel the lens in my eye?

A: If you’ve never worn contact lenses before, or if you have only worn soft lenses, there may be a period of adaptation. Typically this adaptation period lasts for 3-5 days.

Your practitioner may want to build up your wearing time over a few days, and they will be able to recommend a wear schedule customized for you.

Q: I have had keratoconus for 4 years and it continues to get worse.  At what point should I consider surgery?

A: Approximately 20% of patients with keratoconus will have progression to the degree where corneal surgery is necessary.  The most common procedure performed is a full thickness corneal transplant also known as a penetrating keratoplasty (PKP).  In this surgery the diseased cornea is removed and replaced by a human donor cornea.  Luckily, transplantation of the cornea is the most successful of all organ transplants with a low rejection rate.  Many patients will still need the assistance of glasses or contact lenses for optimal vision. This is why many of the top corneal surgeons first refer their keratoconus patients to a contact lens specialist before operating. Answer by: Dr. Chou

Q: I’ve thought about getting Intacs, but I’ve heard that you still need to wear contact lenses after you’ve had Intacs surgery. Is this true?

A: Intacs is a relatively newer surgical method to address the corneal irregularity found in keratoconus. It involves the implantation of tiny plastic segments within the cornea. The result is to make the optical surface of the cornea relatively more regular, thus reducing the degree of vision distortion. This technology is only indicated for keratoconic corneas without scaring, yet have become contact lens intolerant. Results with Intacs have been encouraging, but once again are not a total solution for this disease. As with PK, patients who have had Intacs implanted most often still require contact lens correction for maximum vision. By making the corneal surface more regular contact lens fitting may be more successful following Intacs.

Keratoconus patients contemplating Intacs surgery should first consult with a qualified contact lens practitioner to investigate less invasive and potentially more effective treatment. Click here for an article on surgical options.  Answer by: Dr. Eiden.

Q: What is the best solution to use with my ClearKone® lenses?

A: There are several care systems approved for use with hybrid contact lenses.  You should always follow the instructions provided by your eye care professional with regard to caring for your lenses.  SynergEyes, the manufacturer of ClearKone lenses also has some recommendations that you can find on this website.

Q: Can I sleep in ClearKone® lenses?

A: ClearKone lenses are approved by the FDA for daily wear only.  Therefore you should never sleep in your lenses.   You should remove your lenses at the end of the day clean them and store them overnight.

Q: What do you suggest for dry eyes?

A: Use re-wetting drops approved for soft lenses like Optive to help with dryness.  It is also very important to digitally clean your lenses – ignore the “no rub” on solutions. Also using the non preserved products for insertion does seem to help as well, rather than using a multipurpose solution.

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To submit a question, please send an email to askanexpert@synergeyes.com. We will review all questions and post an answer each week.

Please note: If you have an urgent question about your eye health, contact your eye care practitioner immediately. This page is designed to provide general information about vision, vision care and vision correction. It is not intended to provide medical advice. If you suspect that you have a vision problem or a condition that requires attention, consult with an eye care professional for advice on the treatment of your own specific condition and for your own particular needs.

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