Punctal Plugs for Dry Eye Before or After LASIK

In preparing the eye for LASIK, punctal plugs should be considered only as part of a larger strategy for addressing any dry eye before LASIK.

Before a patient undergoes either LASIK or PRK laser vision correction eye surgery, it is important for the surgeon to address any dry eye issues. This attention to dry eye before surgery is called “optimizing the ocular surface” and is critical to achieving the best possible outcomes after LASIK or PRK.

Too often, surgeons will simply place punctal plugs as a first and only strategy for addressing dry eye either before or after LASIK. It is important, however, to understand that punctal plugs should be viewed as one component of a larger overall strategy when preparing an eye for surgery and, in my experience, usually are not necessary.

When thinking about getting the eye ready for LASIK or PRK laser vision correction eye surgery, it is important to realize that there are two factors affecting tears and dry eye: 1) tear quantity (are there enough tears overall?) and 2) tear quality (regardless of the volume of tears, are the tears the correct composition so they can properly do their job?). Too often, surgeons and patients focus only on the first factor: tear quantity. There is a tendency to think of dry eye too simplistically: are there enough tears or not? It turns out the issue is much more complex. Most often, dry eye is caused by the tears not properly doing their job due to a tear quality problem that is independent of whether or not there are enough tears.

In my experience, it is much more important to first address tear quality as there typically is more room for improvement in this regard. Only after tear quality has been addressed and the eyes still are dry should attention be turned to punctal plugs, which effectively increase tear volume.

The tears are made of three layers. The bottom or “mucin” layer, adheres to the cornea and the surface of the eye and is made of proteins. It is produced by cells called goblet cells located in the conjunctiva. The middle layer, known as aqueous layer, is composed mostly of water and is made by the lacrimal gland. The top layer is called the “lipid layer” and is made of oils.

Each layer of the tears must be of the proper composition to function properly. If even one layer is abnormal in its composition, then the tears have poor quality and cannot coat and moisten the surface of the eye as well, regardless of how much tear volume there is. A problem with one or more of the layers of the tears is called a qualitative tear problem.

Therapies to treat qualitative tear problems are directed to the specific quality problem. For example, many people, due to a combination of diet and genetics, have a deficient lipid layer. The job of the lipid layer is to prevent evaporation. Patients with a quality problem in their lipid layer may have enough tears, but the tears do not properly stay on the eye during period of heavy use with decreased blinking, such as prolonged computer use. Other patients, particularly post-menopausal women, have chronic inflammation of the surface of their eyes which reduces the quality of all three layers of their tears.

Punctal plugs purely address tear quantity and not tear quality. It turns out that there are two “drains” by which tears leave the surface of the eye — an upper and a lower drain. Each drain is called a “punctum” and is located at the margin of the upper and lower eyelids towards the nose. Approximately 2/3 of the tears leave via the lower punctum while 1/3 leaves via the upper punctum of each eye.

Putting plugs into the puncta essentially plugs the drain so tears cannot exit. Plugs can be placed either on a temporary or a permanent basis. Often dissolvable plugs are used as temporary plugs and can last from a day to a couple of months, depending on the type of plugs used. Because the drain system is either partially (just lower plugs) or completely (upper and lower plugs) blocked, the tears essentially back up onto the eye and increase tear volume. Remember, though, plugs do not change the composition of the tears. If a patient has poor quality tears, the plug simply backs up more poor quality tears on the eye.

If someone has a tear quality problem, it is very important to first address that before plugs are place. Otherwise, plugs might be of little help or may actually make things worse. For example, if a post-menopausal woman has dry eye, the root cause may be inflammatory. Placing punctal plugs might just end up putting more inflammatory chemicals that are in the tears against the surface of the eye. The correct approach is to try to get tear quality as good as possible first. Only then, if necessary, should plugs be considered. In may practice, plugs always come after a thorough treatment directed toward tear quality.

There are several steps that can be taken to improve tears quality. Restasis is an FDA approved prescription medicine that essentially is an anti-inflammatory drop and helps the body make better quality tears by reducing surface inflammation (it also improves tear quantity for the same reason). Azasite is a drop that, on an off-label basis, can be used to directly treat lipid layer problems of the tears. Oral omega-3 nutritional supplementation also can improve tear quality. Other treatments that can improve tear quality include hot compresses on the eyelids and even oral doxicycline, tetracycline, or minocycline. Even light based skin treatments which treat acne rosacea can help improve tear quality.

If a patient’s eye still is dry despite these treatments, then it often is useful to add punctal plugs to the strategic approach. While I am in no way opposed to punctal plugs (they often are quite helpful) I just do not think they should be the first line of approach.

In general, though, getting the eye ready for LASIK is a critical part of the surgery. Each patient needs to be approached individually and for some, but not for most, punctal plugs are a helpful addition to the treatment strategy in my experience.

Punctal Plugs for Dry Eye Before or After LASIK

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