Encyclopedia of Health and Medicine

etrobulbar optic neuritis 115
prone to bleeding, which further damages the surface
of the retina. The most common forms of
retinopathy are the following:
• Retinopathy of DIABETES results from chronically
elevated blood GLUCOSE levels. Retinopathy of
diabetes takes one of two forms: proliferative,
in which the new blood vessels that grow
across the retina are unstable and bleed, or
nonproliferative, in which existing blood vessels
deteriorate and form aneurysms that rupture
and bleed. Retinopathy of diabetes
typically develops over decades, is more common
in people who require INSULIN THERAPY, and
is the most common cause of blindness in people
under age 60.
• Retinopathy of prematurity occurs in some
infants born earlier than 32 weeks of gestational
age in whom the retinal blood vessels,
which develop late in gestation, have not yet
formed. In most infants, the blood vessels
resume growth and establish normal retinal
vasculature with no damage to vision. In some
premature infants who have retinopathy, inadequate
blood supply to the retina or abnormal
vessel development can cause RETINAL DETACH-
MENT with resulting VISION IMPAIRMENT.
• Hypertensive retinopathy develops as a consequence
of untreated or poorly managed HYPER-
TENSION (high BLOOD PRESSURE). Blood vessels in
the retina, like blood vessels throughout the
body, become stiff and inflexible as a result of
the continuous pressure. This brittleness makes
them susceptible to rupture, which floods the
retina with blood.
• Central serous retinopathy, in which fluid accumulates
between the retina and the choroid,
causes the retina to swell and lift up from the
choroid.
Symptoms and Diagnostic Path
Most often, retinopathy does not cause symptoms
until eye damage becomes significant. When
symptoms are present, they may include
• blurred or distorted vision
• diminished near vision for reading and other
close focus
• FLASHES and FLOATERS
• sudden loss of vision
OPHTHALMOSCOPY typically reveals discolored
areas of the retina that indicate diminished blood
supply (pale) or bleeding (dark). The ophthalmologist
may also be able to see frank bleeding or
irregularities in the surface of the retina that indicate
accumulated fluid. When the cause of the
retinopathy is hypertension, there may also be
PAPILLEDEMA (swelling of the OPTIC NERVE). Ophthalmoscopy
in combination with health history
generally provides the information the ophthalmologist
needs to make the diagnosis.
Treatment Options and Outlook
Often retinopathy improves on its own, especially
retinopathy of prematurity and central serous
retinopathy. Retinopathy of diabetes or hypertension
typically improves with tighter control of
the underlying condition. When retinopathy
improves, vision may return to its previous state
or damage to vision may be minimal. Retinopathy
that progresses leads to vision impairment, including
total loss of vision. Central serous retinopathy
tends to recur. Proliferative and nonproliferative
retinopathy often require laser treatment.
Risk Factors and Preventive Measures
The key risk factors for most retinopathy are the
underlying health conditions associated with the
retinopathy. Preventive measures emphasize control
of the underlying condition—maintaining stable
blood glucose levels in retinopathy of diabetes,
and healthy blood pressure in retinopathy of
hypertension. Consistent PRENATAL CARE and attention
to maternal health (notably SMOKING CESSA-
TION) help reduce the risk for PREMATURE BIRTH.
Regular ophthalmic examinations can detect
retinopathy in its early stages, allowing therapeutic
interventions to minimize damage to the eye.
See also ISCHEMIC OPTIC NEUROPATHY; RETINITIS PIG-
MENTOSA; TOXIC OPTIC NEUROPATHY.
retrobulbar optic neuritis INFLAMMATION of the
OPTIC NERVE outside the globe of the EYE, between
the eye and the BRAIN. Retrobulbar optic neuritis
can result from INFECTION such as MENINGITIS or
ENCEPHALITIS, as a consequence of toxic exposure,