- blurred vision
- loss of VISUAL ACUITY
OPHTHALMOSCOPYto examine the interior of the
eye provides the diagnosis.
Treatment Options and OutlookMost often, the preferred treatment for reattach-
ing the retina is surgery. The surgeon may use
laser, photocoagulation (heat), or cryotherapy
(freezing) techniques. Other approaches include
injecting sterile silicone oil into the inner eye or
injecting a sterile gas bubble (pneumotherapy)
into the vitreous humor to hold the retina in place
with pressure. A rapidly reattached retina often
fully recovers without measurable loss of vision.
Delay in reattaching the retina, or when the retina
suddenly and completely detaches, often results in
less successful vision preservation. An untreated
retinal detachment results in permanent, complete
loss of vision in the eye.
Risk Factors and Preventive MeasuresPeople who have moderate to severe myopia
(greater than – 8 diopters) are at increased risk for
retinal detachment because of the eye’s shortened
length. Retinal detachment is also a complication
of LASIK surgery, CATARACT EXTRACTION AND LENS
REPLACEMENT surgery, and serious inflammatory
conditions of the eye such as SCLERITIS. Retinopa-
thy, in which extra blood vessels grow into the
retina, also increases the risk for retinal detach-
ment. Protective eyewear to reduce the risk of
trauma to the eye can prevent trauma-related reti-
nal detachment. In other circumstances, early
detection and reattachment are the most effective
measures to preserve vision.
See also LASER SURGERY; OPERATION; REFRACTIVE
SURGERY; SURGERY BENEFIT AND RISK ASSESSMENT.
retinitis pigmentosa The collective term for a
group of hereditary disorders that result in pro-
gressive loss of vision. Retinitis pigmentosa gener-
ally begins with diminished night vision, as the
degeneration affects primarily the rods (photore-
ceptors responsible for vision in dim light and for
peripheral vision). Eventually the condition pro-
gresses to rods, and then cones, throughout the
RETINA. In most people symptoms begin between
the ages of 10 and 30, with complete loss of vision
by around age 40.
When viewed through the ophthalmoscope,
the areas of degeneration appear darker than the
surrounding areas of retina. The diagnostic path
may also include a DARK ADAPTATION TESTand ELEC-
TRORETINOGRAPHY. There is no known treatment for
retinitis pigmentosa. Several INHERITANCE PATTERNS
are responsible for retinitis pigmentosa; doctors
recommend GENETIC TESTINGand GENETIC COUNSELING
for family members when there is a diagnosis of
this condition. Retinitis pigmentosa also may
accompany a number of other hereditary syn-
dromes.
See also COLOR DEFICIENCY;NIGHT BLINDNESS; OPH-
THALMOSCOPY; RETINOPATHY; VISION IMPAIRMENT.retinoblastoma A cancerous tumor of the RETINA
that most often occurs in children. Most
retinoblastomas are hereditary and develop in
early childhood, usually by age four. Some
retinoblastomas are the result of new germline
mutations though are not hereditary. About 70
percent of retinoblastomas involve only one EYE.
Treatment in such cases is surgery to remove the
EYE(ENUCLEATION), with placement of a PROSTHETIC
EYEfor cosmetic reasons. When retinoblastoma is
bilateral (involves both eyes), treatment attempts
to save vision while eradicating the CANCER. Treat-
ment for bilateral retinoblastoma may include
enucleation of one eye and cryotherapy or photo-
coagulation to reduce as much as possible the
tumor in the other eye, with follow-up
CHEMOTHERAPYor RADIATION THERAPY. Treatment is
successful in about 90 percent of children when
doctors detect the tumor before it metastasized
beyond the eye. However, about 70 percent will
experience second retinoblastomas by adulthood.
See also ADULT SURVIVORS OF CHILDHOOD CANCER;
CANCER TREATMENT OPTIONS AND DECISIONS; GENE TEST-
ING; GENETIC COUNSELING.retinopathy A dysfunction of the RETINA in
which new BLOODvessels grow across the retina’s
surface. This growth causes the death of photore-
ceptors, the specialized cells (rods and cones) in
the retina that receive lightwaves and convert
them to NERVEimpulses for transmission to the
BRAIN. The blood vessels are also delicate and114 The Eyes