Angle-closure glaucoma following periorbital botulinum toxin injection

摘要

Angle-closure glaucoma is characterized by a rise in intraocular pressure due to obstruction of aqueous outflow. Angle-closure glaucoma can be triggered by pupil dilatation, anatomical changes in the ciliary body and iris or movement of the iris-lens diaphragm which lead to blockage of the angle by the iris tissue. The risk is highest in predisposed subjects, who may have shorter eyeballs, larger lens, shallower anterior chambers and a narrower drainage angle. Cholinergic receptors regulate intraocular pressure with muscarinic agonists able to directly increase aqueous outflow by stimulating ciliary muscles. Drugs known to cause angle-closure glaucoma include topical mydriatics, anticholinergic drugs, adrenergic drugs, antidepressants, anticonvulsants, antihistamines, antispasmolytic drugs, antiparkinsonian agents, general anaesthesia drugs, sul-phamate derivatives and botulinum toxin.