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Platinum Contact Lens Care for Corneal Grafts - Vision Camberwell
Richard Vojlay Associate Professor (Melb Uni) BSc Optom, LOSc, FACO, PostgradCertOcTher, Dip Humanities (Music)
Dr Laura Downie BOptom, PhD(Melb), FACO, PostgradCertOcTher, Dip Mus(Prac), AMusA
Xianyi (Shay) Zhang BOptom (Melb) Therapeutically Endorsed
Dr. Jaelyn McComas Bach Science (Geog), Doctor of Optometry (Canada), Primary Care Resident (IUSO), FAAO
Contact lenses for corneal grafts.
Corneal grafting or corneal transplantation is the replacement of defective host corneal tissue with donor corneal tissue.
Advanced keratoconus is the most common reason for a corneal graft. A corneal graft is required once the vision deteriorates significantly or a contact lens can no longer be fitted to the irregular cornea.
The majority of corneal grafts are full thickness; all tissue is replaced from the epithelium (top layer) to the endothelium (inside layer). The grafted tissue is held in place by sutures (stitches) which can either be individual or continuous.
It is impossible to predict the quality of vision when the sutures are still in place; however, often vision is moderately to substantially better than unaided vision pre-graft. The sutures are usually kept in place for 12 to 18 months and then gradually removed at the discretion of the corneal surgeon, depending on the shape of the graft. Once the sutures are removed the graft shape may change considerably due to balancing of stresses between the graft thickness and the host corneal thickness. If the patient has good vision with the sutures still in place, there is a reasonable chance that they will have good vision following the removal of the sutures. However the majority of corneal grafts have significant astigmatism on removal of the sutures.
small number of patients Approximately 20% of patients with corneal grafts can manage without any optical correction. Of 30% of patients with corneal grafts require a spectacle correction. 50% of patients with corneal grafts require a contact lens correction. Some patients your with low levels of astigmatism may be able to successfully wear soft contact lenses. Soft contact lenses may also be an option if there is a substantial difference in prescription between the grafted eye and the fellow eye. Usually rigid gas permeable lenses cause fewer complications than soft contact lenses. Your consulting optometrist will advise you if soft contact lenses are an option for you.
Corneal grafts with irregular astigmatism will require rigid gas permeable (RGP) contact lenses to provide good quality vision. Patients who have successfully worn RGP lenses previously will usually prefer to resume RGP wear as they are familiar with the handling and cleaning regime of RGP lenses.
Rigid Gas Permeable Lenses for Corneal Grafts.
Rigid gas permeable (RGP) contact lenses improve vision in the same way as they do in keratoconus. Placing a smooth rigid surface over the cornea allows the tears to fill in the space between the rigid surface and the corneal irregularity, this neutralises 90% of the corneal distortion. The substantial reduction in image distortion gives better definition and contrast, reduced ghosting and consequently much clearer vision.
RGP contact lenses for corneal grafts are available in a significant variation of designs. Unfortunately no one design can be guaranteed to be successful in comfort, vision or stability.
A significant factor in determining the shape of an RGP lens for a corneal graft is the degree of elevation of the graft above the host cornea. Corneal grafts are designed to be slightly large for the aperture of the host cornea and so tend to be slightly elevated; however in some cases the elevation can be substantial. This can substantially complicate the design of the RGP lens as the RGP contact lens has to be specially curved to prevent it being dislodged.
Long-standing corneal grafts can sag and also develop significant elevation.
There have now been significant improvements in the ability for contact lens manufacturers to produce RGP contact lens with very complex designs to accommodate irregular corneal grafts. Diameters can vary from 9 mm up to 11.5 mm. Often the main difficulty will be to find a lens design that will be stable on the corneal graft.
It is impossible to predict who will be successful and able to adapt to RGP lenses at an initial RGP fitting. Occasionally lenses that have an excellent fitting will still be unsuccessful due to the patient's highly sensitive cornea.
It may require a 1 or 2 visits to arrive at an initial contact lens design that can be ordered. Even with an experienced contact lens expert it can take numerous visits to alter the RGP lens fitting to an acceptable level.
Completing the recommended cleaning regime is very important to achieve and maintain successful RGP lens wear. RGP lenses may last up to 2 years or more depending on individual circumstances.
Larger Diameter Rigid Gas Permeable Lenses for corneal grafts.
Advanced computer programs and digital lathes have facilitated the development of complicated larger diameter RGP lens designs. These lenses have the advantage of improved comfort, better centration and a larger area of vision. These designs are at the forefront of RGP contact lens technology. These lenses require the same maintenance and handling as standard RGP lenses, but occasionally can be more difficult to insert and remove due to the larger diameter (13.0 mm to 15.8 mm).
Miniscleral Lenses for corneal grafts.
Miniscleral lenses are also manufactured in a rigid gas permeable material but fit the eye in quite a different way. These lenses are much larger (usually 16.5 mm diameter) and vault the whole cornea, resting on the white part of the eye. Miniscleral lenses rest behind the upper and lower eyelids and as the lids are not hitting the edges of the lens, the lenses are very comfortable. The lenses totally seal on the white part of the eye and cannot be dislodged making them ideal for dusty environments and for active sports where conventional RGP lenses may be dislodged. Miniscleral lenses require the same maintenance and cleaning regime as RGP lenses. Miniscleral lenses can be more difficult to insert as they need to be inserted full of solution and more difficult to remove due to the large diameter.
Hybrid Lenses for corneal grafts.
Hybrid lenses have a hard RGP centre with soft plastic on the periphery. Hybrid lenses have so far have been unsuccessful in fitting corneal grafts, however there are ongoing developments in materials and designs. Hopefully Hybrid contact lenses will become available in the near future.
Quality of vision with contact lenses.
Despite almost all of the corneal irregularity being neutralised by the RGP or hybrid contact lens, there may still be some residual distortion or shadowing of the vision. In most cases this is insignificant, but occasionally there can be a substantial improvement in the quality of vision by wearing spectacles over the contact lenses. Spectacles for use over contact lenses are not covered under the Platinum Plan.
Successful contact lens wear for corneal grafts.
Unfortunately despite the practitioners and patients best efforts, a contact lens fitting may be unsuccessful. This may occur despite an excellent contact lens fitting and can simply be due to intolerance.
All contact lenses that we order have a warranty ranging from three to six months. Some of our manufacturers limit the number of warranty exchanges that are allowed within this warranty period. These restrictions can reduce the likelihood of ultimate success. Success meaning contact lenses that can be worn all day with good comfort, excellent vision, good stability and clear eyes.
Platinum Contact Lens Care for corneal grafts.
As indicated above it can be impossible to predict the success of any lens fitted for corneal grafts. Even contact lenses that have an excellent fitting can still be unsuccessful due to intolerance or difficulty handling the contact lenses. These issues may not be evident during the warranty period as ordering warranty exchange contact lenses and adapting to a new design can take some time. Sometimes even arranging an appropriate review appointment can restrict our ability to resolve contact lens design issues within the warranty period. This is no one's fault; however our role is to prescribe successful contact lenses.
Platinum Contact Lens Care for corneal grafts removes the limit on the number of exchanges or designs that can occur to refine a contact lens fitting and increases the warranty period to 12 months. Within this period we guarantee to successfully fit a design of contact lenses to the best of our ability within the limits of individual patient sensitivities.
Success meaning contact lenses that can be worn all day with good comfort, excellent vision, good stability and clear eyes. This will allow us to swap from small diameter RGP contact lenses to larger diameter RGP lenses to miniscleral lenses to solve problems as they arise. This removes the difficulty that inevitably occurs once the warranty limit has been reached and comfortable all day contact lens wear has yet to be achieved. It also liberates us, the practitioners, to be able to provide the best contact lenses that we can.
Platinum Contact Lens Care for corneal grafts removes the uncertainty of choosing an initial contact lens design and significantly improves the likelihood of successfully wearing contact lenses.
The Platinum Contact Lens Care should be selected in consultation with your contact lens practitioner and is strongly recommended if you have previously been unsuccessful with contact lenses or need to wear contact lenses following your corneal graft. The Platinum Contact Lens Care plan needs to be selected before contact lenses are fitted or prescribed.
The cost of the Platinum Contact Lens Care is $3,000 for lenses for both eyes and $1,500 for a lens for one eye. The Platinum Contact Lens Care plan needs to be paid in full at the initial contact lens fitting.
· The Platinum Contact Lens Care period lasts for 12 months and commences at the first contact lens fitting consultation.
· All contact lenses ordered under our Platinum Contact Lens Care Plan are covered for breakage but not for loss during the warranty period.
· During the Platinum Contact Lens Care warranty period all accessories (such as ocular lubricant drops, lens applicators) and contact lens solutions are included in the cost.
Platinum Contact Lens Care sets a new benchmark for corneal graft contact lens care in Australia.
Consultation Fees for contact lens fitting for corneal grafts.
A Medicare fee is still applicable for the consultations and we can establish Medicare eligibility at your first contact lens fitting consultation.
Fees for slit lamp digital photography ($59) and corneal mapping ($59) and comprehensive OCT contact lens scans ($126) will still apply at the initial consultation.
There will be no further out-of-pocket costs regarding consultations for the remainder of the Platinum Contact Lens Care period with no restriction on the number of consultations.
Using our HICAPS system we can claim for your Medicare rebate directly. To process your Medicare rebate we need a current Medicare card and EFTPOS card to be able to deposit the Medicare rebate into your account.
Medicare does not cover the cost of contact lenses.
Private Health Cover for contact lenses.
Private Health Cover with Extras will usually provide a rebate for contact lenses depending on the level of cover. The range of rebate can vary from $80-$300 depending on the Private Health Fund. Claims are usually limited to once per year and usually apply for each calendar year. Please check with your Private Health Fund to determine your level of cover. Using our HICAPS system we can claim for your rebate directly from your Private Health Fund provided you have your membership swipe card.
Our Practitioners.
At Vision Camberwell we have experienced optometrists prescribing specialty lenses for keratoconus.
Associate Prof Richard Vojlay presents lectures and seminars at the Department of Optometry & Vision Sciences at The University of Melbourne in fitting specialty contact lenses for patients with keratoconus and corneal grafts. In 2000 he assisted in establishing Keratoconus Australia, the first non-profit support group for people in Australia who have keratoconus and continues to act as optometric advisor for Keratoconus Australia. In 2011 in association with the Keratoconus Australia, he assisted in establishing a keratoconus clinic at The University of Melbourne Eyecare Practice. This clinic will allow students to gain more experience in fitting contact lenses for keratoconus. He is the senior supervisor at the keratoconus clinic.
Dr. Laura Downie has specialized in contact lens practice, in particular for keratoconus and corneal grafts, since completing a combined Bachelor of Optometry/Diploma of Music at The University of Melbourne in 2003. In 2008, Dr Downie was conferred her PhD and she has been involved in the undergraduate contact lens teaching program at The Department of Optometry & Vision Sciences, The University of Melbourne since 2004. Dr Downie has also assisted Associate Prof Richard Vojlay with practical seminars for the final year optometry students in contact lens fitting for keratoconus and also supervises at the keratoconus clinic at The University of Melbourne Eyecare Practice. She has lectured on the topic of specialty contact lens fitting at local, interstate and international conferences and has published several first-author papers in peer-reviewed scientific journals.
Associate Prof Richard Vojlay and Dr. Laura Downie have also presented specialty contact lens teaching programs to qualified optometrists at the Australian College of the Optometry.