Retrobulbar haemorrhage and globe perforation after botulinum toxin injection into the medial rectus

Abstract

Aims/Purpose: The aim of this communication is to show a recent case of both retrobulbar haemorrhage (RH) and probable globe perforation (GP) after botulinum toxin (BT) injection in the medial rectus of the right eye.Methods: We selected a recent case seen at our hospital. A 5u BT injection was performed under topical anaesthesia and guiding electromiography into the medial rectus due to a VI cranial nerve palsy. 2 min later the patient claimed intense pain and we evidenced a sudden growing periocular oedema and progressing exophthalmos. Retrobulbar haemorrhage was diagnosed and immediate canthotomy and cantholisys were performed, with consequent haemorrhage drainage. In the 24 h follow‐up visit, our patient claimed blurry vision and floaters. VA RE was 0.3 (before BT 0.7). Important corneal oedema and 3–4 + tyndall was observed. In the funduscopic exploration severe hemovitreous was observed; and an ocular ecography was performed, which showed no signs of retinal disruption. As vitreous started clearing and VA and floaters improved, observational treatment was decided. When we became able to see the retina with detail a possible perforation hole was seen in the infero‐medial quadrant, with no signs of traction or retinal elevation.Results: 3 months later, VA was 0.8 e° 1. Funduscopy showed an applied retina, with only a few persistent fibrine remainders in the inferior quadrant. Good‐coloured optic disc, with physiologic excavation and no signs of atrophy.Conclusions: Eventhough RH and GP are quite rare complications after BT infection, we should always take them into consideration. We also wanted to highlight these complications treatment. RH: Immediate canthotomy and cantholysis must be performed GP: close observation must be followed in order not to miss a retinal detachment. Plus, to avoid them we should be careful to perform the right technique and to use the electromiograph to guide us into the muscle.