Nasal versus inferior 180° selective laser trabeculoplasty: a comparative study of outcomes in primary open-angle glaucoma

Purpose To compare nasal and inferior 180° selective laser trabeculoplasty (SLT) in primary open-angle glaucoma patients regarding postoperative pressure spikes, intraocular pressure (IOP) fluctuation, and short-term efficacy. Patients and methods A total of 46 eyes (23 in each group) having open-angle glaucoma with insufficient IOP control were enrolled. Preoperative and postoperative IOP were measured by Goldmann-applanation-tonometer. 50 nonoverlapping laser pulses were applied over 180° of the angle (nasal in group 1 or inferior in group 2). IOP was measured before and 1 h after SLT. Follow-ups were scheduled at the first week, first, third, and sixth months thereafter. Results The mean pre laser IOP was 19.57±4.71 mmHg in the nasal SLT group and 20.04±4.40 mmHg in the inferior SLT group. Both groups showed significant IOP reduction, with nasal SLT decreasing to 15.04±2.39 mmHg ( P <0.001) and inferior SLT to 16.13±3.55 mmHg ( P <0.001) at 6 months. However, no statistically significant differences were observed between the two treatment approaches throughout follow-up. Conclusion Nasal and inferior SLT provide comparable IOP reductions, with nasal SLT maintaining slightly lower values. Inferior SLT poses a higher risk of postoperative IOP spikes, necessitating caution in heavily pigmented angles. Nasal SLT may offer a safer alternative with fewer complications.