Clinical Features, Prognosis, and Long-Term Response to Ranibizumab of Macular CNVs in Pattern Dystrophies Spectrum: A Pilot Study

Abstract

Introduction. To analyze the morphological and functional features of choroidal neovascularizations (CNVs) in eyes affected by pattern dystrophies (PD), evaluating their long-term response to intravitreal ranibizumab, and comparing them with CNVs in age-related macular degeneration (AMD). The mean goal is to identify possible disease biomarkers and to evaluate the long-term prognosis of CNVs in PD. Materials and Methods. A retrospective study of 42 patients with naïve CNV (26 PD and 16 AMD), for a total of 47 eyes (29 eyes in the PD group and 18 eyes in the AMD group). Each patient received a loading dose of ranibizumab (one monthly for three months) followed by pro re nata (PRN) reinjection protocol for a period of at least three years. Morphological OCT parameters (CRT, central retinal thickness; SRF, subretinal fluid; IRF, intraretinal fluid; SHRM, subretinal hyperreflective material; HRF, hyperreflective foci; HCD, hyperreflective crystalline deposits; cCT, central choroidal thickness; slCT, sublesional choroidal thickness; EZd, ellipsoid zone disruption; and best corrected visual acuity (BCVA in logMAR scale)) were reported at baseline and last follow-up. Results. At baseline, no significant differences were found between the two groups, except for choroidal thickness parameters that were significantly greater in the PD group ( p = 0.009). Longitudinal PD analysis demonstrated reduction in BCVA ( p = 0.009), decrease in CRT ( p = 0.046), resolution of SRF in 61.6% of cases ( p = 0.004) and SHRM in 30% ( p = 0.034), and choroidal thinning both centrally ( p = 0.004) and sublesional ( p = 0.011) compared to baseline. At 3 years, the PD group received significantly more injections than the AMD ( p = 0.011) and showed significantly thicker choroid ( p = 0.033) and more frequent HRF ( p = 0.006). Regarding the PD group, we found a negative correlation between age and choroidal thicknesses at baseline and at 3 years ( p < 0.05); significant positive correlations were found between baseline BCVA and at 3 years ( p < 0.001), BCVA at 3 years and IRF ( p = 0.003) and SHRM at 3 years ( p = 0.003); CRT baseline and CRT 3 years ( p = 0.017); HCD at 3 years was associated with greater CRT ( p = 0.04) and IRF at 3 years ( p = 0.019). Conclusions. Early and long-term morphofunctional features of CNVs in PD and in AMD are overlapping. CNVs in PD have poorer long-term response to ranibizumab and higher choroidal thickness suggesting different pathogenetic and evolutionary mechanisms.

Choroidal neovascularization associated with butterfly-shaped pattern dystrophy - a case report

“…Initially, it was hypothesized that the metabolic byproducts may accumulate after the RPE digests the mutant PRPH2 proteins, which may disrupt the extracellular matrix that helps maintain the barrier against CNV [ 14 ]. However, Casilo et al [ 15 ] revealed that the PD subgroup showed thicker choroidal thickness both centrally and underneath the neovascular lesion in contradistinction to the AMD subgroup. Presumably, the thickening of the outer retinal vessels in the Haller layer could cause secondary damage to the overlying choriocapillaris network and induce ischemic phenomena responsible for neovascularization.…”

“…However, in the pilot study performed by Casillo et al [ 15 ], a comparison between the long-term response to intravitreal ranibizumab among patients with PD-associated CNV and CNV in AMD, showed that eyes with PD had a poorer long-term response and greater tendency to atrophic evolution of the disease. Therefore, it is suggested that CNV associated with PD should not be “overtreated” to avoid further atrophic effects.…”