The course of primary open angle glaucoma in a patient with subcompensated non-insulin dependent diabetes type 2

Оphthalmic manifestations of diabetes mellitus include changes in the circulation of aqueous humor, increase or decrease in the level of intraocular tension, abnormal permeability of the blood-aqueous barrier, and anomalies of the retinal vessels. A balanced approach to the choice of treatment tactics is a basis for treatment of Primary Open Angle Glaucoma. The criterion for the effectiveness of glaucoma surgery is sustained normalization of intraocular tension and preservation of visual functions. Surgical treatment of glaucoma in patients with severe somatic pathology is accompanied by a high risk of postoperative complications: hyphema, ciliochoroidal detachment, hemophthalmos, repeated increase in intraocular tension, etc. Diabetes mellitus as a systemic disease causes widespread vascular autonomic and endothelial dysfunction. The reasons for the decrease in the hypotensive effect of glaucoma surgery in such patients is excessive cicatrization of the newly created fluid outflow tracts with the formation of adhesions between the conjunctiva and the sclera, the scleral flap and underlying tissues. It leads to a repeated increase in intraocular tension in the late postoperative period. Therefore, the choice of tactics for the management and treatment of patients with glaucoma and with severe comorbidity requires an individual and measured approach.

Evaluation of Aqueous Flare Intensity in Eyes Undergoing Intravitreal Bevacizumab Therapy to Treat Neovascular Age-Related Macular Degeneration

Purpose: To evaluate the effect of repeated intravitreal bevacizumab injections on blood-aqueous barrier permeability in eyes with neovascular age-related macular degeneration (AMD).Patients and Methods: Forty-eight consecutive patients with neovascular AMD received 3 intravitreal bevacizumab injections (1 mg) every 30–40 days. Subjects were followed for a period of 4 months and were examined at baseline, 1 day and 1 month after each injection. A control group comprised of 19 neovascular AMD patients waiting to begin anti-vascular endothelial growth factor (VEGF) therapy. Anterior chamber (AC) inflammation was evaluated with biomicroscopy and laser flare photometry.Results: None of the subjects treated with bevacizumab had detectable ocular inflammation during follow-up. An analysis for variance (ANOVA) of the mixed-effects model has shown neither an effect between treatment and control group (p = 0.921), nor over the time course of the follow-up (p = 0.773). Before treatment, median AC inflammation was 6.7 photons/ms (range: 3.5–18.2 photons/ms). One month after the first, second, and third injections, median laser flare was 6.4, 6.8, and 6.6 photons/ms, respectively, none of which were significantly different from baseline (all p > 0.05). Blood-aqueous barrier permeability did not change between injections and was not different from the control group.Conclusion: Inflammation induced by intravitreal bevacizumab was not detected by examination or flare photometry. This suggests that monthly bevacizumab dosing seems to be safe. The absence of AC inflammation could also reflect the known anti-inflammatory properties of anti-VEGF agents.

Nanoscale Drug Delivery Systems for Glaucoma: Experimental and In Silico Advances

: In this review nanoscale based drug delivery systems particularly in relevance to the antiglaucoma drugs have been discussed. In addition to that, the latest computational/in silico advances in this field are examined in brief. Using nanoscale materials for drug delivery, is an ideal option to target tumours and drug can be released at areas of the body where traditional drugs may fail to act. Nanoparticles, polymeric nanomaterials, single-wall carbon nanotubes (SWCNTs), quantum dots (QDs), liposomes and graphene are the most important nanomaterials used for drug delivery. Ocular drug delivery is one of the most common and difficult tasks faced by pharmaceutical scientists because of many challenges like circumventing the blood–retinal barrier, corneal epithelium and the blood–aqueous barrier. Authors found compelling empirical evidence of scientists relying on in-silico approaches to develop novel drugs and drug delivery systems for treating glaucoma. This review in nanoscale drug delivery systems will help us in understand the existing queries and evidence gaps and will pave way for effective design of novel ocular drug delivery systems

Flaremetric evaluation of blood-aqueous barrier breakdown in diabetic patients after phacoemulsification and intraocular lenses with or without heparin-coated surface implantation

Background: This study compared the intensity of blood-aqueous barrier breakdown in diabetic patients after phacoemulsification with heparin surface-modified and non-modified intraocular lens (IOL) implantation. Material and methods: In this prospective trial, 68 diabetic patients were enrolled and divided into two groups: 33 patients with heparin surface-modified IOL implants (group 1) and 35 patients with standard hydrophobic IOL implants (group 2). Blood-aqueous barrier breakdown was assessed using a Laser Flare Meter 1 day, 7 days, 14 days, 1 month, and 3 months postoperatively. Results: On postoperative days 1 and 7, the mean flare value was significantly higher in group 2 compared with group 1. On day 14, the mean flare value in both groups was similar and then higher in group 2. Conclusions: The implantation of foldable heparin-coated IOLs led to a lower intensity and faster recovery of blood-aqueous barrier breakdown postoperatively.

Selective permeability of mouse blood-aqueous barrier as determined by 15N-heavy isotope tracing and mass spectrometry

The blood-aqueous barrier plays a key role in regulating aqueous humor homeostasis by selectively restricting passage of proteins into the eye. The kinetics of aqueous flow are traditionally measured using artificial markers; however, these marker molecules do not address the barrier’s selective permeability to plasma proteins. Here we applied stable isotope labeling of all serum proteins with nitrogen-15 (15N) atoms. Following systemic injection of this “heavy” serum in mice, the 15N-to-endogenous nitrogen-14 (14N) ratio of each protein in aqueous was measured by mass spectrometry. By monitoring the kinetic changes in these ratios, we determined the permeability profiles of hundreds of serum proteins. Meanwhile, we subjected one of the eyes to neoangiogenic wound healing by inflicting injury to the corneal limbus and compared the 15N proteomes between the normal eyes and the recovering eyes at 2 weeks after injury. In the injured eye, we detected markedly enhanced permeability to inhibitory complement regulator proteins, such as Cfh, Cfhr, Cfb, Cfi, Cfd, and Vtn. Many of the proteins in this group are implicated in age-related macular degeneration associated with leakage of the blood-retinal barrier due to inflammation. To rule out the possibility that the observed leakage was due simply to physical damage of the blood vessels, we separately created a neovascularization model using an alkali burn of the avascular cornea. In this latter model, elevated levels of Cfh and Cfb were evident. These findings suggest that ocular neovascularization is associated with enhanced permeability to serum complement regulators.