Intraocular pressure and proptosis in 95 patients with Graves ophthalmopathy.

PURPOSE

To study the cause of ocular hypertension in patients with Graves ophthalmopathy.

METHODS

Intraocular pressure was measured in 190 eyes of 95 patients (mean age, 42 years; range, 11 to 86 years) with Graves ophthalmopathy. In six eyes (four patients), changes in intraocular pressure were also analyzed upon orbital decompression.

RESULTS

The mean intraocular pressure +/- SD in 190 eyes was 18.36 +/- 4.02 mm Hg (range, 10 to 34 mm Hg). The intraocular pressure in 42 of the 190 eyes was 21 mm Hg or more. The intraocular pressure in 76 eyes with proptosis of 19 mm or more was 19.96 +/- 4.49 mm Hg (range, 14 to 34 mm Hg), whereas the intraocular pressure in 114 eyes with proptosis of less than 19 mm was 17.08 +/- 3.38 mm Hg (range, 10 to 28 mm Hg). The difference in the values between these two groups is statistically significant (two-tailed t test, P < .001). The mean intraocular pressure in six eyes decreased from 23.23 to 18.82 mm Hg upon orbital decompression, a difference that was statistically significant (two-tailed paired t test, P < .001). The coefficient of outflow facility was normal in these six eyes.

CONCLUSION

These findings suggest that ocular hypertension in patients with Graves ophthalmopathy is caused, in part, by increased intraorbital pressure associated with proptosis.