Transient central retinal artery occlusion after posterior sub-Tenon's anesthesia

Abstract

Two cases of transient central retinal artery occlusion were observed preoperatively after uneventful sub-Tenon's infusion of local anesthetic for cataract surgery and intraocular lens implantation. In these eyes, the retinal circulation reperfused spontaneously before surgery and there were no visual sequelae. A third case was observed in an eye after strabismus surgery with sub-Tenon's anesthesia. The patient was left with profound visual loss in this eye. The cause of this complication is unknown, but possible factors include mechanical pressure from the bolus of the anesthetic solution or localized vasoconstriction from the anesthetic, producing a decrease in ocular blood flow. Suggestions to avoid this problem include not inserting the cannula too posteriorly, not injecting forcibly against resistance, and using the minimum volume of anesthetic possible.

Transient retinal artery occlusion during phacoemulsification cataract surgery

“…1 The incidence of TRAO has not been evaluated in prospective longitudinal case finding studies, although it can be considered as a rare event. 1 We present the largest case series reported of TRAO following phacoemulsification under sub-Tenon's anaesthesia.…”

“…4,5 A duration of anoxia of 44 h exceeds the retina's maximal survival time, 6 although neuronal cell death may occur within 97 min. 7 TRAO of very short duration may not produce visual symptoms, 1 and further investigation will not be sought. An intermediate duration of occlusion will result in symptoms 1,3,8 despite arteriolar reperfusion proven on FFA; these patients are labelled as having suffered TRAO.…”

“…7 TRAO of very short duration may not produce visual symptoms, 1 and further investigation will not be sought. An intermediate duration of occlusion will result in symptoms 1,3,8 despite arteriolar reperfusion proven on FFA; these patients are labelled as having suffered TRAO. 1 TRAO may be easily overlooked in the post-operative period.…”

“…1 We describe three patients presenting with acute post-operative visual loss following microincision phacoemulsification cataract surgery under sub-Tenon's anaesthesia (3 ml of 2% lignocaine and 500 units of hyaluronate without adrenaline), each diagnosed with transient retinal artery occlusion (TRAO). All procedures were uncomplicated with a surgical duration of o20 min with standard infusion pressures.…”

Combined propofol sedation with sub-Tenon's lidocaine/mercaine infusion for strabismus surgery in adults

“…Several authors [38][39][40][41] reported retinal and ophthalmic artery occlusion after sub-Tenon's anaesthesia, presumably due to an elevation in ocular and orbital pressure above the mean ophthalmic artery or central retinal artery pressure. This complication may be transient 38,39 or associated with other complications, such as vertical diplopia (consistent with restriction of the inferior rectus muscles), 40 in addition to orbital haemorrhage, orbital cellulitis, and central nervous system depression, 41 Feibel and Guyton 38 suggested other possible mechanisms of retinal damage by sub-Tenon's block, such as pressure on the central retinal artery or posterior ciliary arteries, or ocular vasoconstriction, leading to a decrease in ocular blood flow and a consequent reduction in ocular pulse amplitude and pulsatile blood flow. However, none of our patients sustained serious ocular injury, except for an edematous reaction of the Tenon's capsule and conjunctiva in the injected area.…”