Clinicians consider patient's tolerance, anatomy, physiology before punctal occlusion

Issue: May 1998

Consider anatomy, physiology

Leo P. Semes, OD: My philosophy for reversible lacrimal occlusion (RLO) rests on a basis of anatomy and physiology as well as a good patient history. For starters, about 75% of tears are lost to evaporation, so RLO will supplement tear volume. That amount of additional tear volume, however, may be important - even critical - in certain situations.

Patients with ocular surface abnormalities not related to blepharitis are my primary candidates for RLO. Contact lens wearers whose symptoms may include reduced wearing time or persistent irritation are also candidates. A small subset of patients who may benefit from RLO are those whose environmental or occupational settings temporarily compromise an already borderline dry eye condition.

Clinical findings that lead me to recommend RLO include premature tear break-up or decreased contact lens tolerance. With significant clinical findings such as surface staining, remediation with lubricating ointments or tear supplements comes first. Then, I use a dissolvable collagen implant in the inferior punctum, sometimes only on one side, for a 1-week trial.

When the patient returns for re-evaluation, I question whether and for how long any improvement had been observed. If the patient says that relief was week long, I question the efficacy. When the patient reports that the first few days were fine but that the effect dissipated, then RLO with a plug or implant has a better prognosis.

My choices for RLO include plugs (that remain visible in the punctum) and intracanalicular implants that reside in the canaliculus. My first choice, despite some recent reports of adverse reactions, is intracanalicular implantation. My experience has been that older patients with stenotic puncta have difficulty retaining a plug.

I re-evaluate in 2 weeks, looking for relief of symptoms. I do not perform laser or thermal punctoplasty. The advantage of RLO is that punctal plugs can be removed easily with forceps, and intracanalicular implants can be irrigated from the canaliculus.

For Your Information:

Leo P. Semes, OD, is a member of the Editorial Advisory Board of Primary Care Optometry News He can be reached at the University of Alabama, 908 S. 19th St., Birmingham, AL 35205; (205) 934-6773; fax: (205) 934-6758; e-mail: LSemes@icare.opt.uab.edu. Dr. Semes has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.

Use collagen plugs first

Cristina M. Schnider, OD, MSc, FAAO: I recommend punctal occlusion when I can document an aqueous deficient dry eye or in a dedicated soft lens wearer whose lenses continually drain the lacrimal lake.

I rely on tear volume tests such as Schirmer's or Zone Quick (phenol red thread test distributed by Menicon) for confirming true lacrimal insufficiency in non-soft lens wearers. However, because soft lenses act like sponges on the eye, particularly in dry environments, even a person with a normal tear volume can suffer when wearing hydrogels.

I generally test the effect using collagen plugs first. I prefer to have results confirmed on at least two occasions before recommending more permanent occlusion. If collagen plugs do not improve symptoms, I may confirm with silicone plugs, because false negatives are common with collagen due to incomplete occlusions.

Once I am convinced that occlusion will help with symptoms and/or signs, I prefer cautery as a method. It is relatively quick, inexpensive and usually effective.

For Your Information:

Cristina M. Schnider, OD, MSc, FAAO, is the director of marketing and professional relations for Menicon USA Inc. She can be reached at 333 Pontiac Way, Clovis, CA 93612-5612; (209) 292-2020, ext. 114; fax: (209) 292-2021; e-mail: od@menicon.com.

Sensitive to subtle symptoms

Albert M. Morier, OD: Patients who suffer from symptoms of dry eye are much more common than we know. Many people fail to mention it because they either don't recognize it or believe it is simply a condition that can't be resolved except for the temporary relief of rewetting drops.

I am sensitive to the subtle - and not so subtle - symptoms that are elicited in the case history. I use a questionnaire that attempts to identify the dry eye patient. I use a Schirmer's strip and a phenol red thread to try to quantify the dry eye state. Because these tests have high false-negative results, I trust the one that demonstrates dry eye the best.

I use fluorescein staining to look for punctate keratitis and tear break-up time. If the patient's symptoms are significant enough, I present the option of a diagnostic collagen implant trial. After explaining the noninvasive nature of the procedure, the patient is very comfortable with it and looks forward to possible relief. This is especially true of the contact lens wearers. I will implant two or three collagen implants in each inferior puncta to ensure a true test.

I use 0.3-mm collagen plugs most often. I will use an Oasis plug with rounded ends as the first implant, followed by an Eagle/Ciba type implant. I find they prevent the implant from working its way back out of the puncta, as their ends flare out.

I see the patient in 2 weeks, and if this is beneficial, we use the silicone plugs. I stay away from the term "permanent" plug, because it sounds final.

My decision about which modality to use is quite easy. Cautery requires an injection of lidocaine into the lid, which stings, especially when injected near the puncta. The procedure is very inexpensive and works well and permanently. Reversing the procedure is very intricate. I do not care for cautery, because the idea of burning the lid tissue does not appeal to most of my patients. Laser punctoplasty requires only topical anesthesia and is seldom painful. It often requires multiple sessions, especially in younger people, to create an effective punctal block.

Silicone punctal plugs are easily reversible, require no anesthetic and are easy to implant. Patients accept these very readily. If they fall out, I replace them. If they fall out a second time, I refer for laser punctoplasty. This does not happen very often.

For Your Information:

Albert M. Morier, OD, is an instructor in clinical ophthalmology at Albany Medical College, Albany, NY. He can be reached at (518) 355-0956; fax: (518) 355-1208; e-mail: amorier1@nycap.rr.com. Dr. Morier has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any company mentioned.

Consider patient's tolerance

David R. Hardten, MD, FACS: Many patients that complain of irritation of their eyes have dry eye. The diagnosis and management of this can often be quite complex. It is important to properly diagnose ocular surface problems. Aqueous deficiency dry eye means the patient does not produce enough tears. Blepharitis can lead to poor tear quality with poor wettability of the surface and is important to diagnose and treat appropriately. Of course, one option for aqueous deficient patients is to increase the amount of external lubricants applied. Punctal occlusion is also a very effective modality of improving symptoms by retaining tears or lubricants that are instilled by the patient.

One of the key issues in trying to decide whether punctal occlusion will be tolerated is to make certain that the patient will not have excessive tearing or epiphora after the punctal occlusion. Therefore, it is helpful to get some assessment of the patient's tear production. For this, I basically divide my patients into three age groups:

20- to 40-year-olds - In this age group, it is extremely important to make certain that you do not excessively occlude the patient as these patients are at highest risk of having epiphora.
40- to 60-year-olds - In this group, there is still some risk of epiphora, but the risk is not as great as in the younger groups.
60+ years - In this group, the risk of epiphora is fairly minimal assuming the diagnosis of dry eye is correct.

In the typical patient presenting with dry eye, my first response is to try them on artificial lubricants. Once the patient is using artificial tear lubricants more than four times a day with improvement in symptoms, then I consider punctal occlusion.

A Schirmer's test with anesthetic is helpful to assess basal tear secretion. In the patient older than 60 with less than 10 mm of wetting after anesthetic, punctal occlusion can probably be safely carried out. In the patient with more than 10 mm of wetting, it is important to first try a temporary method of occlusion, especially in the younger patient. Silicone or collagen plugs are useful in these situations.

I place a collagen plug in both the upper and lower puncta and see the patient back 3 or 4 weeks later. This time frame is often too short for them to truly notice a benefit from the punctal occlusion, yet if the patient does not have epiphora, then it is safe to proceed with a more permanent form of punctal occlusion.

The easiest and most permanent way to occlude the puncta is with cautery. Unfortunately, though, this requires an injection into the area of the puncta and is a surgical procedure. Therefore, in many patients, punctal plug placement is preferred. Punctal plug placement is typically more difficult to perform, however, because of the fact that the plug is, by necessity, larger than the puncta. This requires stretching the puncta to allow insertion of a properly sized punctal plug.

In patients with Schirmer's testing of more than 10 mm, placement of an inferior punctal plug is appropriate to consider. The nice thing about punctal plugs is the fact that if the patient does have epiphora, the plugs can typically be removed. I would utilize the plugs that are truly punctal and not the canalicular plugs, as the canalicular plugs can become obstructed in the lacrimal system.

In the patient with Schirmer's tear testing of less than 10 mm of wetting who requires artificial tear lubrication at least every 2 hours, I think it is appropriate to proceed directly to permanent lower punctal occlusion at all age ranges. In these patients, I would consider placing a silicone punctal plug in the inferior puncta or using cautery punctal occlusion to occlude the lower puncta.

In patients with less than 2 mm of wetting on the anesthetized Schirmer's tear test I proceed directly to cautery punctal occlusion of the upper puncta and punctal plug placement in the lower puncta.

Argon laser punctal occlusion might be used for the very young patient, if it is difficult to place a punctal plug and there is concern that epiphora may result based upon the collagen plug test. This is still uncomfortable for many patients; therefore, to occlude the puncta successfully with the argon laser it is typically necessary to inject lidocaine anesthesia. However, the use of laser punctal occlusion in my practice is extremely limited.

The main issues to consider in dry eye patients are:

The potential for epiphora as diagnosed by the collagen plug test, by Schirmer's tear testing or by the frequency of drops required to control symptoms.
The patient's tolerance of
1. Punctal plugs: minimal pain but difficult to insert in many.
2. Cautery punctal occlusion: high success rate.
3. Laser punctal occlusion: high failure rate yet increased ability to reverse, if necessary.

For Your Information:

David R. Hardten, MD, FACS is a consultant in corneal and refractive surgery. He can be reached at Lindstrom, Samuelson and Hardten, Park Avenue Medical Office Building, Ste. 106, 710 E. 24th St., Minneapolis, MN 55404-3810; (612) 336-5493; fax: (612) 336-5606. Dr. Hardten has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any company mentioned.