Posts Tagged ‘cosmetic’

Tears in the Artificial Eye Socket

Wednesday, October 16th, 2013

Coating the inner and outer surfaces of the artificial eye is a tear film. People normally blink the eyelids about every six seconds to replenish this tear film. Tears have four main functions on the artificial eye:

  • wetting the conjunctival lining of the socket, preventing damage due to dryness,
  • creating a smooth optical surface on the front of the microscopically irregular acrylic surface,
  • providing lubrication and acting as a vehicle to remove debris from the prosthetic surface, and
  • containing an enzyme called “lysozyme” which destroys bacteria.

The tear film resting on the prosthetic surface has three layers:

  • Lipid layer,
  • Aqueous Layer, and
  • Mucin Layer.

The top layer of the tear film is the lipid or oily layer. This layer prevents the aqueous layer beneath it from evaporating, as well as preventing the tears from flowing over the edge of the lower eyelid.

Below the lipid layer is located the aqueous layer of the tear film. This middle layer is the thickest of the three tear layers. The aqueous fluid contains salts, proteins and lysozyme.

The bottom layer is the mucin layer. This layer adheres to the “hydrophobic” (water-repelling) acrylic surface of the prosthesis. Therefore, for a tear layer to be able to remain on the prosthetic surface without rolling off, the “hydrophilic” (water-attracting) mucin layer is necessary.

A deficiency of any of the three layers of the tear film can lead to a “dry eye” condition, causing anything from mild eye irritation to severe pain. Interestingly, in some cases, excessive tearing or watering of the eyes can be a symptom of a dry eye condition. This is because when, for whatever reason, there is an inadequate normal tear layer on the eye, irritation results; the latter causes an overproduction of the lacrimal gland and a flooding of lacrimal fluid into the eye.

Besides excessive tearing, symptoms associated with dry eyes can include the following:

  • eye irritation, scratchiness, grittiness, or pain,
  • redness of the conjunctival tissue,
  • a burning sensation in the eye,
  • a feeling of something in the eye,
  • eyes that feel “glued shut” after sleeping,
  • excess mucosal drainage, and
  • discomfort wearing the prosthesis.

There can be multiple causes of a dry eye condition for a prosthetic eye wearer:

  • lid or blinking problems,
  • reading or working at a computer screen for long periods of time,
  • medications like antihistamines, oral contraceptives, beta blockers, diuretics, tranquilizers, pain relievers, or antidepressants,
  • a dry climate (including heating and air conditioning in a home, airplane, or hotel room), wind, UV radiation, tobacco smoke, and dust,
  • diseases such as rheumatoid arthritis, Sjogren’s syndrome, keratoconjunctivitis sicca, xerophthalmia, lupus erythematosus, Grave’s disease, diabetes, or scleroderma
  • hormonal changes accompanying menopause,
  • chemical, radiation, or thermal burns to the eye,
  • vitamin A deficiency,
  • aging, since the tear glands produce fewer tears as we age,
  • protein adhesion to prosthetic surface,
  • scratches on the prosthetic surface, or
  • ill-fitting prosthesis.

A dry eye problem often can be relieved with the use of lubricating eyedrops, which are instilled daily or as needed onto the prostheic surface. These types of drops can soothe the socket, moisturize dry spots, supplement tears, and protect conjunctival tissue from further irritation. They provide comfort and a nice shiny, even tear layer over the prosthesis. They have a higher viscosity than natural tears, so they need to be insilled less frequently, often just once or twice per day. The lubrication allows for easier blinking, less drainage from the socket, and a very natural appearance.

Soothing eye drops are also available. These drops have the same viscosity as natural tears, which means they will not be as long lasting as the lubricants, but they do have soothing properties to control allergies, discomfort, itchiness, inflammation and excess mucosal drainage.

Some patients chose to try “artificial tears” type eyedrops to alleviate the sypmtoms of dry eye. These are not very successful because they do not last very long. Most “artificial tear” drops only contain saline, which evaporates very quickly. Some eyedrops contain “vasoconstrictors” (chemicals such as tetrahydrozaline or naphazoline), which constrict the conjunctival blood vessels, thereby reducing the amount of redness on the surface of the eyes. We do not recommend these drops for prosthetic eye wearers as they damage the tissue lining the anophthalmic socket.

Should you have any difficulty with your current regimine, we recommend working with your Ophthalmologist, Optometrist and your Ocularist to determine the root of your symptoms and come up with an appropriate solution. With a healthy fit of your prosthesis, frequent polishing and proper lubrication, your prosthesis should be able to fit and function well. Our goal is to provide our patients with excellent comfort and cosmesis for the most natural, realistic result possible.

Artificial Eye Silicone Lubricants

Wednesday, May 18th, 2011

The lubricants listed below all work to increase the tear film that coats the surface of your prosthetic eye or scleral shell providing more comfort, easier blinking, and a more natural appearance. These lubricants are developed specifically for artificial eyes.

The higher the viscosity, the thicker and longer lasting the lubricant. While this would indicate the highest viscosity lubricant as the best choice, there are a few more factors to consider. The purpose of a lubricant with an ocular prosthesis is to decrease the friction between the eyelids and the prosthetic surface. The best way to decrease friction is to have a smooth prosthetic surface and a good tear film.

The higher viscosity silicone lubricants will boost the outer tear film layer, reducing the evaporation of tears. The soothing drops and lower viscosity lubricants will help boost the aqueous layer of the tear film. In cases where tear production is limited, it may be helpful to use both a lubricant and a soothing drop to replenish the tear film.

Artificial Eye Lubricants

Conditions that deplete tear film and indicate the use of a lubricant:

  • Air Conditioning,
  • Wind,
  • Dry heat,
  • Frigid cold,
  • Smoke,
  • Dust, and
  • Long duration of computer/television use.

Sil-Ophtho Heavy Silicone LubricantOcu-Glide Silicone LubricantSil-Ophtho Silicone LubricantArtificial Eye Lubricant

Myth #3: Artificial Eyes and Scleral Shells Are Cosmetic

Saturday, December 19th, 2009

It is very rare that we come upon an insurance company these days who believes that artificial eyes or scleral shells are cosmetic. The medical necessity for wearing an artificial eye or a scleral shell is to bring about the natural functions of the eye socket. These include proper drainage of tears, creation of tears, protection of the mucosal tissue from drying out and contracting, protection from infection and bringing the phthsical globe or anophthalmic socket back to full size. These reasons alone are enough to provide medical necessity, yet there are of course other benefits to wearing an artificial eye or scleral shell. If you have difficulty with your insurance company considering this a cosmetic procedure, please contact your ocularist for assistance.

Myth #2: Artificial Eyes Do Not Move

Tuesday, December 15th, 2009

It seems that most everybody has a great uncle twice removed who had an “glass eye” that did not move. Contrary to popular belief, most modern artificial eyes and scleral shells move quite well. Movement of the artificial eye is dependent on the movement of the tissue behind the prosthesis and the fit of the prosthesis to this tissue.

Movement could be broken into a couple different categories:

  • Conversational Motility
  • Moderate Motility
  • Extreme Motility
  • Blinking

Motility is the movement of the eye, it includes conversational movement and the movement of the eye all the way to the extremities. Most patients we see experience very good conversational motility. We consider conversational motility to be the horizontal and vertical movement of the prosthesis in the first 10 degrees in each direction. This is the most common movement of the eye, the quick darting movements we all make during interactions with others.

Moderate motility is movement past the 10 degrees of conversational motility, but movement that falls short of the extremities. The degree of motility of an ocular prosthesis is most dependent on the movement of the ocular tissue or ocular implant placed by the surgeon. A nicely placed orbital implant that is central in the orbital cavity and appropriately attached to the major ocular muscles, will be well positioned to provide very good motility. A second factor in motility is the fit of the prosthesis to the orbital implant. Erickson Labs Northwest utilizes the modified impression technique that provides the best possible junction between the front of the orbital tissue and the posterior of the prosthesis, allowing the best possible movement.

Extreme motility is the movement of the eye all the way to the extremities. Extreme motility is more rare due to the anatomical design of the eye socket and the necessary shape of the artificial eye. Extreme motility is often seen in patients wearing a scleral shell over a nice full sized or phthsical globe. Extreme motility can also be seen in patients fitted with a motility implant and integration system such as a titanium peg.

Blinking is the vertical movement of the eyelids, mostly the superior lid, to close and open again. While blinking is not motility, it is very important to the realism of an artificial eye. Blinking functions to wet the ocular surface creating a tear film, promote creation of tears from the eyelid glands, pumping excess tears to the tear ducts, and clearing the ocular surface of debris. Proper blinking is very important to the health of the anophthalmic socket and the normal appearance of an artificial eye.