A punctal plug, also known as tear duct plug or lacrimal plug, is a small

medical device A medical device is any device intended to be used for medical purposes. Significant potential for hazards are inherent when using a device for medical purposes and thus medical devices must be proved safe and effective with reasonable assura ...

that is inserted into the

tear duct The nasolacrimal duct (also called the tear duct) carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards. The o ...

(puncta) of an

eye An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system. In higher organisms, the ey ...

to block the duct. This prevents the drainage of liquid from the eye. They are used to treat

dry eye Dry eye syndrome, also known as keratoconjunctivitis sicca, is the condition of having dry eyes. Symptoms include dryness in the eye, irritation, redness, discharge, blurred vision, and easily fatigued eyes. Symptoms range from mild and occas ...

Artificial tear Artificial tears are lubricating eye drops used to relieve dryness and irritation of the ocular surface. Dry eye syndrome ( keratoconjunctivitis sicca) is a common ocular surface disorder and is characterized by disruption of the tear film and ...

s are usually still required after punctal plug insertion.

Types

A temporary punctal occlusion can be inserted and tried first. These are made of

collagen Collagen () is the main structural protein in the extracellular matrix of the connective tissues of many animals. It is the most abundant protein in mammals, making up 25% to 35% of protein content. Amino acids are bound together to form a trip ...

and are dissolvable. This is to ascertain that permanent ones will not cause excessive tearing (lacrimation). Permanent punctal plugs are usually made of

silicone In Organosilicon chemistry, organosilicon and polymer chemistry, a silicone or polysiloxane is a polymer composed of repeating units of siloxane (, where R = Organyl group, organic group). They are typically colorless oils or elastomer, rubber ...

. These are available in various sizes. For maximum effectiveness, the largest size that fits should be used. These are more effective than collagen plugs. They can sometimes become loose and fall out, in which case they can be replaced. Some plugs are made of thermally reactive material. Some of these are inserted into the punctum as a liquid, and then harden and conform to the individual's drainage system. Others start out rigid and become soft and flexible, adapting to the individual's punctal size after they are inserted.

Risks

The risks of punctal plugs are fairly small. There is a risk of eye irritation, excessive tearing (lacrimation), and, in rare cases, infection. A large silicone plug can cause slight pain upon blinking after insertion. This discomfort may stop within a week.

Efficacy

systematic review A systematic review is a scholarly synthesis of the evidence on a clearly presented topic using critical methods to identify, define and assess research on the topic. A systematic review extracts and interprets data from published studies on ...

by the

Cochrane Collaboration Cochrane is a British international charitable organisation formed to synthesize medical research findings to facilitate evidence-based choices about health interventions involving health professionals, patients and policy makers. It includes ...

sought to assess the safety and efficacy of punctal plugs for the management of dry eye. The review included eighteen studies, testing punctal plugs of different materials, and comparing them to other treatments for dry eye. Overall there were mixed results; punctal plugs did not show consistent improvement of dry eye symptoms compared to the comparison group at follow-up. There was little evidence of differences between silicone and collagen or acrylic punctal plugs. Punctal plugs may be more effective than oral

pilocarpine Pilocarpine, sold under the brand name Pilopine HS among others, is a lactone alkaloid originally extracted from plants of the Pilocarpus genus. It is used as a medication to reduce pressure inside the eye and treat dry mouth. As an eye drop ...

, but may be less effective than artificial tears. Some adverse outcomes from participants included spontaneous plug loss, epiphora, ocular irritation, foreign body sensation, and local inflammatory reaction.

Alternatives

If punctal plugs are at least partly effective, thermal, electric or radiofrequency (RF)

cauterization Cauterization (or cauterisation, or cautery) is a medical practice or technique of burning a part of a body to remove or close off a part of it. It destroys some tissue in an attempt to mitigate bleeding and damage, remove an undesired growth, o ...

of puncta can be performed with local sedation. RF cauterization is an

electrosurgery Electrosurgery is the application of a high-frequency (radio frequency) alternating polarity, electrical current to biological tissue as a means to cut, coagulate, desiccate, or fulgurate tissue.Hainer BL, "Fundamentals of electrosurgery", '' ...

office procedure that can be performed by an

oculoplastic Oculoplastics, or oculoplastic surgery, includes a wide variety of surgical procedures that deal with the orbit (eye socket), eyelids, tear ducts, and the face. It also deals with the reconstruction of the eye and associated structures. Training ...

eye surgeon using a

hyfrecator A hyfrecator is a low-powered medical apparatus used in electrosurgery on conscious patients, usually in an office setting. It is used to destroy tissue directly, and to stop bleeding during minor surgery. It works by emitting low-power high-freq ...

. Before the cauterization, the surgeon tests for the effectiveness of the local sedation. Depending upon the type and depth of the cauterization, it is effective for a few months to a few years, by which time the puncta can possibly regrow and reopen. In this case, cauterization can be repeated. It initially offers complete closure of the duct. It also obviates the need for a punctal plug. It is performed for one punctum per appointment. Depending on the need, it can eventually be done for all four puncta. Cauterization can result in temporary redness for a few hours which is caused by the avoidable use of a protective cover over the eye. Any lasting sensitivity as a result of this cover can be reversed using short-term use of steroid eye drops such as those containing

loteprednol Loteprednol (formulated as the ester loteprednol etabonate) is a topical corticosteroid used to treat inflammations of the eye. It is marketed by Bausch and Lomb as Lotemax and Loterex. It was patented in 1980 and approved for medical use in ...

Other indications for use

Sjögren syndrome Sjögren is a Swedish surname. Notable people with the surname include: * Anders Johan Sjögren (1794–1855), Finnish linguist, historian, ethnographer and explorer * Ann Mari Sjögren, Swedish fantasy artist and illustrator * Christer Sjögren, ...

for management/treatment of

dry eyes Dry eye syndrome, also known as keratoconjunctivitis sicca, is the condition of having dry eyes. Symptoms include dryness in the eye, irritation, redness, discharge, blurred vision, and easily fatigued eyes. Symptoms range from mild and occa ...

References

External links

Punctal plugs and Intracanalicular plugs
{{DEFAULTSORT:Punctal Plug Implants (medicine) Medical equipment Ophthalmology