Real-world experience on intravitreal dexamethasone implant in patients with macular edema scheduled to undergo cataract surgery

Background: Patients with pre-existing macular edema (ME) due to diabetes and retinal vein occlusions (RVO) make up a growing population receiving cataract surgery. Surgery is associated with an increased risk of worsening existing ME due to post-surgical inflammation that can be further exacerbated by pre-existing diabetic retinopathy (DR) and retinal vein occlusion. This study aimed to examine the pre-operative use of intravitreal dexamethasone (DEX) implants in patients with ME undergoing cataract surgery. Methods: A retrospective study was conducted at National Cheng Kung University Hospital in Taiwan involving 19 eyes of 16 patients with DME or ME associated with RVO. All participants received a DEX implant at baseline and underwent phacoemulsification within 3 months after its insertion. Best-corrected visual acuity (BCVA), intraocular pressure (IOP) and central subfield thickness (CST) were evaluated. Results: DEX implants reduced the CST from baseline (357.8 μm) to pre-surgery (280.8 μm). This reduction below baseline continued to month 6 post-surgery (319.4 μm). From baseline (16.15 mmHg), the mean IOP initially increased pre-surgery (17.78 mmHg) before returning to the baseline value at month 6 post-surgery (16.15 mmHg). All patients improved their BCVA from logMAR 0.943 on average at baseline to logMAR 0.532 at month 6 post-surgery. Conclusions: The results of the study suggested that patients with ME could benefit from DEX implants before cataract surgery within 3 months to achieve sufficient postoperative inflammation management and limit ME deterioration. DEX implants did not increase IOP post-surgery and was similar to baseline levels.