Figure 4. Preferred retinal locus shift is maintained in the treated area after 5 years.
(a) Colour retinal photograph of the treated (left) eye of participant L1. (b) Blue-light autofluorescence image of the retina at baseline in L1. There are two retinal islands remaining, one of which (T, outlined in blue) was treated with the vector bleb (dotted line) whilst the other (U, outlined in green) remained untreated. The position of the degenerate fovea is marked as a cross. The optic disc is indicated by a circle. (c) Microperimetry fixation chart at baseline before gene therapy shows a vague preferential retinal locus (yellow dots – fixation points during testing) in the inferior macula area (white arrow). (d) The fixation shift to the region treated (T) by gene therapy (white arrow) is maintained after 5 years, with no fixation on the untreated area of retina (U) below. This was associated with an improvement in best-corrected visual acuity (BCVA) from 6/96 to 6/30 Snellen equivalent. Scale bars represent 1.0 mm.