Unveiling the Nanotechnology-Based Drug Delivery Systems and Patent Literature for Diabetic Retinopathy

Diabetes mellitus is a principal reason for globally developing chronic microvascular disorders defined as diabetic retinopathy (DR). Proliferative retinopathy and non-proliferative retinopathy are the two types of DR. Long-term diabetes, and poor blood sugar and arterial blood pressure regulation are the key risk factors for the onset and advancement of DR. A variety of biochemical pathways are involved in the pathogenesis of DR, which includes increased polyol pathway fluxes, advanced glycation end product growth, protein kinase C isoform activation, and increased hexosamine pathway flux. The varieties of cells are involved in diabetic retinopathy, including glial cells, retinal ganglion cells, endothelial cells, and pericytes. Surgical treatment of DR includes laser treatment, panretinal photocoagulation, focal laser photocoagulation, and vitrectomy surgery. The systemic treatment of DR includes glycemic management and control of blood pressure and hyperlipidemia. Nanotechnology-based formulations like nanoparticles, polymeric nanomicelles, and nanocarrier composite, and various patented formulations have been investigated for the treatment of DR.

Results of complicated cataract surgery in patients with neovascular glaucoma in case of diabetic proliferative retinopathy or postthrombotic macular edema

Objective. To evaluate the results of complicated cataract surgery in patients with neovascular glaucoma in case of diabetic proliferative retinopathy or postthrombotic macular edema. Material and methods. A retrospective study of the complicated cataract surgery with IOL implantation results was performed in 38 patients (38 eyes) with neovascular glaucoma. The first stage was Lucentis intravitreal injection, then after 2 weeks intraocular pressure (IOP) under combined medical therapy was determined: 1) if IOP was <25 mm Hg, then phacoemulsification was performed; 2) if IOP remained >25 mm Hg, the second stage was transscleral cyclophotocoagulation, and 2 weeks later – cataract phacoemulsification. Results. All patients with neovascular glaucoma had significant increase of the best corrected visual acuity from the initial level on the 1st day, 1- and 3-months post-op. IOP values under medical treatment corresponded to the range of the average statistical norm. There was no recurrence of neovascularization or IOP increase. Conclusion. The application of Lucentis intravitreal injections as well as IOP lowering to the average statistical norm range under medication or laser surgery provide the basis for an effective and safe complicated cataract surgery with IOL implantation in patients with neovascular glaucoma in case of diabetic proliferative retinopathy or post-thrombotic macular edema. Key words: cataract, neovascular glaucoma, phacoemulsification.

The Role of Growth Hormone and IGF-1 in Retinopathy: A Prospective Study of Retinopathy in Patients with Acromegaly and Impaired Fasting Glucose

Aims To investigate the effects of the GH-IGF-1 axis on the incidence and progression of retinopathy. Methods We enrolled 91 patients with acromegaly and 123 subjects with impaired fasting glucose (IFG) between 2008 and 2016 to examine the incidence and prevalence of retinopathy. Patients attended follow-ups in our clinics and underwent examinations according to the national guidelines for diabetes management. Both cohorts attended follow-ups until June 2019. Results Both groups had similar HbA1c, cholesterol, and blood pressure levels. However, patients with acromegaly had higher GH (8.05±16.18 vs. 0.78±1.25 ng/mL) and IGF-1 (547.0±342.1 vs. 146.7±51.4 ng/mL) levels than in subjects with IFG. During the follow-up period, eight patients (8.8%) with acromegaly and 12 patients (9.8%) with IFG developed some degree of retinopathy. Three patients with acromegaly and two with IFG progressed to proliferative retinopathy. Patients with acromegaly had the same incidence of non-proliferative retinopathy (odds ratio [OR]: 0.830; 95% CI: 0.318–2.164) and a non-statistically significantly higher incidence of proliferative retinopathy (OR: 2.461; 95% CI: 0.404–14.988). Conclusion The data reveals that GH and IGF-1 might play a crucial role in the development of proliferative retinopathy and influence its progression. Therefore, we suggest screening patients with acromegaly should be similar to diabetes patients.

Role Of Colour Doppler Imaging In Early Diagnosis Of Diabetic Retinopathy

Diabetic retinopathy is the most common cause of vision loss among people with diabetes and a leading cause of blindness among working-age adults in India. It is a form of microangiopathy, and is the most common ocular complication seen in diabetic patients. Diabetic retinopathy progresses from non proliferative to proliferative retinopathy. The non proliferative retinopathy is the milder form and it is reversible. As the progression to proliferative retinopathy happens, the patients are symptomatic and become irreversible. Vascular changes and subsequent ocular hemodynamic changes are critical events in the pathogenesis of diabetic retinopathy. Colour doppler imaging is one of the most widely used and well-established techniques for assessing ocular blood flow velocities in the retro bulbar vessels. This is a non-invasive, painless imaging method with highly reproducibility. Estimation of orbital blood flow velocity from colour doppler imaging of the ophthalmic artery and central retinal artery is a technique offering great potential for the identification of early retinopathy in diabetic patients.

Further Analysis on Characteristic of Diabetic Reinopathy - A Case in Thai Binh Province in Vietnam

Objective: to study the characteristics of the diabetic retinopathy and some related factors in patients with type 2 diabetes. Subject and research methods: a cross-sectional descriptive study on 80 patients with type 2 diabetes to be examined and treated at the Internal Medicine Department of Thai Binh Medical University Hospital from January to December 2019. Result: • The percentage of patients with damage to the retina accounts for 42.5%; of which, 38.8% were nonproliferative retinopathy, 17.5% were macular disease, 2.5% were pre-proliferative retinopathy and 1.2% were proliferative retinopathy. • The risk of retinal damage increased higher in women than in men; the OR coeffecient of subgroups, namely age ≥ 70 years; diabetic duration ≥ 10 years; BMI ≥ 23 (kg/m2), hypertension, was 1.4; 2.5; 4.0; 4.5; 2.5, respectively. Patients with blood glucose ≥ 7 mmol/L, HbA1c ≥ 7%; total cholesterol > 5.2 mmol/L, triglyceride > 1.88 mmol/L had higher risk of retinopathy with OR coefficient of 2.3; 2.5; 3.2; 2.0, respectively. Patients who were non-compliance with treatment had 3.8 times higher risk of retinopathy than those who complied with treatment. Conclusion: the percentage of patients with retinopathy was 42.5%, the risk of retinopathy increased in patients with one of the following characteristics: female, age ≥ 70 years, duration of diabetes ≥ 10 years, BMI ≥ 23 (kg / m2), hypertension, blood glucose concentration ≥ 7 mmol/L, HbA1c ≥ 7%; cholesterol> 5.2 mmol/L, triglyceride> 1.88 mmol/L.

Hypertension as an Unusual Cause of Proliferative Retinopathy: Case Report and Literature Review

Malignant hypertensive retinopathy is associated with characteristic fundus findings that typically do not include proliferative retinal vascular changes. We present the case of a 34-year-old patient who had bilateral decreased vision and was found to have malignant hypertension with hypertensive retinopathy changes along with unforeseen bilateral neovascularization and vitreous hemorrhage. Detailed history and extensive systemic and ophthalmic workup failed to reveal an alternative explanation for her proliferative retinopathy. Blood pressure control and panretinal photocoagulation halted further deterioration. Malignant hypertensive retinopathy can rarely cause profound retinal ischemia leading to retinal neovascularization. This case further supports the presence of “proliferative hypertensive retinopathy” that needs to be identified and addressed urgently through collaboration between internists and ophthalmologists.