|
For years, radiation therapy to the eye
has been used to treat eye problems associated with the thyroid
condition Graves' disease. Now a new study questions whether
this treatment is actually useful.
Graves' disease triggers an overproduction
of hormones from the body's thyroid gland, a key regulator
of metabolism and other vital functions. A small percentage
of people with the disorder have a complication called Graves'
ophthalmopathy, which is characterized by bulging eyes, double
vision and other eye problems.
To investigate the effectiveness of radiotherapy
for these eye complications, investigators studied 42 patients
with Graves' ophthalmopathy. The patients exhibited a variety
of symptoms including higher-than-normal volumes of eye muscle
and fat, bulging of the eyes, less eye range of motion and
double vision.
The patients received radiotherapy in
one eye and a "sham" treatment in the other eye.
At follow-up, 3 and 6 months after treatment,
no significant differences
were observed between the treated and untreated eyes.
And this was true regardless of whether
a patient was a smoker. Smokers,
the researchers note, have been found to be more
vulnerable to Graves' ophthalmopathy, and this
could theoretically affect their response to treatment.
Graves' disease is a naturally remitting
condition, and over a period of time many of the symptoms,
including [those related to] the eyes, may improve. This tendency
to natural remission, together with the imprecision of measurements
used in most previous studies, has allowed the perception
to persist that the treatment is effective.
Overall, in 44% of the patients, the eye
treated with radiotherapy did not appear any different from
the non-treated eye. In about 27%
of patients the treated eye appeared better than
the untreated eye, but in 30%
it appeared worse.
Ophthalmology
September 2001;108:1523-1534
| 