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Published on: August 2, 2024
Macular sensitivity changes for detection of chloroquine toxicity in asymptomatic patient
Martina Angi1, Vito Romano, Xavier Valldeperas
1St Paul's Eye Unit, Royal Liverpool University Hospital, Prescot Street, Liverpool, L7 8XP, UK.
Purpose:
To describe the efficacy of microperimetry (MP-1) in detecting early retinal toxicity as a result of chronic use of chloroquine and in monitoring the changes in macular sensitivity in an asymptomatic patient with best-corrected visual acuity of 20/20 bilaterally.
Methods:
A 60-year-old woman presented for routine ocular examination with a medical history of severe rheumatoid arthritis, for which she had been receiving 3 mg chloroquine (CQ) per kilogram for the past 17 years. The patient was asymptomatic with best-corrected visual acuity of 20/20 bilaterally.
Results:
Microperimeter showed loss of sensitivity in the macular region with a dense scotoma within the central 12 degrees (2.80 +/- 4.7 dB right eye and 2.84 +/- 4.7 dB left eye). CQ treatment was discontinued and substituted by Plaquenil.
Conclusions:
Chloroquine retinal toxicity can be recognized in a subclincal form by the presence of early changes in macular sensitivity, detected by MP-1.
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