Contact lenses rely on hydration to remain soft, flexible, and safe for wear. Contact lens solution keeps the lens material hydrated and disinfects it against microorganisms. When a lens is left exposed to air, the absence of solution quickly compromises both the material integrity and the hygienic condition. This lapse introduces significant risks to eye health.
How Lens Material Changes When Dry
Soft contact lenses rely on water content to maintain their proper shape and texture. Exposure to air outside the storage case causes rapid dehydration and a dramatic physical transformation. This loss of moisture causes the lens to shrink substantially, shriveling into a hard, brittle disc.
The brittle state makes the lens susceptible to damage, and handling it can cause microscopic cracks or visible tears. Severe dehydration and physical stress can cause permanent warping, even if the lens is rehydrated. A warped lens will not sit correctly on the eye, leading to discomfort, irritation, and blurred vision.
Increased Risk of Bacterial Contamination
Leaving a lens out of its designated solution eliminates the disinfection process performed during storage. The multipurpose solution contains agents specifically formulated to kill or inhibit the growth of bacteria, fungi, and other microbes. Without this protective environment, the lens is exposed to a variety of airborne contaminants, including dust, dirt, and microorganisms.
A dried lens is no longer considered sterile and can harbor bacteria that are commonly found on skin or in the environment. If a contaminated lens is placed in the eye, it can introduce these pathogens directly to the corneal surface. This contamination significantly elevates the risk of severe eye infections, including microbial keratitis, which is an inflammation of the cornea that can lead to pain, vision loss, or in rare cases, permanent blindness.
Steps for Safe Rehydration and Inspection
Rehydration Process
If a lens is found dried out, the first step is to place it immediately into a clean lens case filled with fresh, sterile contact lens solution. It is imperative to never use tap water, saliva, or any other liquid, as these contain microbes that can cause sight-threatening infections. The lens must be allowed to soak for six to twenty-four hours to ensure full rehydration and disinfection.
Visual Inspection
After the soaking period, a mandatory visual inspection must be performed before handling the lens further. The lens should be carefully examined for any signs of damage, such as small tears along the edge, surface scratches, or any cloudiness or discoloration. If the lens appears compromised, it must be discarded immediately, as a damaged lens can scratch the cornea upon insertion.
Wearing Assessment
If the lens appears perfectly intact, it should be gently rubbed and rinsed with fresh solution before attempting to wear it. Upon insertion, if the rehydrated lens feels even slightly uncomfortable, stiff, or different from a fresh lens, it must be removed and thrown away. The cost of replacing a single lens is negligible compared to the health risk required for a serious eye infection.