Abstract:AIM: To evaluate visual field of the unilateral visually impaired applicants by a custom program test of Humphrey perimeter, which was indispensable for car driving.
METHODS: A retrospective study was performed. The process of a custom defined Humphrey ‘1 EYE Screening' program was set covers field region from temporal 90° to nasal 60°, and over 30° vertically away from the horizontal line. The candidates were qualified eligibility by range of visual field and reliability of the results. This study conducted statistics on the applicants who fulfilled the test from July 1st, 2016 to June 30th, 2017, and compared the impact factors of the pass rate.
RESULTS: After excluding repeated measurement reports, this study included 618 subjects, the most common causes of these eyes impaired were ocular trauma(49.7%)and unhealed amblyopia(29.3%). A total of 497 candidates(80.4%)passed the test. 85 of the 121 failure cases(70.2%)were due to a limitation of the nasal visual field(less than 60°), and 12 cases were failed by fixation loss because of nystagmus or poor cooperation. Compared with the test failure group, the subjects in the passing group are older, the average correct response points is more, and the average test time is shorter, all with statistically significant differences(P<0.05). In the passing group, the proportion of subjects with equivalent spherical mirror <0.5D was 77.5%, which was significantly higher than 62.8% in the failure group(χ2=7.264, P=0.007).
CONCLUSION: The custom program ‘1 EYE Screening' of Humphrey perimetry can be used to qualify eligibility of driving for unilateral visual impaired applicants. In order to prevent peripheral interfering from eye frames, corneal contact lenses were recommended for applicants with refractive errors.
