Inter-Device Reproducibility of the Scanning Laser Polarimeter with Variable Cornea Compensation
E.Z. Blumenthal and S. Frenkel
Invest Ophthalmol Vis Sci 2003;44: E-Abstract 3390. © 2003 ARVO 3390 – B93
Dept of Ophthalmology, Hadassah University Hospital, Jerusalem, Israel
Commercial Relationships: E.Z. Blumenthal, Laser Diagnostic Technologies F; S. Frenkel, None.
PURPOSE: To evaluate the inter-device reproducibility of retinal nerve fiber layer (RNFL) thickness measurements obtained with the commercially available GDx-VCC, a scanning laser polarimeter with variable (individualized) corneal compensation.
METHODS: One eye each, from three normal subjects was tested on 13 different GDx-VCC devices, on the same day, by an experienced operator. Reproducibility for each of 5 GDx parameters was calculated.
RESULTS: For each of five tested GDx parameters, the averaged standard deviation (µm), coefficient of variation and 95% confidence interval range (µm), respectively, were: TSNIT average: 3.18µm, 5.06%, 3.84µm; superior average: 3.99µm, 5.27%, 4.82µm; inferior average: 4.55µm, 6.08%, 5.50µm; TSNIT standard deviation: 1.89µm, 8.63%, 2.92µm; the Number (also referred to as nerve fiber indicator): 4.71, N/A, 5.69. For each of the 5 GDx parameters, repeated measures ANOVA was non-significant for inter-device differences.
CONCLUSIONS: With the commercially available GDx-VCC our results indicate that the RNFL measurements appear reproducible across devices.
Keywords: imaging/image analysis: clinical imaging methods (CT, FA, ICG, MRI, OCT, RTA) clinical (human) or epidemiologic studies