Plug designs vary to fit the punctum

Patient comfort and a tight hold are the major concerns in choosing a permanent punctum plug.

There is general agreement in ophthalmology that punctal plugs are indicated when first line treatment with artificial tears does not improve a patient’s dry eye symptoms.

But punctal plug designs vary from manufacturer to manufacturer. Some models work better in the hands of one practitioner than another. One design features a collapsible portion that allows easier insertion. Another fits into the canaliculus instead of the punctum. Several have flattened heads to minimize foreign body sensation. A model that is now in clinical trials will use a thermoplastic material to conform to the patient’s punctum.

For this article, Ocular Surgery News asked a range of experts in dry eye management, “What is your punctal plug of choice?” Their answers show a wide range of opinions and preferences.

Sharpoint UltraPlug

Stephen Lane, MD, a clinical professor of ophthalmology in the department of ophthalmology at the University of Minnesota, told OSN he has used several brands of punctal plugs; however, he prefers Surgical Specialties’ Sharpoint UltraPlug.

“One of the things I like the most is that the inserter has a very fine tip to dilate the punctum. As a result, you can open the punctum very easily to insert the plug,” Dr. Lane said.

Fit and comfort are important factors in the choice of a punctum plug.

Dr. Lane said although most punctal plugs are similar in using silicone as the plug material, “the stiffness of the material is a little bit different.”

He said the cone-shaped end of the UltraPlug is relatively firm, “so as you are trying to get it through a space that is a little smaller in terms of the diameter of the punctum, it’s got a little bit of stiffness, which helps to get it into the orifice.”

The head, which sits on the outside of the opening, on the surface of the lid, is also smooth and conforms nicely to the opening, Dr. Lane said. “So there’s not a lot of extrusion that might rub on the conjunctiva and cause irritation.”

“When improperly sized, the plugs do fall out occasionally,” Dr. Lane said.

“I would say less than 5% of the time in my usage. I tend to try to oversize them a little bit so they don’t fall out. I also tend to oversize them so you can’t insert them too deeply and lose them in the punctum itself,” he said.

“I think it’s not a problem if you put a plug in and it falls out; the patient becomes symptomatic, they come back and you place another plug. There is the potential, however, if you lose one in the canaliculus while placing it, that it could cause potential stagnation and can be difficult to remove. So I tend to oversize them a little bit,” he said.

When a patient has slight discomfort, Dr. Lane said he checks the plug’s position.

“It may be fitting too loose; it may be moving around. Sometime it may be sticking up a little bit and irritating the conjunctiva. So you can try and do some manipulations of the plug itself to try to get it into a better position. Sometimes a different size is necessary,” he said.

Dr. Lane said he rarely has problems removing the plugs.

“It’s very easy to slip underneath them with small forceps and pull them out. The difficulty is if it gets lost in the punctum or in the canaliculus. Those can be quite difficult,” he said.

According to Dr. Lane, improved inserters and the availability of multiple plug sizes allowing for a more customized fit have been the best improvements in plug technology.

Tear Saver

Christopher Rapuano, MD, a cornea specialist at Wills Eye Hospital in Philadelphia, told OSN his current favorite punctal plug is the Tear Saver by CIBA Vision.

“I like the sizes they have. I like the packaging and the exact shape of the plug. They tend to go in reasonably easily and have a low-profile head — the top of the plug. The price is also reasonable,” Dr. Rapuano said.

Dr. Rapuano said he likes the shape of the head of the Tear Saver.

“It seems to have a nice arrow-shaped fit that stays in pretty well. The top part is nice and flat. I used to tell patients that 10% of the time I had to take the plug out because they would feel it. Now it’s much lower than that — less than 2%.

“The older plugs used to have a sort of dome-shaped head that often poked at the conjunctiva or poked at the eye a little bit. Patients would feel it. The patients hardly ever feel a very flat head,” he said.

The low profile head has been the best improvement in plug design, he said.

The most common problem he had in using the Tear Saver is that the plugs sometimes fall out, he said. He has not had any problems with infection or dacryocystitis.

“We have had problems with [plugs falling out], but I’m not convinced one plug is any different from another. I try to put in the biggest plugs that I can fit. If one plug falls out, I’ll put in a bigger plug in next time,” Dr. Rapuano said.

According to Dr. Rapuano, surgeons must be careful not to snap the head off a plug when removing it, especially when using larger plugs.

“You have to remember to grab the shaft and not the head when you pull it out,” he said.

FlexPlug

Sylvia Norton, MD, a corneal surgeon in practice in Syracuse, N.Y., prefers the FlexPlug made by Eagle Vision because of the comfort the plugs provide in the larger sizes.

“There are some other companies that make larger plugs, but they are uncomfortable. The top of the plug can be irritating in some brands,” Dr. Norton said.

Dr. Norton said other plugs can also move around and change orientation as a result of patients rubbing their eyes.

She is seeing an increasing number of patients who need 0.7-mm and larger plugs, up to 1.1 mm, she said.

“It’s important to understand that the larger the hole, the more it may contribute to excessive outflow disorder, which can be a cause of dry eye syndrome,” she said.

“Most of us just think of the production. It’s sort of the same mechanism as one has to think about glaucoma, that’s there’s an equilibrium balance between the amount of fluid being made and the amount of fluid being taken away.

“I think it varies somewhat with age of patients and with climate. I think when you have a place where there’s a lot of allergic responses, like in our area, people who rub their eyelids tend to stretch their skin and stretch the punctum. So they tend to have larger openings also,” she said.

Dr. Norton said the ideal situation would be a soft, cement-like substance a surgeon could “pour” into the puncta that would perfectly conform to each person’s punctum.

“I think overall that’s why it’s important to have different sizes. Certainly no one size will fit all, that’s for sure. That’s not the way punctal holes are made,” Dr. Norton said.

Parasol

Paul Mitchell, MD, prefers to use the Parasol Punctal Occluder produced by Odyssey Medical Inc.

“It’s replaced all the others I’ve used in the past,” Dr. Mitchell told OSN. “It goes in easily and it stays in.”

He said the Parasol is shaped like a “half-open umbrella.”

“As you put it through the punctum, it collapses. So it goes in easily,” he said. “Then once it’s past the punctal ring, it expands and resists coming back out,” he said.

Dr. Mitchell said he has not had problems removing the Parasol.

“It will come. The difference is, for the amount of effort it takes to come out it goes in very easily,” he said.

“If you compare it to a standard, rigid cone plug, the difference is the amount of force and effort needed to place it vs. the amount to remove it. All rigid ones, to get a plug that will stay in, you really have to work at getting the biggest plug you can possibly get into the punctum. That takes a bit of effort. You have stretching, dilating. Any standard plug that goes in easily is also going to come out easily,” Dr. Mitchell said.

Although the Parasol is offered in a large version, he said he uses the small and medium versions for most of his patients.

“There is the rare person with a very large punctum that actually needs a large plug,” he said.

Dr. Mitchell said he has not seen problems with dacryocystitis or infection. However, he said, canaliculitis can occur.

“You’ll get an infection trapped downstream from the plug if there’s a more distant downstream obstruction. You get a little pocket of tears trapped between the plug and the more distant infection,” he said. “You can see that with any plug and it is easily treated.”

Dr. Mitchell said he thinks Parasol has been the best improvement in plug design.

“With a standard plug, you always go with the largest one you can place so it will stay in. For the Parasol, I’ve changed. I use the smallest one that will stay in,” he said.

“[The Parasol] has a slightly looser fit. It’s more comfortable. You’re less likely to get rubbing from the cap and less likely to get irritation from the plug. Now rather than the biggest one you can get to stay in, you can go with the smallest,” he said.

Dr. Mitchell said irritation caused by the cap rubbing against the conjunctiva is the biggest problem he has seen with all punctal plugs.

“The only one that wouldn’t would be a canalicular plug. But the problem with canalicular plugs is that once you place them you don’t know where they are anymore; you don’t know if they are still there. You don’t know if you can place a second one because you never want to put two different plugs in the canaliculus; you can trap tears and get an infection,” he said.

The Herrick

By contrast, Alan Gordon, MD, a general ophthalmologist in private practice in Lewistown, Pa., told OSN he uses the Herrick Intracanalicular lacrimal plug (Lacrimedics) most often.

“I’ve had patients feel some of the other plugs that are placed at the surface. Patients don’t feel the Herrick plugs,” he said.

Dr. Gordon said the plugs can be irrigated out if it is necessary to remove them.

“[It is] probably not as easy to take out as other plugs. But, the main thing is that there is no foreign body sensation and easy insertion,” he said.

Dr. Gordon said he does occasionally have problems with the plugs.

“One of the disadvantages of intracanalicular plugs is that you can’t always be sure it’s in. Sometimes that question comes up. The patient will have more symptoms and you’ll say to yourself ‘I wonder if the plug is in’ because it’s possible it came out. But the plug usually does not come out,” he said.

Dr. Gordon said if there is a question about whether the plug is still in place, transillumination can be done to visualize the plug. If there is still a question, a temporary plug can be put on top of it, and the patient can be checked in 5 days.

Transillumination is easy because of a titanium-based dye in the plug. Lacrimedics also has a 4-mm and 6-mm positioning tool to make sure the plug is inserted past the ampule, which is known to have nerve endings that can be irritated by a foreign object.

“I’ve also had some patients who have experienced granuloma formation if the edge of the plug is not all the way in the canaliculus, which is easy to manage with a steroid. You also have to reposition the plug. It’s just like any other plug,” he said.

“I’ve had some patients come in and complain of excessive tearing. That’s probably the most common thing, and it happens in all plugs,” he said.

SmartPlug

Samuel Masket, MD, an anterior segment surgeon in private practice in Los Angeles and clinical professor of ophthalmology at the Jules Stein Eye Institute, discussed the Medennium SmartPlug with OSN.

According to Dr. Masket, the SmartPlug is currently still under investigation for Food and Drug Administration approval. The trials are closed, and the device is proceeding through the investigational process, “hopefully pending approval in the not-too-distant future,” he said. The data are currently being accumulated and analyzed.

Dr. Masket is one of the surgeons who implanted the SmartPlug during clinical trials. He said the SmartPlug differs from other punctal plugs “in every way imaginable.”

The SmartPlug is made of a thermal plastic acrylic that behaves differently at body temperature than at room temperature.

“At room temperature it is a solid, long, thin rod that is placed in vertical portion of the canaliculus. Body temperature alters the shape of the thermoplastic and it contracts to form a small pellet that conforms to the size of the vertical canaliculus and occludes it as it expands in its diameter,” Dr. Masket explained.

The plug differs from other plugs in that it does not have a projectile or mushroom-shaped cap. “There is nothing to sit on the surface and irritate the conjunctiva,” Dr. Masket said.

According to Dr. Masket, removing the plug by irrigating it through the canaliculus into the nasolacrimal duct is not difficult; however, removal is not certain because it cannot be visualized.

“Also, it is not radio opaque. So even with an X-ray one can’t see it in the canaliculus,” Dr. Masket said. “But given its ability to expand and fill the vertical canaliculus, I doubt it would migrate.”

Dr. Masket said he has not seen any infections while using the plug, nor was he made aware of any infection during the trial.

For Your Information:

• Stephen Lane, MD, can be reached at 280 N. Smith Ave., Suite 840, St. Paul, MN 55102; (651) 222-5666; fax: (651) 227-9370. Dr. Lane does not have a financial interest in any of the products mentioned in this article, nor is he a paid consultant for any company mentioned.
• Christopher Rapuano, MD, can be reached at Wills Eye Hospital, 900 Walnut St., Philadelphia, PA 19107; (215) 928-3180; fax: (215) 928-3854; e-mail: cjrapuano@hslc.org. Dr. Rapuano has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
• Sylvia Norton, MD, can be reached at the Jerva Eye Laser Center, 475 Irving Ave., Suite 110, Syracuse, NY 13210; (315) 476-2129; fax: (315) 472-6501. Dr. Norton has no direct financial interest in the products mentioned in this article. She is a paid consultant for Eagle Vision.
• Paul Mitchell, MD, can be reached at 895 Canton Road, Marietta, GA 30060-7275; (770) 427-8111; fax: (770) 427-6913. Ocular Surgery News could not confirm whether or not Dr. Mitchell has financial interest in any of the products mentioned in this article, or if he is a paid consultant for any company mentioned.
• Alan Gordon, MD, can be reached at 27 Sandy Lane, Suite 220, Lewistown, PA 17044; (717) 242-2514; fax: (717) 242-3188. Dr. Gordon has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
• Samuel Masket, MD, can be reached at Advanced Vision Care, 2080 Century Park East, Suite 911, Century City, CA 90067; (310) 229-1220, fax: (310) 229-1222; e-mail: avcweb@aol.com. Ocular Surgery News could not confirm whether or not Dr. Masket has financial interest in any of the products mentioned in this article, or if he is a paid consultant for any company mentioned.

• Surgical Specialties, manufacturer of the Sharpoint UltraPlug, can be reached at 100 Dennis Drive, Reading, PA 19606; (610) 404-1000 or (800) 523-3332; fax: (610) 404-4010.
• CIBA Vision, manufacturer of the Tear Saver punctal plug, can be reached at 11460 Johns Creek Parkway, Duluth, GA 30097; (678) 415-3711; fax: (678) 415-2320.
• Eagle Vision, manufacturer of the FlexPlug, can be reachsed at 8500 Wolf Lake Drive, Suite 110, P.O. Box 34877, Memphis, TN 38184; (901) 380-7000; fax: (901) 380-7001; e-mail: info@eaglevis.com.
• Odyssey Medical, manufacturer of the Parasol Punctal Plug, can be reached at 5828 Shelby Oaks Drive, Suite 21, Memphis, TN 38134; (901) 383-7777; fax: (901) 382-2712; e-mail: info@odysseymed.com.
• Lacrimedics, manufacturer of the Herrick Lacrimal Plug, can be reached at 310 Prune Alley, P.O. Box 1209, Eastsound, WA 98245; (800) 367-8327 and (360) 376-7095; fax: (360) 376-7085; e-mail: info@lacrimedics.com.
• Medennium, manufacturer of the SmartPlug, can be reached at 15350 Barranca Parkway, Irvine, CA 92618; (949) 789-9000; fax: (949) 789-9035; e-mail: info@medennium.com; Web site: www.medennium.com.