Scleral perforations in strabismus surgery: incidence and role of prophylactic cryotherapy--a clinical and experimental study.

摘要

PURPOSE: To determine the incidence of scleral perforations in strabismus surgery in a tertiary centre setting in India and to evaluate the risk or benefit, if any, of prophylactic cryotherapy following experimental scleral perforations in rabbits. METHODS: Seven hundred eyes of patients that had undergone strabismus surgery (1121 procedures) were examined postoperatively by indirect ophthalmoscopy. In the experimental component, 20 rabbit eyes were perforated with a 6-0 polyglactin suture. In each rabbit, one eye acted as a control while the other eye received a 20 seconds application of prophylactic cryo at the perforation site. They were then monitored for 6 weeks before subjecting some to histopathological examination by light and electron microscopy. RESULTS: Ten scleral perforations were detected in 9 of the patients (incidence of 1.42% of the eyes and 0.89% of the strabismus procedures). In the rabbits, a chorioretinal scar was seen in all perforated eyes. A mild cryo reaction was observed in the cryoed eyes. No other sequelae were seen. Histopathologic studies showed changes consistent with the normal healing process. CONCLUSIONS: Of the human eyes screened, 1.42% showed evidence of scleral perforation following strabismus surgery. In no case were sequelae leading to visual loss observed. In the rabbits no sequelae were observed at 6 weeks of follow-up apart from a chorioretinal scar and a cryoreaction in those eyes in which cryoprophylaxis had been given. Mild cryoprophylaxis did not exert any positive or negative influence on the natural course of scleral perforation in our short-term animal study.