The Comparasion of the Dynamic Stereoacuity with Two-Rods Test and Three-Rods Test

Purpose: On this study, we measured and compared the dynamic stereoacuity by two-rods test (Howard-Dolman Test) and three-rods test. And we analyzed the correlation between PD and refractive error with dynamic stereoacuity. Methods: Dynamic stereoacuity of two-rods test and three-rods test at 2.5 m distance for 93 adults 93 (50 males, 43 females), mean age of $21.27{\pm}2.32$ (19~32) years old, were measured 5 times for two tests. Results: The mean of dynamic stereoacuity measured by two-rods test and three-rods test were $29.91{\pm}23.03sec$ of arc and $23.75{\pm}21.65sec$ of arc for total subjects, respectively. The mean of male and female were $36{\pm}22.38sec$ of arc and $22.28{\pm}23.79$, respectively. Three-rods test showed better dynamic stereoacuity than two-rods test, but there was no statistically significant difference (p>0.05). For the average standard deviation of PD between 60.63 mm~66.19 mm, dynamic stereoacuity fo two-rod test and three-rod test were $31.48{\pm}24.87sec$ of arc and $31.48{\pm}24.87sec$ of arc, respectively. The results showed statistically significant difference (p<0.05), but the relationship between dynamic stereoacuity and PD was not great. Comparison between two tests on the basis of refractive error, dynamic stereoacuity by three-rods test was better than by two-rods test with no significant difference between both tests (p>0.05) and there was little correlation between refractive error and two dynamic stereoacuity. Conclusions: Three-rods test showing lower stereoacuity than two-rods tests could measure the lower minimum threshold of dynamic stereoacuity. It was found that both tests can be applied to dynamic stereoacuity test as a standard test, and PD and refractive error was found that little effect upon the dynamic stereoacuity. PD and refractive error was found that little effect upon the dynamic stereoacuity.

이간계와 삼간계를 이용한 동적 입체시의 비교

목적: 본 연구는 이간계인 하워드-돌먼 입체검사와 삼간계로 성인의 동적 입체시를 측정하여 비교해 보고, PD 및 굴절이상과 동적 입체시의 상관성을 분석해 보았다. 방법: 평균연령 $21.27{\pm}2.32$(19~32)세인 성인 93명(남자50, 여자43)을 대상으로 이간계(two-rods test)와 삼간계(three-rods test)로 검사거리 2.5 m에서 동적 입체시를 각각 5회 측정하였다. 결과: 이간계와 삼간계로 측정한 동적 입체시는 각각 전체 평균 $29.91{\pm}23.03$초, $23.75{\pm}21.65$초 였고, 이중 남자는 $28.36{\pm}22.38$초, $22.28{\pm}23.79$초 여자는 $31.71{\pm}23.91$초, $25.46{\pm}19.00$초로 이간계에 비해 삼간계로 측정한 동적 입체시가 모두 좋았으나 통계적으로 유의한 차이는 없었다(p>0.05). PD 평균 표준편차 범위 60.63 mm~66.19 mm 사이의 동적 입체시는 이간계 $31.48{\pm}24.87$초, 삼간계는 $22.54{\pm}17.22초$로 통계적으로 유의한 차이가 있었으나(p<0.05), 두 검사법의 동적 입체시와 PD의 상관성은 크지 않았다. 굴절이상을 기준으로 할 때도 이간계에 비해 삼간계로 측정한 동적입체시가 모두 더 좋게 나타났으나 통계적으로 유의한 차이는 없었고(p>0.05) 굴절이상과 두 동적 입체시간의 상관성도 거의 없었다. 두 입체시는 일반적으로 정상인의 동적 입체시로 간주하는 30~50초 범위에 해당하는 결과가 나타났다. 결론: 삼간계는 이간계보다 입체시가 더 낮게 나타나 동적 입체시의 더 낮은 최소 역치를 측정할 수 있고, 두 검사법이 성인의 동적 입체시 표준검사법으로 사용되고 동적 입체시의 기준을 적용하는데 유용할 것으로 사료된다. PD와 굴절이상은 동적 입체시에 큰 영향을 주지 않는 것으로 나타났다.