Evaluation of macular displacement after retinal detachment using preretinal infrared imaging

Purpose: It has been previously demonstrated that retinal displacement can occur following rhegmatogenous retinal detachment (RRD). However, earlier studies have shown retinal displacement by assessing the hyperfluorescent properties of blood vessels post-surgery. To our knowledge, there is no study evaluating retinal displacement by comparing macular images before and after RRD. The purpose of this study is to quantitatively evaluate retinal displacement using pre-detachment near-infrared reflectance imaging through Python-based semi-automated software and to identify risk factors that may influence displacement. Materials and Methods: This multicenter, retrospective study included eyes with a history of macula-off RRD that underwent infrared optical coherence tomography (OCT) imaging before and after detachment surgery. The images were processed using software developed in Python. For each image, 4 vascular bifurcation points from the superior and inferior quadrants were selected, with the optic nerve head used as a reference. Retinal displacement was assessed by measuring the angular and distance changes of each retinal point relative to the optic nerve head in postoperative images, using pre-detachment images as reference. Statistical analysis was conducted to determine factors influencing retinal displacement, including lens status, tamponade type, tear location, presence of proliferative vitreoretinopathy (PVR), retinotomy, retinectomy, and detachment quadrant. Results: A total of 45 eyes were included in the study. The mean angular retinal displacement was -0.72±5.26° for Follow-up (+) and -0.94±4.31° for Follow-up (-). The mean angular displacement was calculated as -0.72±5.26°, with the absolute value of angular displacement averaging 3.87±3.57°. Retinal displacement was significantly observed in the inferior quadrant for the 4 selected moving points (p<0.05). Multivariate linear regression analysis showed that nasal quadrant tears and the presence of PVR were risk factors for increased displacement in Follow-up (+) images, while retinotomy was associated with reduced displacement (p-values: 0.035, 0.025, and 0.03, respectively). In Follow-up (-) images, nasal quadrant tears, gender, and the presence of PVR were statistically significant risk factors (p-values: 0.031, 0.018, and 0.022, respectively). Conclusion: To our knowledge, this is the first study to quantitatively demonstrate that different factors can affect retinal displacement in various retinal locations, using a program developed to evaluate pre-detachment macular images. Further studies with larger sample sizes, comparing different surgical techniques and assessing various risk factors in detail, are needed using pre-detachment retinal images. Keywords: near-infrared reflectance imaging, retinal displacement, optical coherence tomography, retinal detachment, pars plana vitrectomy