Retinal changes after macular translocation with 360-degree retinotomy in monkey eyes

Purpose To determine the morphologic and functional changes of the fovea and retina of monkey eyes after macular translocation with 360-degree retinotomy. Design Experimental study. Methods The retinas of eight monkey eyes were surgically translocated with a 360-degree retinotomy with procedures similar to those used on human eyes. At 1, 2, and 3 months after the surgery, the six eyes that had successful surgery were studied by light and transmission electron microscopy, terminal deoxynucleotidyl transferase (TdT)-dNTP terminal nick-end labeling (TUNEL) assay, and immunohistochemistry with peanut agglutinin (PNA) lectin and glial fibrillary acidic protein (GFAP). Retinal physiology was assessed by scotopic and photopic electroretinograms (ERGs). Results The fovea was successfully translocated approximately 30 to 40 degrees superiorly in six eyes. The translocated macula and fovea had a normal layered architecture with no TUNEL-positive cells, minimal misalignment of the outer segments, and strong immunoreactivity to GFAP. The mean amplitudes of the scotopic and photopic b-waves were significantly reduced at 1 month after the surgery, and there was only a slight recovery at 3 months. No significant changes were observed in the mean implicit times after the surgery. Conclusion These findings indicate that macular translocation surgery with 360-degree retinotomy results in minimal morphologic alterations but significant depression of electrophysiologic function.