A punctal plug is a small medical device

Medical device

A medical device is a product which is used for medical purposes in patients, in diagnosis, therapy or surgery . Whereas medicinal products achieve their principal action by pharmacological, metabolic or immunological means. Medical devices act by other means like physical, mechanical, thermal,...

 that is inserted into the tear duct

Nasolacrimal duct

The nasolacrimal duct carries tears from the lacrimal sac into the nasal cavity. Excess tears flow through nasolacrimal duct which drains into the inferior nasal meatus...

 (puncta) of an eye

Human eye

The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...

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

Keratoconjunctivitis sicca

Keratoconjunctivitis sicca , also called keratitis sicca, xerophthalmia or dry eye syndrome is an eye disease caused by eye dryness, which, in turn, is caused by either decreased tear production or increased tear film evaporation. It is found in humans and some animals...

.

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

Collagen

Collagen is a group of naturally occurring proteins found in animals, especially in the flesh and connective tissues of mammals. It is the main component of connective tissue, and is the most abundant protein in mammals, making up about 25% to 35% of the whole-body protein content...

 and are dissolvable. This is to ascertain that permanent ones will not cause excessive tearing.

Permanent punctal plugs are usually made of silicone

Silicone

Silicones are inert, synthetic compounds with a variety of forms and uses. Typically heat-resistant and rubber-like, they are used in sealants, adhesives, lubricants, medical applications , cookware, and insulation....

. 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 they 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.

Artificial tear

Artificial tear

Artificial tears are lubricant eye drops used to treat the dryness and irritation associated with deficient tear production in keratoconjunctivitis sicca . They are also used to moisten contact lenses and in eye examinations....

s are usually still required after punctal plug insertion. If punctal plugs are effective, thermal or electric cauterization

Cauterization

The medical practice or technique of cauterization is the burning of part of a body to remove or close off a part of it in a process called cautery, which destroys some tissue, in an attempt to mitigate damage, remove an undesired growth, or minimize other potential medical harmful possibilities...

of puncti can be performed.

Risks

The risks of punctal plugs are fairly small. There is a risk of eye irritation, excessive tearing, and, in rare cases, infection. Some doctors require a disclaimer to be signed prior to the insertion of a plug.

A large silicone plug can cause slight pain upon blinking after insertion. This discomfort may stop within a week.

External links

• Punctal plugs and Intracanalicular plugs