Surgical stimulation of the uveoscleral outflow. Experimental studies on enucleated human eyes

Six series of experiments were performed on 45 isolated cadaver eyes. In the first series, the outflow facility of the human sclera was measured, in the others, five surgical techniques for stimulating the uveo-scleral outflow were evaluted with the help of a constant pressure perfusion technique. It was found that the scleral C-value was pressure independent and its average value was equal to 0.0036 mm3/min/mmHg per 1 cm2 (100 mm2) of scleral surface. After the implantation of a scleral strip into the supra-uveal space, the mean increase in the total C-value was 23% of its initial value, ranging from 7 to 35%. After cyclodialysis the C-value increment varied from 17% to 66%, averaging 30%. The average increase in the outflow facility amounted to 60% (range 24--96%) in those cases where implantation of the scleral strip in the suprauveal space was combined with cyclodialysis. After implantation of a scleral strip, combined with subscleral sinusotomy, the C-value increment varied from 18 to 71%, averaging 41%. After cyclodialysis combined with goniospasis, the mean increase in the outflow facility coefficient was 62% (range 43%--108%).