VOLUMETRIC SINGLE-LAYER INNER RETINAL ANALYSIS IN PATIENTS WITH HYDROXYCHLOROQUINE TOXICITY.
OBJECTIVE
To compare retinal layer volumes using spectral-domain optical coherence tomography between eyes with hydroxychloroquine (HCQ) toxicity and control eyes.


METHODS
Using a previously validated algorithm, volumetric analysis from the macular cube scan of the ganglion cell layer, inner plexiform layer, inner nuclear layer, and outer retina (outer plexiform layer to retinal pigment epithelium) layers were compared in three sets of patients: patients with a clinical diagnosis of HCQ toxicity, age-matched patients taking HCQ but not manifesting overt toxicity, and age-matched control patients.


RESULTS
There were 14 patients in each group. The ganglion cell layer (P = 0.01), inner plexiform layer (P = 0.004), inner nuclear layer (P < 0.001), and outer plexiform layer to retinal pigment epithelium (P < 0.001) volumes were significantly reduced in HCQ toxicity eyes relative to the HCQ exposure eyes. There were no significant inner and outer retinal volume differences between the HCQ exposure group and group with no HCQ use (P > 0.05 for all layers). Increasing disease severity correlated with increasing volume loss in the inner retina (2.27 mm in early disease vs. 1.78 mm in advanced retinopathy, P = 0.02).


CONCLUSIONS
Hydroxychloroquine toxicity seems to result in both outer and inner retinal volumetric thinning compared with age-matched control patients and patients taking HCQ but not manifesting toxicity.
*Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio; and †Case Western Reserve School of Medicine, Cleveland, Ohio.
Yasha S
YS
Modi
Adrian
A
Au
Vishal S
VS
Parikh
Justis P
JP
Ehlers
Andrew P
AP
Schachat
Rishi P
RP
Singh
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000962:Antimalarials / Q000633:toxicity*; D018501:Antirheumatic Agents / Q000633:toxicity*; D005260:Female; D006801:Humans; D006886:Hydroxychloroquine / Q000633:toxicity*; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D012164:Retinal Diseases / Q000139:chemically induced / Q000175:diagnosis*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology
D000962:Antimalarials; D018501:Antirheumatic Agents; D006886:Hydroxychloroquine