Rectus muscle trauma complicating sub-Tenon's local anaesthesia

Purpose To describe three cases of rectus muscle trauma in patients undergoing phacoemulsification cataract extraction and intraocular lens implantation under sub-Tenon's local anaesthesia via the inferonasal quadrant. Methods Retrospective review was carried out of 3 cases from 1080 patients who underwent phacoemulsification cataract extraction and intraocular lens implantation under sub-Tenon's local anaesthesia in our unit over a 3 year period up to April 2000. Results Two patients complained post-operatively of vertical diplopia and were shown to have restriction of elevation of the eye, which was found at surgical exploration to be due to inferior rectus muscle restriction. One patient had post-operative horizontal diplopia due restriction of abduction and exploration of the medial rectus muscle was planned. Conclusion Rectus muscle trauma is proposed as a complication of sub-Tenon's local anaesthesia and caution is advised to operators to clearly identify the sub-Tenon's space for injection of local anaesthetic.