Metamorphopsia following subretinal fluid resolution in resolved cases of central serous chorioretinopathy (CSCR) are more likely in patients with prior subretinal fluid accumulation recurrences as well as ganglion cell complex (GCC) and outer nuclear layer (ONL) thinning, according to findings published in Retina. The findings support the notion that changes at the photoreceptor level are primarily responsible for metamorphopsia.
Researchers conducted a retrospective study to assess relationships between clinical characteristics and optical coherence tomography (OCT) characteristics with persistent metamorphopsia after resolution of subretinal fluid in eyes with chronic CSCR.
The study included 100 participants with “resolved” chronic CSCR, 66% of whom reported visual phenomena. Researchers performed a complete evaluation and obtained OCT scans to establish qualitative and quantitative features.
The study found that, in eyes with CSCR and metamorphopsia, both the foveal and parafoveal GCC thicknesses were thinner (P =.030 and P <.0001, respectively). Additionally, the outer plexiform layer and ONL thicknesses were thinner in the foveal region in patients who reported visual phenomena (P =.016 and P =.005, respectively). The ellipsoid zone band was more frequently discontinued in these patients, as well (P =.039).
The strongest associations with presence of metamorphopsia were with parafoveal GCC thickness (P =.004), foveal ONL thickness (P =.010), and number of previous recurrences of subretinal fluid accumulation (P =.017), as demonstrated by multivariate stepwise linear regression analysis. Researchers did not find a connection with the visual disturbance and the time interval from the last subretinal fluid resolution.
The study’s findings related to clinical and structural characteristics may be useful in guiding the optimal anatomic target in individuals with CSCR.
“Importantly, our study emphasizes the idiosyncratic relationship between ONL and
GCC thinning in ‘resolved’ chronic [CSCR] eyes with metamorphopsia. The absence of a
correlation between these two variables in [CSCR] individuals without metamorphopsia
(i.e., except in the perifoveal region) suggests the presence of a pathological
dysregulation in presence of this visual phenomenon,” the study authors report.
“We can speculate that a damage of photoreceptors in these eyes may result in a postreceptoral loss as explanation for the observed inner retinal thinning.”
Study limitations include its retrospective nature and the lack of quantification of metamorphopsia in the study cohort.
Borrelli E, Costanza B, Marco B, et al. Prevalence and morphologic biomarkers of metamorphopsia in eyes with “resolved” chronic central serous chorioretinopathy. Retina. Published online May 23, 2023. doi:10.1097/IAE.0000000000003845