Comparison of the thermal effect on clear corneal incisions during phacoemulsification with different generation machines.

Background And Objective: Older generation phacoemulsification units are widely employed where economics do not permit frequent upgrades. Thermal effects on the cornea while performing phacoemulsification with different generation machines were evaluated.

Patients And Methods: The thermal effect on the clear corneal incision during uncomplicated phacoemulsification performed by the Series 10,000 (Alcon Laboratories, Fort Worth, TX) and the Diplomax (Allergan, Irvine, CA) machines was clinically evaluated and correlated with the effective phacoemulsification time required. The clinical outcome was analyzed with respect to wound closure and surgically induced corneal astigmatism.

Results: The average effective phacoemulsification time required to emulsify a grade IV cataract was 88.33 +/- 15.81 seconds with the Series 10,000 machine and 61.67 +/- 21.79 seconds with the Diplomax machine. A grade 2 or more thermal effect was seen in 19.33% of patients operated on with the Series 10,000 machine and 3.22% of patients operated on with the Diplomax machine. The resultant tissue retraction affected wound closure and mean surgically induced corneal astigmatism (1.71 +/- 1.05 D with the Diplomax machine and 2.21 +/- 1.32 D with the Series 10,000 machine).

Conclusions: Newer generation machines require less phacoemulsification power to emulsify hard cataracts, and the clinical outcomes are more favorable. Incision burns must be kept in mind when working with older generation phacoemulsification machines.