The Effect of Diabetic Retinopathy and Blood Glucose Regulation on Corneal Biomechanical Parameters.

PURPOSE: The aim of this study was to evaluate the effects of different stages of diabetic retinopathy (DR) and metabolic control of blood glucose levels on corneal biomechanical parameters. METHODS: Diabetic patients were categorized into three groups: no DR group, nonproliferative DR (NPDR) group, and proliferative DR (PDR) group. Of the 141 eyes examined, 40 belonged to the control group, 34 to no DR group, 34 to NPDR group, and 33 to PDR group. Using an Ocular Response Analyzer to measure corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated IOP (IOPcc). IOP was assessed using a Tono-Pen, while central corneal thickness (CCT) was determined using an ultrasonic pachymeter. HbA1c levels were also recorded. We conducted comparisons among these groups across biomechanical parameters and IOP (tonopen), and CCT, while also investigating the impact of HbA1c levels on these parameters. RESULTS: Among any groups show a statistically significant difference in CCT, IOP (tonopen), CH, CRF, IOPg, and IOPcc. In diabetic patients, CRF, CTT, and IOPg values were significantly higher in those with HbA1c levels ≥ 7 mg/dl than in those with HbA1c levels < 7 mg/dl (p = 0.009, p = 0.013, p = 0.038), respectively, while there was no statistically significant difference in IOPcc, CH, and IOP (tonopen). Linear regression analysis showed that CH was positively associated with CCT (p < 0.001) and negatively associated with IOPcc (p < 0.001), while CRF was positively associated with CCT (p < 0.001), HbA1c (p < 0.05), and negatively associated with diagnosis of DR (p < 0.05). CONCLUSION: This study underscores the influence of metabolic control, as reflected by HbA1c levels, on corneal biomechanical parameters in diabetic patients, emphasizing the importance of monitoring and managing glycemic control in this population.

Results of fluorouracil-augmented Xen45 implantation in primary open-angle and pseudoexfoliation glaucoma.

PURPOSE: To report the effectiveness and safety of 5-fluorouracil (5-FU)-augmented Xen45 implantation in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PEXG). METHODS: This single-center, retrospective chart review study included 29 eyes that underwent 5-FU-augmented Xen45 implantation. Main outcome measures were intraocular pressure (IOP) levels and number of glaucoma medications. Surgical success was defined as IOP ≤ 21 mmHg and ≥ 20% reduction from preoperative levels without (complete success) or with (qualified success) glaucoma medications and without further glaucoma surgery at last follow-up. All postoperative interventions and complications were also noted. RESULTS: The mean age of the patients was 67.5 ± 10.3 years, and the mean follow-up time was 23.2 ± 12.6 months. Mean IOP was 24.5 ± 8.7 mmHg and decreased by 30.2% at 12 months, 24.9% at 24 months, and 31.7% at final visit (p < 0.001, p = 0.006, p > 0.001, respectively). Mean number of glaucoma medications decreased from 2.83 preoperatively to 0.71 at 12 months, 0.87 at 24 months, and 0.86 at final visit (p < 0.001). At final visit, the complete success rate was 48.3%, qualified success rate was 69%, and 62.1% of the eyes were free of glaucoma medications. Needling was performed in 7 eyes (24%). Adverse events included choroidal detachment in 5 eyes, hyphema in 2 eyes, and endophthalmitis in 1 eye. CONCLUSION: 5-FU-augmented Xen45 implantation in POAG and PEXG patients provided safe and effective IOP lowering with significant reduction of glaucoma medications up to 3 years.

Safety and efficacy of panretinal photocoagulation in patients with high-risk proliferative diabetic retinopathy using pattern scan laser versus conventional YAG laser.

The purpose of the study was to compare the results of panretinal photocoagulation (PRP) using the pattern scan laser (PASCAL) in a single setting versus multiple sessions of standard YAG laser in patients with proliferative diabetic retinopathy. Charts of 35 eyes that were treated with the PASCAL and an equal number of eyes that were treated with conventional laser were retrospectively reviewed. The whole PRP treatment was performed in one session in the PASCAL group, whereas all the patients in the conventional-laser group completed the entire PRP treatment in two or three sessions. Persistence and/or recurrence of neovascularization, complications encountered, total number of laser spots, and mean power used were compared. Patients treated with the PASCAL received significantly higher number of laser spots than those treated with conventional laser (2885 vs. 1642, p < 0.001). The PASCAL and conventional-laser systems required an average power of 650 mW and 330 mW, respectively (p < 0.001). Patients treated with the PASCAL showed similar rates of treatment failure within 12 months of follow-up compared with patients treated with conventional laser (14% vs. 11%, p > 0.05). In the PASCAL group, vitreous hemorrhage, neovascular glaucoma, retinal hemorrhage, and choroidal detachment were reported in two, two, one, and two patients, respectively, whereas only one each vitreous hemorrhage and neovascular glaucoma were encountered in the conventional-laser group. Our study reports that single-session PRP with the PASCAL has similar efficacy compared with conventional laser, and has a favorable side-effect profile.