| Full text | |
| Author(s): |
Gao, Min
[1]
;
Barboni, Mirella Telles Salgueiro
[2, 3]
;
Ventura, Dora Fix
[2]
;
Nagy, Balazs Vince
[1]
Total Authors: 4
|
| Affiliation: | [1] Budapest Univ Technol & Econ, Dept Mechatron Opt & Mech Engn Informat, Budapest - Hungary
[2] Univ Sao Paulo, Dept Expt Psychol, Sao Paulo - Brazil
[3] Semmelweis Univ, Dept Ophthalmol, Budapest - Hungary
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | DOCUMENTA OPHTHALMOLOGICA; SEP 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
Purpose Human oscillatory potentials (OPs) are derived from dark-adapted (DA) electroretinograms (ERGs) with fixed frequency cutoff filters while light-adapted (LA) OPs are generally not isolated from ERGs. Our purpose was to analyze the effect of cutoff frequencies on DA and LA ERG components using a series of fixed and variable filters. Methods DA and LA ERGs were recorded from 10 healthy eyes of 10 subjects (mean age = 20.5 +/- 6.7 years) following ISCEV standards. Each signal was filtered in the Fourier domain to acquire slow (a- and b-waves; below cutoff frequency) and fast (OPs; above cutoff frequency) components. Fixed cutoff frequencies ranged from 60 to 105 Hz and a variable cutoff frequency was calculated. Results were analyzed with statistical tests and specific models. Results DA ERG components were slightly influenced by the filter cutoff frequency. In contrast, fixed and variable filters significantly changed LA components: the lower the cutoff frequency the smaller the b-wave and OP3 and the higher the OP2/OP4 amplitudes. Analyzing the filter frequency limits a transition range between 68.9 Hz and 83.9 Hz was observed where amplitudes vary. Conclusions The present report shows that DA OPs may be isolated from ERGs using filtering procedures with high-pass cutoff frequency at about 75 Hz as recommended by ISCEV. On the other hand, the spectral distribution of low-frequency and high-frequency LA ERG components may overlap. Accordingly, filtering the signal using different cutoff frequencies is not necessarily separating b-wave and OPs. (AU) | |
| FAPESP's process: | 14/26818-2 - Development and implementation of visual evaluation methods: clinical applications and animal models |
| Grantee: | Dora Selma Fix Ventura |
| Support Opportunities: | Research Projects - Thematic Grants |