COST OF SOFT LENS CARE
Rub vs. No Rub: What Are the Costs?
This study compared the price, time and
solution volume required for four multi-purpose solutions that have no-rub approval.
By Christopher Johnson, Nathan Kohler, Bruce
Bean, Patrick Caroline,
FCLSA, FAAO, and Jennifer Smythe OD, MS
Historically, proper soft lens care and disinfection has required that patients perform three steps: cleaning, rinsing and disinfecting. Recently, a growing number of lens care products have received Food and Drug Administration (FDA) approval for use as "no-rub" disinfection regimens.
To properly instruct patients how to use these products, we need a clear understanding of the new nomenclature that surrounds no-rub systems. Theoretically, there are three possible forms of multi-purpose solution disinfection: the rub and rinse technique, the no-rub technique and what we call the immersion technique.
Rub and Rinse Disinfection This is the traditional form of disinfection in which upon lens removal, patients perform digital, in-the-palm cleaning, usually with a surfactant cleaner or multi-purpose solution. A rinse cycle and storage in disinfection or multipurpose solution follows this step.
No-rub Disinfection The term "no-rub" is misleading, in that many practitioners and patients have mis interpreted it to mean "out of the eye and directly into the solution." Using the product in this manner significantly deviates from the way the FDA approved and labeled the product.
In reality, the term "no-rub" means that a rinsing cycle replaces the traditional in-the-palm cleaning regimen. The number of required rinsing cycles and length of rinsing time varies between manufacturers and can cause confusion for both patients and practitioners on the appropriate use of the products.
Immersion Disinfection Today, immersion is only a theoretical mode of disinfection in which the product could disinfect lenses by simple immersion into the solution. In other words, patients would directly place the lenses into the disinfection solution upon lens removal without any rubbing or rinsing maneuvers. Currently, no lens care regimen has been approved for immersion disinfection.
This mode of disinfection is often inappropriately called stand alone disinfection. The FDA uses the term "stand alone" to describe a specific test used as part of the process required to obtain a no-rub indication.
Methods
This study evaluated the annual volume, time and cost requirements for patient use of four currently marketed "no-rub" disinfection solutions. The four products we evaluated were:
- Allergan Complete
- Alcon Opti-Free Express
- Bausch & Lomb ReNu MultiPlus
- CIBA Vision AOSept Clear Care
*At the time of this study, CIBA Vision Solo Care had not obtained FDA approval as a no-rub product.
To evaluate the objective measurements of volume, time and cost, we followed the lens care instructions as outlined in the individual product package inserts. Within the package inserts, the only ambiguous nomenclature was the instruction "rinse thoroughly." After consulting with the FDA, we arbitrarily assigned a rinsing time of five seconds per lens side.
We determined flow rates for each of the four test solutions by spraying solution into a flask on a digital scale for a measured amount of time in seconds. We repeated this procedure multiple times and divided the total volume by the total time to establish a flow rate. Using the flow rate made it possible to extrapolate the amount of solution used in a five-second rinsing period. We also measured how much solution it took to fill the individual lens storage cases as instructed in the package insert.
The following section shows the various product package insert instructions by which we determined the time and solution required to perform both the rub and no-rub modes of disinfection. (CIBA Vision's peroxide-based AOSept Clear Care system does not have a rub indication; therefore, we evaluated only the no-rub mode of disinfection.) The values from our measurements are listed in parentheses.
Package Insert Instructions
Complete
Flow rate = (1.35 ml per second)
Rub (must be used for lenses used for more than 30 days)
- Place three drops of solution on each lens surface and rub each side of lens for 10 seconds. Rinse both lens surfaces thoroughly with solution to remove all debris. (60 seconds)
- Place lenses in case and fill with solution until lenses are fully covered. (2.79ml)
- Prior to re-inserting lenses, rinse thoroughly with fresh solution. (20 seconds)
Total procedure time = (80 seconds)
Total solution used (including case fill) = (56.8 ml)
No Rub
- Thoroughly rinse both sides of the lenses with solution. (20 seconds)
- Place lenses in case filled with solution. (2.79 ml)
- Prior to re-inserting lenses, rinse thoroughly with fresh solution. (20 seconds)
Total procedure time = (40 seconds)
Total solution used (including case fill ) = (56.8 ml)
Opti-Free Express
Flow rate = (1.17 ml per second)
Rub (instructions from no-rub insert *)
- Apply two drops of solution to each lens surface. Rub each side of the lens for about 20 seconds. Be sure to rub each side of the lens. (80 seconds)
- Perform no-rub regimen, which includes morning rinses. (40 seconds)
- Fill case with enough solution to cover lenses. (2.79ml)
Total procedure time = (120 seconds)
Total solution used (including case fill) = (49.6 ml)
No Rub
- Thoroughly rinse each side of the lens for 5 seconds with solution. (20 seconds)
- Fill case with enough solution to cover the lenses. (2.79ml)
- Before wear, rinse each side of the lens for 5 seconds to remove any debris on the lens. (20 seconds)
Total procedure time = (40 seconds)
Total solution used (including case fill) = (49.6 ml)
*The instructions for the No-Rub Opti-Free Express rub method (in the no-rub insert) differ slightly from the instructions in the insert of regular Opti-Free Express. It appears that for simplicity, the no-rub insert instructs the patient to rub for 20 seconds on each side before doing the no-rub method. The regular Opti-Free Express insert states that the last step is to thoroughly rinse both surfaces of the lens with solution until you have removed all traces of debris, instead of rinsing each side for 5 seconds.
ReNu MultiPlus
Flow rate = (1.1 ml per second)
Rub (must be used for lenses used for more than 30 days)
- Place at least three drops of solution on each side of contact lens and rub for 20 seconds. (40 seconds)
- Remove surface debris by rinsing thoroughly with solution. (20 seconds)
- Place cleaned contact lenses in the lens case and fill with fresh solution. (2.79ml)
Total procedure time = (60 seconds)
Total solution used (including case fill) = (24.79 ml)
No Rub
- Thoroughly rinse each side of the lens. (20 seconds)
- Place cleaned contact lens in the lens case and fill with fresh solution. (2.79ml)
Total procedure time = (20 seconds)
Total solution used (including case fill) = (24.79 ml)
AOSept Clear Care
Flow rate = (1.65 ml per second)
No Rub
- Remove your lenses one at a time and place them into the appropriately-marked dome basket holder.
- Thoroughly rinse the lenses for 5 seconds through the basket holder with solution. (5 seconds)
- Fill the lens case with solution to the fill line and place the lens holder in the case. (9.95 ml)(takes approximately 5 seconds)**
Total procedure time = (10 seconds)
Total solution used (including case fill) = (18.2 ml)
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Figure 1. Number of seconds required to perform rub and no-rub disinfection
procedures. |
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Results
Time Required For Lens Care Figure 1 describes the number of seconds required to perform both the rub and no-rub disinfection procedures.
Volume of Solution Required for Lens Care According to the package inserts, the amount of solution required to clean contact lenses varied from manufacturer to manufacturer. However, when comparing a single manufacturer's rub to no-rub procedures, the only significant difference between them was generally the three drops of solution required for rubbing, which we determined to be negligible. Figure 2 summarizes the volume of solution required per year by each manufacturer. If we convert the ml of solution per year into actual bottles (each bottle containing 355 mls of solution), then Complete would require 58 bottles of solution per year, Opti-Free Express 51, ReNu MultiPlus 25 and AOSept Clear Care 19.
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Figure 2. Amount of solution required for lens care per year for both rub and no-rub disinfection procedures.
(AOSept Clear Care is for use as no rub only.) |
Immersion Disinfection The theoretical immersion technique would require only one step for disinfection. The contact lenses would be placed directly into the disinfection solution upon lens removal. The volume of solution required would be the 2.79 ml used to fill the case multiplied by 365 days in the year. This equals 1,018.35ml a year or 2.87 bottles of solution per year!
Cost of Solution
In April 2002 the average retail prices (Portland, Oregon area) of the four study solutions were:
Complete
$7.53 355 ml
Opti-Free Express $7.25 355 ml
ReNu MultiPlus $7.77 355 ml
AOSept Clear Care $8.01 355 ml
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Figure 3. Yearly cost of the various disinfection systems (based on prices in Portland, Oregon area). |
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From these data we can determine the theoretical cost of the various disinfection systems (Figure 3) as follows (the rub costs are omitted since they are the same as the no-rub):
Complete: ($7.53 X 58 bottles) = $436.74 per year or $1.20 per day
Opti-Free Express: ($7.25 X 51 bottles) = $369.75 per year or $1.01 per day
ReNu MultiPlus: ($7.77 X 25 bottles) = $194.25 per year or $0.53 per day
AOSept Clear Care: ($8.01 X 19 bottles) = $152.19 per year or $0.42 per day
Discussion
The FDA requires that solution manufacturers submit their labeling for review and approval prior to release of the product. This ensures that proper instructions are provided to practitioners and patients. All eyecare providers should become familiar with the appropriate techniques for lens cleaning and disinfection as recommended by the solution manufacturer and the FDA. This information is clearly outlined in the products' package inserts and should serve as our guide in providing the patient with proper instructions for lens care and disinfection.
It is unrealistic to think that many of our patients use their lens care products as outlined in the package inserts. Proper patient instruction is ultimately the responsibility of the eyecare professional dispensing the solution. We cannot stress enough the importance of initial patient instruction. If an individual patient elects to deviate from our instructions, it is often beyond the scope of our control. Remember to reinforce the proper cleaning and disinfection techniques at each follow-up visit. Make sure your instructions are clear and that you repeat them to best accomplish this reinforcement. Lack of proper patient education could place the practitioner into a precarious medical/legal situation should the patient develop a contact lens-related complication while improperly using his care products.
The purpose of this study was not to question the effectiveness of the various products on the market, but to compare the time, volume and cost required to properly use each solution. There is considerable variation in flow rates, time required to complete each regimen and total annual cost of "one-bottle" disinfection systems available on the market today. Recognizing these differences is important when recommending the most appropriate lens care regimen for our patients. To rub or not to rub is clearly in the hands of each eyecare professional. Whatever the regimen, it is ultimately the practitioner's responsibility to instruct the patient how to properly use the product. You should always consider the few minutes it takes to accomplish this as time well spent.
Christopher Johnson is a fourth year optometry student and a teaching assistant for the contact lens department at Pacific University .
Nathan Kohler is a fourth year optometry student at Pacific University.
Bruce Bean is a third year optometry student at Pacific University.
Mr. Caroline is an associate professor of optometry at Pacific University and an assistant professor of ophthalmology at the Oregon Health Sciences University.
Dr. Smythe is an Associate Professor of Optometry at the Pacific University College of Optometry and a Diplomate in the Section on Cornea & Contact Lenses of the AAO.