Standard Anterior Peritomy versus a Small Posterior Incision for the Implantation of the PRESERFLO Microshunt

Abstract Purpose: This study aimed at comparing two approaches for the implantation of PRESERFLO microshunts. The standardized approach (A) is an anterior approach that necessitates performing a 6-8 mm perilimbal peritomy. The second approach (P) merely required a 3 mm incision, about 2 mm away from the limbus. Methods: 126 patients, who received PRESERFLO microshunts, were retrospectively examined. Parameters compared included intraocular pressure (IOP), surgical time, medication count and complications. The follow-up duration was 9 months. Results: The baseline IOP was 21.8±8.5 mmHg and 23.9±8.1 mmHg, in A and P, respectively (p=0.08). Surgical duration differed significantly between groups (26±0.8 vs 10±0.4 minutes for A and P, respectively; p<0.001). Postoperative IOP levels were at 10.8±5.9 mmHg in A and 10.6±4.5 mmHg in P at 30 days (p=0.62) and remained thereafter similar throughout the study (all intra-group p-values>0.08). Additionally, no significant differences were recorded between groups at any point in time. Preoperative medication count was 3.2±1.3 drops in A and 3.3±1.0 drops in P(p=0.4). Postoperative values were 0.2±0.6 in A and 0.3±0.7 in P at 9 months. Both groups exhibited similar numbers of complications and surgical revisions (p-values>0.05). Conclusion: Both techniques showed satisfactory IOP and medication count reductions as well as similar safety profiles, with the posterior incision technique being 2.6 times faster than the anterior incision approach.