Decrease of the foveal avascular zone area after internal limiting membrane peeling: single case study

PURPOSE To report a patient whose foveal avascular zone (FAZ) decreased after vitrectomy with internal limiting membrane (ILM) peeling. METHODS A 58-year-old woman underwent successful phacovitrectomy with ILM peeling for a thin epiretinal membrane in an eye with a normal foveal contour. Optical coherence tomography angiographic en face images of the 3 mm×3 mm superficial and deep inner retinal vascular plexuses were examined preoperatively, and on days 1, 2, 9, and 37 postoperatively. The changes in the FAZ areas and the thicknesses of the parafoveal retinal layers at 500 μm from the foveal center were assessed in the vertical and horizontal B-scan images. RESULTS The areas of the superficial and deep FAZ decreased after the surgery. The course of the postoperative decrease of the FAZ area in the superficial plexus can be fit by a hyperbolic curve (R2=0.993). An increase in the thicknesses of the retinal nerve fiber layer, ganglion cell-inner plexiform layer, and inner nuclear layer was observed at all times postoperatively. CONCLUSIONS We observed one case that the FAZ area decreased and the parafoveal inner retinal thickness increased after the vitrectomy with ILM peeling. The decrease in the FAZ area suggests that a centripetal movement of the inner retinal layer is probably due to the ILM peeling.