YAMOUT OPTICAL CENTER

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There Really Is A Difference: Individualized Ocular Prosthetics

"The Modified Impression Method"

    Introduction

  I am frequently asked to indicate to a doctor or patient something about my acrylic eye fitting methods. I am more than happy to do   so. There are several successive steps which I shall briefly describe here.

    Adequate healing is required before fitting the acrylic eye. Schedule   permitting, I will fit the prosthesis six to eight weeks after surgery.

Upon arrival at my office, the patient will complete a registration form   which is the beginning of a record similar to any kept by a medical doctor.

I. Why Take an Alginate Impression?

An impression of the shape of the space of the eye socket is taken with alginate, which gels in about two minutes to the consistency of the white of a hard boiled egg. Any discomfort to the patient is minimal. After removal from the eye socket, a two-piece mold is made using dental stone, a material very much like plaster of paris, around the impression.

Taking an impression affords me the opportunity to design an eye which provides total comfort in most cases and much improved motility. No more removing the eye several times a day, or even once a day. No more mopping up spilled mucous from the socket! No more red, painful tissue.

II. How is the Wax Pattern Made and Used?

After the dental stone has hardened, the impression material is removed. Molten wax is then poured into the mold and allowed to cool and harden. Upon removal from the mold, this wax piece constitutes a pattern (for the artificial eye) which can easily be changed in shape to improve the appearance and comfort to the wearer.

An acrylic iris-cornea, which duplicates the patient's own iris, is chosen and designed into the wax pattern. It can be removed and placed in a different position in the pattern in order to provide the proper direction of gaze, vertical and horizontal positions, the desired prominence to the artificial eye, and to provide the proper eyelid opening. This part of the fitting procedure can take as much as several hours, during which time the patient must remain available at ten to twenty minute intervals for trial fitting.

III. Is Knowledge of Anatomy Necessary?

Yes, it really is. In fact, one of the reasons why the Modified Impression Method is so superior is because it incorporates fitting principles based on a working knowledge of the anatomy of the eye and orbit. Anatomical knowledge helps insure that socket tissues will not be forced into abnormal, irritating, or non-functional positions.

IV. When Does the Prothesis Become Acrylic?

When all the improvements havebeen made in the wax pattern, a new, final mold of that pattern is made, using dental stone, in a brassflask. The wax is then removed; however, the iriscornea is placed back into the mold in precisely the same position it had occupied in the wax pattern. A dough of white acrylic is then packed in the mold and processed under heat and pressure until properly cured.

V. How Is an Acrylic Eye Colored?

As soon as the eye is processed, a thin layer of the acrylic is removed from the front surface in preparation for the coloring. Veins (fine fibers of red embroidery thread) are then painstakingly placed over the surface of the prosthesis in such a manner as to duplicate the veining pattern of the companion eye.

The actual coloring of the eye is done with the greatest care to match the companion eye and to present an appearance of living tissue. This is done by a method devised in October 1976 and used exclusively by those few discriminating ocularists who employ the Modified Impression Method of making artificial eyes. The patient must be present for this part of the work for perhaps two or more hours. At intervals, the painted prosthesis is placed in fhe patient's eye socket, then removed and the coloring altered. This step is repeated until the coloring is fully satisfactory.

VI. At What Point is the Prosthesis Finished?

When the color is judged to be correct, the eye is returned to the final mold and a layer of transparent acrylic is cured on its front surface to protect the color during polishing and wearing. The finished, highly polished prosthesis is then placed in the eye socket and evaluated in all aspects. If it is not correct in every way, changes are made until it meets my quality standards.

VII. How Long Does It Take To Fabricate the Prosthesis?

The procedure normally takes two to two and one-half days. If the eye socket is a very difficult one to fit, it could take an additional one or two days. While most other eye fitters take less time, I have found that far superior prostheses are produced by employing the time involved in the Modified Impression Method.

VIII. Is the Prosthesis Expensive?

Past patients from many different states, and from foreign countries, will attest to the fact that, for almost every person, fine prosthetic work is indeed a priceless blessing! My fees are standard and reasonable for the quality, craftsmanship, and amount of time invested in the designing of this caliber of prosthesis.

IX. Can the Prosthesis be Fitted Over Any Type of Implant?

Absolutely! An added benefit of fitting by this very specific and exacting method makes it possible for surgeons to place special implants in the orbit at the time of eye removal. If such sophisticated implants are fitted by older, traditional methods, there can be danger of pressure necrosis and eventual loss of the implant; whereas, when such implants are fitted by the Modified Impression Method, the likelihood of comfortable retention is nearly one hundred percent.

X. After the Eye is Finished, What Precaution Should the Patient Take?

As one wears the eye over a period of time -six months to one year - minute scratches appear on the surface of the eye (caused by continual lid action against the eye and by handling). These scratches cause the eye to begin to appear dull and can also cause some mattering problems. Therefore, I recommend that the prosthesis be polished in my office at least once a year to assure proper comfort and cosmesis. I also recommend that the patient see his ophthalmologist at least once a year or as often as the doctor directs.

XI. Will a Refit Be Necessary?

Sometimes. A refit may be necessary from time to time due to changes in volume and arrangement of orbital and socket tissues. A refit implies considerable reworking of the eye so that it fits properly once again. Therefore, I will refit only those eyes which I have previously designed and fabricated, as long as the eye is not over seven years old. I am happy to make minor adjustments to an eye which is not over ten years old.

XII. What About a Blind, Unsightly Eye or Phthisical Globe?

It is very common for a patient with an unsightly blind eye or phthisical globe to desire a comfortable "scleral shell." With my exacting methods, this can comfortably and effectively be done providing the cornea is not overly sensitive.

XIV. One Caution

As an ocularist (eye maker). I am not a miracle worker. Because of the abilities, methods, and procedures that I employ, it is true that I can improve, almost without exception, on the prosthesis that a patient has previously been wearing. But it needs to be understood that, especially in the case of severe trauma or scarring, I may not be able to help the patient appear entirely normal again. Always the best that can be done will be done.

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