Axial Length Changes after Glaucoma Deep Sclerectomy Surgery

Abstract

Aims: The aim of this study is to determine the longitudinal change in the eye´s axial length (AL), produced by a non-penetrating deep sclerectomy (NPDS). Methods: 22 subjects diagnosed with glaucoma were included in the study (14 at one-month follow-up and 8 at a follow-up of at least one year), who had undergone combined glaucoma and cataract surgery. Compare with a control group of 20 eyes follow up, 14 of them for one month and 6 for one year. The relationship between changes in IOP and AL were retrospectively analyzed. The intraocular pressure (IOP) measurement was taken using contactless tonometry (Topcon CT-80). The AL and depth of the anterior chamber (ACD) was calculated using optical biometry (IOL Master, Carl-Zeiss). An assessment of the refractive status was performed through subjective refraction before and after surgery. Results: An average reduction in IOP of 10.14 ± 6.67mmHg (p<0, 05) and an average decrease in AL of 0.15±0.06mm (p<0, 05) were observed in the one month follow-up group. Similarly, the group with a follow-up of at least one year shows an average reduction in IOP of 8.50 ± 5.95 (p<0, 05) an average decrease in ALof 0.10 ± 0.09mm (p<0, 05). No Statistical differences were found between the Spherical Equivalent calculated and found after the surgery. Conclusion: After undergoing NPDS, there is a reduction in AL, which becomes more pronounced with decreasing IOP and decreasing time since the operation. This reduction in IOP observed could account for these longitudinal changes (34%). The moderate linear correlation (r>0.3, p<0.05) allows us to predict the reduction in AL according to the following formula: Reduction in AL (mm) = 0.065 + (0,006xReduction in IOP).