Nd:YAG laser goniopuncture as a mandatory adjuvant procedure after non-penetrating deep sclerectomy (long-term observation results)

Abstract

To evaluate the effect of Nd:YAG laser goniopuncture on the long-term hypotensive effectiveness of non-penetrating deep sclerectomy. The study included 114 patients after non-penetrating deep sclerectomy (NPDS). In the control group (n=58), Nd:YAG laser goniopuncture was performed within 3.4±1.9 (1.5-6.7) months, and in the main group (n=56) - within 1.12±0.08 (0.9-1.5) months after the surgery. Ultrasound biomicroscopy (UBM) was used to evaluate the semiotics of trabecular-Descemet's membrane (TDM), intrascleral canal (ISC) and filtering bleb. The follow-up period was 5 years. According to UBM data, the thickness (0.10±0.009 mm) and density (50±6%) of TDM (p=0.0001) increased before LGP in the control group, the height of ISC decreased to 0.49±0.19 (0.20-0.40) (p=0.03), the height of UBM scan - to 1.49±0.05 (1.41-2.9) (p=0.0001); IOP (P0) was 18.48±4.7 (11.2-22.9) mmHg (p=0.001). In the main group before LGP, TDM thickness was 0.08±0.006 mm, density was 40±5%, and IOP (P0) was 15.7±4.1 (9.1-18.5) mm Hg. Complete hypotensive success was achieved in 83.6% of cases in the control group and 96.2% in the main group in 6 months; 68.07% and 92.59% in 12 months; 41.3% and 75.8% in 24 months; 15.25% and 48.93% in 36; 15% and 34.8% in 60 months after the surgery, respectively (p=0.0001, 95% confidence interval). TDM is an additional level of retention of aqueous humor and plays key role in the formation of outflow pathways after NPDS. Performing LGP in the early postoperative period is an effective and safe adjuvant option, which excludes the influence of TDM on the formation of aqueous humor outflow pathways and significantly increases the long-term hypotensive efficacy of non-penetrating deep sclerectomy.