1-12. PROCEDURES ON THE EYEBALL
a. Enucleation. This is excision of the eyeball and its muscles, with or without
introduction of an implant (device made of glass or plastic used to prevent unsightly
appearance of the eye and to form, a base for a prosthesis). Enucleation is sometimes
indicated as treatment following penetrating or crushing wounds of the eyeball, and
upon diagnosis of certain other conditions--especially the threat of sympathetic
ophthalmia. (Sympathetic ophthalmia is bilateral inflammation of the entire uveal tract.)
The condition is nearly always secondary to a perforating wound of the eye.
Sympathetic ophthalmia nearly always progresses to blindness unless the injured eye
("exciting eye") is removed before the disease is well underway in the other eye
("sympathizing eye"). The anesthesia of choice for this operation is general anesthesia.
b. Evisceration. In contrast to enucleation, evisceration is excision of the
cornea and removal of all contents of the globe, leaving the scleral shell and muscles
intact. The procedure is indicated following injury when a virulent organism invades the
eye. Evisceration provides less danger of the transmission of infection to the brain than
does enucleation. General anesthesia is usually used for this procedure.
c. Exenteration of Orbit. This is the removal of the entire contents of the orbit
(eye, tendons, muscles, fatty and fibrous tissue). The operation is indicated as
treatment for malignant tumor. General anesthesia is usually given for this procedure.
1-13. PROCEDURES FOR REPAIR OF DETACHED RETINA
a. General. A retinal detachment is a separation of the portion of the retina that
contains the rods and cones from the portion of the retina called the pigment epithelium.
As a result, the rods and cones lose nutrition and cease to function. Thus, the visual
defect will vary with the extent and location of the detachment.
(1) There are many causes for a retinal detachment. These include trauma,
high myopia (causing a thin retina), degeneration, diabetes, infections, and tumors. The
danger of a small retinal detachment is that eventually the entire retina will separate and
the eye will lose all vision.
(2) Blood or fluid may be present as a result of direct or indirect trauma,
severe inflammation, or certain diseases.
b. Operative Procedures.
(1) If the retina is detached as a result of tumor, enucleation may be the
operation indicated.
(2) Retinal detachment due to the presence of blood or fluid offers a choice
of several operative procedures to the surgeon. All operations are based on the
principle of sealing off the area in which the tear has been located, of draining off
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