Norman D. Radtke

State of the art retina and vitreous research and treatment

[Norman D. Radtke @NRadtkeMD]

Clinical findings of most inherited retinal diseases are rarely pathognomic of a single genetic mutation, with few exceptions. The lack of genotype-phenotype correlations is one of the most critical factors in trying to determine the genetic makeup of a clinical presentation.

[Norman D. Radtke @NRadtkeMD]

The most common clinical subgroup among all generalized progressive photoreceptor inherited retinal dystrophies is retinitis pigmentosa, a diverse group of peripheral retinal dystrophies affecting the photoreceptors and the retinal pigment epithelium.

[Norman D. Radtke @NRadtkeMD]

The most common clinical subgroup among all generalized progressive photoreceptor inherited retinal dystrophies is retinitis pigmentosa, a diverse group of peripheral retinal dystrophies affecting the photoreceptors and the retinal pigment epithelium.

[Norman D. Radtke @NRadtkeMD]

A clear one-to-one genotype-phenotype correlation is rare in inherited retinal diseases. For this reason, a clinical diagnosis in the absence of genetic testing is incomplete.

[Norman D. Radtke @NRadtkeMD]

To date, more than 260 genes causing inherited retinal diseases have been identified and another 37 have been mapped to a chromosomal location with gene identification in progress.

[Norman D. Radtke @NRadtkeMD]

Nearly two-thirds of inherited retinal diseases are photoreceptor diseases. In most, if not all, photoreceptor dystrophies, the function of both rod and cone systems is compromised, sometimes in the early stages of the disease.

[Norman D. Radtke @NRadtkeMD]

The recent approval of the first gene therapy for retinal dystrophies caused by biallelic RPE 65 mutations signal is the dawn of a new era in caring for patients with inherited retinal dystrophies.

[Norman D. Radtke @NRadtkeMD]

Inherited retinal diseases are a class of rare, single-gene disorders that represent the major cause of familial blindness in the world, and until recently, have been untreatable

[Norman D. Radtke @NRadtkeMD]

The American Diabetes Association currently recommends that most patients with diabetes and hypertension should be treated to a blood pressure goal of 140/90 mmHg.

[Norman D. Radtke @NRadtkeMD]

The association between blood pressure and diabetic retinopathy varies among studies, but in the population – based META-EYE study, diabetic retinopathy prevalence was increased in hypertensive (40%) compared with normotension (31%) patient.

[Norman D. Radtke @NRadtkeMD]

Several studies have shown that the primary risk factor for diabetic retinopathy is the duration of the patient’s diabetes.

[Norman D. Radtke @NRadtkeMD]

Hyperglycemia is a modifiable risk factor for most diabetic complications including retinopathy. Each 1% decrease in A1C is associated with a reduction in retinopathy risk of approximately 40%, progression to vision – threatening retinopathy by 25% and blindness by 15%.

[Norman D. Radtke @NRadtkeMD]

While the mechanisms are not yet understood, drusen, small yellowish deposits of cellular debris that form between the retinal pigment epithelium and Bruch’s membrane, have been identified as a significant risk factor for the development of advanced AMD.

[Norman D. Radtke @NRadtkeMD]

Immune dysfunction appears to play a significant role in the development of AMD. Over activities of the complement pathway in genetically predisposal individuals puts patients at higher risk to develop AMD.

[Norman D. Radtke @NRadtkeMD]

The etiology of AMD is believed to be multifactorial. One hypothesis on the causes of AMD suggests that a combination of oxidative stress, genetic predisposition and environmental factors may all contribute to accumulation of complement deposition.

[Norman D. Radtke @NRadtkeMD]

The AREDS 2 formulation is recommended in elderly populations at risk of AMD to supplement their normal diets.

[Norman D. Radtke @NRadtkeMD]

As AMD is an ocular disorder affected by systemic factors, it would be expected that both eyes would be equally affected. Further study into the area is warranted to provide answers to the mechanisms of advanced AMD.

[Norman D. Radtke @NRadtkeMD]

One of the curiosities of AMD is that it frequently appears asymmetrically when large drusen and other signs, such as pigment changes, are present in one eye, while the other will appear essentially age – normal.

[Norman D. Radtke @NRadtkeMD]

Neovascular AMD is primarily a vascular endothelial growth factor (VEGF) – mediated event, while the hallmark of geographic atrophy is the appearance of drusen produced through an inflammatory response, both involving photoreceptor degeneration.

[Norman D. Radtke @NRadtkeMD]

Higher concentrations of zinc are seen within the RPE and the retina in younger patients, but over time and with age, the zinc level declines.