Multifocal electroretinography evaluation for early detection of retinal dysfunction in patients taking hydroxychloroquine.
OBJECTIVE
To evaluate macular function using multifocal electroretinography (mfERG) in a cohort of asymptomatic patients taking hydroxychloroquine and a patient with maculopathy secondary to hydroxychloroquine treatment.


METHODS
mfERG recordings were obtained for both eyes of 11 patients taking hydroxychloroquine without clinical signs of toxicity and 1 patient with toxic maculopathy. Initially, the classic m-sequence paradigm for the first-order kernel (103 hexagons; 2.7 candela x seconds/m2 peak luminance) was recorded. After that, another special stimulation mode was applied, which emphasized second-order adaptational effects (modulated multifocal flashes with interleaved global flashes, MF0F0 paradigm).


RESULTS
The patient with toxic maculopathy and one patient without toxicity had multiple areas of decreased retinal responses bilaterally (classic m-sequence). The patient with toxicity and another three patients without toxicity presented with multiple areas of decreased retinal function in both eyes with the second-order component of the MF0F0 paradigm. Repeated recordings of 1 patient 8 months after the initial recording demonstrated evidence for reproducibility of the second-order adaptive effects.


CONCLUSIONS
Clinically asymptomatic patients receiving hydroxychloroquine treatment can have substantial local decreases in their retinal function, as reflected by the changes in mfERG recordings, possibly indicating a preclinical stage of drug-related toxicity.
Penrose
Philip J
PJ
Department of Ophthalmology, California Pacific Medical Center, PO Box 7999, San Francisco, CA 94120, USA. philip@ski.org
Tzekov
Radouil T
RT
Sutter
Erich E
EE
Fu
Arthur D
AD
Allen
Arthur W
AW
Fung
Wayne E
WE
Oxford
Karen W
KW
D000328:Adult; D000368:Aged; D018501:Antirheumatic Agents / Q000009:adverse effects*; D004596:Electroretinography / Q000379:methods*; D005260:Female; D006801:Humans; D006886:Hydroxychloroquine / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000187:drug effects* / Q000503:physiopathology; D012164:Retinal Diseases / Q000139:chemically induced* / Q000175:diagnosis* / Q000503:physiopathology; D012607:Scotoma / Q000139:chemically induced / Q000175:diagnosis / Q000503:physiopathology
D018501:Antirheumatic Agents; D006886:Hydroxychloroquine