For the past two years I have been interested in the unaccountable variation of results in the trephine operation for glaucoma simplex. Two possible causes were studied : the first was pressure and unnecessary injury to the iris, zonule and ciliary region; the second, the amount of foreign substance that could be sequestered within the shaft of the ordinary tubular drill.
PRESSURE CONTROL
In April, 1930, I exhibited1 the first attempt to eliminate pressure on the eyeball and even substituted tension during the Elliot operation. The fundamental idea was to draw the corneoscleral button up against the cutting edge by means of a suture placed in the button after it had been marked out by the drill (fig. 1). The suture (000 or 0000 twisted) and needle (Carrell) was the same as that used in a previously described2 procedure for closing cataract wounds. The needle is inserted with