ANTERIOR-CHAMBER CONTAMINATION DURING CATARACT-SURGERY WITH INTRAOCULAR-LENS IMPLANTATION

Purpose: To measure anterior chamber bacterial and fungal contaminatio n at the beginning and end of cataract surgery with intraocular lens ( IOL) implantation in a large series of patients and to determine the i nfluence of preoperative treatment and operative technique on contamin ation. Setting: Department of Ophthalmology, County Hospital of Salzbu rg, Austria. Methods: This prospective study comprised 700 consecutive patients having planned cataract extraction (511 phacoemulsification, 189 extracapsular cataract extraction [ECCE]). Thirty-four patients r equired an anterior vitrectomy; 8 myopic patients did not receive an I OL. A preoperative smear and two intraoperative (at the beginning and end of surgery) anterior chamber aspirates were obtained from each pat ient. Postoperative smears were obtained at discharge. Three preoperat ive treatments were evaluated: no lacrimal system irrigation, no topic al antibiotic (n = 282); lacrimal system irrigation with balanced sali ne solution, no topical antibiotic (n = 243); lacrimal system irrigati on, antibiotic (neomycin) eyedrops (n = 175). All patients received to pical indomethacin twice a day preoperatively. Results: Preoperative c onjunctival smears showed bacterial growth in 76.6% of eyes, with coag ulase-negative staphylococci (75%) the most common bacteria. Anterior chamber aspirates were culture positive in 14.1% at the beginning and in 13.7% at the end of surgery, with coagulase-negative staphylococci and corynebacteria the most common. Contamination rates of conjunctiva l smears taken at discharge were significantly lower (35%) than those taken preoperatively. There was no statistically significantly higher risk of anterior chamber contamination in eyes having ECCE than in tho se having phacoemulsification. Preoperative treatment did not statisti cally significantly influence intraoperative aqueous humor contaminati on rates. There were no cases of acute postoperative endophthalmitis. Conclusion: Bacteria entered the anterior chamber during cataract extr action and remained there at the end of surgery in a significant perce ntage of patients. Surgical technique, preoperative antibiotics, and p reoperative lacrimal system irrigation had no statistically significan t effect on contamination.