Pain during second eye cataract surgery under topical anesthesia: an intraindividual study

Aim of the study was to investigate: 1) if second eye cataract surgery under topical anesthesia is more painful than surgery on the first eye, 2) if pain experienced during the procedure on the first eye may predict the pain of the second procedure, and 3) if patients' cooperation is different between the first and the second eye procedure. Seventy-three consecutive patients undergoing bilateral non-simultaneous cataract surgery were prospectively included in the study. Surgical technique was sutureless clear corneal phacoemulsification under topical anesthesia. Immediately after surgery every patient graded the pain experienced using a visual analogue scale (VAS) from 0 (no pain) to 10 (unbearable pain). At the end of each procedure the surgeon graded patients' cooperation using a 4-point scale. Mean VAS score was 2.35 (SD 2.63) for the first eye and 2.89 (SD 2.93) for the second eye. Such a difference was not statistically significant (p = 0.1777, Wilcoxon test). The correlation between the VAS score of the first and that of the second procedure was statistically significant (r = 0.5514, p < 0.0001, Spearman rank correlation). Patients' cooperation was 2.64 (SD 0.63) during the first procedure and 2.52 (SD 0.79) during the second procedure; this difference was not statistically significant (p = 0.1769, Wilcoxon matched-pairs signed-ranks test). After uneventful cataract surgery under topical anesthesia, pain experienced and cooperation did not differ between first and second eye procedures. A correlation was found between pain scores of the first and the second eye procedures.