Abstract
Purpose :
To compare rod system visual fields (VFs) in the central macular region to 10-2 automated VFs and spectral domain optical coherence tomography (OCT) in patients on hydroxychloroquine (HCQ) therapy.
Methods :
10 eyes of 10 patients (17-74 yrs.) treated with HCQ for 1.5-20 years underwent the following recommended screening tests: 10-2 VFs, multifocal electroretinography (mfERG), OCT volume and high resolution horizontal line scans; and short-wavelength fundus autofluorescence (SW-FAF) imaging.[1] Following pupil dilation and dark adaptation for 30 minutes, scotopic VFs were obtained for the eye with better visual acuity using a Medmont dark-adapted chromatic perimeter (size 5 stimulus, 200-ms duration, 505 nm, 56 points, 28x28°). Scotopic VF sensitivities were compared to age-similar normative values. [2]
Results :
Of the 10 patients, 8 had been on HCQ therapy for ≥ 5 years, 6 with a cumulative dose >1000g and a daily dose >5 mg/kg. Four of the 8 patients (3 on >5 mg/kg) had decreased rod sensitivities at eccentricities from 4-10°; deficits were more frequent in the superior VF. Sensitivities were also decreased on the 10-2 VFs in similar regions (Fig 1A, B). Three eyes had abnormal mfERG ring ratio values. Inspection of corresponding OCT b-scans showed outer retinal abnormalities for 3 of the patients that were associated with the 10-2 and scotopic VF defects (Fig 1C). These abnormalities were more noticeable in the inferior retinal scans and included loss of the inner/outer segment junction band in the parafoveal region, and atrophy of the retinal pigment epithelium (Fig 1C). Only one patient showed abnormal SW-AF in the form of a central hypoAF ring surrounded by a pericentral ring of hyperAF.
Conclusions :
Rod VFs in the central macular region showed similar results to 10-2 automated VFs in patients on HCQ therapy. Deficits were parafoveal and more prominent in the superior VF. The added value of rod VFs in detecting toxicity in the early stages has yet to be determined.
1. Marmor MF, et al., Ophth. 2016. 123:1386-1394. 2. Bennett LD, et al., IOVS 2019. 60:1122-1131.
Fig 1A. 10-2 probability plot compared to B. Medmont probability plot for left eye of patient with classic ring scotoma. C. Corresponding inferior (top) and foveal (bottom) horizontal OCT b-scans.
This is a 2020 ARVO Annual Meeting abstract.