Purchase this article with an account.
S. Pasadhika, G. A. Fishman, M. Shahidi; Effects of Chronic Exposure to Hydroxychloroquine or Chloroquine on Inner Retinal Structures. Invest. Ophthalmol. Vis. Sci. 2009;50(13):5001.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness and macular inner and outer retinal thickness using spectral-domain optical coherence tomography (Sd-OCT) in patients with chronic exposure to hydroxychloroquine (HCQ) or chloroquine (CQ)
Subjects were divided into 3 groups:Group I, 8 eyes of 4 patients who had a diagnosis of either HCQ (N=3) or CQ (N=1) toxicity with abnormal fundus lesions; Group II, 16 eyes of 8 patients who had chronic exposure to HCQ without fundus changes; and Group III, 16 eyes of 8 visually-normal subjects who served as age-similar and race-matched controls for Group II. Peripapillary RNFL thickness was measured using Sd-OCT in 16 segments from 4 quadrants. The analyses were based on age- and disc size-adjusted normative data. An abnormal thinning for an individual quadrant was based on RNFL thickness measurements of less than the 5th percentile from at least 2 out of 4 segments in the quadrant. Macular scans on Groups I and II were performed to compare the thickness of the inner, outer and full-thickness retina to that of Group III.
All participants were female. The mean ages in Groups I, II and III were 57.6+8.0, 54.9+11.0 and 53.7+10.5 years, respectively (p=0.83). Duration of exposure ranged from 5-12 years (median, 7.5 years) in Group I, and from 6-35 years (median, 10 years) in Group II. Seven (88%) of 8 eyes in Group I showed peripapillary RNFL thinning in at least 1 quadrant using our criteria, while none of those in Groups II and III did so. Using macular scans, Group I showed significant thinning of the inner, outer and full-thickness retina compared to Group III (p<0.001). Group II had significant thinning only of the inner retina (RNFL+ ganglion cell layer+ inner plexiform layer) compared to Group III (p<0.001). There were no significant differences in the outer and full-thickness retinal measurements between Groups II and III (p-value of 0.98 and 0.08, respectively).
Peripapillary RNFL thinning was consistently observed in our patients who presented with retinal lesions compatible with HCQ or CQ toxicity. In contrast, we were unable to demonstrate such thinning in patients who had chronic drug exposure without fundus changes. However, using OCT macular scans, selective thinning of the inner retina was detected in the absence of clinically-apparent fundus changes. The results are compatible with previous animal studies which showed that retinal ganglion cells were affected initially with the use of CQ. Longitudinal monitoring of inner retinal structures with OCT could provide a sensitive means for detecting initial stages of drug toxicity.
This PDF is available to Subscribers Only