Abstract
Purpose: :
To evaluate whether frequency doubling perimetry (FDT) is a valid screening tool for open-angle glaucoma (OAG) in high-risk populations.
Methods: :
This was an observational, cross-sectional study. All subjects underwent frequency doubling Technology perimetry (FDT C-20-5 algorithm) and complete ophthalmic examination including visual acuity, gonioscopy, intraocular pressure-IOP, central corneal pachymetry-CCT, optic disc grading and fundoscopy. FDT printouts were classified according to Iwasaki and Patel protocols. Gold-standard was clinical diagnosis of glaucomatous optic nerve damage.Outcome measures: Sensitivity, specificity, positive-predictive value (PPV), negative predictive value (NPV), as well as positive and negative likelihood ratios (PLR and NLR) values of single-test screening FDT.
Results: :
495 subjects with mean age of 62 ± 11 were enrolled in the final study sample. 438 subjects (88.5%) were Caucasians and 57 (11.5%) were blacks. There were 343 (69.3%) female and 152 (30,7%) male. Depending of differents gold standard, range of results were between 40% and 78.9% for sensitivity; 66% and 70% for specificity; 7.7% and 25.2% for PPV; 82.3% and 98.3% for NPV; 1.21and 2.37 for PLR; 0.32 and 0.87 for NLR. Inter-scoring technique agreement was high with kappa of 0.940.
Conclusions: :
Although sensitivity and specificity were low, NPV was high. FDT could be used as part of a more complete glaucoma screening protocol.
Keywords: clinical (human) or epidemiologic studies: systems/equipment/techniques • visual fields • optic nerve