Matthew Simunovic1 ,4, Kanmin Xue1 ,2, Jasleen Jolly1 ,2, Robert MacLaren1,2
Purpose: To study the short term effects of iatrogenic macula detachment in patients with well-preserved visual function.
Methods: Five participants aged 23-71 yr, with visual acuities from 39 to 70 letters, were recruited from a Phase I/II trial of gene therapy for choroideremia (ClinicalTrials.gov NCT01461213). Subjects underwent unilateral sub-retinal injection of 0.1mL of a solution containing 1011 AAV2.REP1 particles. Patients were assessed prior to surgery with follow-up at 1 day, 1 week and 1 month following surgery. Structure was assessed by spectral-domain OCT and function by visual acuity, microperimetry, colour discrimination (FM 100Hue) and colour matching (Rayleigh match).
Results: Sub-retinal fluid was eliminated by day 1. No evidence of change in central foveal thickness was found (change in CFT +9.6 ± 7.2 ?m in treated eyes versus +8.8 ±12.6 ?m in control eyes at 1 month). Visual acuity recovered to baseline by 1 month (change +5.4 ± 3.3 letters and +0.8 ± 3.1 letters in treated and control eyes respectively) . In one subject, pseudoprotanomaly was observed at the Rayleigh match, indicating decreased cone photopigment optical density. This finding was accompanied by a loss of tritan color discrimination at the FM100Hue and persisted at 1 month.
Conclusions: The iatrogenic macula detachment performed as part of gene therapy in this study recovered by day 1 and did not appreciably affect central foveal thickness. Whilst visual acuity and threshold sensitivity recovered by 1 month, subtle alterations in color matching – suggestive of decreased cone photopigment optical density – may persist.