Abstract
Purpose :
To investigate differences in retinal structure and visual function after vitrectomy in idiopathic and uveitic epiretinal membrane (ERM).
Methods :
This retrospective, observational study included patients with unilateral ERM who underwent vitrectomy. Fundus photography and optical coherence tomography were performed preoperatively, 1 month postoperatively, and 6 months postoperatively. Eyes were divided into two groups based on the association of uveitis. The macroscopic diverging angle (MDA) between superior and inferior major vessels were calculated using digital image analysis of fundus photographs and compared pre- and postoperatively. The angle of the branching vessels from the first bifurcation point and the tortuosity of the retinal vessels between the first and second bifurcations were also measured. The changes in retinal vascular geometry were compared between the groups. The thickness of ERM, M-score, and inner-retinal irregularity index was also measured and compared.
Results :
Of 70 patients, 28 patients were uvetic ERM (uERM). The change in MDA from baseline was not significantly different between the two groups at 1 and 6 months postoperatively. The change in retinal arterial and venous branching angle from baseline was significantly different between the two groups at 6 months postoperatively (p=.006 and p<.001, respectively). There was also a significant difference in the change of retinal venous tortuosity from baseline at 6 months between the two groups (p<.001). Thickness of ERM was significantly thicker in uERM than in idiopathic ERM (iERM) (12.05 and 10.64um, respectively, p=.004). The postoperative inner-retinal irregularity index improved in both groups, but the degree of improvement was significantly greater in the iERM group than in uERM group (0.047 vs 0.022, p = .047). Improvements in M-score and inner-retinal irregularity index correlated with changes in retinal vein branching angle from baseline.
Conclusions :
The degree of improvement in topographic changes varied according to the association of uveitis. Changes in retinal topography after ERM removal are thought to be caused by differences in membrane contractility depending on the mechanism of ERM formation.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.