Long-Term Outcomes of Combined Phacoemulsification and Non-Penetrating Deep Sclerectomy versus Standalone Non-Penetrating Deep Sclerectomy

Purpose: To compare the efficacy and safety of combined phacoemulsification and non-penetrating deep sclerectomy (Phaco-NPDS) with standalone NPDS in a large glaucoma cohort with long-term follow-up. Methods: This retrospective cohort study included eyes that underwent primary NPDS with or without phacoemulsification between 2013 and 2018, with follow-up through 2023. Eyes were grouped as Phaco-NPDS, NPDS-IOL, or NPDS-Phakic. Procedure selection reflected clinical decision-making (primarily lens status/cataract, age, and visual acuity). The primary outcome was surgical success. Success was defined as postoperative IOP 5– 21 mmHg with a ≥ 20% reduction from baseline at each follow-up. Complete success required no hypotensive medications, whereas qualified success was defined with or without hypotensive medications. Success was also assessed using stricter IOP upper limits (≤ 18, ≤ 15, and ≤ 12 mmHg). Secondary outcomes included visual acuity (VA), IOP, medication use, postoperative procedures, and complications. Results: A total of 276 eyes from 242 patients were included (mean age 71.7± 14.9 years; follow-up 4.25± 2.4 years). Qualified and complete success rates (IOP 5– 21 mmHg) were 78.1% and 69.2% in Phaco-NPDS, 79.0% and 68.0% in NPDS-IOL, and 83.4% and 73.3% in NPDS-Phakic, with no significant between-group differences (qualified p=0.46; complete p=0.16). Cox regression showed better complete, but not qualified, success in young phakic eyes without cataract undergoing standalone NPDS compared with Phaco-NPDS. Postoperative mean VA, IOP, and medication use were similar across groups. GPT and needling were more common during the first postoperative year, particularly in the NPDS-IOL group (OR=1.55 and 1.70, respectively). Post-GPT iris incarceration was the most frequent complication (10.5%). Conclusion: Combining phacoemulsification with NPDS was not associated with reduced surgical success. Phaco-NPDS should be considered for patients with coexisting cataract and uncontrolled glaucoma when surgical intervention is indicated. In young phakic eyes without cataract, standalone NPDS may be considered to achieve higher complete success at stricter IOP targets. Keywords: glaucoma, non-penetrating deep sclerectomy, intra-ocular pressure, cataract, phacoemulsification