For normal vs. early glaucoma, the parameter with the best AROC was Nerve fiber Key Words: GDx VCC polarimetry, glaucoma, retinal nerve fiber damage. PURPOSE: To evaluate the performance of the HRT II (Heidelberg retinal tomograph) and GDx (glaucoma detection) retinal nerve fibre. Eur J Ophthalmol. Mar-Apr;16(2) Glaucoma detection using the GDx nerve fiber analyzer and the retinal thickness analyzer (RTA). Hoffmann EM(1).

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That should be enough to make it a good test. The answer is probably yes, the machine can measure changes in thickness that the MD cannot. Invest Ophthalmol Vis Sci.

Glaucoma detection using the GDx nerve fiber analyzer and the retinal thickness analyzer (RTA).

In all statistical analyses, we set significance at 0. The superior glauckma inferior poles are usually affected first. While visual field is a subjective exam lasting minutes, we can now image glaucomatous damage in an exam that lasts only a few minutes, does not require pupil dilation, and is completely objective.

All subjects underwent were assessed by means of the GDx VCC imaging technique within 3 months of the clinical examination and visual field testing. Our previous report also showed that GDx VCC shows only a moderate ability to distinguish normal eyes from eyes with early glaucoma mean MD: Do most glaucoma specialists have access to GDx? It is not always g,aucoma glaucoma, so care must glaucomw taken. Therefore, I am not so confident about it.

However, an interesting result that was pointed out is that the correlation seemed to be stronger for the moderateglaucoma subgroup, compared to that obtained for the severe- or the early-glaucoma subgroup.


Glaucoma Service Foundation Web Blog

Imaging Optic Nerve Damage Glaucoma is a common disease, which usually occurs, in older age. Garbage in, garbage out.

It may be fine, but I would rather look at things like the area of the rim. It is scientifically reasonable to think that the NFI might always be the best parameter for differentiating glaucomatous eyes from normal ones.

The variable corneal compensator was then set so as to neutralize the anterior corneal birefringence, and the retinal retardation was imaged and measured.

As far as the classification of glaucoma severity is concerned, several methods have been proposed to grade glaucoma on the basis of visual field changes detected on standard white-on-white perimetry. The sensitivity and specificity of nerve fiber layer measurements in glaucoma as determined with scanning laser polarimetry. The top and bottom of the nerve also happen to be the first areas usually affected by glaucoma.

There is a significant difference in MD between the normal group and each glaucoma subgroup. The box plots for NFI also ydx a considerable overlap between several glaucoma subgroups Figure 2. Statistical analysis indicates severity of damage at each and every point. But both are still experimental.

The three parameters showing the best AROC curves when it comes to discriminating between the various subgroups. The GDx VCC device glauco,a the retardation of the two components of a polarized laser beam in nanometers and a fixed conversion factor was used to calculate the corresponding RNFL thickness in micrometers.

Do you happen to know how the database for this program was set up? Glaucomaa of automated visual field parameters and peripapillary nerve fiber layer thickness as measured by scanning laser polarimetry. The idea is that in glaucoma you have focal loss of tissue, whereas aging causes diffuse loss.


Quantitative correlation of nerve fibre loss and visual field defect in glaucoma, ischemic neuropathy, papillodema and toxic neuropathy.

The vlaucoma of atypical birefringence patterns on glaucoma detection using scanning laser polarimetry with variable corneal compensation.

There is a statistically significant correlation between each of the abovementioned parameters and PSD for each glaucoma subgroup as well as for the glaucoma group as a whole. Although we chose our glaucoma group according to an experienced doctor, it is inevitable that these patients were identified on the basis of particular patterns of structural and functional abnormalities that met preconceived notions, which may result in a biased outcome of the comparison.

What is the meaning of the colors and the green circle in the GDx example above? Diagnostic capability of optical coherence tomography in evaluating the degree of glaucomatous retinal nerve fiber damage. Second, the difference in age between the normal healthy subjects and the glaucoma patients may also constitute a source of bias that may increase the discriminating power of GDx VCC for glaucoma detection in this study.

Articles from Journal of Optometry are provided here courtesy of Elsevier. I am not sure if it is the test of the future.

GDx Nerve Fiber Analyzer – Glaucoma Service Foundation to Prevent Blindness

Purchase this article with an account. How can you tell the nerve fiber layer is bad? The thinning may show up earlier than with a field test, but remember that until there is a field defect, you are unaware of a problem.