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Abstract #8394 Published in IGR 5-1
Combined use of frequency doubling perimetry and polarimetric measurements of retinal nerve fiber layer in glaucoma detection
Horn FK; Nguyen NX; Mardin CY; Jünemann AGAmerican Journal of Ophthalmology 2003; 135: 160-168
PURPOSE: The aim of this study was to evaluate the diagnostic usefulness of the combined use of frequency-doubling technology (FDT) perimetry and polarimetry of the retinal nerve fiber layer. DESIGN: Cross-sectional study. METHODS: Seventy ocular hypertensive patients (normal optic disc and standard perimetry, elevated intraocular pressure (IOP; > 21 mmHg)), 59 patients with 'preperimetric' open-angle glaucoma (glaucomatous optic disc atrophy, elevated IOP (> 21 mmHg), no visual field defect in standard perimetry), 105 patients with 'perimetric' open-angle glaucoma (glaucomatous optic disc atrophy and clearly marked visual field defect), and 73 control subjects had FDT screening (protocol: C-20-5) and polarimetric measurements (GDx). Criteria for exclusion: optic discs larger than 4 mm2, media opacities, patients younger than 33 or older than 66 years. None of the subjects had had earlier FDT perimetry. One eye of each patient and control subject entered the statistical evaluation. Database and statistical software were used for case-wise recalculation of all missed localized probability levels to create a FDT screening score. RESULTS: At a predefined specificity of 94.5% in control eyes, discrimination between 'perimetric' glaucoma and normal subjects is superior using the FDT perimetry (sensitivity = 84.8%) in comparison to polarimetry (sensitivity = 63.8%), whereas sensitivity is similar with both methods in 'preperimetric' patients (GDx, FDT: 25.4%). In several cases, patients classified as glaucomatous by the GDx are not the same patients as identified by the FDT perimetry. Therefore, a two-dimensional discrimination analysis can increase correct positive classification. Using a linear combination of the present FDT screening score and polarimetry ('the number'), 92.4% of 'perimetric' glaucoma eyes and 44.1% of 'preperimetric' glaucoma eyes have been classified as glaucomatous. CONCLUSIONS: Joint usage of polarimetry and FDT perimetry indicate that a combination of different techniques which can uncover different glaucoma properties, might be helpful in early glaucoma detection.
Dr. F.K. Horn, Department of Ophthalmology and University Eye Hospital, Friedrich-Alexander University Erlangen-Nurnberg at Erlangen, Erlangen, Germany. folkert.horn@augen.imed.uni-erlangen.de
Classification:
2.13 Retina and retinal nerve fibre layer (Part of: 2 Anatomical structures in glaucoma)
6.6.2 Automated (Part of: 6 Clinical examination methods > 6.6 Visual field examination and other visual function tests)
6.9.1 Laser scanning (Part of: 6 Clinical examination methods > 6.9 Computerized image analysis)
