Analysis of biometric data for IOL power calculation after micropulse cyclophotocoagulation in two-stage glaucoma and cataract surgery

PURPOSE. To evaluate biometric parameters before and after micropulse cyclophotocoagulation (MP-CPC) used as an anti-glaucoma intervention in order to assess its feasibility within a two-stage treatment strategy for glaucoma and cataract. METHODS. Micropulse cyclophotocoagulation was performed in 46 patients (46 eyes) with moderate and advanced primary open-angle glaucoma, among them six patients had a history of previous penetrating or nonpenetrating anti-glaucoma surgery. Patients were divided into two groups according to glaucoma stage: group 1 included 20 patients (20 eyes) with moderate glaucoma, and group 2 included 26 patients (26 eyes) with advanced glaucoma. Biometric parameters – axial length (AL), anterior chamber depth (ACD), and keratometric values – were measured using a noncontact optical biometer (IOLMaster 500, Zeiss AG, Germany). Measurements were obtained preoperatively and at 2 and 4 weeks after MP-CPC to assess changes over time. RESULTS. The hypotensive effect was achieved in all cases from the first day after MP-CPC and averaged 14.0±0.48 mm Hg in group 1 and 15.1±0.59 mm Hg in group 2. Axial length measurements obtained at 2 and 4 weeks after MP-CPC showed no significant changes. Mean AL values were 23.2±1.23 mm in group 1 and 23.6±1.31 mm in group 2 (p>0.05).No tendency toward shallowing or deepening of the anterior chamber was observed. In group 1, mean ACD values were 3.03±0.22 mm at both 2 and 4 weeks. In group 2, mean ACD values were 2.98±0.36 mm at both time points. The refractive power of the steep and flat corneal meridians, as well as the axis of the steep meridian, remained unchanged in all study groups (p>0.05). CONCLUSION. MP-CPC provides a pronounced hypotensive effect while exerting minimal influence on ocular biometric parameters. The stability of biometric measurements eliminates the need for repeat biometry or revision of intraocular lens power calculations after MP-CPC, thereby improving the efficiency of surgical management in patients with concomitant glaucoma and cataract.