Risk Factors for the Development of Ocular Hypertension After Keratoplasty: A Systematic Review

Purpose:To identify risk factors for the development of ocular hypertension after keratoplasty.Methods:A systematic search in PubMed and Embase identified 67 relevant articles published between January 1990 and 2019. We preferentially searched for data on an intraocular pressure increase above 21 mmHg at 6 months or a threshold or time point close to that and reported whether the preoperative or intraoperative status of risk factors was defined. The results were presented in evidence tables, visualizing the direction of the association, whether univariate and/or multivariate analysis was performed, and the significance level (P < 0.05). Four researchers, blinded for the risk factors, independently assigned a level of evidence (definitely, probably, possibly, not associated). Consensus was met during group meetings.Results:From the 110 studied risk factors, pre-existing glaucoma, high preoperative IOP and combined keratoplasty with removal or exchange of an intraocular lens (IOL) were definitely associated with an increased risk. In addition, if the pre-or postoperative lens status was undefined, aphakia and pseudophakia with the IOL in the anterior or posterior chamber were also definitely associated with an increased risk when compared to phakia. Glaucoma in the contralateral eye, indication of bullous keratopathy, African American descent, preoperative treatment with cyclosporine or olopatadine 0.1%, postoperative treatment with prednisolone acetate 1%, and combined surgery in general (ie, the type of surgeries undefined in primary studies) were probably associated. Multiple other identified risk factors lack sufficient evidence and need additional investigation.Conclusions:Risk factors with a definite association can help clinicians select patients at risk and adjust their follow-up and treatment. The other factors need further investigation.