HEAVY IRIDOCORNEAL ANGLE HYPERPIGMENTATION AND GLAUCOMA ASSOCIATED WITH FLUOROSIS

Endemic fluorosis is a chronic crippling skeletal and dental disease caused by ingestion or inhalation of large amounts of fluoride. Although the prevalence of this disease has decreased considerably, it still occurs in some parts of the world. Our province Isparta is a naturally occurring endemic fluorosis area. The aim of this study is to investigate the ocular manifestations of the disorder in a group of patients with fluorosis. Fifty (32 F, 18 M) consecutive patients, ages ranging between 29 and 74 years (54.44±12.28), with endemic fluorosis constituted the study group. Age and sex matched fifty consecutive patients without clinical findings of fluorosis were selected as controls. Patients with and without fluorosis underwent a routine ophthalmologic examination. To assess the levels of hyperpigmentation in anterior chamber angle, we constituted a grading system (from 1 to 4) based on selected brownish colors from Pantone® Color Formula Guide. The differences between two groups with respect to serum, urine, and water fluoride levels are statistically significant (for all p<0.001). With respect to iridocorneal angle hyperpigmentation (ICA HP) grades, the difference between fluorosis and control group was statistically significant (p<0.001). In the fluorosis group, we observed eight cases (16%) of open angle glaucoma (OAG). Remarkably, ICA HP grade was 4+ in six out of eight cases; this finding was statistically significant (p<0.001). The remaining two showed grade 1+ ICA HP. Difference between number of cataracts or previous cataract operations of the two groups [fluorosis group: 15 cases (30%), controls: 12 cases (24%)] was not statistically significant (p>0.05). We suggest that heavy trabecular hyperpigmentation appearance may be a feature of endemic fluorosis. This disorder should be kept in mind in differential diagnosis of pathologic trabecular hyperpigmentation in patients with fluorosis and without the causes and symptoms of iris pigment dispersion. We also propose that endemic fluorosis may lead or augment the severity of glaucoma. Further studies are warranted in order to comprehend the exact mechanism of trabecular changes in patients with endemic fluorosis.