title: Diplopia following sub-tenon's anaesthesia: an unusual complication.
abstract: Diplopia is a rare but well recognised complication following retrobulbar and peribulbar local anaesthesia but it has not been widely reported following sub-tenon's local anaesthesia (STLA). We report on a 76-year-old woman who developed vertical diplopia after left phacoemulsification. She had received a STLA. She had left hypotropia measuring 30 prism diopters for near and distance. She was managed with occlusion but there was no improvement in her findings over 6 months. Ocular motility opinion was then sought and a presumptive diagnosis of inferior rectus fibrosis was made. She subsequently underwent a left inferior rectus recession using adjustable sutures. Postoperatively she had a residual left hypotropia measuring 8 prism dioptres and single vision. Possible causes of inferior rectus fibrosis include muscle damage during traumatic sub-tenon's block or myotoxicity due to local anaesthetic agents. This case highlights the importance of close supervision of inexperienced staff administering regional anaesthetics.
authors.affiliation: Department of Ophthalmology, Medical University of Vienna, Waehringer Gürtel 18-20, 1090, Vienna, Austria. robert.blum@meduniwien.ac.at
authors.forename: Robert A
authors.initials: RA
authors.lastname: Blum
authors.forename: Lik Thai
authors.initials: LT
authors.lastname: Lim
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Weir
mesh_terms: D000368:Aged; D000772:Anesthesia, Local / Q000009:adverse effects*; D004172:Diplopia / Q000209:etiology* / Q000601:surgery; D005260:Female; D005355:Fibrosis; D006801:Humans; D019654:Lens Implantation, Intraocular; D008012:Lidocaine / Q000009:adverse effects*; D009801:Oculomotor Muscles / Q000473:pathology / Q000601:surgery; D013508:Ophthalmologic Surgical Procedures; D018918:Phacoemulsification; D013536:Suture Techniques; D058475:Tenon Capsule; D014794:Visual Fields
chemical_list: D008012:Lidocaine