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.
Child, Preschool ; Diagnosis, Computer-Assisted/*methods ; Female ; Humans ; Infant ; Male ; Prospective Studies ; Vision Disorders/*diagnosis ; Vision Tests/*methods ; *Visual Acuity

This paper outlines kinds of index of eyes' optical effect and some different testing methods of intraocular lenses' optical quality.
Humans ; Lens Implantation, Intraocular ; Lenses, Intraocular ; Refractometry ; methods ; Sensitivity and Specificity ; Vision Tests ; methods

OBJECTIVE: To establish an acuity inspection system with sweep pattern visual evoked potential (SPVEP) so as to provide the evidence for acuity objective inspection. METHODS: Based on the domestic sweep pattern visual evoked apparatus, sections of hardware were reformed and a manipulation program possessing false random control software was compiled. The SPVEP acuity for the 78 eyes (10 normal eyes, 10 ametropia eyes, 48 prevalence eyes, 10 false ametropia eyes) was estimated with our acuity objective inspection system, then compared with the E visual acuity of those eyes by statistical procedure. RESULTS: There was a close correlation between the SPVEP acuity and E visual acuity for 78 eyes (r2 = 0.946). CONCLUSION SPVEP acuity inspection system can be applied to estimate objective acuity.
Evoked Potentials, Visual/physiology* ; Forensic Medicine/methods* ; Humans ; Vision Tests/methods* ; Visual Acuity/physiology*

OBJECTIVE: To investigate the changes of sweep pattern visual evoked response (SPVER) acuity in different temporal frequency. METHODS: The persons were collected and divided into the low visual acuity group (71 eyes) and the high visual acuity group (92 eyes). The eyes were stimulated with different temporal frequency (8.5 Hz, 10 Hz, 15 Hz and 20 Hz, respectively) and the same series of spatial frequency. The accuracy of SPVER acuity in different temporal frequency was evaluated by compare the SPVER acuity with the subjective vision. RESULTS: In the low visual acuity group, there was a good correlation between the SPVER acuity and the subjective vision applying the spatial frequency of the group. In the high visual acuity group, the SPVER acuity was lower than the subjective vision. SPVER acuity showed a good correlation with the subjective vision at the temporal frequency of 10 Hz in two groups. CONCLUSION The temporal frequency can influence SPVER accuracy, so it is necessary to select the suitable stimulation condition in forensic practice.
Adult ; Evoked Potentials, Visual/physiology* ; Female ; Forensic Medicine/methods* ; Humans ; Male ; Photic Stimulation/methods* ; Time Factors ; Vision Disorders/physiopathology* ; Vision Tests/methods* ; Visual Acuity/physiology* ; Young Adult

This review summarizes objective assessment of visual function using visual electrophysiology. Objective assessment of visual acuity using pattern visual evoked potential (PVEP) and sweep pattern visual evoked potential (SPVEP), objective assessment of visual field using multifocal visual evoked potential (MVEP).
Electrophysiology ; Evoked Potentials, Visual ; Humans ; Photic Stimulation ; Vision Tests/methods* ; Vision, Ocular/physiology* ; Visual Acuity/physiology* ; Visual Field Tests ; Visual Pathways/physiology*

OBJECTIVETo test the effects of corrective spectacles in hyperopic amblyopic children with heterophoria.

METHODSVisual acuity, refraction and the amount of heterophoria on near (33 cm) fixation were measured before and after 3 weeks of spectacle-wearing in 30 hyperopic amblyopic children with heterophoria. The control group consisted of 20 emmetropic children age-matched to the patients.

RESULTSUncorrected eyes displayed hyperopic amblyopia accompanied by heterophoria. Corrective spectacles not only attenuated the hyperopia and amblyopia, but also changed the heterophoria to orthophoria. The amount of heterophoria before wearing spectacles was significantly different from that in emmetropic children; but after correction with spectacles, it was the same as that in the emmetropic controls.

CONCLUSIONCorrection with spectacles is effective for the treatment of heterophoria in hyperopic children with amblyopia.

Accommodation, Ocular ; Amblyopia ; diagnosis ; therapy ; Child ; Eyeglasses ; Humans ; Hyperopia ; diagnosis ; therapy ; Refraction, Ocular ; Vision Tests ; methods

INTRODUCTIONThe aim of the study was to compare the visual performance of LASIK eyes measured using high-contrast logMAR letter charts under bright (photopic) and dim (mesopic) conditions.

MATERIALS AND METHODSA total of 46 subjects (35 +/- 8 years of age) undergoing LASIK procedures were recruited for the study. The best spectacle-corrected visual acuity (BSCVA) of each subject was measured using the high-contrast ETDRS logMAR chart under photopic and mesopic conditions at 3 visits: preoperative (Pre), 1 month postoperative (Post1) and 3 months postoperative (Post3). The differences in logMAR scores for the right eyes only were analysed for the Pre-Post1 (n = 46), Pre-Post3 (n = 18) and Post1-Post3 (n = 16) comparisons.

RESULTSThe logMAR scores of subjects were worse at the 1-month postoperative visit than preoperatively, and improvement in visual performance was seen at the 3-month postoperative visit. These changes in visual performance became more evident under mesopic conditions. The means and standard errors of the differences in logMAR scores for the Pre-Post3 (0.097 +/- 0.020) were slightly larger than those of the Pre-Post1 (-0.067 +/- 0.019) and Post1-Post3 (0.031 +/- 0.012) comparisons. Under mesopic conditions, the visual performance of the subjects was statistically significant for the 3 comparisons, but not under photopic conditions.

CONCLUSIONHigh-contrast logMAR chart performed under mesopic conditions has the potential to replace visual acuity measured under photopic conditions in providing more reliable representation of postoperative visual outcomes of LASIK eyes. Eye doctors should consider performing this vision test routinely to gauge the success of LASIK surgery.

Adult ; Contrast Sensitivity ; Female ; Humans ; Keratomileusis, Laser In Situ ; adverse effects ; Lighting ; Male ; Middle Aged ; Reproducibility of Results ; Vision Disorders ; diagnosis ; etiology ; Vision Tests ; methods ; Visual Acuity

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.
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*

To evaluate its clinical efficacy, we report the results of Armaly central field screening test in comparison with those of central 30-2 threshold test of Humphrey Field Analyzer. In 83 cases of normotensives, ocular hypertensives, and glaucoma patients with open-angle or narrow-angle enrolled in this study, a total of 143 eyes were examined. Fifty-four out of 61 patients (88.5%) and 73 out of 81 eyes (90.1%) with visual field defects were detected by the Humphrey Field Analyzer screening test. Eight eyes out of 81(9.9%) with visual field defects detected by the screening test were confirmed as false positive. All points of false positive were solitary, which tended to occur more frequently on superior visual field. A false negative of eight eyes out of 62 (12.9%) detected by the screening test was confirmed by the threshold test, which was more frequent on superior field and shown to be located more peripherally from the fixation point. There was no significant difference in either central sensitivity or age of the false positive and negative.
Adult ; Aged ; Evaluation Studies as Topic ; Female ; Glaucoma/*physiopathology ; Humans ; Male ; Middle Aged ; Ocular Hypertension/*physiopathology ; Predictive Value of Tests ; Vision Screening/*methods ; Visual Field Tests/*methods ; *Visual Fields

Existing methods of stereoacuity testing need specific glasses or optical device for use. We have designed a new stereoacuity test for the digitalized, random-dot stereogram and researched its clinical usefulness. A digitalized, random-dot, stereoacuity test card was created with a computer program that used a preferred symbol and the designed system was tested along with the Randot preschool stereoacuity, Titmus-fly and Lang tests to compare their sensitivity and specificity. The mean success rate of the digitalized, random-dot test was 98.2%, while the rates of the Randot preschool stereoacuity, Titmus-fly and Lang tests were 89.3%, 74.2% and 86.1%, respectively. Sensitivity and specificity of the new test were 100% and 95.3%, respectively, which were not that different from those of the Randot preschool stereoacuity, Titmus-fly and Lang tests. We found that the digitalized, random-dot, stereoacuity test has a high success rate and can be appropriately used in medical examinations and follow-up tests for strabismus patients.
Age Distribution ; Child, Preschool ; Comparative Study ; Computer Graphics ; Depth Perception/*physiology ; Female ; Humans ; Male ; Reproducibility of Results ; Research Support, Non-U.S. Gov't ; Sensitivity and Specificity ; Software ; Vision Disorders/*diagnosis ; Vision Tests/*instrumentation/methods ; Vision, Binocular