Intraocular irrigating and replacement fluid.

The transparency of the rabbit cornea is regulated by an toward directed bicarbonate ion pump located in the corneal endothelium. The activity of the pump may be measured directly by measuring the electrical phenomena associated with it (current, potential, tissue resistance) or indirectly with a pachymeter or specular microscope with which one may measure fluid flows into or out of the stroma. Both methods give the same results. In human corneas we find that specular microscopy can give unreliable results (the scleral clamping phenomenon) but electrical investigations of endothelial inability are reliable and very similar in magnitude to those found in the rabbit. We have investigated the effects ov various aqeuous media on the human corneal endothelium, measuring viability with our experimental set-up, and have developed one which seems to cause no trauma to these clinically important cells.