Abstract
Purpose: :
To compare rates of usage between two anti-vascular endothelial growth factor (anti-VEGF) intraocular injections, bevacizumab and ranibizumab, within the United States Veterans Administration (VA) medical centers nationwide and to determine the incidence of post-injection endophthalmitis.
Methods: :
Retrospective review of data from the national pharmacy benefits management (PBM) databank was used to identify patients in the VA system nationwide that had undergone intraocular injection of bevacizumab or ranibizumab from April 1, 2006 until September 30, 2008. Post-injection endophthalmitis cases were identified by ICD-9 code.
Results: :
Between April 1, 2006 and September 30, 2008, 3126 intraocular injections of bevacizumab and 2362 injections of ranibizumab were performed in the VA system. Among these, there were a total of 4 cases of endophthalmitis (0.073%) within 1 month of injection. Three received bevacizumab (0.096%) and 1 received ranibizumab (0.042%). There was no statistically significant difference in the rates of endophthalmitis between the two groups by chi-square analysis.
Conclusions: :
Over the 30 month study period, intraocular bevacizumab injections were performed approximately 1.32 times more frequently than ranibizumab in the VA system. There was no significant statistical difference in post-injection endophthalmitis between the two groups. The rate of endophthalmitis in this cohort is slightly higher when compared with previously published reviews (0.019%-0.029%). However, these endophthalmitis rates were determined by ICD-9 code and not confirmed to be infectious endophthalmitis. The authors recognize that this is a retrospective review and patterns of practice continue to evolve. Also, given endophthalmitis is a relatively rare complication, a larger sample size will likely be required to truly delineate whether there exists a difference in post-injection endophthalmitis rates between the two agents within the VA system. We recommend continued strict adherence to pharmacy protocol and use of sterile technique to prevent this devastating complication.
Keywords: injection • endophthalmitis • vascular endothelial growth factor