Abstract
Purpose :
To analyze the prevalence and features of chorioretinal atrophy (CA) in a large series of patients treated at the same site with subretinal injection of voretigene neparvovec-rzyl (VN) for RPE65-related inherited retinal dystrophy.
Methods :
Twenty-nine patients ranged between 6 and 62 years old were treated. Of these, 25 (41 eyes) were followed up for 6 months after surgery and were divided into 2 groups according to whether they developed CA (group 1) or not (group 2). Demographic data, best-corrected visual acuity (BCVA), fundus photographs, visual field (VF), full-field stimulus threshold (FST) and optical coherence tomography (OCT) were collected. All patients underwent the same surgical procedure, performed by the same surgeon, consisting of OCT-guided 25-gauge vitrectomy followed by manual subretinal injection of VN. Each patient received oral prednisone according to protocol.
Results :
At 6 months, 9 out of 25 patients (36%) developed CA in both eyes, categorized as: nummular (5 patients) and mixed pattern (4 patients), characterized by nummular and perifoveal atrophy. The majority of patients also developed a focal atrophy at the injection site. Demographic analysis showed that group 1 was younger than group 2 (20,5±18,5 and 30,3±19,3 years, respectively, p:0,231). At baseline, group 1 had better BCVA (p:0,012), white (p:0,040) and blue (p:0,009) FST when compared to group 2. After retrospective evaluation of the surgery, we observed no significant difference in the number of blebs between the 2 groups. Intraoperative foveal detachment (IFD) occurred in 10 eyes (58,8%) among group 1 and 4 eyes (16,7%) in group 2. However, this correlation was found questionable when analyzing both eyes of each patient and within siblings with CA, as CA development was observed independently of IFD. Group 1 showed significant improvements from baseline in terms of BCVA, VF and FST. Analysis between the two groups showed no significant differences in improvement except for blue FST (-40.6±37.4 dB and -22.7±10 dB in groups 2 and 1, respectively; p:0.028).
Conclusions :
CA occurred in one-third of our patients, who were younger and had a better baseline clinical status when compared to patients without CA. Our results confirm that CA does not interfere with clinical improvement at 6 months after VN injection. More data are needed to understand the causes of CA and its impact on visual function over time.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.