Abstract
Purpose :
Postoperative metamorphopsia was reportedly related to deformation of the macula after macular hole surgery with the internal limiting membrane peeling. However, the mechanism is still under debate. The purpose of the present study was to investigate the correlation between postoperative metamorphopsia and macular deformation by analyzing the deformation of the grid overlaid on the fundus photograph.
Methods :
Consecutive eyes that underwent pars plana vitrectomy for idiopathic macular hole and achieved hole closure were analyzed retrospectively. The fundus photographs were taken before and at 6 months. Postoperative vertical and horizontal metamorphopsia was assessed using M-chart. Two photos were overlapped matching the major arcade vessels. The 6x6 mm grid having crossing lines at 1mm interval was overlaid on the preoperative photo. Each node was anchored at the photo, which was deformed by moving the node to match the retinal vasculatures to those of the postoperative photo (Figure 1). Differences in the coordinates of the nodes were calculated and analyzed to find correlation with M-score. Parafoveal deformation was defined as differences in coordinates between the center node and the first adjacent nodes, and perifoveal deformation as between the first and second nodes.
Results :
In 33 eyes, the average displacements of the nodes were 25.92um to the disc and 14.03um inferiorly. On the vertical lines of the grid, the average difference in X-coordinates between the adjacent nodes was 81.62 um, and on the horizontal line, the average difference in Y-coordinates was 47.01 um. Horizontal M-score was correlated with the superior perifoveal horizontal deformation of the vertical line on the fovea (p=0.013), and vertical M-score was correlated with the temporal perifoveal vertical deformation of the horizontal line on the fovea (p=0.007)
Conclusions :
Postoperative metamorphopsia after macular hole surgery was correlated with perifoveal deformation of the macula.
This abstract was presented at the 2019 ARVO Imaging in the Eye Conference, held in Vancouver, Canada, April 26-27, 2019.