Steroid Injections vs. Standard Treatment for Macular Edema Due to Retinal Blood Vessel Blockage
Status:
Completed
Trial end date:
2005-11-01
Target enrollment:
Participant gender:
Summary
This study will compare the safety and effectiveness of two treatments-injections of
triamcinolone acetonide into the eye vs. standard laser therapy-for macular edema (swelling
in the center of the retina) that is caused by blockage in a retinal blood vessel. Edema
caused by blockage in a large vessel is called central retinal vein occlusion (CRVO). Edema
caused by blockage in a smaller vein is called branch retinal vein occlusion (BRVO).
Triamcinolone acetonide is a steroid drug that reduces swelling; the Food and Drug
Administration has approved it for injection into joints and muscles to treat inflammatory
conditions.
Patients 18 years of age and older with macular edema due to CRVO or BRVO of between 3 and 18
months' duration may be eligible for this study. Candidates are screened with a medical
history, blood pressure measurement, and urine pregnancy test for women who can become
pregnant. Screening also includes the following procedures:
- Eye examination to assess visual acuity and eye pressure, and to examine the cornea,
lens, and retina. The pupils are dilated with drops for this examination.
- Fluorescein angiography to evaluate the eye's blood vessels. A yellow dye is injected
into an arm vein and travels to the blood vessels in the eyes. Pictures of the retina
are taken using a camera that flashes a blue light into the eye. The pictures show if
any dye has leaked from the vessels into the retina, indicating possible blood vessel
abnormality.
- Optical coherence tomography to measure retinal thickness. The eye is examined with a
machine that produces cross-sectional pictures of the retina. The patient is seated in
front of a machine and looks at a pattern of flashing and rotating red and green lights,
first with one eye and then with the other.
- Fundus photography to help evaluate the status of the retina and changes that may occur
in the future. Photographs of the retina are taken using a camera that flashes a bright
light into the eye.
Participants are randomly assigned to receive triamcinolone injections or standard treatment.
Triamcinolone is given in either a 1-mg or 4-mg dose. Standard treatment for CRVO and for
BRVO with excessive blood in the retina is observation. Standard treatment for BRVO without
excessive blood is laser therapy. Patients with BRVO who do not qualify for laser therapy
when they enter the study may have it later if blood clears enough to permit treatment. The
procedures for triamcinolone injections and laser therapy are as follows:
- Triamcinolone acetonide: The eye is numbed with anesthetic drops and the study drug is
injected into the vitreous, the jelly-like substance located between the back of the
lens and the retina. Patients apply antibiotic drops at home for 3 days following the
procedure.
- Laser treatment: The eye is numbed with anesthetic drops and a special contact lens is
placed on the eye during the laser beam application.
All patients are followed every 4 months for 3 years. Additional visits may be scheduled if
needed. Patients who receive triamcinolone injections are also examined within 1 week of each
injection and 1 month after each injection. At the 4-month visits patients undergo repeat eye
examination and fundus photography. Optical coherence tomography is done at some visits, and
fluorescein angiography is repeated at months 4, 12 and 24. Blood pressure is measured at
months 12, 24 and 36. Patients may be retreated with triamcinolone injections or laser
therapy as often as every 4 months, depending on their response to treatment.