REFITTING WITH GP LENSES
Refitting Soft Lens Patients With GP Lenses
Consider GP lenses for your patients when soft lenses don't make the grade.
By Edward S. Bennett, OD, MSEd, and Robert L. Davis, OD, FAAO
Most practitioners know about the eye health and vision benefits that gas permeable (GP) lenses provide, including for presbyopic correction and irregular and post-surgical cornea visual correction. In addition, GP wearers seem more inclined to perceive their lenses as healthcare devices that are custom designed and manufactured for their eyes. This modality is also not as readily available from alternative distribution suppliers.
Another important application of GP contact lenses -- and an underused one -- is for refitting problematic soft lens-wearing patients. There exists a large group of soft lens wearers who may greatly appreciate the vision and eye health provided by GP lenses but are not given the option to compare. Instead, their practitioners refit them into different types of soft lenses, often resulting in the same symptoms, without giving patients the opportunity to try a modality that would likely reduce or eliminate their symptoms. Is this fair to patients who deserve the opportunity to improve their quality of life?
Who Should You Refit Into GPs?
Obviously, soft lens patients who are asymptomatic and exhibit no clinical signs of compromise should stay in soft lenses, just as you should not refit satisfied GP wearers into soft lenses. However, the following five types of patients represent those who benefit when you refit them from soft lenses into GP lenses:
1. Patients Who Have Critical Distance Vision Demands Patients who need optimum distance vision for their occupational responsibilities as well as for night driving would likely benefit from GPs. Many soft lens patients complain about poor vision at night, which results from the lens's water-based composition and tendency to develop deposits. When patients view headlights and streetlights through a soft lens they may see halos and streaks of light emanating from the light source, which sometimes prompts them to discontinue wearing soft contact lenses in favor of spectacles when driving at night. The optical quality of GP surfaces often eliminates these symptoms.
2. Astigmatic Patients Many low (0.50D to 1.00D) refractive astigmatic patients who wear spherical or toric soft lenses are not satisfied with their vision. With spherical lenses, their vision is not as crisp because of the uncorrected cylinder; with soft toric lenses, patients may not achieve a stable fit, even after trying several different types of soft toric lenses. Such patients often react positively when they try GP lenses in their prescription. Unfortunately, in many cases their practitioners never consider GP lenses and instead subject these patients to multiple soft lens fits.
Many high (>2.00D) refractive astigmatic patients who wear soft toric lenses experience visual symptoms because lens rotation compromises their vision. Practitioners should avoid the temptation to force soft toric lenses on such patients, because they usually succeed with GP lenses.
3. Presbyopic Patients From a visual standpoint, we strongly recommend GP multifocals to presbyopic patients who want contact lens correction. However, we do trial fit soft multifocal designs initially if a patient wants to try them. It's common for patients to switch to a GP multifocal because of compromised vision with soft lens designs.
4. Athletes GP lenses can improve visual quality and reduce glare and other visual symptoms from lights during sports activities. For example, patient CS is a varsity sport volleyball player who presented in Dr. Davis's office with 20/20 vision monocularly and complained of intermittent doubling of vision and glare from lights while wearing soft spherical lenses. The lens drying out on the eye caused the presumed doubling or hazing of vision. Dr. Davis refit CS into a large diameter GP lens that improved acuity, eliminated the vision doubling or haziness and provided comfort comparable to the soft lenses.
5. Patients Who Have Compromised Eye Health Even though disposable lenses are popular and have reduced deposit-induced complications, ocular inflammation with soft lenses is more common than with GPs. Hydrophilic lenses age as wearing time increases, causing deposit buildup and lens dehydration. As the tears evaporate, the lens tightens on the eye and traps debris, increasing risk of ocular inflammation. Contact lens-induced papillary conjunctivitis, vascularization, infiltrates and ulcerative keratitis may result in a reduced wearing schedule if not discontinuation of lens wear. Patients who have these conditions may especially appreciate GP lenses.
Soft-to-GP Fitting Pearls
1. Remember that patients look to us for guidance. If we feel that GP lenses are in their best interest, patients will often agree.
2. Use terms such as "lens awareness" and "lid-to-edge sensation" when presenting GP adaptation.
3. Use a topical anesthetic before the initial application to optimize a patient's initial experience.
4. Whenever possible, make the initial lenses in a patient's prescription so he can experience good vision initially.
5. Use large diameter, ultrathin lens designs to optimize initial comfort and reduce adaptation time.
Always remember that patients typically respect your judgment about what contact lens material is best for them. Even if patients have preconceived ideas about initial comfort, most patients will try GP lenses if you feel that this modality will provide better vision and eye health. Although you should tell patients that more "initial awareness" occurs with GP lenses because they are smaller and move more with each blink, you should also assure patients that they should adapt to GP lenses.
If patients are initially apprehensive, use a topical anesthetic before the initial GP application. This makes the initial experience positive because these patients are concerned most about the initial sensation. It also allows you to assess the fitting relationship sooner and more accurately.
Use ultrathin designs and larger diameters to optimize comfort. Ultrathin designs also reduce lens mass, which results in less inferior decentration and corneal desiccation.
Just as important with a soft-to-GP wearer is that they immediately experience excellent vision, which is the primary benefit of GP lenses. Whenever possible, make sure the first GP lenses you provide to patients are in their prescription (either via inventory or empirical fitting). Former soft lens patients commonly remark, "I've never seen this well." The initial awareness consideration may lessen once patients notice their improved vision.
Table 1 provides some pearls for refitting soft lens patients with GP lenses.
Give GPs a Try
When soft lenses are not optimal for your patients, stop trying to "put a square peg into a round hole." As contact lens practitioners, we should always fit the best lens for any given patient. Refit your soft lens patients into GP lenses when your patients will benefit and you will reap the rewards that accompany high patient satisfaction.
Dr. Bennett is an associate professor of optometry at the University of Missouri-St. Louis and is executive director of the RGP Lens Institute.
Dr. Davis has an eyecare specialty practice outside Chicago. He is a diplomate of the Cornea and Contact Lens Section of the AAO and a past chair of the Cornea and Contact Lens Section of the AOA.