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Published on: May 25, 2020
Preferential Hyperacuity Perimetry to detect hydroxychloroquine retinal toxicity
Carolyn Anderson1, Patricia Pahk, Gregory R Blaha
1Department of Ophthalmology, Lahey Clinic, Peabody, Massachusetts 01960, USA. carolyn.anderson@lahey.org
Purpose:
To determine if Preferential Hyperacuity Perimetry (PHP) testing can detect the presence of retinal toxicity due to hydroxychloroquine (HCQ) or chloroquine administration.
Methods:
Fifteen patients were divided into three groups. Five patients had confirmed HCQ or chloroquine toxicity, five patients had suspected HCQ toxicity, and five patients had history of long-term use of HCQ or chloroquine but no evidence of toxicity. All patients underwent PHP testing.
Results:
All patients with either known or suspected toxicity based upon standardized visual field testing and/or fluorescein angiography demonstrated significant hyperacuity defects on PHP testing. None of the patients on long-term HCQ therapy, without clinical suspicion of toxicity, demonstrated a PHP hyperacuity defect.
Conclusion:
Results of this pilot study with patients with known or suspected HCQ or chloroquine toxicity suggest that PHP may be a useful adjunct for testing of patients suspicious for toxicity due to these medications. Further testing is warranted.

