ABSTRACT
PURPOSE: To evaluate the test-retest reliability and validity of the VAA-2000 Self Vision Tester. METHODS: A total of 108 eyes of 108 adults (55 men and 53 women) who visited Seoul National University Bundang Hospital from March to December 2015 and who had best corrected visual acuities of 20/200 or better, according to both Hahn's visual acuity test (using numbers and Landolt rings) and the VAA-2000 Self Vision Tester, were included. The test-retest reliability and validity of the VAA-2000 Self Vision Tester were assessed and compared with Hahn's visual acuity test performed using numbers and Landolt rings. The intraclass correlation, Pearson correlation, Bland-Altman plots, and Deming regression between the different tests were analyzed. RESULTS: The average best corrected visual acuity was 0.12 ± 0.17 logMAR measured with the VAA-2000 Self Vision Tester, and was 0.08 ± 0.20 logMAR with Hahn's visual acuity test using numbers and 0.08 ± 0.30 logMAR using Landolt rings. The VAA-2000 Self Vision Tester demonstrated high test-retest reliability (intraclass correlation coefficient = 0.903, p < 0.001) and acceptable validity when compared with Hahn's visual acuity test using numbers (r = 0.767, p < 0.001) and Landolt rings (r= 0.727, p < 0.001). CONCLUSIONS: The VAA-2000 Self Vision Tester possesses good reliability and acceptable validity when compared to Hahn's visual acuity test using numbers and Landolt rings.
Subject(s)
Adult , Humans , Male , Reproducibility of Results , Seoul , Vision Tests , Visual AcuityABSTRACT
Los desórdenes vestibulares como el vértigo con mayor prevalencia en la población afectada pueden diagnosticarse con diferentes herramientas incluido el test de agudeza visual dinámica. Test que a nivel clínico únicamente incluye la monitorización de velocidad de movimiento de rotación de la cabeza sin mayores herramientas que permitan el diagnóstico puntual del canal semicircular horizontal acotado en la dinámica completa del movimiento. En el presente artículo se presenta una herramienta tecnológica completa para el desarrollo del test que permite el sensado de los movimientos de la cabeza en los ejes x, y, z y la interacción con una interfaz gráfica para la evaluación de la agudeza visual con errores encontrados al final de la implementación inferiores al 2% en ángulos de inclinación y flexión y del 4% al 15% para el ángulo máximo de rotación.
Vestibular disorders as the vertigo, with higher prevalence in the affected population, can be diagnosed using different tools including the dynamic vestibular acuity test. Test including at clinical level only the speed motorization of head without more tools to allow the specific diagnose of the horizontal semicircular canal bounded in the complete dynamic of movement. This article present a complete technologic tool to the development of the test, allowing the sensing of head movements in the x, y, z axis and the interaction with a graphical interface to evaluate the visual acuity, with found differences at the end of the implementation lower of 2% in flexion and inclination angles and of 4% to 15% to the maximum rotation angle.
Distúrbios vestibulares como a vertigem, com maior prevalência na população afetada, pode ser diagnosticada através de diferentes ferramentas, incluindo o teste de acuidade vestibular dinâmico. Incluindo o teste a nível clínico somente a motorização velocidade da cabeça sem mais ferramentas para permitir o diagnóstico específico do canal semicircular horizontal delimitada a dinâmica de movimentos. Este artigo apresenta uma ferramenta tecnológica completa para o desenvolvimento do teste, Permitindo que o sensor de movimentos da cabeça nos x, y, eixo z ea interação com uma interface gráfica para avaliar a acuidade visual, com diferenças encontradas no final da Implementação inferior de 2% em ângulos de flexão e de inclinação e de 4% a 15% para o ângulo de rotação máxima.
ABSTRACT
PURPOSE: To investigate the efficacy of a computerized visual acuity test, the SNU visual acuity test for children. METHODS: Fifty-six children, ranging from 1 to 5 years of age, were included. In a dark room, children gazed at and followed a circular dot with 50% contrast moving at a fixed velocity of 10 pixels/sec on a computer monitor. Eye movement was captured using a charge coupled device camera and was expressed as coordinates on a graph. Movements of the eye and dot were superimposed on a graph and analyzed. Minimum visualized dot diameters were compared to the Teller visual acuity. RESULTS: Ten eyes (8.9%) of six children failed to perform the Teller visual acuity test, and two eyes (1.8%) of one patient failed to perform the SNU visual acuity test. The observed Teller visual acuity and SNU visual acuity were significantly correlated (p < 0.001). Visual angle degrees converted from the Teller visual acuity and SNU visual acuity were also significantly correlated (p < 0.001). CONCLUSION: The SNU visual acuity using moving targets correlated well with Teller visual acuity and was more applicable than the Teller acuity test. Therefore, the SNU visual acuity test has potential clinical applications for children.
Subject(s)
Child, Preschool , Female , Humans , Infant , Male , Diagnosis, Computer-Assisted/methods , Prospective Studies , Vision Disorders/diagnosis , Vision Tests/methods , Visual AcuityABSTRACT
PURPOSE: The objective visual acuity test is mandatory in certain cases, such as infants, nonverbal subjects, and subjects who need legal assistance. We designed an objective system for visual acuity test (SOVAT) consisting of three components: stimuli applied via a suppression method, display and evaluation and made a suppression method as stimuli component for SOVAT. Usefulness of the SOVAT was evaluated. METHODS: The visual stimuli were presented on a high-resolution head-mounted display (HMD). An eye movement tracking program and gaze monitoring device allowed us to monitor the patient's fixation status during the test. The suppression method, in addition to a conventional induction method, was developed to use with the SOVAT and its accuracy and confidence level were evaluated. RESULTS: On the basis of clinical data, we present the reference values for the SOVAT as below. For the induction method, objective visual acuity (smallest pixel size), the presumed subjective visual acuity was 3: 0.35-0.6, 7: 0.05-0.25, 12: below 0.05 and for the suppression method it was 1: 0.6-1.0, 1.5: 0.4-0.7, 3: 0.15-0.4, 5: 0.1-0.2. CONCLUSIONS: SOVAT using this suppression method to assess objective visual acuity proved to be more useful than that with a conventional induction method, especially in the range of high visual acuity.
Subject(s)
Humans , Infant , Eye Movements , Nystagmus, Optokinetic , Organothiophosphorus Compounds , Reference Values , Track and Field , Visual AcuityABSTRACT
PURPOSE: To evaluate the relationship of uncorrected visual acuity and refractive error in children. METHODS: Visual acuity testing was performed, using LogMAR chart without optical aids, in children between 4 and 11 years old. Cycloplegic refraction was carried out to check the refractive error. Correlation indices between uncorrected visual acuity (UCVA) and refractive error were obtained by regression analysis with SPSS according to the sex, age, and refractive error type, myopia, or hyperopia. RESULTS: One hundred and one children were enrolled in this study. Spherical refractive error range was -13.00D~+6.25D and cylinder range was -4.50D~0D. In the older age group, correlation indices of UCVA and refractive error increased. In addition, female patient and myopia were other components that increased the correlation indices. The formulae for the UCVA regression line and refractive error were; y=0.491e0.1492x (x=refractive error, y=UCVA), R2=0.4319. Based on the regression line, a prediction table to calculate the refractive error from the UCVA and UCVA prediction table of refractive error was made. CONCLUSIONS: For the children who are not cooperative, the prediction table of this study will be helpful to reduce the test error in visual acuity and refractive error tests.
Subject(s)
Child , Female , Humans , Hyperopia , Myopia , Refractive Errors , Visual AcuityABSTRACT
The objective visual acuity test is mandatory in certain cases, such as infants, nonverbal subjects and subjects who need legal judgements. To produce more reliable objective method, we made a new objective system for visual acuity test which is called Seohan visual acuity test(SVT). The SVT system has three elements such as stimuli, display and evaluation. For the visual stimuli, the computer program for optokinetic nystagmus(OKN)test was set up in personal computer to control the size, speed and direction of the stimuli easily. The visual stimuli are presented on HeadMounted-Display(HMD)to separate the stimuli from the environment to keep the uniform size and distance of screen to the eye of subjects and project the stimulus in full central field of patient. Electrooculography(EOG) was used to assess the visual acuity more objectively. To evaluate the usefulness of SVT, the smallest size of the stimulus to elicit OKN(objective visual acuity)with SVT was obtained in 10 eyes in each twelve grade of subjective visual acuity(decimal V). Objective visual acuity(VA)were distributed from 8.3+/-1.87 to 21.4+/-3.1 and showed high correlation(p<0.00 ). The relationship between the objective VA obtained from SVT and subjective VA make a regression line(y=-12.874X+21.303).Subjective VA could be obtained from conversion of objective VA with 95%confidence belt. In conclusion, the objective visual acuity with SVT is highly correlated with subjective visual acuity and SVT using the OKN response to stimuli presented on HMD by the computer program can be useful in assessing visual function objectively.