Fundus automated perimetry is a technique that images the retina during visual field testing, enabling a correlation to be made between visual function and retinal structure.1
Advantages of Fundus Automated Perimetry over Standard Automated Perimetry include the possibility to measure sensitivity at specific retinal locations, higher accuracy thanks to retinal-tracking based compensation of eye movements and the simultaneous assessment of function (expressed by retinal sensitivity) and structure (images of the ONH, of the RNFL and of the retina). Fundus Automated Perimetry provides a simultaneous, quantitative assessment of fixation characteristics.
Use of Fundus Automated Perimetry in the clinical management of glaucoma has been limited so far, as available systems were lacking compliance with the standards of automated perimetry. COMPASS overcomes such limitations and brings visual field analysis to the next level!
In particular COMPASS, for the first time, extends field coverage to 30° + 30° and employs luminance parameters and a sensitivity scale as used in standard automated perimetry.
The above information on this page is copied from the company website http://www.centervue.com/products/compass/
The enhanced Glaucoma Staging System (GSS 2) of Brusini classifies visual field defects based on the perimetric indices MD (Mean Deviation) and PSD (Pattern Standard Deviation). The representative point of the examination is placed in a chart according to the values of these indices. The chart displays defined areas for the different stages of disease (Stage 0 – Stage 5) and separates generalized, localized and mixed defects.
|Stage||Gravity and Visual Field Findings|
|“S0″||Completely normal field of vision|
|Border||Very mild defect, often not statistically significant|
|S1||Slight defects, such as small relative paracentral scotomas|
|S2||Moderate defects, such as nasal step, scotomata of limited size, etc.|
|S3||Occurring defects, as fascicular absolute scotoma|
|S4||Very advanced and absolute defects, affecting at least 2 quadrants|
|S5||Sub-terminal defects, with small islands of residual sensitivity|
MD = Mean Deviation (Humphrey, Oculus) or Mean Defect (Octopus), CPSD = corrected pattern standard deviation, CLV = Corrected Loss Variance (Octopus), LV = Loss Variance
PSD (left) and LV (right), can be used when the corresponding correct indexes are not available or in the case of high values of the short-term fluctuation (SF), in which the value of CPSD is 0.
Tags: Brusini, CLV, Corrected pattern standard deviation, CPSD, glaucoma, glaucoma staging, GSS2, loss variance, LV, MD, Mean defect, Mean deviation, PSD, visual field