Material and method: Eighteen cases with late-onset capsular distension (Group 1) and twenty volunteers (group 2) were included. The intraocular pressure was measured in all cases before Nd: YAG laser capsulotomy, and at hours one and three, day two and week one after capsulotomy. Ultrasonographic biomicroscopy (UBM) was performed before and one week after the procedure.

Results: The intraocular pressure readings of group 1 were: 18.6±2.5 mmHg before YAG laser capsulotomy, 19.3±2.3 mmHg one hour after the procedure, 20.9 ±2.3 mmHg three hours after the procedure, 21.3±2.1 mmHg two days after the procedure and 15.8±3.22 mmHg one week after the procedure. The intraocular pressure readings of the control group were: 14.5±1.96 mmHg before the YAG laser capsulotomy, 15±1.9 mmHg one hour after the procedure, 15.3±1.95 mmHg three hours after the procedure, 15.7 ±1.98 mmHg two days after the procedure and 14.6±1.73 mmHg one week after the procedure. The comparison of the intraocular pressures of the groups revealed statistically signifi cant differences in the intraocular pressures before, one hour after and two days after the procedure( p=0,001, p=0,000, p=0,001). The UBM examination of the cases did not reveal any correlation between distance between the IOL and posterior capsule and the intraocular pressures.

Result: Because of the high intraocular pressure in late-onset capsular distension syndrome, Nd: YAG capsulotomy can be advised. IOP monitoring is important in these cases. Keywords : Intraocular pressure, capsular distension syndrome, ultrasonographic biomicroscopy