MICROPERIMETRY AS A SCREENING TEST FOR HYDROXYCHLOROQUINE RETINOPATHY: The Hard-Risk-1 Study.

PURPOSE: To assess the sensitivity and specificity of microperimetry as a screening test to detecting hydroxychloroquine retinopathy. METHODS: Retrospective cohort study. Patients with history of hydroxychloroquine use for more than 5 years and with concomitant microperimetry and multifocal electroretinogram testing were retrospectively reviewed. Microperimetry was considered positive if there were three or more contiguous scotoma points in the parafoveal region. Multifocal electroretinogram was used as gold standard and was considered positive if there was an increased R1/R2 ring ratio (>2.5) or reduced R1 absolute amplitude (<9.0). Sensitivity, specificity, positive predictive value, and negative predictive value of microperimetry were calculated. RESULTS: A total of 197 patients were reviewed. Hydroxychloroquine retinopathy was present in 22 (11%) patients. Their mean (SD) age was 54 (14) years, and 96% were women. Their mean (SD) daily dose was 5.7 (1.3) mg/kg, cumulative dose was 2041 (1,548) g, and duration of use was 15 (10) years. Sensitivity, specificity, positive predictive value, and negative predictive value of microperimetry were 73%, 93%, 53%, and 96%, respectively. CONCLUSION: Microperimetry has inferior sensitivity but good specificity in detecting hydroxychloroquine retinopathy (compared with multifocal electroretinogram). As such, it may be a useful ancillary test to exclude retinopathy, especially in high-risk patients or those with conflicting results on different modalities.

Progression of Retinitis Pigmentosa as Measured on Microperimetry: The PREP-1 Study.

PURPOSE: To evaluate yearly progression of retinitis pigmentosa (RP) using microperimetry (MP) performed on Nidek MP1 (NAVIS Software v1.7; Nidek Technologies, Padova, Italy). DESIGN: Retrospective longitudinal study. PARTICIPANTS: RP patients with consecutive MP tests (using the same test settings). METHODS: Data were collected as part of the Photoreceptor Cell Death in Retinitis Pigmentosa Retrospective (PREP-1) study. Visual acuity, fixation stability, mean sensitivity, and regional sensitivity were assessed at baseline and at yearly follow-up appointments. Regional sensitivity was calculated based on 2 methods. Method 1 involved topographical division into central macula (CM) and paracentral macula (PM). Method 2 involved functional division into the edge of scotoma (ES) and the seeing retina (SR). Linear mixed-effects models were used to assess the annual rate of change for each parameter, adjusted for disease duration. MAIN OUTCOME MEASURES: Annual rate of change of visual acuity, fixation stability, and retinal sensitivities (mean sensitivity and regional sensitivities using methods 1 and 2). RESULTS: In total, 75 eyes of 39 patients (median age, 56 y; males, 57%) with a follow-up period ranging from 1 to 4 years were reviewed. Visual acuity at baseline was positively correlated with all retinal sensitivity parameters, most strongly with CM sensitivity (r = 0.545, P < 0.001). There was no change in visual acuity (P = 0.075) or fixation stability (P = 0.371) per year. All retinal sensitivity parameters had a significant decline per year (P < 0.001), with a decline of 0.4 decibel (dB) for mean sensitivity, 0.6 dB for CM, 0.3 dB for PM, 1.3 dB for ES, and 1.1 dB for SR. Method 2 identified the greatest number of cases, with a significant decline in regional sensitivity. CONCLUSION: MP can detect significant changes in regional sensitivity over a 1-year period in patients with RP, even as visual acuity and fixation remain stable. An individualized approach to analyzing retinal sensitivity derived from MP may offer a useful outcome measure for future clinical trials.