The effect of surgical preparation technique on the bacterial load of surgical needles and suture material used during strabismus surgery.

PURPOSE: To investigate the effectiveness of 3 surgical preparation techniques in decreasing bacterial contamination of needles and suture material during strabismus surgery. METHODS: Consecutive patients requiring 2-muscle strabismus surgery were randomized into 1 of 3 groups. In Group A, patients' periocular skin and bulbar conjunctivae underwent preparation with 5% povidone-iodine; the drape was placed without regard to eyebrows; and an open wire-loop lid speculum was used. Group B patients underwent the same preparation as Group A patients; however, the eyelashes and eyebrows were scrubbed with 5% povidone-iodine on cotton tip applicators, and the drape was placed to exclude the eyebrows from the surgical field. Group C patients underwent the same preparation as Group B patients; however, a bladed lid speculum was used during surgery to exclude some of the eyelashes from the surgical field. After the procedure, all needles and suture materials were sent separately for aerobic culture. The data were analyzed for differences in contamination rates between the groups. RESULTS: Of 77 patients, 24 (31.4%) had either a needle and/or suture contaminant. Groups A, B, and C had mean contamination rates of 29.6%, 34.6%, and 29.2%, respectively. There was no significant statistical variation in contamination among the 3 groups. The most common organism identified was a coagulase-negative staphylococcus strain. CONCLUSIONS: More meticulous sterile preparation of the surgical field did not result in a meaningful reduction in suture or needle contamination rates during strabismus surgery.

Corneal power measurements in fixating versus anesthetized nonfixating children using a handheld keratometer.

PURPOSE: To compare keratometry measurements on a fixating patient with readings from the same nonfixating patient intraoperatively using the Nidek KM-500 handheld keratometer. METHODS: Consecutive patients who were scheduled for strabismus or nasolacrimal surgery between 5 and 11 years of age were included in the study. Handheld keratometry was performed preoperatively on both eyes with the child fixating and intraoperatively with the child anesthetized. Three readings were taken on each eye. The steepest and flattest corneal meridians were recorded. Intraclass correlation coefficients were calculated to assess reliability, and interchangeability was assessed by the use of the Bland-Altman method. RESULTS: Included in the study were 55 eyes of 28 patients. The average fixating keratometry reading was 44.10 +/- 1.45 D for right eyes and 44.12 +/- 1.42 D for left eyes. The average nonfixating keratometry reading was 44.06 +/- 1.62 D for right eyes and 44.02 +/- 1.54 D for left eyes. The intraclass correlation coefficient for the average keratometry obtained fixating versus nonfixating was 0.96 for right eyes and 0.95 for left eyes. The Bland-Altman analysis showed fairly large limits of agreement between readings, but most readings fall within the limits of variability. The mean time to obtain the intraoperative measurements was 4.26 minutes. CONCLUSIONS: In our study the Nidek KM-500 handheld keratometer provided reliable readings when used intraoperatively on anesthetized nonfixating children and required minimal time to perform.