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Abstract

Our study used administrative data to estimate the rate of acute suspected endophthalmitis in Ontario, Canada. From over 440 000 consecutive cataract cases between 2002 and 2006, we found a rate of 1.4 per 1000.1Hatch W.V. Cernat G. Wong D. et al.Risk factors for acute endophthalmitis after cataract surgery: a population-based study.Ophthalmology. 2009; 116: 425-430Abstract Full Text Full Text PDF PubMed Scopus (111) Google Scholar Excluding cases that were in combination with any eye procedure other than anterior vitrectomy on the same day reduced the rate to 1.18 per 1000. In comparison, Lundstrom et al2Lundstrom M. Wejde G. Stenevi U. et al.Endophthalmitis after cataract surgery: a nationwide prospective study evaluating incidence in relation to incision type and location.Ophthalmology. 2007; 114: 866-870Abstract Full Text Full Text PDF PubMed Scopus (242) Google Scholar found a rate of 0.48 per 1000 between 2002 and 2004 in their sample of over 225 000 cases in Sweden. Dr. Anijeet suggests that the difference in rates between the 2 studies may be due to the use of intracameral antibiotics in Sweden. One of the limitations of using administrative data is that it cannot provide information about risk factors requiring clinical information such as the use of antibiotics. Since we were unable to evaluate the use of intracameral antibiotics in our sample, we cannot comment on whether they are protective against endophthalmitis. A Canada-wide survey in 2004–2005 reported some use of intracameral antibiotics,3Hammoudi D.S. Abdolell M. Wong D.T. Patterns of perioperative prophylaxis for cataract surgery in Canada.Can J Ophthalmol. 2007; 42: 681-688Abstract Full Text PDF PubMed Google Scholar and a high-volume cataract surgical centre in Ontario recently reported 6 cases of endophthalmitis out of 13 931 procedures (0.43 per 1000) with no use of intracameral antibiotics.4Lloyd J. Braga-Mele R. Incidence of postoperative endophthalmitis in a high-volume cataract surgicentre in Canada.Can J Ophthalmol. 2009; 44: 288-292Abstract Full Text PDF PubMed Scopus (28) Google Scholar There are many differences between the Swedish study and our study which could account for the difference in endophthalmitis rates. These include study methodology (including the definitions of endophthalmitis), case mix,5Bell C.M. Hatch W.V. Fischer H.D. et al.Association between tamsulosin and serious ophthalmic adverse events in older men following cataract surgery.JAMA. 2009; 301: 1991-1996Crossref PubMed Scopus (96) Google Scholar surgical technique (including the use of intracameral antibiotics) and surgeon volume.6Bell C.M. Hatch W.V. Cernat G. Urbach D.R. Surgeon volumes and selected patient outcomes in cataract surgery: a population-based analysis.Ophthalmology. 2007; 114: 405-410Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar Unfortunately, it is not possible to adjust for these potential confounders in a comparative analysis. Endophthalmitis after Cataract SurgeryOphthalmologyVol. 117Issue 4PreviewHatch et al1 with their large population-based study has indeed produced several benchmark statistics in the context of prevention of endophthalmitis after cataract surgery. The incidence of endophthalmitis in their cohort was 1.4 per 1000. This was compared with that of Lundstorm et al2 who reported an incidence of 0.5 per 1000 in a cohort of over 225 000 cataract surgeries over a similar period. Hatch et al1 attribute this lower incidence to study methodology, case mix, surgical technique, surgeon volume, and the definition of endophthalmitis. Full-Text PDF