Comparison of objective assessment using the sweep pattern visual evoked response acuity (SPVERA) and illiterate E visual acuity.
- Author:
Rui-Jue LIU
1
;
Hai-Yan LIU
Author Information
1. Institute of Forensic Science, Ministry of Justice, P. R. China, Shanghai 200063, China.
- Publication Type:Journal Article
- MeSH:
Adult;
Evoked Potentials, Visual/physiology*;
Female;
Fourier Analysis;
Humans;
Male;
Middle Aged;
Pattern Recognition, Visual/physiology*;
Photic Stimulation;
Vision Disorders/physiopathology*;
Vision Tests/methods*;
Visual Acuity/physiology*
- From:
Journal of Forensic Medicine
2006;22(5):342-345
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To compare the vision objectively assessed by SPVERA with the illiterate E Acuity in normal subjects.
METHODS:The effect of artificially induced image defocusing on visual acuities (Vas) measured by SPVEP and illiterate E chart measurement was studied in 14 normal subjects. SPVEP was recorded using vertical gratings of 8 different spatial frequencies ranging from 0.235 9 to 30.203 2 c/deg. The responses were averaged and displayed through the discrete Fourier transform on the monitor display. SPVERA was determined by extrapolating the PVER amplitude -spatial frequency function to baseline. SPVERA was compared with illiterate E visual acuity measured under the same conditions of optical defocus.
RESULTS:With moderate defocusing (<+1.0 diopter (D),VA > 0.42), the SPVERA were equal to or poorer than the illiterate E visual acuity. With more defocus (> +2.0 diopter (D), VA < 0.3),the SPVERA became better than the illiterate E chart Visual Acuity. The correlation between the two acuities was r2 = 0.919.
CONCLUSION:SPVERA and the illiterate E visual acuity correlated to a certain degree. We conclude that the SPVERA is effective in estimating vision objectively.
