Management of Posterior Synechiae Causing Small Pupil
Small pupil may be encountered with posterior adhesions (synechiae) between the iris and the crystalline lens. As isolated pathology, it is usually a result of long-term use of miotics, pseudoexfoliative syndrome, or neurological disorders. Posterior synechiae is a result of uveitis, acute angle closure glaucoma, ocular trauma, or previous surgery. Removal of a cataract through such a pupil is challenging. The situation is recognized preoperatively by failure to achieve dilation after instillation of mydriatics such as cyclopentholate 1%, tropicamide 0.5%, and phenylephrine 10%. Posterior synechiae may be released before surgery following subconjunctival injection of Mydricaine. Patients using miotics are advised to discontinue them 3 weeks before surgery.