Contact Lens Design & Materials
So Many Choices...Choose the Right Replacement Schedule
BY NEIL PENCE, OD, FAAO
One of the more common dilemmas facing new interns is which of the different frequent replacement soft lenses to select. Rather than detailing their materials and designs, it may be useful to consider how to select a particular lens or lens type.
Let’s review elements of the U.S. Food and Drug Administration’s (FDA) contact lens category clearance process. Marketing clearance letters for frequent replacement lenses list whether daily wear, extended wear up to six nights and seven days, or 30-day continuous wear is allowed. Then, they are cleared as a single-use disposable (replace after each use) or frequent replacement lens (in which case approved cleaning and disinfection is required prior to reapplication). In nearly all cases, the eyecare provider is tasked with determining the appropriate lens replacement schedule.
A review of the package inserts of frequent replacement soft contact lenses finds common wording when it comes to replacement. Daily disposable lenses state that they are indicated for daily disposable wear only. All other lenses will note clearance for perhaps one-week disposable wear and for frequent or planned replacement wear. All include wording to the effect that the practitioner is responsible for determining the appropriate replacement schedule, or that contact lenses should be replaced as recommended by the eyecare professional.
Are practitioners solely on their own in determining the best replacement schedule? Not entirely. Companies can, and do, have recommended replacement times. Some package inserts mention that the lenses are recommended to be replaced every two weeks. The majority of (if not all) lenses recommended by manufacturers for one-month replacement seem to not include a monthly suggestion in the package insert.
While two-week versus one-month replacement is technically not part of the FDA clearance process, it is in fact certainly related to the lens clearance. The clinical studies submitted to gain clearance will generally have used the same replacement schedule that the company ultimately recommends for that product.
Understanding the FDA wear schedule clearances and knowing the manufacturers’ recommended replacement frequency is a very good starting point. That knowledge should help practitioners select the particular lens or lens type that is best for each individual patient—“individual” being the key word here.
Select lenses and lens replacement schedules based on a needs assessment that incorporates patients’ history with lens wear; occupational, recreational, and lifestyle demands; compliance likelihood; and need for convenience. Next, an ocular exam should reveal any previous issues, such as the need for higher-oxygen options, susceptibility to depositing or soiling of lenses, presence and severity of dry eye, giant papillary conjunctivitis-like lid involvement, etc. Using this information, practitioners can then recommend a patient-specific replacement schedule.
If the practitioner-recommended replacement schedule matches a patient’s needs and serves the patient’s best interests, and if the practitioner does a good job of communicating the reason for this recommendation, the likelihood of good compliance on the part of the patient is much higher. Effective recommendations with better compliance should assure greater success for your patients. CLS
Dr. Pence serves as associate dean, Clinical and Patient Services, Indiana University School of Optometry in Bloomington, Ind. He is a consultant or advisor to Alcon, has received educational funding from Alcon, Johnson & Johnson Vision Care, and B+L, and has received travel funding from CooperVision. You can reach him at firstname.lastname@example.org.