Article Date: 1/1/2004

contact lens management
Comfort is Paramount

Multipurpose solutions increase patient comfort -- and thus retention.

Comfort and convenience are the focus for contact lens wearers. Approximately 10% of contact lens wearers stop wearing their lenses because of discomfort and/or inconvenience. The introduction of multi-purpose solutions (MPSs) has improved the ease and convenience of contact lens care.

What's so great about MPSs?

All MPSs contain antimicrobial agents that meet disinfection standards set by the FDA. Most also incorporate surface active agents, or "surfactants," to help remove deposits from the lenses that could irritate sensitive ocular tissues.

Because these surfactants have a hydrophobic segment that can bind to the lens and a hydrophilic "tail" that can bind water molecules in the vicinity of the lens, they can also increase the "wettability," and potentially the comfort, of the lens.

AMO's solution incorporates a surfactant and two demulcents.

Moisture + two

However, not all MPSs are alike. Complete MoisturePLUS (AMO Inc.) doesn't rely on its surfactant alone for wearer comfort. It contains two additional comfort agents, propylene glycol and hydroxypropyl methylcellulose (HPMC), both of which the FDA classifies as demulcents. Artificial tears use these to combat dry eye symptoms. Complete MoisturePLUS is the only MPS on the market to contain such ingredients.

Propylene glycol is a small molecule with high, water-binding capacity. It enters the lens matrix, pulling water with it, to hydrate the lens. This improves wettability and lens comfort.

HPMC is a large molecule that produces a long-lasting fluid layer on hydrogel lenses. This helps increase the comfort of the lens/eye interface and maintains lens hydration. In a clinical study comparing multi-purpose solutions with and without HPMC, Complete brand MPS with HPMC received significantly higher comfort and preference scores than those solutions without HPMC.

Additionally, Complete MoisturePLUS contains taurine as a buffering agent. Taurine is the most common amino acid in the tears of normal adults and is found in a number of ocular tissues (though the precise function of taurine at the ocular surface is not known). In a clinical trial, the use of Complete MoisturePLUS resulted in 12% fewer symptoms of clinically significant discomfort than a leading MPS.

Keep up with your patients

It's important that we be aware of the lens care regimens that our patients follow. By including a notation in the chart on the lens solution prescribed, you have the opportunity to follow up with patients at later visits to determine if their lens care regimen is appropriate for them.

Are patients using the recommended solutions, or have they switched to other solutions that are less costly (such as generics) or more convenient for them to purchase (e.g., available at the local grocery store)? Are lenses still comfortable at the end of the day? Might changes in solution use be affecting the comfort of their lens wear?

Don't underestimate comfort

Lens wear comfort is an integral component in creating a satisfied contact lens patient. We need to be as active in prescribing the contact lens solution as they are in fitting the lenses themselves, thus increasing patient retention. Remember, the contact lens is the vehicle for the contact lens solution.

References available on request.



Optometric Management, Issue: January 2004