Retinal Vein Occlusion
The
retina, the
light sensitive tissue that lines the back of the
eye, is nourished by a fragile network of blood
vessels including arteries and veins.
When a vein becomes
blocked or "pinched off", some of the blood flowing
through the vein can hemorrhage out of the vein wall
-- this is called a vein occlusion.
A branch retinal vein
occlusion (BRVO) happens when one of the
smaller retinal veins is blocked. Branch
retinal vein occlusion symptoms range from hardly
noticeable to extensive loss of vision.
A central retinal vein
occlusion (CRVO) happens when the large
retinal vein, responsible for transporting blood out
of the eye, becomes blocked. CRVO symptoms
usually include massive loss of vision.
Both BRVO and CRVO can have associated, secondary
conditions such as: macular edema,
retinal ischemia (lack of blood flow to the retina
tissue)
and neovascular glaucoma.
Retinal vein occlusion should be monitored and
treated by an ophthalmologist.
Avastin for retinal vein occlusion
Ophthalmological use of Anti-VEGF drugs was
originally FDA-approved for the treatment of
neovascular AMD. However, recent studies have
demonstrated that anti-VEGF drugs can be used safely
and effectively for a number of retina conditions
that involve macular edema
as a secondary complication. Retinal vein occlusion
can cause permeability of weakened retinal
blood vessels. The result is blurry vision and
subsequent macular edema.
The CRUISE trial, which was conducted at
The
Methodist Hospital in Houston, demonstrated a
significant increase in visual acuity in CRVO
patients who received Ranibizumab (Lucentis - a
popular anti-VEGF drug) injections every month for
six months. In fact, the data showed a statistically
significant increase in acuity at 1 week after the
first injection. These dramatic results are unheard
of using traditional treatments like prednisone eye
drops.
In addition to the prospective,
randomized CRUISE trial,
Genentech is in a phase III
study of its drug Ranibizumab for treatment of BRVO.
The results of this Lucentis trial will form the
basis of a supplemental biologics license
application being submitted to gain FDA approval for
BRVO treatment.
See also...
Retinal artery
occlusion
Avastin Eye
Injection |
