Subconjunctival antibiotics: an alternative to intracameral antibiotics for endophthalmitis prophylaxis in cataract surgery

Background: There has been an increase in the use of routine intracameral antibiotics for endophthalmitis prophylaxis in cataract surgery. However, this can be associated with serious adverse events. Previously, subconjunctival antibiotics were the preferred route but there is minimal literature directly comparing the two. Hence, the safest and most efficacious route of prophylactic antibiotic administration remains controversial. Purpose: To evaluate the efficacy and safety of subconjunctival with intracameral antibiotics for postoperative endophthalmitis (POE) prophylaxis in patients undergoing uncomplicated cataract surgery. Methods: A literature review was conducted in Cochrane and PubMed for studies that compared the efficacy of prophylactic subconjunctival and intracameral antibiotics for post-cataract endophthalmitis. Searches were not limited to English or study design. Results: Three observational studies showed that subconjunctival and intracameral antibiotics both reduced POE rates. Intracameral antibiotics demonstrated a high efficacy (OR = 0.25, 95% CI 0.13-0.46, p < 0.0001) but was also associated with increased potential complications. All studies were conducted in a sequential nature during which cataract surgery techniques and instrumentation have improved in recent years. Conclusion: In institutions with a high incidence of endophthalmitis, routine intracameral antibiotic use would be more appropriate. However, in facilities with lower rates of POE, the subconjunctival route of delivery can be an alternative due to its better safety profile.