Retinal nerve fibre layer thickness measurements in patients using chloroquine

Clin Exp Ophthalmol. 2006 Mar;34(2):130-6. doi: 10.1111/j.1442-9071.2006.01167.x.

Abstract

Purpose: Previous investigations have suggested that initial retinal damage from chloroquine toxicity occurs in ganglion cells, and other ocular tissues are affected only later on. The aim of this study was to evaluate retinal nerve fibre layer (RNFL) thickness measurements, as assessed by scanning laser polarimetry, in a group of patients under long-term treatment with chloroquine.

Methods: This case-control study included 34 patients using chloroquine diphosphate and 34 age-matched healthy subjects with no previous history of chloroquine intake. All subjects underwent RNFL assessment using the GDx -- Nerve Fibre Analyser (software v.2.0.01). One eye of each patient was randomly selected for statistical analysis. Peripapillary RNFL measurements were compared between the two groups. For patients using chloroquine, the correlation between RNFL measurements and chloroquine dosage was assessed.

Results: Mean +/- SD RNFL thickness for patients using chloroquine was 60.6 +/- 11.2 microm, 65.6 +/- 13.2 microm, 74.8 +/- 14.8 microm, 36.2 +/- 9.6 microm and 43.8 +/- 7.9 microm for global, superior, inferior, temporal and nasal regions, respectively. In the control group, the corresponding values were 72.1 +/- 12.7 microm, 79.9 +/- 14.8 microm, 88.3 +/- 14.0 microm, 44.2 +/- 12.8 microm and 49.7 +/- 11.9 microm. Mean RNFL thickness measurements from patients using chloroquine were significantly different from those in the control group in all regions (P < 0.05). Thinner RNFL thickness measurements were associated with higher daily dosages of chloroquine.

Conclusion: Patients under long-term chloroquine treatment had significantly lower RNFL thickness measurements than healthy subjects, and the RNFL loss was correlated to chloroquine daily dosage.

MeSH terms

  • Adult
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use*
  • Arthritis, Rheumatoid / drug therapy
  • Body Weights and Measures
  • Case-Control Studies
  • Chloroquine / adverse effects
  • Chloroquine / analogs & derivatives*
  • Chloroquine / therapeutic use
  • Diagnostic Techniques, Ophthalmological
  • Female
  • Humans
  • Lupus Erythematosus, Systemic / drug therapy
  • Male
  • Nerve Fibers / drug effects
  • Nerve Fibers / pathology*
  • Optic Nerve / drug effects
  • Optic Nerve / pathology*
  • Retinal Diseases / chemically induced
  • Retinal Diseases / diagnosis*
  • Retinal Ganglion Cells / drug effects
  • Retinal Ganglion Cells / pathology*
  • Visual Field Tests
  • Visual Fields

Substances

  • Anti-Inflammatory Agents, Non-Steroidal
  • chloroquine diphosphate
  • Chloroquine