Scleral penetrations and perforations in strabismus surgery: incidence, risk factors and sequelae.

To evaluate the incidence and identify associated risk factors and sequelae of scleral penetrations and perforations during strabismus surgery.Medical records of patients who underwent strabismus surgery at Siriraj Hospital between June 2001 and May 2006 were reviewed. Strabismus operations were performed by residents in ophthalmology training, pediatric ophthalmology fellows, or attending physicians. The authors documented demographic data, surgical techniques, and management of the scleral penetrations and perforations. All patients with scleral penetrations or perforations were examined intraoperation by indirect ophthalmoscopy and followed up for at least 6 months to determine late sequelae of this complication.Of the 1025 patients and 2195 procedures, scleral penetrations (full thickness scleral pass without retinal break) were recognized in 15 procedures (0.68%). No scleral perforation (full thickness scleral pass with retinal break) was found. The mean age of these complications during strabismus operations was 14.26 years. Scleral penetrations were more likely to occur with rectus muscle recession than rectus muscle resection. All sclera penetrations occurred while rectus muscles were recessed and reattached to the new insertions. All 15 scleral penetrations were performed by residents in training or pediatric ophthalmology fellows. Re-operation in the same extraocular muscle was not a risk factor for this complication. All patients with scleral penetrations were managed by dilated pupils and fundus examinations and the authors applied cryotherapy or indirect ophthalmoscopic laser to the retinal lesions. Retinal detachment, vitreous hemorrhage, and endophthalmitis were not found in the present study.The incidence of scleral penetrations in the present study was 0.68%. Risk factors of scleral penetrations in strabismus surgery are rectus muscle recession and surgeon factors. No serious complications such as retinal detachment or endophthalmitis were found in this study.