• Retina/Vitreous

    Review of: Risk of cystoid macular edema following cataract surgery in retinitis pigmentosa: an analysis of United States claims from 2010 to 2018

    Antonio-Aguirre B, Swenor B, Canner J, et al. Ophthalmology Retina, in press

    This study sought to address broad concerns that patients with retinitis pigmentosa (RP) could have increased post-cataract surgery risk of cystoid macular edema (CME). With subsequent degradation of vision negating the surgery’s goal, the investigators quantified the risk and endeavored to pinpoint any risk factors.

    Study design

    This was a retrospective multicenter cohort study looking at patients undergoing cataract surgery between 2010 and 2018 using the IBM MarketScan claims database. The goal was to evaluate the incidence of pseudophakic cystoid macular edema (CME) in patients with underlying retinitis pigmentosa (RP) compared to patients without the disease.

    Outcomes

    A total of 615,645 eyes were included in the study, 124 of which had underlying RP. Patients with RP were 4.83 times more likely to develop postoperative CME after cataract extraction compared to the control group. Interestingly, stratified analysis demonstrated that the presence of epiretinal membrane (ERM) in patients with RP decreased the risk of CME while increasing the risk of CME in the control group.

    Limitations

    There was asymmetry in the numbers of RP vs cohort patients in the study, which sometimes is one of the weaknesses of retrospective studies. The age of the cohorts was different (mean age at the time of surgery for RP patients was 50.5 years, while the age of controls was 6.3–9.1 years older), which by itself can introduce bias into the calculation as age is one of the factors that can influence the development of pseudophakic CME.

    Clinical significance

    This study suggests that underlying RP significantly increases the risk of developing pseudophakic CME after cataract surgery. Moreover, pre-existing ERM was found to be protective against the development of pseudophakic CME. However, there was a significant difference in the age of the 2 cohorts analyzed, which may lead to bias. Further prospective data is needed to solidify this conclusion.