Peter Kiraly, Tsveta Ivanova, Assad Jalil
These findings underscore the need for long-term follow-up after VN treatment to detect potential late deterioration despite early visual gains. Additionally, patients who exhibit pronounced early FST improvements may benefit from modified or extended immunosuppression to reduce the risk of CRA development.
BACKGROUND: Voretigene neparvovec (VN) improves retinal sensitivity in biallelic RPE65-associated inherited retinal dystrophy (IRD), with greater best-corrected visual acuity (BCVA) gains reported in children.
METHODS: We describe a 13-year-old male with biallelic RPE65-IRD who underwent bilateral VN treatment without subretinal foveal detachment at the Manchester Royal Eye Hospital.
RESULTS: Six weeks post-treatment, BCVA improved by four lines to 0.20 logMAR in the right eye and by three lines to 0.30 logMAR in the left eye. White full-field stimulus threshold (FST) testing showed maximal gains of -37.8 dB in the right eye and -39.1 dB in the left eye. Approximately four years later, the patient presented with marked BCVA decline (0.68 logMAR in the right eye; 0.90 logMAR in the left eye) and FST deterioration to -18.2 dB and -22.8 dB, respectively. Fundoscopy revealed chorioretinal atrophy (CRA) along the vascular arcade, and optical coherence tomography (OCT) showed foveal outer retinal atrophy with relatively preserved perifoveal layers and choroidal hyperreflective foci within the CRA. The rapid BCVA decline, foveal atrophy pattern, and presence of choroidal hyperreflective foci suggest VN-related effects or an inflammatory response as the most likely contributors to CRA development.
CONCLUSIONS: These findings underscore the need for long-term follow-up after VN treatment to detect potential late deterioration despite early visual gains. Additionally, patients who exhibit pronounced early FST improvements may benefit from modified or extended immunosuppression to reduce the risk of CRA development.