Update and review of Urrets-Zavalia syndrome.

For more than half a century, Urrets-Zavalia syndrome (fixed dilated pupil) has been described as a postoperative complication of ophthalmic surgery. Since first reported as a complication of penetrating keratoplasty for keratoconus in patients receiving atropine, the characteristic features of Urrets-Zavalia syndrome have been expanded. In previous literature, a total of 110 cases resulted in a fixed and dilated pupil. Increased intraocular pressure (IOP) in the immediate postoperative period, phakia, and air or gas in the anterior chamber appear to be the most important risk factors for Urrets-Zavalia syndrome following ophthalmic procedures. Mannitol, IOP control, the removal of air or gas in the anterior chamber, and iridectomy have all demonstrated utility in managing Urrets-Zavalia syndrome.