Two consecutive clusters of toxic anterior segment syndrome

To present clinical findings and etiologic investigation of two consecutive clusters of toxic anterior segment syndrome (TASS) after uncomplicated phacoemulsification cataract surgery.

At the Veterans Affairs Northern Indiana Health Care System Fort Wayne campus, 11 consecutive patients on two separate days in 2011 underwent clear corneal incision phacoemulsification cataract surgery by the same surgeon. On the first postoperative day, all patients had 1+ to 2+ diffuse limbus to limbus stromal edema and 2+ to 4+ anterior chamber white blood cells. Five eyes had inflammatory plaques on the surface of the intraocular implant, six had fibrin, three had hypopyon, and one had inflammatory debris "puff ball." Visual acuity ranged 20/70 to 20/400. Treatment included moxifloxacin four times a day, diclofenac four times a day, and prednisolone acetate 1% every 1 to 2 hours. In all patients, active inflammation and corneal edema resolved within 6 weeks, and visual outcome was 20/20. Cataract surgery was paused for 5 months after the first cluster of TASS and then immediately paused again after restarting because of a second cluster. Although no specific causes were identified, etiologic investigation resulted in the implementation of multiple changes. The changes included new replacement surgical instruments, disposable irrigation/aspirator tip and handle, risk of residue on reusable instruments minimized, preservative-free medications used when available, ophthalmic ointment eliminated, manufacturers' recommendations followed exactly, and eye instruments processed separately. Toxic anterior segment syndrome did not occur when surgery resumed 11 months after the last cluster.

There are multiple possible etiologies of TASS. However, as in our clusters, specific causes are often not identified. Thorough review of all steps in surgery, processing of equipment and preparation of injectable solutions and materials, and adoption of best practices can prevent additional cases of TASS. Prompt diagnosis and treatment of TASS are extremely important because this leads to a desirable outcome.