Abstract
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.
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![]() | Figure 6.The objective visual acuity (horizontal) versus subjective visual acuity (vertical) in suppression method. |
![]() | Figure 7.The correlation of objective visual acuity and subjective visual acuity in suppression method. |
![]() | Figure 8.The objective visual acuity (horizontal) versus subjective visual acuity (vertical) in induction method. |
![]() | Figure 9.The correlation of objective visual acuity and subjective visual acuity in induction method. |