Background:Dyop®is a dynamic optotype with a rotating and segmented visual stimulus.It can be used for visual acuity and refractive error measurement.The objective of the study was to compare refractive error mea...Background:Dyop®is a dynamic optotype with a rotating and segmented visual stimulus.It can be used for visual acuity and refractive error measurement.The objective of the study was to compare refractive error measurement using the Dyop®acuity and LogMAR E charts.Methods:Fifty subjects aged 18 or above with aided visual acuity better than 6/12 were recruited.Refractive error was measured by subjective refraction methods using the Dyop®acuity chart and LogMAR E charts and the duration of measurement compared.Thibo’s notation was used to represent the refractive error obtained for analysis.Results:There was no significant difference in terms of spherical equivalent(M)(P=0.96)or J0(P=0.78)and J45(P=0.51)components measured using the Dyop®acuity and LogMAR E charts.However,subjective refraction measurement was significantly faster using the Dyop®acuity chart(t=4.46,P<0.05),with an average measurement time of 419.90±91.17 versus 452.04±74.71 seconds using the LogMAR E chart.Conclusions:Accuracy of refractive error measurement using a Dyop®chart was comparable with use of a LogMAR E chart.The dynamic optotype Dyop®could be considered as an alternative fixation target to be used in subjective refraction.展开更多
基金the Human Subjects Ethics Committee of The Hong Kong Polytechnic University(No.HSEARS20170215006)the study was conducted in accordance with the Declaration of Helsinki(as revised in 2013).
文摘Background:Dyop®is a dynamic optotype with a rotating and segmented visual stimulus.It can be used for visual acuity and refractive error measurement.The objective of the study was to compare refractive error measurement using the Dyop®acuity and LogMAR E charts.Methods:Fifty subjects aged 18 or above with aided visual acuity better than 6/12 were recruited.Refractive error was measured by subjective refraction methods using the Dyop®acuity chart and LogMAR E charts and the duration of measurement compared.Thibo’s notation was used to represent the refractive error obtained for analysis.Results:There was no significant difference in terms of spherical equivalent(M)(P=0.96)or J0(P=0.78)and J45(P=0.51)components measured using the Dyop®acuity and LogMAR E charts.However,subjective refraction measurement was significantly faster using the Dyop®acuity chart(t=4.46,P<0.05),with an average measurement time of 419.90±91.17 versus 452.04±74.71 seconds using the LogMAR E chart.Conclusions:Accuracy of refractive error measurement using a Dyop®chart was comparable with use of a LogMAR E chart.The dynamic optotype Dyop®could be considered as an alternative fixation target to be used in subjective refraction.
