Introduction
Steroids, especially if taken by mouth or by injections, usually
spell trouble for those with diabetes. It aggravates the blood
glucose and can make your high blood pressure worse. It is therefore
given judiciously.
A form of steroids (TA or Triamcinolone Acetonide) given
intravitreally (i.e. injected via a very fine needle into the back
or vitreous cavity of the eye), however, has been found to improve
the vision in some forms of diabetic maculopathy, otherwise called
Diabetic Macular Edema (DME).
In DME, fat particles and protein as well as fluid leak into the
macular region, an area at the back of the eye responsible for sharp
vision.
How does it work?
The exact mechanism is not known. It is believed that the TA
decreases inflammation and thus reduces the leakage associated with
inflamed small blood vessels (capillaries).
Will it improve my vision?
Vision was found to improve by two lines or more in the vision chart
in about two-thirds of eyes treated with TA injections compared to a
control group who was not treated similarly.
Is the improvement in vision permanent ?
The effects of TA are not permanent. Depending on the dosage given,
the beneficial effects can last from about four to six months.
Vision, unfortunately, can decrease again when the TA effects wear
off.
TA does, however, allow an opportunity to treat an affected eye in
situations where the conventional Argon Laser cannot be used or is
ineffective.
Are there side-effects?
Like any other procedure involving the eye, there are potential side
effects. The most common side-effect after TA injection is that of
raised eye pressure or glaucoma (up to four or five in 10 eyes
treated).
Most eyes with glaucoma, however, can be effectively treated with
eye drops alone (99%). Glaucoma surgery is rarely needed (about 1%).
A more serious potential complication is endophthalmitis, an
infection affecting the eye internally. Although very rare, this is
a potentially sight-threatening occurrence. The TA injection is
therefore given under strict aseptic technique and follow-up checks
are needed.
Conclusion
In some eyes with severe DME or in situations where the conventional
Argon Laser treatment is not possible or effective, this form of
treatment may help some eyes gain useful vision.
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Photo A This shows a
cross-sectional scan of the macula severely affected
by macular edema (dark space) |
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Photo B A/A repeat scan taken four days after the
TA injection. The macular edema (dark space) has decreased
significantly Vision improved by two lines |
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