Abstract
Abstract: :
Purpose: To assess the topographical relationship between structural glaucomatous damage and functional glaucomatous changes, as evaluated with Frequency Doubling Technology Perimetry (FDT). Method: Fifty eight patients with primary open angle glaucoma were examined with a Scanning Laser Ophthalmoscope (HRT, Heidelberg, Germany) and program N-30 of FDP (FDT, Humphrey Instruments, USA). Glaucoma was defined as the presence of glaucomatous changes in the optic disk evaluated with stereoscopic disk photographs, and glaucomatous changes in the program 24-2 of Humphrey Visual Field Analyzer (Humphrey Instruments, USA). Global and regional indices from HRT and FDP were analyzed with Pearson´s correlation coefficient. FDT defects were mapped and compared with HRT defective sectors. Results: No significant correlation was found between disk area and visual field parameters, either globally or regionally. Superior FDT threshold sensitivity significantly correlated with inferior HRT parameters (rim area, rim volume, and cup/disk ratio) and inferior FDT threshold sensitivity significantly correlated with superior HRT parameters. Regional mapping comparing FDT areas with 10, 20 and 30 degree HRT sectors shows variability but a clear tendency to follow certain patterns. Presently available FDT target pattern and size partially limits the chances to map the topographical distribution of functional damage with structural damage. Conclusion: Objective and quantitative mapping of functional to structural damage with FDT and HRT is feasible, and tends to follow certain topographical patterns.
Keywords: 624 visual fields • 498 optic disc • 430 imaging/image analysis: clinical