In the early days of Bells palsy, eye care is the most important concern. Maintenance of moisture and protection from debris are important functions that are frequently disrupted with 7th nerve damage. Permanent damage to the cornea is a risk if care is not taken to protect the eye. Acoustic neuroma patients may also encounter corneal dryness after surgery, even when the facial nerve remains intact.
CAUSE OF THE DRY EYE
The dry eye and the associated problems are caused by a combination of things. For some people the tear gland may not be producing moisture. Blinking is the mechanism that protects the eye from external debris and spreads tears over the cornea. Under normal circumstances we blink every 5-7 seconds. With every blink the eyelid spreads moisture over the cornea. With facial paralysis the ability to blink may be disrupted. Eyelid closure can be weak or the eye can be stuck wide open.
Take action if the eye feels uncomfortable. A stinging or burning sensation can mean the eye is too dry, even if tears are apparent. The 7th nerve does not control focus, so if you are experiencing blurred vision, don't ignore it. It may be a warning of a dry cornea that needs to be protected.
For many, although the lacrimal gland produces tears, without a blink the tears cannot coat the eye. The eye may appear to be tearing excessively. It actually only seems that way because the tears are not being spread over eye, but instead are collecting in the limp lower lid or running out of the eye. Or, the eye may tear excessively, especially while chewing. We refer to this as "Crocodile Tears". Crocodile tears can occur from the onset of Bell's palsy, or can develop during recovery.
PROTECTING THE EYE
Manually blink your eye using the back of your finger at regular intervals, and especially when it feels dry.
In some cases all that is needed for extra help maintaining moisture during the day is artificial tears. Look for a brand that is labeled "for sensitive eyes", "non-allergic", or "preservative free", etc. Thimerosal is a preservative that can be particularly irritating. Eye-drops don't last long, and are not the solution for everyone.
Bion Tears is a commonly used brand.
GenTeal uses a natural preservative, which makes it more comfortable for many people. It does the job well.
Tears Naturale has the same active ingredient as Gen-Teal. It's available with a preservative similar to GenTeal, as well as preservative-free (Tears Naturale Free).
Celluvisc is thicker than Tears Naturale, and will afford excellent lubrication. However, it is costly, and because of its high viscosity, vision may not be as clear as with Tears Naturale or Gen-Teal. For additional moisture retention, as well as protection from wind and debris, try a patch.
A moisture chamber will provide the same, or better protection than a patch, but is clear to allow better vision. One type is very much like goggles designed for just one eye, and it works well. If it becomes foggy due to the tight seal, a tiny pinhole will solve the problem. Your ophthalmologist should be able to provide you with the patch. There are also moisture chambers that clip onto eyeglasses.
The examples shown are (top) Eagle Vision, Inc.'s "Rectangular Moist Eye Moisture Panel" and (bottom) Franel Optical Supply's "Moisture Chamber". These items can not be purchased directly from the manufacturer by the patient, but can be purchased by an opthalmologist for your use. As an alternative to a moisture chamber you can make your own patch with plastic wrap over your eye, and taped to your face. Surgical tape will be gentler for your skin and easier to remove than other types. Vaseline can also be used to hold it in place.
Wraparound sunglasses or swimming goggles are other helpful alternatives to a moisture chamber.
For nighttime protection if your eye will not close, lubricants (gels & ointments), or lubricants combined with a patch are a good solution. Gels are thicker than artificial tears due to the addition of mineral oil. The consistency is very much like Vaseline. By adding a "pirate's patch", you not only add protection from debris and injury, you also keep light out and may find it easier to fall asleep. If you use a pirate's patch, think about using a plastic wrap patch beneath it for added protection if the patch shifts, or create your own dark patch. Franel Optical Supply makes a "Peel-n-Press Occluder" that should eliminate the problem of the patch shifting during the night.
Lacrilube, ViscoTears and HypoTears are gels for nighttime protection.
Refresh PM is an option if a bit less protection is needed. Its thinner consistency makes it easier and more pleasant to wake up with.
Gels and ointments can be used during the day for more lubrication than eye-drops provide. However, because they are thick, vision can be blurry.
The eye can be taped closed at night, but a note of caution is appropriate. It is too often suggested to patients without proper instructions. If not done correctly the eyelid can easily pop open, exposing the eye to worse damage than without the tape. Make sure to use a gentle, non-abrasive and easily removed tape (such as paper surgical tape), and learn the correct way to apply it.
If stinging or burning occurs with any of the gels or drops, you may be sensitive to one of the components. Try other brands, and if that doesn't help, see your ophthalmologist for further help - Never ignore symptoms of a dry eye!
WHEN GELS & PATCHES AREN'T ENOUGH
Consider a visit to an ophthalmologist, even if you believe you can manage eye care on your own. There is no a substitute for professional evaluation and advice. When your eye stings or burns, it's sending a message. Try changing to a gentler eye-drop or gel, and see your ophthalmologist, who may recommend one of several procedures.
Punctal Plug Insertion is a simple procedure to partially block the tear duct, so that natural or artificial tears will remain on the eye longer. They cause little or no discomfort, and removal is often as simple as a saline pressure wash. Collagen plugs are an option for short term use. They are self-dissolving, and are effective for approximately 10 days.
Eyelid weights (available from MedDev Corp.)
Skin Tone External Eyelid Weights are the newest development, and work quite well. The weight on the eyelid works with gravity to assist blinking. It's worn on the upper eyelid, just above the eyelashes, and is attached daily with a double-sided adhesive strip. They're available only with a prescription. Potential downsides are irritation caused by the adhesive, and problems with the adhesive lasting during long days. For Bell's palsy patients, where paralysis is temporary, it can be an excellent short-term solution. For patients with permanent paralysis it's useful for calculation of the weight to be permanently implanted, and helps the patient adjust to living with an eye weight prior to implantation.
Gold Eyelid Weights are also used to help eyelid closure. They work on the same gravity-assist principle, but are sewn into the eyelid. (Shown here on the eyelid surface. When sewn into the eyelid it's visually undetectable.) The smaller weights are not uncomfortable for most people. The weight is removed as soon as enough function returns to the eyelid. In cases of permanent facial paralysis it can be left in place indefinitely. It is, however, a surgical procedure, and should be done only after careful consideration. As with any surgery, infection can occur, and swelling can last for several weeks. The eyelid and crease area can appear distorted, and vision can be affected. The weight, particularly if above 1.2 grams can cause the eyelid to droop. In spite of the cautions noted, it is well tolerated by most patients, and provides good protection for the cornea, as well as an improved appearance. Spring insertion is another, less frequently used type of surgical implantation.
Because we sleep in a horizontal position eye weights do not help keep the eye closed while sleeping. The effects of gravity are key to the success of eyelid weights, so its possible that even with an eyelid weight, additional protection may be needed while sleeping.
Lower lid elevations and surgical tightening of the lower lid can help prevent moisture from accumulating between the eye and a droopy bottom lid instead of spreading over the cornea.
Tarsorrhaphy is a procedure to sew a portion of the upper and lower lids together. When possible, only 5mm at the outer corner of the lids (lateral tarsorrhaphy) are stitched to maintain good vision, comfort and best possible appearance. If limited to 5mm or less, the appearance is not as bad as its description sounds. The eyelashes are undisturbed, and make-up can be worn. However, the procedure is not always effective unless a larger area is stitched, and a larger area may interfere with peripheral vision, and become more noticeable. If a medial tarsorrhaphy is suggested (rare even for permanent FP; shouldn't be needed for BP), it might be wise to seek a second opinion. This procedure is done over the center of the lids. It is disfiguring and functionally disruptive - a procedure of last resort.
Contact lenses are hydrophilic (hold water). They can provide a source of moisture directly over the cornea, and help protect the eye from injury due to debris. The eyelids help to hold a contact lens in place. If the lids become limp, contacts cannot be worn until function begins to return. Important notes of caution: Wearing the lens helps, but it is not a complete replacement for your tears - use plenty of saline or eye drops designed for use with contacts. At the acute stage, the eye can be so dry that it is impossible to keep a contact lens moist for more than a few minutes at a time. In this situation, contacts can not be worn.
**DO NOT LET THE LENS DRY OUT! A dry contact directly over the cornea is dangerous. This is very important - IF YOU CANNOT KEEP THE LENS MOIST, DO NOT WEAR IT! **