Abstract
Purpose: :
To evaluate whether best corrected visual acuity (BCVA) and Spectral Domain Optical Coherence Tomography (SD-OCT) parameters are predictive of visual acuity (VA) outcome after pars plana vitrectomy and surgical removal of idiopathic epiretinal membranes.
Methods: :
This study included 15 eyes of 15 patients undergoing vitrectomy and membrane peeling for idiopathic epiretinal membranes in the department of Ophthalmology, University of Cologne. Baseline SDOCT parameters such as the mean foveal central subfield (FCS) and foveal center point (FCP) thickness of the neurosensory retina, the outer nuclear layer (ONL) and the inner layers of the retina were manually measured using computer-assisted grading software (3D-OCTOR). Qualitative SDOCT assessment included the integrity of the external limiting membrane (ELM) and the photoreceptor inner segment /outer segment (IS/OS) junction, the presence of intraretinal cystoid spaces as well as the contour of the fovea and the inner border of the ONL. SDOCT parameters, distance BCVA, near visual acuity as well as perception of metamorphopsia at baseline were correlated with VA, VA change and perception of metamorphopsia at long term follow-up (min. 9 months, mean 16.6 months).
Results: :
Better BCVA outcome after surgery was associated with a trend for better baseline BCVA (r=0.465, p=0.08) and absence of intraretinal cystoid spaces (p=0.08), though neither reached statistical significance. A greater increase in VA from baseline to one year follow-up was seen in eyes with lower baseline BCVA values (r=-0.469, p=0.08) and lower baseline near VA (r=-0.565, p=0.07). A statistically significant greater increase in near VA was observed in eyes with greater baseline ONL FCS thickness values (r=-0.519, p=0.02).Patients who perceived metamorphopsia one year after surgery showed significantly thicker inner retina layers at the FCP at baseline than those without (p=0.05). None of the other parameters showed predictive value in our dataset.
Conclusions: :
SDOCT allows detailed evaluation of retinal morphologic changes during follow-up in patients undergoing surgery for epiretinal membranes. Baseline VA as well as SDOCT parameters showed limited prognostic value for the functional outcome in our small dataset. A larger dataset may help to identify other relevant prognostic parameters.
Keywords: imaging/image analysis: clinical • macula/fovea • vitreoretinal surgery