Disparity between visual fields and optical coherence tomography in hydroxychloroquine retinopathy.
OBJECTIVE
American Academy of Ophthalmology recommendations for screening for hydroxychloroquine (HCQ) retinopathy advise objective measures, such as spectral-domain optical coherence tomography (SD-OCT) and multifocal electroretinography (mfERG) along with visual fields. However, the relative sensitivity and specificity of screening tests have not been fully resolved. We characterize a subset of patients with toxicity who show unusual disparity between fields and SD-OCT and thus have implications for screening practice.


METHODS
Review of charts and clinical data.


METHODS
Patients at Stanford and Kaiser Permanente who had used HCQ with greater than 1000 g cumulative exposure. There were more than 2000 such individuals, among whom 150 had clear evidence of toxicity.


METHODS
Patients were evaluated by visual fields (10-2 white Swedish Interactive Threshold Algorithm pattern deviation plots), SD-OCT, and sometimes mfERG or fundus autofluorescence.


METHODS
Relative findings on visual fields in comparison with SD-OCT.


RESULTS
There were 11 patients among those with HCQ toxicity who had parafoveal ring scotomas but a normal-appearing SD-OCT. None had a history of macular disease or evidence for any other cause of bull's eye maculopathy. Conversely, all cases with a clear degree of parafoveal damage on SD-OCT showed at least some focal spots of parafoveal field loss.


CONCLUSIONS
Approximately 10% of patients with early HCQ toxicity showed prominent ring scotomas on field testing without obvious SD-OCT abnormality. This should encourage the inclusion of visual fields as a key screening tool, even when SD-OCT (a more specific and objective test) also is performed. The combination of visual fields and SD-OCT gives both sensitivity and specificity while avoiding unnecessary stoppage of the drug.
Department of Ophthalmology and Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California. Electronic address: marmor@stanford.edu.
Michael F
MF
Marmor
Department of Ophthalmology, Kaiser Permanente Northern California, Redwood City Medical Center, Redwood City, California.
Ronald B
RB
Melles
D000368:Aged; D018501:Antirheumatic Agents / Q000009:adverse effects*; D004596:Electroretinography; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D006886:Hydroxychloroquine / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012164:Retinal Diseases / Q000139:chemically induced / Q000175:diagnosis*; D012189:Retrospective Studies; D012607:Scotoma / Q000139:chemically induced / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000139:chemically induced / Q000175:diagnosis*; D058609:Visual Field Tests; D014794:Visual Fields / Q000187:drug effects*
D018501:Antirheumatic Agents; D006886:Hydroxychloroquine