The fear that a contact lens has slipped out of sight and is migrating to an unreachable space behind the eye is common among wearers. This worry often intensifies when a lens feels lost or causes unexpected irritation. While the feeling of a displaced lens can be alarming and uncomfortable, the possibility of a contact lens becoming permanently lodged behind the eyeball is anatomically impossible. This physical reality is due to the eye’s natural protective structures, which effectively seal off the back of the socket.
The Physical Impossibility
The reason a contact lens cannot get stuck behind your eye lies in a continuous, protective membrane called the conjunctiva. This thin, clear tissue covers the white part of the eye, known as the sclera, and then folds back to line the inner surface of the eyelids. This structure creates a physical barrier, similar to a sealed pocket, which ensures that nothing can pass from the front of the eye into the space behind the eyeball.
The fold where the conjunctiva transitions from the eyelid to the eyeball is called the conjunctival fornix. This crease acts as a terminal barrier, meaning any foreign object, including a contact lens, can only travel as far as this fold. Even if a lens moves completely off the cornea and slides under an eyelid, this anatomical seal prevents it from going any further.
Where Displaced Lenses Actually Go
When a contact lens seems to have vanished, it has simply moved from its central position on the cornea, not disappeared behind the eye. The sensation of a lost lens often occurs when it becomes dislodged and shifts into the deepest part of the conjunctival pocket, either high up under the upper eyelid or deep within the lower eyelid sac. This displacement is frequently caused by rubbing the eyes, which can cause the lens to fold in half, or by having eyes that are too dry, causing the lens to stick to the eye’s surface.
A lens lodged in the upper fornix, under the top eyelid, is the most common reason people believe the lens is lost. In this position, the lens is completely out of sight and can cause significant irritation. Even in rare cases where multiple lenses have been retained, they were found clumped together in this deep pocket, not behind the eye itself. The lens is simply hidden by the eyelid tissue, making it feel like it has migrated to an unreachable location.
Step-by-Step Safe Removal
The first and most important step in retrieving a displaced lens is to thoroughly wash your hands with soap and water to prevent transferring any bacteria or impurities into the eye. Next, you should lubricate the eye by applying a few drops of sterile saline solution or contact lens rewetting drops. This helps rehydrate the lens and allows it to move more freely. Do not use tap water or contact lens solution for this lubrication.
After lubricating the eye, use a mirror to help locate the lens, gently pulling down the lower eyelid to check the bottom fornix. If the lens is not visible, look in the opposite direction of where you suspect the lens is stuck. For instance, if you think it is under the upper lid, look down. This action can help encourage the lens to slide down into a visible area. If the lens remains hidden, close your eye and gently massage your eyelid in a circular motion to shift the lens toward the center of the eye.
If the lens moves back onto the white of the eye, you can gently slide it down to the lower part of the eye before pinching it out with your thumb and forefinger. However, if the eye becomes excessively red, painful, or you are unable to locate or remove the lens after several attempts, you should stop and contact an optometrist or ophthalmologist. Seeking professional help is the safest course of action to ensure the lens is removed without causing damage to the eye’s surface.