[I[In vivo measurements of the lumen of Schlemm's canal in chronic simple glaucoma]].

"In vivo" measurements of lumen of Schlemm's canal were performed on 38 eyes with trabeculotomy made for chronic simple glaucoma. The mean value of lumen was 542 mum, much higher than the mean values measured on cadavers and quoted in literature. Contraction due to fixation and dehydration may be the main cause of those differences.