EyeWorld Asia-Pacific September 2016 Issue

September 2016 EWAP FEATURE 13 potential mechanism. Considering that vancomycin was the only surgical adjuvant in common used in all 36 eyes of 22 patients in our current series, the conclusion was that this is the most likely culprit. The timing of HORV is consistent with a type III hypersensitivity similar to leukocytoclastic vasculitis, a potentially analogous reaction in the skin that has been seen rarely with systemic vancomycin. In addition, type III hypersensitivity reactions start in the venous system, which would be consistent with the appearance of HORV, which appears to affect retinal venules more than the arterioles. Based on the cases collected to date, the Task Force Clinical Alert outlined the clinical pattern and findings with HORV. Recommendations for treatment and management were given. Without knowing the number of eyes that have received vancomycin, and without routine dilated retinal examination following uncomplicated cataract surgery, it is impossible to determine the prevalence of HORV. Our 2014 ASCRS member survey found that 50% of respondents were using intracameral antibiotics. 3 Among those using an intracameral antibiotic, vancomycin was used by 37% overall and 52% of American surgeons. We therefore think that severe HORV is extremely rare. However, some cases of HORV may also be missed or misdiagnosed— particularly if there are milder cases causing peripheral vasculitis that do not affect vision. Such milder cases of HORV would have only been discovered with a dilated postoperative fundus examination. It is also possible that prior cases of presumed endophthalmitis (cases without hypopyon and retinal findings that were out of proportion to anterior chamber and vitreous inflammation) were actually cases of HORV. Since the 2015 HORV paper was published, a number of retina specialists have come forward with cases that were previously undiagnosed but now seem to represent HORV. Now that a registry has been established and with greater awareness of the syndrome, we hope to gain a better understanding of the frequency of HORV moving forward. Because HORV is probably rare, the Task Force is not recommending that surgeons discontinue using intraocular vancomycin prophylaxis at this time. Although the ASCRS survey reflects that there is no consensus on the necessity of intracameral antibiotic prophylaxis or which agent is best, the popularity of intraocular vancomycin prophylaxis is likely based on several factors, including safety, availability, coverage, and efficacy against drug resistant pathogens. 4 Surgeons should continue to weigh the relative merits of prophylactic intraocular vancomycin use in preventing endophthalmitis, with the additional knowledge that intraocular vancomycin is likely associated with HORV, a distinctly rare and potentially devastating disease. In addition, surgeons using vancomycin prophylaxis with sequential cataract surgery should be aware that in addition to delayed onset of 1–3 weeks, HORV may be asymptomatic in the first eye and a dilated fundus exam may be the only way to detect it. Although there is no FDA approved commercial antibiotic formulation for intracameral use, compounding pharmacies can formulate intracameral cefuroxime and moxifloxacin if an alternative is desired. The ASCRS Cataract Clinical Committee published a white paper reviewing the different antibiotic options for intracameral prophylaxis in 2014. 4 If you experience or become aware of a case of HORV, please be sure that it is reported on the HORV registry, which can be accessed through links at www. asrs.org and www.ascrs.org. The identity of the patient and attending ophthalmologists will be kept strictly confidential. EWAP References 1. Nicholson LB, Kim BT, Jardon J, et al. Severe bilateral ischemic retinal vasculitis following cataract surgery. Ophthalmic Surg Lasers Imaging Retina . 2014;45:338–342. 2. Witkin AJ, Shah AR, Engstrom RE, Kron- Gray MM, et al. Postoperative hemorrhagic occlusive retinal vasculitis: Expanding the clinical spectrum and possible association with vancomycin. Ophthalmology . 2015;122:1438-1451. 3. Chang DF, Braga-Mele R, Henderson BA, Mamalis N, et al. Antibiotic prophylaxis of postoperative endophthalmitis after cata- ract surgery: Results of the 2014 ASCRS member survey. J Cataract Refract Surg. 2015;41:1300–1305. 4. Braga-Mele R, Chang DF, Henderson BA, Mamalis N, et al. Intracameral antibiotics: Safety, efficacy, and preparation. J Cataract Refract Surg. 2014;40:2134–2142. Contact information Chang : dceye@earthlink.net Witkin : ajwitkin@gmail.com