Although a point of debate, some doctors use intracameral (IC) antibiotic prophylaxis for cataract surgery to prevent endophthalmitis, and this off-label approach has gone on for decades despite the lack of Level 1 supporting evidence. A recent study based on a 2021 ASCRS member survey found a significant rise in the number of cataract surgeons who routinely opt for this treatment (66%), and an even greater number (93%) who said they would make it part of their protocol if an approved antibiotic became commercially available.

These results are notably higher than the findings of previous polls on the subject. A 2014 survey found just 50% of doctors prescribed IC antibiotic prophylaxis treatment, while only 30% said they did so in 2007. The current survey included more than 1,200 responses.

The research team from the University of California, San Francisco and Case Western Reserve University in Ohio also found most doctors preferred moxifloxacin for treatment, while the previous two polls reported vancomycin was the most frequently used IC antibiotic. Avoidance of the latter is most likely due to its association with HORV, the rare but devastating type III hypersensitivity reaction documented in a series of 36 eyes receiving vancomycin in 2017, the authors noted.

Other key study highlights include:

  • Irrigation bottle infusion and intravitreal injection were each used by only 5% of respondents.
  • For IC antibiotics, vancomycin was prescribed by 6% of doctors in the United States compared with 52% in 2014. On the other hand, 83% of respondents prescribed moxifloxacin vs. 31% in 2014.
  • The same number of cataract surgeons used compounded moxifloxacin or the Vigamox bottle as the source.
  • Researchers noted a 12% decrease in the use of preoperative (73% from 85%) and an 11% decrease in postoperative (86% from 97%) topical antibiotic prophylaxis. Additionally, the latter was not used by 24% of surgeons injecting IC antibiotics. The doctors cited the main reasons for their decision were due to mixing/compounding risk (66%) and being unconvinced of the need (48%).
  • Of the respondents, 80% said they believed a commercially approved IC antibiotic was important, and if reasonably priced, it would increase adoption of IC prophylaxis to 93% of doctors polled.

Based on the findings, ASCRS and the US Veterans Health Administration are working to organize a multicenter, prospective, randomized clinical trial in the United States called the “TIME” (topical vs. intracameral moxifloxacin to prevent endophthalmitis) study, which would evaluate the efficacy of IC moxifloxacin in reducing the post-cataract endophthalmitis rate compared with topical moxifloxacin use alone, the authors noted.

Chang DF, Rhee DJ. Antibiotic prophylaxis of postoperative endophthalmitis following cataract surgery: results of the 2021 ASCRS member survey. J Cataract Refract Surg. July 19, 2021. [Epub ahead of print].