[Retinal nerve fiber layer alteration in chronic users of chloroquine]

To evaluate the retina nerve fiber layer by laser polarimetry in patients in chronic use of chloroquine.

Forty-four eyes of twenty-two patients were studied. These were in use of chloroquine due to rheumatic diseases during at least one year. As a control group, twenty patients without use of chloroquine with similar characteristics (age, gender and race) were included. Patients who had a family history of ocular hypertension or glaucoma were not included in this group. Both eyes were submitted to analysis of the retina nerve fiber layer with a GDx Nerve Fiber Analyzer.

In 28 eyes (63.6%) of chronic chloroquine users, alterations in more than two parameters by GDx were found. There was alteration in the Deviation from the normal graph with a loss of nerve fibers in 11 eyes (25%). When these results were compared with the control group, there was a significant statistical difference between the following parameters: Superior Ratio, Inferior Ratio, Superior Nasal, Elipse Modulation, The Number, Superior Average and Superior Integral. There was also a significant statistical association between the time of chloroquine use and loss of nerve fiber layer.

From the results the following conclusion can be drawn: the chronic use of chloroquine was associated with alteration of the nerve fiber layer. Thus these results may contribute to early diagnosis of nerve fiber layer loss in chloroquine retinopathy.