Occasionally, a retinal detachment is so complicated and severe
that it cannot be treated with either standard scleral buckling
surgery or pneumatic retinopexy. In such cases, vitreous surgery
to reattach the retina may be necessary. Vitreous surgery is
performed in the hospital, often under general anesthesia. The
vitreous is removed and, therefore, this procedure is called
"vitrectomy". The surgeon uses a fiberoptic light to illuminate
the inside of the eye and other instruments inside the eye, such
as forceps, and scissors, to do the surgery. The vitreous is
replaced during the operation with either clear fluid that is
compatible with the eye, or with air that completely fills the
eye. Over time, this fluid (or air) is absorbed by the eye and
is replaced by the eye's own fluid; the eye does not replace the
vitreous itself. The lack of vitreous does not affect the
functioning of the eye.
Vitrectomy is required for retinal reattachment in a variety of
conditions. For example, scar tissue may grow on the vitreous or
surface of the retina and pull on the retina and detach it.
Occasionally, something is in the vitreous, such as blood, that
prevents the passage of light through the eye to the retina. The
most common conditions requiring vitrectomy are vitreous
hemorrhage with retinal detachment, proliferative
vitreoretinopathy, giant retinal tears, diabetic retinopathy with
vitreous hemorrhage and/or traction retinal detachment,
epiretinal membranes (macular pucker), intraocular infection
(endophthalmitis), trauma, and intraocular foreign body. Each of
these conditions will be discussed in the following sections.
In a vitrectomy, instruments are passed through the sclera into the
vitreous cavity. A variety of instruments can be used to remove
the vitreous gel and any scar tissue that may be growing on the
surface of the retina. A laser probe can be inserted into the
eye so that laser treatment can be done during surgery.
Vitrectomy can be combined with the placement of a scleral
buckle. Occasionally, air, gas, or silicone oil is placed in the
vitreous cavity. These materials hold the retina in place
against the wall of the eye while the laser scars are taking hold.
After this surgery, it may be important for the patient to
maintain a cetain position of the head, which is often face-down
(prone) position. Eventually, the air or gas is absorbed by the
body and replaced by fluid produced by the eye. If silicone oil
has been used, it usually must be removed at a later time with
another surgical procedure. Vitreous surgery usually lasts one
to two hours but, with very severe and dificult problems, may take
many hours. Following surgery, the patient may experience some
discomfort and a scratchy sensation in the eye, but significant
pain is unusual. If it occurs, the surgeon should be told
immediately.
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