Toxic anterior segment syndrome and Urrets-Zavalia syndrome: Spectrum of the same entity?

Abstract

The purpose of the study was to analyze the outcomes of patients with toxic anterior segment syndrome (TASS) and Urrets-Zavalia (UZ) syndrome. The records of all patients with TASS and UZ syndrome were studied. Corrected distance visual acuity (CDVA), intraocular pressure (IOP), and the details of surgeries performed were recorded at 1 and 3 months. We studied the changes in CDVA and IOP using repeated-measure ANOVA and paired t -test, respectively. Four patients (44.4%) developed refractory UZ syndrome, and five (55.6%) patients had TASS. At the end of 3 months of follow-up, all nine patients had concentric rings of iris atrophy and corneal edema. None of the cases had hypopyon or vitritis. Peripheral anterior synechiae (PAS) with secondary glaucoma was present only in cases of UZ syndrome. Among the four cases of UZ syndrome, goniosynechialysis was performed for 2 cases and trabeculectomy for one case. Despite these interventions, IOP could not be controlled. Patients in the TASS group did not exhibit PAS formation, and IOP was normal, but corneal edema and concentric rings of iris atrophy persisted. Descemet's stripping endothelial keratoplasty was performed for all the TASS cases. There was a statistically significant drop in CDVA (P = 0.028) and an increase in IOP (P = 0.029) at 3-month postcataract surgery. TASS and UZ syndrome could result in sight-threatening complications. They may be considered diseases of the same entity as both the conditions were found in the same cluster. TASS could be considered as an abortive attack of UZ syndrome.