Diameter of cystoid spaces and choroidal hypertransmission as novel prognostic biomarkers in myopic foveoschisis

Purpose: To analyse optical coherence tomography (OCT) biomarkers of anatomical and functional success in myopic foveoschisis (MF) (stage I and II of ATN classification) undergoing pars plana vitrectomy (PPV). Materials and methods: Isolated MF cases who underwent PPV showing preoperative optical coherence tomography (OCT)-documented integrity of the foveal ellipsoid zone (EZ) and retinal pigmented epithelium (RPE) were included. Availability of good quality preoperative and 1-year-postoperative OCT acquisitions was also mandatory for inclusion. Anatomical success was defined as persistence of <20% of preoperative cystoid spaces within the parafoveal region and preservation of the foveal EZ and RPE. Functional success was defined as postoperative improvement of at least 10 ETDRS letters. Results: Anatomical success was obtained in 86.1% cases (31/36). A significantly higher prevalence of preoperative choroidal hypertransmission (CH) with preserved EZ and RPE was detected in the anatomical failure group. Functional success was reported in 72.2% of cases. A larger diameter of preoperative foveal cysts and the presence of a cotton ball sign were associated with a worse functional outcome. Dome shaped macula (DMS) was associated to a good anatomical and functional outcome. Conclusions: Our retrospective analysis highlighted that the preoperative presence of a foveal CH with preserved foveal EZ and RPE might be predictive a postoperative anatomical and functional failure in MF surgery. By contrast, a larger diameter of foveal cysts might be associated to functional failure despite anatomical success, while DMS might be a predictor of good prognosis. Assessment of the described biomarkers on a larger prospective cohort is needed to validate our findings.