Triamcinolone Acetonide Injections to Treat Diabetic Macular Edema
Status:
Completed
Trial end date:
2006-05-01
Target enrollment:
Participant gender:
Summary
This study will evaluate which of the three following treatment options is better for
diabetic macular edema: laser alone, steroid injection alone, or steroid injection followed
by laser. Macular edema is a swelling in the small central part of the retina - the part of
the retina that is used for sharp, straight-ahead vision. Laser treatment is the only
treatment that has been proven to be beneficial for diabetic macular edema. It reduces the
swelling and lessens the chance of further vision loss, but it does not improve vision.
Triamcinolone is a steroid drug that decreases inflammation and scarring. Injections of the
drug have decreased macular edema in some patients and improved vision. Swelling may return,
requiring repeat injections, and it is not known if the vision improvement is permanent. This
3-year study will examine and compare the benefits and side effects of both treatments, alone
and in combination.
Patients 18 years of age and older with diabetic macular edema may be eligible for this
study. Participants undergo the following tests and procedures.
At the beginning of the study:
- Blood tests to measure HbA1C (measure of diabetes control).
- Measurement of blood pressure.
- Eye examination to assess visual acuity (eye chart test) and eye pressure, and to
examine pupils, lens, retina and eye movements. The pupils are dilated with drops for
this examination.
- Optical coherence tomography (OCT) to measure retinal thickness. This test shines a
light into the eye and produces cross-sectional pictures of the retina. These
measurements are repeated during the study to determine if retinal thickening is getting
better or worse, or staying the same.
Photographs of the retina and lens. A special camera with bright flashes is used to take
these photographs.
Treatments
Some patients will have one eye treated and some patients will have both eyes treated. The
treatment for a given individual is determined by chance:
- Triamcinolone acetonide injection alone. The steroid is injected in the tissue around
the eye. Two injection procedures are used in the study, differing in their location and
dose. Numbing drops are placed over the area to be injected and the steroid is injected.
- Laser treatment alone. The surface of the eye is numbed with drops and a contact lens is
placed on the eye during the laser beam application. Before the treatment, patients may
have fluorescein angiography, in which pictures of the retina are taken using a yellow
dye. The dye is injected into a vein and travels to the blood vessels in the eye. The
camera flashes a blue light in the eye and takes pictures that show the amount of dye
leakage into the retina. Treatments may be repeated at several visits.
- Triamcinolone acetonide plus laser treatment. Patients who receive both the steroid
injection and laser have the steroid injection first and the laser treatment 1 month
later.
Follow-up
Patients return to the clinic for follow-up visits at 1, 2, 4, 8, 12, 24 and 36 months, or
more often if needed, after the initial treatment for an eye exam, measurement of visual
acuity, and OTC. Photographs of the retina are taken at the 4- and 8-month visits and at the
1-, 2- and 3-year visits. Fluorescein angiography may be done at 4 months. Blood pressure is
measured at the 1-, 2- and 3-year visits, and an HbA1c blood test is done at 4 and 8 months
and at the yearly visits. Participants may be asked to complete a questionnaire once a year
about their vision and medical condition. Treatment options are discussed at the 4- and
8-month visits.