Determinants of Glaucoma Therapy Escalation After Descemet-Stripping Automated Endothelial Keratoplasty To Treat Pseudophakic Bullous Keratopathy: A Nested Case-Control Study

Purpose: To study the determinants of glaucoma therapy escalation (GTE) after Descemet-stripping automated endothelial keratoplasty (DSAEK) for pseudophakic bullous keratopathy in an eye-care hospital in Saudi Arabia. Methods: This nested case-control study evaluated patients who required medical or surgical treatment for controlling glaucoma after DSAEK (defined as GTE; GTE group). A group of patients who did not require any intervention post-DSAEK served as controls (control group). Data were collected on preoperative, intraoperative, and postoperative parameters for DSAEK. Variables were compared between groups to evaluate risk factors for GTE and graft failure. Results: The study sample comprised 117 eyes (40 in the GTE group and 77 in the control group). Glaucoma was present in 20 (17.1%) of the eyes before DSAEK. The median duration of follow-up was 27 months [Interquartile range (IQR): 24; 42]. Intraoperative complications occurred in 4 eyes, and 2 eyes had a decentered donor button. Graft failure causing vision impairment and GTE at the final follow-up were noted in 19 (16.2%) and 40 (34.2%) eyes, respectively. Glaucoma prior to DSAEK was significantly associated with GTE [odds ratio (OR) = 6.4; 95% confidence interval (CI) 2.4; 18.3; P = 0.0004]. A history of penetrating keratoplasty (PK) was significantly associated with GTE after DSAEK [OR = 6.2 (95% CI 1.5; 24.7) P = 0.008]. At the last visit, GTE and graft failure were positively associated (OR = 27.2, P < 0.005). Conclusion: Escalation of glaucoma therapy was warranted in one in 3 eyes that had undergone DSAEK. GTE and graft failure are interrelated complications. Patients with glaucoma and PK have a higher risk of GTE post-DSAEK.