Editor,—During the early postoperative period after glaucoma filtration surgery the sclerostomy can be blocked by haemorrhage or fibrin clot.1-4 In these cases tissue plasminogen activator (tPA) can be injected into the anterior chamber after paracentesis or subconjunctivally. It works rapidly so that within 3 hours the effect is usually apparent. This report describes a patient who had massive ocular bleeding after intraocular injection of tPA.