Abstract
Abstract: :
Purpose: To investigate the relation between the intrascleral space at the site of sclerectomy, as visualized by ultrasound biomicroscopy (UBM), and intraocular pressure after combined viscocanalostomy and small incision cataract surgery in 84 eyes with POAG or ocular hypertension and cataract. Methods: In a prospective, noncomparative, observational study, UBM examination of the sclerectomy site was performed at 3, 6, and 12 months after surgery. Three parameters of the radial image of the lake: the area, the length of trabeculo-Descemet’s membrane, and the longitudinal length, were assessed and correlated with both the levels of intraocular pressure and the magnitude of IOP reductions at each time. The survival of the lake by UBM examination was studied with Kaplan-Meier analysis. Results: Mean intraocular pressure decreased from a preoperative value of 19.8±3.5mmHg (mean±S.D.) to a postoperative value of 15.2±2.7mmHg at 12 months. Significant reductions were observed between 3 and 12 months (P<0.0001). A negative correlation was found between the IOP reduction and lake size at 3 months (Rs=-0.255, p=0.043). At 6 months, both the area and the longitudinal length had a negative correlation with the IOP (Rs=-0.262, p=0.033, and Rs=-0.270, p=0.028, respectively). The length of trabeculo-Descemet’s membrane at 6 months had a positive correlation with IOP decrease (Rs=0.321, p=0.005) and a negative correlation with IOP (Rs=-0.343, p=0.009). However, no parameters were correlated with the level of IOP nor the reduction of IOP decrease at 12 months. The detectable rate of the lake at postoperative 12 months was 64.3%. Conclusion: The lake size at 12 months decreased comparing with that at 3 months. No correlation was found between the lake size and IOP-lowering effect at 12 months, after the relation were changed variously.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, S • imaging/image analysis: clinical • clinical (human) or epidemiologic studies: out