History and Objectives: The age of patients with cataract is usually high and their cardiovascular and pulmonary problems, proper anesthesia and control of intraorbital pressure during surgery is of great importance. Since positive Lidocaine effect on different concentration (0.25 to 4%) have been reported on intraorbital pressure. In order to study the effect of 2 and 5% doses of Lidocaine on the intraorbital pressure and start of retrobullar blockage at Kerman Medical Center in 1997.

Materials and Methods: A double blind experimental study was performed on 200 patients. Patients were divided into 2 groups (100 patients in each group) for 2% and 5% Lidocaine treatment and its effect on reduction of intraorbital pressure, commencement of anesthesia and its side effect on the eye of cataract patients were examined. Chi-square and T-test was performed.

Results: 40% of patients in 2% Lidocaine and 44% patients in the 5% Lidocaine group were female with mean age of 65±8.6 years in the first group and 63.3±7.9 years in the second group respectively. 87% and 51% reduction of intraorbital pressure was recorded in 5% and 2% Lidocaine groups respectively (P<0.001). After three minutes 90% of the 5% Lidocaine group and 5% of 2% Lidocaine group anaesthetized (P<0.001). In 2% Lidocaine group 4 patients had ocular hematoma, which was absent in 5% Lidocaine group.

Conclusion: 5% Lidocaine treatment is recommended for cataract patients.