title: Psychophysical assessment of low visual function in patients with retinal degenerative diseases (RDDs) with the Diagnosys full-field stimulus threshold (D-FST).
abstract: To determine whether the Diagnosys full-field stimulus threshold (D-FST) is a valid, sensitive and repeatable psychophysical method of measuring and following visual function in low-vision subjects. Fifty-three affected eyes of 42 subjects with severe retinal degenerative diseases (RDDs) were tested with achromatic stimuli on the D-FST. Included were subjects who were either unable to perform a static perimetric field or had non-detectable or sub-microvolt electroretinograms (ERGs). A subset of 21 eyes of 17 subjects was tested on both the D-FST and the FST2, a previous established full-field threshold test. Seven eyes of 7 normal control subjects were tested on both the D-FST and the FST2. Results for the two methods were compared with the Bland-Altman test. On the D-FST, a threshold could successfully be determined for 13 of 14 eyes with light perception (LP) only (median 0.9 +/- 1.4 log cd/m2), and all eyes determined to be counting fingers (CF; median 0.3 +/- 1.8 log cd/m2). The median full-field threshold for the normal controls was -4.3 +/- 0.6 log cd/m2 on the D-FST and -4.8 +/- 0.9 log cd/m2 on the FST2. The D-FST offers a commercially available method with a robust psychophysical algorithm and is a useful tool for following visual function in low vision subjects.
authors.affiliation: Retina Foundation of the Southwest, 9900 N. Central Expressway, Suite 400, Dallas, TX 75231, USA. mklein@retinafoundation.org
authors.forename: M
authors.initials: M
authors.lastname: Klein
authors.forename: D G
authors.initials: DG
authors.lastname: Birch
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002648:Child; D002675:Child, Preschool; D004596:Electroretinography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D015203:Reproducibility of Results; D012162:Retinal Degeneration / Q000150:complications / Q000503:physiopathology*; D012680:Sensitivity and Specificity; D012684:Sensory Thresholds; D015354:Vision, Low / Q000209:etiology / Q000503:physiopathology*; D058609:Visual Field Tests