Toxic anterior segment syndrome (TASS) is an acute postoperative sterile inflammatory reaction that occurs 12–48 h following uneventful cataract surgery. In the past this condition was known by many names, such as postoperative uveitis and sterile endophthalmitis. Even though the expression ‘toxic anterior segment inflammation’ was used by Monson et al in 1992,1 the term TASS has only become well-known over the last 8–10 years. The characteristic clinical features are diffuse limbus to limbus corneal oedema secondary to toxic damage to corneal endothelial cells, fibrin in the anterior chamber (most often with hypopyon) due to the breakdown of the blood–aqueous barrier, secondary glaucoma due to trabecular meshwork damage, and damage to the iris resulting in an irregular or dilated pupil. Sometimes the reaction is mainly limited to corneal endothelial cell damage, when it is termed toxic endothelial cell destruction. Typically such eyes respond to intensive steroid therapy and may recover well. However in severe cases, residual sequelae such as permanent corneal oedema and glaucoma can persist.2

Any discussion on TASS raises the following questions.

1. Is it …