New shape for the punctal plug better fits into the punctum

Image credit: Robert Latkany, MD/Oasis Medical

Silicone punctal plugs have been the decades-long mainstay for physicians treating patients with dry eye. The plugs do their job, preventing loss of tears, but are associated with a few complications.

Robert Latkany, MD, who is in private practice in New York, United States, devised a new and improved punctal plug, the Soft Plug Extended Duration 180 (Oasis Medical) that may circumvent the issues associated with both silicone plugs and other existing temporary plugs. Silicone plugs can often fall out as early as the next follow-up visit, patients frequently complain of a foreign body sensation, and silicone plugs can result in the formation of a pyogenic granuloma in the punctum. Temporary plugs are sometimes difficult to insert and are often undersized.

Evolving plug technology

Over the course of his career, Latkany has relied heavily on punctal plugs to treat patients with pure aqueous deficiency with or without meibomian gland dysfunction. He recounted that about 2 decades ago, he transitioned from using silicone plugs with their inherent problems to those that were made of an absorbent synthetic material intended to be temporary with the potential to remain in place for up to 180 days. He no longer has to deal with plugs falling out, pyogenic granulomas or complaints of a foreign body sensation. Patient acceptance was also higher.

Although this technology seems like an almost perfect solution, the currently available plug sizes range only from 0.2 to 0.5 mm in diameter. In Latkany’s experience, most of the plugs he inserts are at the larger end of the spectrum because most patients have larger punctal openings. “The patient will receive the most benefit from a larger diameter plug. The wider the plug, the more tears are retained and the greater the symptom relief,” he commented.

An issue that led him to design a new device is that the currently available plugs are cylindrical on both sides with no tapering of the tip. “The clinician is therefore inserting a rounded cylindrical object into an oval or linear punctal opening, which can result in some resistance to insertion because of the differences in shapes,” he explained.

In addition to the shape, he also wanted a plug that is wider than 0.5 mm to become available.

Ultimately, his ideas resulted in the creation of a plug that is nearly one-size-fits-all. It is tapered at one end and slightly larger at 0.6 mm in diameter. “This would be easier to insert because of the tapered edge and able to fit into a smaller opening,” he said.

The tapered tip end is 0.25 mm wide and the bulk of the plug is 0.6 mm wide. “This results in tear blockage in the canaliculus with a larger plug as well as the ability to insert the plug into most punctal openings,” he said.

Latkany reported that he now can insert these larger temporary plugs in 95% of his patients. While it may still be possible to insert these tapered plugs into the less common 0.2- or 0.3-sized openings, punctal dilation with a punctal dilator may be necessary beforehand. There is a small learning curve associated with inserting these tapered plugs.

“Because of the tapered edge the plugs are inserted deeper into the styrofoam package inserts, so grabbing them with forceps while using a slit-lamp may be necessary. In addition, in very large punctal openings, they may immediately pop back out after insertion. To correct this, I advise gently pulling on the lid to tighten the punctal opening just before inserting the plug then quickly tap the plug further into the ampulla,” he said. More tears are occluded using the larger plug.

This Soft Plug Extended Duration 180-T tapered temporary plug is made of polydioxanone, an absorbable synthetic material. The plugs are supplied sterile, two plugs per package, so that a plug can be placed into each canaliculus, according to the manufacturer.

“The beauty of the design is that it will fit into most openings and clinicians don’t have to spend time determining which size may be optimal for individual patients,” he said. The Soft Plug Extended Duration 180-T plug was approved for use in the US in 2022; international approval is pending.