The aim of study was to asses the influence of the type of viscoelastic substances on the level of intraocular pressure (IOP) after cataract surgery and intraocular lens (IOL) implantation. In the study group of 100 patients Viscoat was ušed at 32 operated eyes, Provise at 14 eyes and Duovisc in 54 eyes during phacoemulsification and IOL implantation. IOP was measured before surgery, one day after surgery and one week after surgery. Mean IOP level 1. day postoperatively was 24,94 mmHg in the Viscoat group of eyes, 24,65 mmHg in the Provise group and 21,09 mmHg in the Duovisc group. The type of viscoelastic substance ušed during the surgery significantly influenced the level of IOP in the first postoperative day. The level of IOP was significantly lower in the Duovisc group comparing to Viscoat and Provise. The level of IOP did not differ significantly between the Viscoat and Provise group. One week after surgery the level of IOP was not significantly different between all types of viscoelastic device. Duovisc was the most profitable viscoleastic substance in the point of view of the course of phacoemulsification, IOL implantation and postoperative level of IOP.

        Key words: viscoleastic substance, phacoemulsification, IOL implantation, intraocular pressure