[Comparison of ultrasound and hydrodynamic parameters in phacoemulsification].

Unlabelled: Modern phacoemulsifiers have the widest selection of ultrasound parameters. Existing approaches to comparing the settings of the phaco machines have shortcomings and thus cannot be considered objective.

Purpose: To find a technique that would allow objective in vivo evaluation of various ultrasound and hydrodynamic parameters after performing phacoemulsification. To compare the two types of phaco settings using the proposed technique.

Material And Methods: The principle of the 'Femtocomparison' method is to have each patient undergo femtolaser pretreatment before phacoemulsification, in which the lens is divided by laser into equal parts and a corneal incision and capsulotomy are performed with the same settings. Then, during the manual part, basic ultrasound and hydrodynamic data is recorded after the removal of each quadrant of the lens. The study included 58 patients with cataracts of varying densities who underwent femtosecond laser-assisted cataract surgery. In each case, one half of the nucleus was removed using torsional ultrasound with IP technology, while the other half - using a combination of torsional and longitudinal ultrasound.

Results: The 'Femtocomparison' technique allowed objective in vivo comparison of two types of ultrasound settings. When assessing these parameters, no significant differences were found in any of the patients regardless of the density of the lens nucleus (p>0.05). In soft nuclei group (NC 1-3) CDE were significantly lower when using torsional ultrasound and IP (p<0.05). In the group with dense nuclei (NC 6+), CDE and aspiration time were significantly lower when using combination ultrasound (p<0.05).

Conclusion: The 'Femtocomparison' technique has shown that torsional ultrasound with IP technology is preferable for aspiration of soft cataracts, while combined use of torsional and longitudinal ultrasound is better when removing dense lenses.