To the Editor. —Chondroitin sulfate is a new viscoelastic substance that is advocated as a protective agent for intraocular lens insertion. Chondroitin sulfate has been shown to be more effective in protecting the endothelium of animal and human corneas than other substances.1Contact of intraocular lenses with endothelium causes endothelial damage and loss of cells.2Sodium hyaluronate has also been advocated to protect endothelial cells.3Sodium hyaluronic acid has been associated with postoperative increases in intraocular pressure and this is speculated to be due to an obstruction in aqueous outflow.4An advantage of chondroitin sulfate is the lack of postoperative rise in IOP.1During cases in which chondroitin sulfate was used, it was noted that blood on the operative field appeared abnormal. The blood appeared more violaceous and "clumped" in the operative field (Fig 1). This occurred on the surface of the conjunctiva and within