Punctal Occlusion

BY PETER W. SHENON, M.D.
APR. 1997

Keratoconjunctivitis sicca (KCS) is a major reason patients stop wearing contact lenses. Inferior punctal occlusion is a safe and effective treatment for KCS as well as ocular surface disease (OSD), reflex tearing and other conditions caused by dry eyes.

Many patients with dry eyes who have stopped wearing contact lenses may now be considering keratorefractive surgery. Punctal occlusion can help some of these patients avoid surgery and return to contact lenses. Even patients who do opt for corneal surgery will benefit from the improved tear film after punctal occlusion. In addition, punctal occlusion before radial keratotomy may help prevent the overcorrection that many KCS-sufferers experience after RK surgery.

WHO WILL BENEFIT FROM PUNCTAL OCCLUSION?

Young patients who still produce some tears respond well to punctal occlusion. Older patients also benefit, but the response may not be as dramatic because their eyes are drier. Some patients, particularly elderly individuals with very dry eyes, see better after punctal occlusion because the procedure improves the tear film. Even patients with very dry eyes derive some benefit from punctal occlusion because artificial tears will remain in their eyes longer after the procedure.

Patients with pterygia usually have KCS and OSD and are excellent candidates for punctal occlusion. Patients with itchy eyes, red or irritated eyes, or recurrent conjunctivitis will also do well because KCS is often the underlying cause of these signs and symptoms. Intermittent tearing, which is usually caused by reflex tearing from the irritation of chronic dryness, can often be relieved by punctal occlusion.

EFFECTIVE & SAFE

Of 540 of my patients who had inferior punctal occlusion, 84 percent said their eyes felt better and they needed to use artificial tears less often after the procedure. Four percent felt so much better they no longer needed artificial tears. Twelve percent noticed no improvement, but these were usually patients with very dry eyes who needed superior punctoplasty as well.

Inferior punctal occlusion is safe for all ages. The superior canaliculus alone can carry away more tears than it might normally have to carry when both canaliculi are open. Tear production in a 65-year-old individual is about 40 percent of tear production in a 21-year-old, so older patients no longer need all four drainage ducts. Punctal occlusion is safe for women who develop dry eye symptoms while taking oral contraceptives. The procedure is even safe for teen-agers with dry eyes. I have done it on patients as young as 12.

I usually start by closing the inferior puncta. However, if a patient's superior puncta are very small or not in a normal position, I close the upper puncta first.

When discussing punctal occlusion with patients, be sure to explain that:

• tear glands produce tears, and drainage ducts carry tears away. (Use the phrase "drainage duct," not "tear duct.");
• tears wash across the eye and drain away through the drainage ducts;
• there are upper and lower drainage ducts on each side of the eye;
• dry eye symptoms indicate that tear production is significantly reduced. Since we cannot increase tear production, we will block the drainage ducts to prevent the tears from draining away too quickly;
• closing the drainage ducts will not interfere with the tear production (a common misconception among patients);
• punctal occlusion can be compared to putting a plug in a sink;
• after closing the lower drainage ducts, the upper drainage ducts will carry away excess tears;
• the procedure will make their eyes feel better the rest of their lives;
• punctal occlusion is a safe, quick, widely performed procedure;
• and most important, punctal occlusion is reversible.

INDICATIONS FOR PUNCTAL OCCLUSION

KCS -- We see KCS most often in women and older patients, although it's not uncommon in teen-agers.

Diagnosis is easy. Ask patients if their eyes feel hot, dry, gritty or sandy, or if they burn, smart, itch, water or tear. They may acknowledge only one of these symptoms, so ask about all nine. Itching eyes are often caused by KCS, not allergies, and watery eyes are usually caused by reflex tearing.

Additional clues to KCS are:

• intermittent or chronic redness;
• irritation in the inner corners of eyes;
• fluctuations in vision;
• contact lens intolerance;
• an intermittent "foreign body" sensation; and
• subconjunctival hemorrhages, which may be caused when patients rub their eyes to relieve the irritation of dryness.

Recurrent conjunctivitis is often seen in patients with KCS because a dry eye is more susceptible to infection, and KCS can cause pterygium, pinquecula and chronic injection.

Reflex Tearing -- Reflex tearing, a response to the irritation from chronic dryness, is usually intermittent and can be unilateral or bilateral. These watery tears are hypotonic and do not relieve dry eyes. (Be sure to ask patients if their eyes water outdoors in the wind or cold, conditions that irritate dry eyes.) Reflex tearing is a common problem in older individuals, and is more likely the cause of watery eyes than an obstruction in the lacrimal drainage system.

When explaining reflex tearing to patients, I refer to "good" tears that lubricate the eye, and "bad" or reflex tears that we produce when we cry or have a foreign body in our eye. I emphasize that reflex tears are too dilute to relieve dry eye symptoms, and that patients must use artificial tears frequently.

Punctal occlusion is an effective treatment for reflex tearing. Blocking the drainage ducts allows the natural tears to stay in the eye longer to relieve dryness. See "Educating Patients" for suggestions on how to explain the procedure.

Ocular Surface Disease -- OSD can be divided into primary and secondary cases, and it's important to understand the difference. Secondary OSD occurs when the corneal and conjunctival epithelium become secondarily irritated or damaged, usually due to lack of moisture and mucin in the tear layer. Less common causes of secondary OSD are irritation from preservatives in eye drops, blepharitis, conjunctivitis, acne rosacea, hormonal imbalance and contact lenses.

Primary OSD is less common and usually more severe than secondary OSD. It is characterized by a loss of goblet cells and keratinization of the conjunctival epithelium and is often associated with Sjögren's syndrome. Most patients with primary OSD demonstrate significant rose bengal staining and compromised tear quality and quantity.

External Eye Diseases -- KCS is associated with several external eye diseases. For example, I see many women with conjunctivitis, itchy eyes, red irritated eyes, or recurrent eye infections. Rose bengal stain demonstrates that the underlying problem is most often a dry eye (especially in patients who complain of recurrent conjunctivitis). Treat any infection, start artificial tears and consider punctal occlusion.

KCS, OSD and exposure to excessive amounts of ultraviolet light may cause pterygia. Punctal occlusion will make these eyes more comfortable and less injected. By reducing the inflammation, the pterygium will be less obvious and may not need to be removed. If it does need to be excised, it will be less likely to recur.

Corneal Ulcers and Contact Lenses -- I have seen about 35 cases of bacterial corneal ulcers in patients wearing extended wear soft contact lenses. All but one of these cases had moderate-to-severe rose bengal staining in both eyes. I believe that KCS is one of the major reasons these patients develop bacterial ulcers.

Ask every patient about dry eye symptoms and use rose bengal before prescribing extended wear soft contact lenses. If their eyes are dry, do punctal occlusion, and if they still have KCS symptoms or rose bengal staining after the procedure, then prescribe daily wear, low water content lenses. Avoid high water content lenses that require a more normal tear layer.

COLLAGEN IMPLANTS: A USEFUL TEST

Collagen implants provide a useful test to evaluate the potential effectiveness of permanent occlusion.

Always use implants in patients under age 25 and in patients over age 55 who complain of watering and tearing, or if there is severe OSD as demonstrated by rose bengal. Consider collagen implants for patients who are apprehensive about permanent occlusion, or to confirm that permanent occlusion is indicated.

Inserting collagen implants is simple. Although they are available in five widths, I usually use only the 0.4mm, 0.5mm and 0.6mm implants. Administer an anesthetic eye drop, place the patient in front of a slit lamp, and dilate the punctum with the tip of a jeweler's forceps. Hold the package of implants in the slit lamp beam and remove an implant with tying forceps. Insert the implant into the punctum at a 45-degree angle (down and nasal). Use jeweler's forceps to push the implant into the horizontal portion of the canaliculus until it's no longer visible in the punctum (pulling the lid laterally with your thumb or finger will straighten the canaliculus and make insertion easier). Insert two of the largest implants that will fit into each punctum. Evaluate implant patients in one week.

Caution: Do not perform this test if the patient has a cold, and be sure to treat any conjunctivitis before inserting implants.

I don't recommend the short collagen implants that are designed to go into the vertical portion of the canaliculus near the punctum. These plugs may not adequately block the canaliculus, and they may rub against the eye or extrude spontaneously.

After inserting collagen implants, it's important that patients understand the implications of the test. Tell patients:

• If the implants don't cause tearing, it's safe to do the permanent procedure.
• Your eyes may feel better for only two or three days. After the implants dissolve, your eyes will feel worse again.
• If your eyes don't feel better with the implants, but there was no tearing, you should have punctal occlusion anyway.
• Intense itching in the inner corners of your eyes and lids indicates an allergic reaction to the collagen. This does not contraindicate the permanent procedure.
• Continue to use preservative-free tears, even while the implants are in place, to prevent reflex tearing.

Although collagen implants can help predict the success of punctal occlusion, they have some disadvantages. Some patients become anxious and decide not to have permanent occlusion even though their eyes felt better with the implants. Implants may cause lid discomfort, and patients may worry that the permanent procedure will cause the same problem. Confused or elderly patients may not understand the purpose of the implants or even remember that they were inserted.

Also, you may find that some patients are not sure if the implants helped and you must repeat the test, while others don't notice any improvement and they assume that the permanent procedure won't help either. These patients' eyes are probably so dry that they will require both inferior and superior punctal occlusion.

CHOICES FOR PERMANENT OCCLUSION

There are four methods of permanent occlusion: Freeman silicone plugs and plugs of similar design, Herrick silicone plugs, cautery punctoplasty and laser punctoplasty.

Freeman-type plugs can be inserted without anesthesia and are easily removed, so you can use them as a primary procedure instead of collagen implants. These type plugs, however, can be difficult to insert, and they have been known to cause eye irritation and to extrude spontaneously. Also, patients can dislodge them by rubbing their eyes.

Herrick plugs are easy to insert, will not extrude spontaneously and do not require anesthesia. However, they can be difficult to remove, and they may become dislodged and block the common canaliculus or the nasolacrimal duct.

Cautery punctoplasty is inexpensive, takes one minute, and is very easy to do. Laser punctoplasty is expensive for both practitioner and patient and can make patients apprehensive. Also, laser punctoplasty may have to be repeated because the puncta may reopen spontaneously. Both laser and cautery punctoplasty require local anesthesia, and both procedures are reversible (although this is rarely necessary).

POSTOP CARE & INSTRUCTIONS

Patients should continue using preservative-free artificial tears after punctal occlusion. Hopefully, their eyes will feel better and they won't need to use the tears as often. Later, as their eyes feel better, they can try some of the less expensive tears that contain preservatives.

Conjunctivitis may occur immediately after punctal occlusion, but is easily treated with antibiotic drops. After the first week, however, conjunctivitis occurs less often in these patients because they now have a healthier tear layer and OSD is reduced.

Following laser or cautery punctoplasty, the puncta may become white and somewhat tender for a day or two, but this is never permanent.

A few of my patients have complained of a dry nose and throat after punctal occlusion, but this usually clears spontaneously in a week or two.

The most common cause of tearing after punctal occlusion is reflex tearing in eyes that are still dry. Invariably, rose bengal dye demonstrates conjunctival staining from continued dryness. Frequent use of preservative-free tears will correct this reflex tearing.

If intermittent tearing persists, prescribe FML or Flarex. Patients should use these steroid drops sparingly while continuing to use artificial tears frequently. Discontinue the steroids as soon as the tearing improves.

Occasionally, a patient has tearing but no rose bengal staining after inferior punctal occlusion. This may be due to a blockage in the superior or common canaliculus. Dilate the superior punctum and irrigate the canaliculus under local anesthesia to relieve the tearing.

You will rarely need to reverse inferior punctal occlusion, but if this is necessary, Freeman-style plugs are easily removed with forceps. Herrick plugs must be irrigated into the lacrimal sac down through the nasolacrimal duct. Gentle probing under local anesthesia will reverse laser and cautery punctoplasty.

SUPERIOR PUNCTAL OCCLUSION

If the eyes are still dry after inferior punctoplasty and they continue to stain with rose bengal (in spite of using artificial tears frequently), then consider superior punctal occlusion. Insert two of the largest collagen implants possible into each superior canaliculus. Patients should use artificial tears frequently to prevent reflex tearing, and return in one week. If the implants did not cause tearing, then block the upper puncta.

About 15 percent of patients experience constant tearing in one or both eyes after superior punctal occlusion. This is because the collagen implants did not completely block the tear flow. After permanent occlusion, the punctum is now completely closed and the eye may tear. Reverse the procedure as described above.

For older patients or patients with very dry eyes you may wish to forego implants and proceed with one of the permanent procedures. If there is constant tearing afterward, simply reverse the procedure. Although we may need to reverse about 25 percent of these patients, the relief this method provides to the other 75 percent makes it worthwhile.

If patients tear after superior punctal occlusion, use rose bengal to rule out reflex tearing. Patients who still have very dry eyes after all four puncta are blocked should use preservative-free artificial tears for relief. Some patients may need to use Flarex or FML to relieve occasional tearing. CLS

Dr. Shenon welcomes inquiries about punctal occlusion and rose bengal stain. You can reach him at (510) 935-5114.