An unusual presentation of Urrets-Zavalia syndrome after minimally invasive glaucoma surgery in a case of pigmentary glaucoma

Urrets-Zavalia syndrome (UZS) is a rare post-operative condition characterized by a fixed and dilated pupil after ophthalmic surgery. UZS syndrome was first appreciated by Castroviejo and was later published in 1963 by Alberto Urrets-Zavalia in patients who underwent penetrating keratoplasty (PKP). Though there are many risk factors for UZS, the most widely accepted theories are ischemia of the iris and acute rise in intraocular pressure (IOP), with possible spontaneous partial recovery expected in some of them. Contrastingly, permanent UZS was also rarely reported in the literature by Mocan et al. among the pigment dispersion syndrome (PDS) population. In this manuscript, we have reported an unusual presentation of UZS after iStent implantation (Glaukos Corporation, United States) with the following two possible risk factors, namely, acute post-operative IOP spike and pre-existing pigmentary dispersion syndrome condition, which, accordingly to our knowledge, has never been reported in the literature before.