Changes in PAX7 Positive Satellite Cells in Extraocular Muscle After Strabismus Surgery

Purpose To investigate the effects of recession or re-section surgery on PAX 7 positive satellite cells of the extraocular muscle (EOM) in rabbits. Methods A total of 20 rabbits (40 eyes) were included in this study. The superior rectus muscle of the right eye was either recessed or resected. Recession surgeries were performed at a distance of 5 mm (5 rabbits) and 10 mm (5 rabbits) from the original insertion, whereas resection surgeries were performed at a distance of 4 mm (5 rabbits) and 8 mm (5 rabbits). The superior rectus (operated muscle), inferior rectus (antagonist muscle), and superior rectus of the contralateral eye (control) were extracted 4 weeks after surgery. The number of PAX7 positive satellite cells was analyzed using immunohistochemistry. Results The number of PAX7 positive satellite cells in the operated and antagonist muscles was higher than that in the control muscle after all surgeries ( P < .05, all). The number of PAX7 positive satellite cells in the operated and antagonist muscles after resection surgery was higher than that after recession surgery ( P < .05, all). Howerver, there were no significant differences of PAX7 positive satellite cells in the operated and antagonist muscles in recession and resection surgery according to the surgical amount ( P > .05, all). Conclusions PAX7 positive satellite cells in the operated and antagonist muscles showed an increase after resection surgery compared to recession surgery. This suggests that the extent of EOM regeneration may vary depending on the surgical method used for strabismus surgery. [ J Pediatr Ophthalmol Strabismus . 2025;62(3):190–195.]