Background and Objectives: The presence of refractory cases resistant to anti-vascular endothelial growth factor (VEGF) therapy for diabetic macular edema (DME) is a problem in clinical practice. This study aimed to explore the less responsive area of optical coherence tomography (OCT) 3D map the characteristics of naïve DME cases after their first anti-VEGF. Materials and Methods: In 46 patients with DME who received an intravitreal injection of anti-VEGF agents, retinal thickness in 100 sections of the macular area was measured by 3D-mapping mode using OCT before and 1 month after injection. The density of the microaneurysm (MA) was calculated using merged images of the OCT map and fluorescein angiography. Results: One month after injection, the central retinal thickness significantly decreased (p < 0.0001). In severe edema (retinal thickness more than 500 µm), the area percentages with a reduction rate of the retinal thickness greater than 30% and less than 5% were 6.4 ± 6.6% and 10.1 ± 4.6%, respectively. The reduction rate of the retinal thickness varied from section to section. The mutual distance between the areas of maximum thickness before and after the injection averaged 1.22 ± 0.62 mm apart. The reduction rate of retinal thickness in the thickest region before injection was significantly higher (p = 0.02), and that in the thickest region after injection was lower (p = 0.001) than in the other regions. MA density in the residual edema was significantly higher than in the edema-absorbed area (p = 0.03). Conclusion: DME has areas that show low response to the reduction in retinal thickness with anti-VEGF therapy. A high density of MA may be associated with this pathogenesis.

Background: Bacterial endophthalmitis is a rare but serious complication of intravitreal injections (IVIs). Prefilled syringes have been introduced to reduce contamination risk during drug preparation. However, whether they lower the incidence of bacterial endophthalmitis compared to vials remains unclear. Methods: This retrospective cohort study analyzed aflibercept IVIs performed at 17 clinical centers in Japan between 2015 and 2022. Patients aged ≥20 years who received aflibercept IVIs (vial or prefilled syringe) for age-related macular degeneration, diabetic macular edema, retinal vein occlusion, or myopic choroidal neovascularization were included. Bacterial endophthalmitis was diagnosed based on clinical signs (e.g., rapid vision loss, pain, hypopyon, vitreous opacity). Incidence rates were compared using Fisher’s exact test. Results: Among 152,039 injections (43,684 prefilled syringes; 108,355 vials), 12 cases of bacterial endophthalmitis were identified (0.0046% vs. 0.0092%, p = 0.53). Poor visual outcomes were associated with Enterococcus faecalis, Streptococcus spp., and diabetes. Conclusions: Although incidence was lower in the prefilled syringe group, the difference was not statistically significant. Detecting a significant difference requires a larger sample. Further studies are needed to confirm the potential benefits of prefilled syringes in reducing endophthalmitis risk.

Diabetic macular edema (DME) induces visual disturbance, and intravitreal injections of anti-vascular endothelial growth factor (VEGF) drugs are the accepted first-line treatment. We investigate its impact on glycemic control after starting VEGF treatment for DME on the basis of a questionnaire and changes in hemoglobin A1c (HbA1c). We conducted a retrospective multicenter study analyzing 112 patients with DME who underwent anti-VEGF therapy and their changes in HbA1c over two years. Central retinal thickness and visual acuity significantly improved at three months and throughout the period after initiating therapy (p < 0.0001); a significant change in HbA1c was not found. A total of 59.8% of patients became more active in glycemic control through exercise and diet therapy after initiating therapy, resulting in a significantly lower HbA1c at 6 (p = 0.0047), 12 (p = 0.0003), and 18 (p = 0.0117) months compared to patients who did not. HbA1c was significantly lower after 18 months in patients who stated that anti-VEGF drugs were expensive (p = 0.0354). The initiation of anti-VEGF therapy for DME affects HbA1c levels in relation to more aggressive glycemic control.

Purpose: To evaluate the concentrations of brimonidine and brinzolamide in the vitreous and aqueous humor after instillation of a 0.1% brimonidine tartrate and 1% brinzolamide fixed-combination ophthalmic suspension. Methods: The present investigation involved patients with macular holes or idiopathic epiretinal membranes who were planning to undergo vitrectomy. One week prior to surgery, the patients received twice-daily topical treatment with 0.1% brimonidine tartrate and 1% brinzolamide fixed-combination ophthalmic suspension. Before vitrectomy, vitreous and aqueous humor samples were collected, and the mean concentrations of brimonidine and brinzolamide were determined through liquid chromatography-tandem spectrometry. Results: Ten eyes (nine phakic and one pseudophakic eyes; 10 patients) were examined. The concentration of brimonidine in vitreous and aqueous humor samples was 5.02 ± 2.24 and 559 ± 670 nM, respectively. The concentration of brimonidine in the vitreous humor, which is needed to activate α2 receptors, was >2 nM in all patients. The concentration of brinzolamide was 8.96 ± 4.65 and 1100 ± 813 nM, respectively. However, there was no significant correlation between the concentrations of brimonidine in the vitreous and aqueous humor samples. Conclusions: Sufficient concentrations of brimonidine were detected in all vitreous samples. The dissociated correlation of the drug concentrations between aqueous and vitreous humors implies the possibility of another pathway to vitreous humor, different from the pathway to aqueous humor.