ESCRS study notes silicone IOL material as endophthalmitis risk factor

April 30, 2007

Results of the European Society of Cataract and Refractive Surgeons (ESCRS) multicenter clinical trial of endophthalmitis prophylaxis after cataract surgery found eyes with a silicone IOL had a statistically significant, 3- to 4-fold greater risk of infection compared with eyes with an acrylic IOL implanted. Further analyses indicate that it is the silicone material itself and not the hydrophobic nature of the material that is the risk factor, said Peter J. Barry, MD, chairman of the ESCRS study.

Results of the European Society of Cataract and Refractive Surgeons (ESCRS) multicenter clinical trial of endophthalmitis prophylaxis after cataract surgery found eyes with a silicone IOL had a statistically significant, 3- to 4-fold greater risk of infection compared with eyes with an acrylic IOL implanted. Further analyses indicate that it is the silicone material itself and not the hydrophobic nature of the material that is the risk factor, said Peter J. Barry, MD, chairman of the ESCRS study.

"The primary outcome of the ESCRS study was the overwhelming benefit of the use of intracameral cefuroxime in reducing the incidence of endophthalmitis," Dr. Barry said. "However, we also looked for other potential risk factors and were surprised to see the risk was increased in eyes receiving a silicone IOL."

After ruling out any confounding effect of implantation technique, the data from the more than 16,000 enrolled eyes were further analyzed to compare rates of endophthalmitis in eyes receiving hydrophobic silicone IOLs, hydrophobic non-silicone IOLs, and hydrophilic non-silicone IOLs. Those results showed that the hydrophobic acrylic IOLs were associated with the highest rate of endophthalmitis (0.32%). Among recipients of non-silicone hydrophilic IOLs and non-silicone hydrophobic IOLs, rates of endophthalmitis were 0.17% and 0.11%, respectively. The difference in endophthalmitis rates between the latter two groups was not statistically significant.

"The direction of these data suggests that it is not the hydrophobic or hydrophilic component of the lens that is associated with endophthalmitis and we believe they raise a question about the future of silicone IOLs," Dr. Barry concluded.