Toxic Anterior Segment Syndrome Cluster After Cataract Surgery: Pattern Recognition, Source Identification Through Chemical Residue Analysis, And Successful Outbreak Prevention

To report a cluster of three toxic anterior segment syndrome (TASS) cases occurring within a single operative week following uncomplicated phacoemulsification, and to demonstrate how early pattern recognition, systematic source investigation, and immediate institutional response prevented further cases. This series emphasizes the clinical decision-making process distinguishing TASS from infectious endophthalmitis in a cluster setting, identifies residual enzymatic detergent on reusable cannulas as the common causative agent through chemical residue analysis, and documents favorable visual outcomes achieved in all three cases through early aggressive topical corticosteroid therapy without intravitreal injection.

Department of Ophthalmology, Recep Tayyip Erdogan University Training and Research Hospital, a tertiary referral center in Rize, Turkey.

Three patients (ages 65, 71, 68; 2F/1M) developed acute anterior segment inflammation 18-36 hours after uneventful phacoemulsification with posterior chamber IOL implantation on consecutive operative days by different surgeons using shared reusable instrumentation. Case 1: A 65-year-old female presented at 18h with VA of hand motions, dense fibrin, limbus-to-limbus corneal edema, fixed pupil, and IOP 42 mmHg. B-scan showed no vitritis. Case 2: Presented at 24h with similar findings (VA counting fingers, fibrin, corneal edema, IOP 36 mmHg, no vitritis), triggering TASS cluster suspicion. Case 3: Identified at 36h with comparable presentation (VA counting fingers, fibrin, IOP 34 mmHg, no vitritis). All three shared pathognomonic features: early onset, limbus-to-limbus edema, dense fibrin without hypopyon or vitritis, and minimal lid edema. All received intensive topical prednisolone acetate 1% hourly and IOP-lowering therapy without intravitreal injection. Systematic investigation included cultures of BSS, OVD lots, and instrument swabs; all bacterial cultures were negative. Chemical residue analysis identified enzymatic detergent on reusable cannulas from a malfunctioning ultrasonic cleaner rinse cycle. Surgical lists were immediately suspended, single-use cannulas adopted, cleaning protocols revised with validated rinse verification, and staff retrained. No further TASS cases occurred.

All three patients achieved complete fibrin resolution within 48-72 hours. Final BCVA at 6 months was 20/25, 20/30, and 20/25 with clear corneas and quiet eyes. This cluster series demonstrates critical lessons: (1) when multiple TASS cases share temporal proximity and identical patterns, cluster investigation must be initiated immediately; (2) the TASS triad of early onset, limbus-to-limbus edema, and fibrin without vitritis reliably differentiates from endophthalmitis; (3) topical steroids without intravitreal injection achieved excellent outcomes in all cases; (4) negative cultures with positive chemical residue analysis confirm toxic etiology; (5) immediate surgical list suspension and protocol revision prevented additional cases.