Bacterial contamination of the anterior chamber during phacoemulsification cataract surgery

Abstract

The bacterial contamination rate of the anterior chamber after phacoemulsification and IOL implantation was extremely low. Additional findings support the conjunctiva as being a primary source of bacteria causing postoperative endophthalmitis as well as the ability of povidone-iodine to reduce the conjunctival bacterial load.

Survival of bacteria on the ocular surface following double application of povidone-iodine before cataract surgery

“…The reduction in bacterial load (postoperatively compared to preoperatively) was significant (Po0.001). 3 In a study of 30 patients undergoing ophthalmic surgery, there was a statistically significant decrease in the number of colonies and species in eyes receiving povidone-iodine (P-values of o0.05 and o0.01 for colonies and species, respectively), contrary to untreated eyes (not statistically significant). 7 A systematic literature review of prophylactic methods against bacterial endophthalmitis by Ciulla, Starr, and Masket gave different interventions an evidence rating (based on 88 peer-reviewed papers from 1966 to 2000) and hence a clinical recommendation.…”

“…9 Despite this, endophthalmitis is a rare complication of intraocular surgery, with an estimated incidence of 0.07-0.13% following cataract surgery. 3 A 10-year retrospective study of acute-onset (within 6 weeks of Column total 6 46 52 Column total 6 46 52 P-value ¼ 0.027. intraocular surgery) endophthalmitis at one institution elicited an overall incidence of 0.093% following intraocular surgical procedures. 10 Povidone-iodine is cheap, has a broad spectrum of microbicidal effects, and has either no or negligible toxicity.…”

“…1 The primary source of microorganisms causing postoperative bacterial endophthalmitis appears to be the eyelid margin and in turn the conjunctiva. 3 A prospective study of the incidence of bacterial contamination of the anterior chamber after phacoemulsification cataract surgery utilized two applications of povidone-iodine (10%) preoperatively. The reduction in bacterial load (postoperatively compared to preoperatively) was significant (Po0.001).…”

“…Neisseriae, Gram-negative bacilli (often Moraxella species), Propionibacterium acnes, viridans streptococci, S. aureus, and fungi may also be present. [1][2][3] Povidone-iodine has a broad spectrum of microbicidal effects 4 against various bacteria, as well as fungi, protozoa, and viruses. 5 Polyvinylpyrrolidone has a high affinity for cell membranes and delivers free iodine (I 2 ) to the bacterial cell surface.…”

“…5,6 Preoperative application of povidone-iodine to the conjunctiva and periocular skin is an effective surgical preparation technique as it is a proven method of endophthalmitis prophylaxis by reducing the number of organisms present. 7,8 As the primary source of microorganisms causing endophthalmitis is the conjunctiva, 3 the effect of povidone-iodine on conjunctival bacterial contamination may have an important influence on potential prophylaxis against endophthalmitis. It was therefore the purpose of this study to assess the incidence of positive preoperative conjunctival cultures following two applications (at the time of periorbital anaesthetic block and in the theatre approximately 10 min later) in comparison with one (at the time of anaesthetic block only) application of 5% povidone-iodine solution to the operative eye.…”