Purpose:
Currently, the border of idiopathic epiretinal membranes (iERM)is outlined operatively using vital dyes.Therefore, we aimedin our study to investigate the role of the preoperative retinalthickness map (RTM) of the optical coherence tomography (OCT)in identifying the shape and the size of the iERMs.
Methods:
15 eyes of 15 patients with iERM who underwent vitrectomy withindocyanine green (ICG)-assisted membrane peeling, were includedin this study.Each operative photo had to be well edited tofit exactly its corresponding enface image, which in turn representsthe definitive position and size of the corresponding RTM (Fig.1).We analyzed the operative images and preoperative Cirrus HD-OCTto detect the shape and the size of the iERM as well as theshape and the size of each thickness-indicating color (white,red, orange and yellow) on the RTM, respectively. The correlationof areas and morphologic characteristics between both groupswas explored.
Results:
IERM morphologic characteristics: a similarity between the iERMcontour and the corresponding RTM was found in 13 cases (86.6%).Furthermore, retinal folds were found in 6 iERMs and in theircorresponding RTMs.IERM size: there was positive correlationbetween the iERM area and each studied colored area in RTM (Fig.2).The most significant correlation was between iERM and the redarea (440-480 µm) (r: 0.87; p < 0.0001).
Conclusions:
The red area in preoperative RTM, which represents the 440-480µm retinal thickness, can be a good predictor of the extentand the shape of the iERM. iERM-related retinal folds are clearlydistinguishable on the HD-OCT.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • macula/fovea