Late-onset toxic anterior segment syndrome presenting with predominant corneal edema after cataract surgery: a case...

To describe the clinical features, course, and management of late-onset toxic anterior segment syndrome (TASS) presenting predominantly corneal edema following uncomplicated cataract surgery.

This case series includes four patients who developed late-onset TASS after phacoemulsification during a TASS outbreak in our clinic. All patients underwent comprehensive ophthalmologic examination, including best-corrected visual acuity (BCVA), intraocular pressure (IOP) measurement, slit-lamp biomicroscopy, and anterior segment optical coherence tomography (AS-OCT). Corneal edema was graded clinically, and treatment responses were evaluated.

All patients presented between postoperative days 3 and 5 with marked visual deterioration and diffuse corneal edema extending from limbus to limbus, without significant anterior chamber reaction. Initial BCVA ranged from 0.16 to 0.4 and decreased to hand motion or counting fingers during disease progression. Central corneal thickness was markedly increased in all cases. Following appropriate treatment, corneal edema gradually resolved and visual acuity significantly improved in all patients.

Late-onset TASS may present with predominant corneal edema without significant anterior chamber reaction. Early recognition and prompt initiation of intensive corticosteroid therapy are essential for favorable visual outcomes. Clinicians should consider this entity in patients presenting with delayed postoperative corneal edema.