ABSTRACT
Snellen letter and Vistech sine wave grating charts were used as refraction targets to determine differences in times required to accomplish subjective refractions, endpoint refractive values, and subject preferences. Thirty hyperopes and 30 myopes, divided into three age groups, were selected as subjects. Two examiners tested each subject using each chart. Both timed their subjective refractions and recorded their findings. After all data were recorded, each subject completed a questionnaire to determine chart preference. There were no clinically significant mean differences between the charts in terms of endpoint refractive data, but, on average, the Snellen chart was faster to use. Chart rating depended on the subject's refractive status with more myopes preferring the Snellen chart and more hyperopes rating the grating chart higher.
Subject(s)
Refractive Errors/diagnosis , Vision Tests/standards , Adolescent , Adult , Analysis of Variance , Child , Humans , Hyperopia/diagnosis , Middle Aged , Myopia/diagnosis , Time FactorsABSTRACT
This study evaluated the effects of head and gaze position on near fixation disparity, phoria, and duction findings. A population of 104 non-complaining subjects divided by age into 3 groups participated in the study. The primary head and gaze position along with two others approximating the positions used for reading by nonbifocal and bifocal wearers were used. A statistically significant effect was found for the phoria data from the young group, but the magnitude was clinically insignificant. Changes in head and/or gaze positions did not significantly affect fixation disparities or duction recovery ranges. Phorias and fixation disparities showed statistically significant increases in exo deviation with increasing age regardless of head and/or gaze position. Nine of 23 presbyopic subjects gave erratic findings during fixation disparity testing and this casts doubt upon the clinical usefulness of this procedure with presbyopes.
Subject(s)
Fixation, Ocular , Head , Myopia/physiopathology , Strabismus/physiopathology , Adolescent , Adult , Aged , Analysis of Variance , Female , Humans , Male , Middle Aged , Posture , Presbyopia/physiopathologyABSTRACT
Four generations of a family with hereditary retinal degeneration underwent extensive optometric evaluation, including electrodiagnostic testing. The compiled data indicate a partial cone dysfunction transmitted as an autosomal dominant trait. The optometrist's role in the diagnosis of such conditions is discussed as well as his role in family counseling. The cone dysfunction under discussion is differentiated from other tapetoretinal degenerations.
