• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.385-390
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• 2015

Purpose: This study evaluated the static stereoacuity by Distance Randot Stereotest (STEREO OPTICAL. Co., Inc. USA) and the dynamic stereoacuity by three-rods test (iNT, Korea). Criterion and correlation of stereoacuity between both tests and usefulness of two stereotest methods were also evaluated. Methods: For normal adults of 109 (male 61, female 48), mean age of 20.88 (19-32 years) years old, static stereoacuity by using Distance Randot Stereotest at 3 m distance, dynamic stereoacuity by using three-rods test at 2.5 m distance were measured. Results: The mean of distance static stereoacuity was $155.77{\pm}133.11sec$ of arc and the mean of error distance dynamic stereoacuity $11.13{\pm}9.69mm$. With equivalent-conversion stereoacuity of $23.44{\pm}20.96sec$ of arc, there was statistically significant differences (p=0.00) between two dynamic stereoacuity, but correlation was relatively low (${\rho}=0.226$). In the case of dynamic stereoacuity, separated to normal range by criterion of the error distance 20 mm, it showed the error distance of less than 20 mm in 97 subjects(89%) whose average of error distance and conversion mean dynamic stereoacuity were $8.43{\pm}5.10mm$ and $17.68{\pm}10.67sec$ of arc. repectively. The error distance of was equivalent-conversion dynamic stereoacuity 40.99 sec of arc (PD 62 mm basis) was 20 mm. Conclusions: The results of lower correlation between static and dynamic stereoacuity suggest that seterotest should be applied separately to different functions. The results of this study also suggest that Distance Randot Stereotest can be applied to static stereoacuity excluding monocular cues. Three-rods test can be applied to dynamic stereoacuity containing the response of the eye-hand coordination in the daily life of natural vision condition, including the monocular cues. These different approaches canprovide a criterion of the two stereoacuity and parallel use of the two tests would be useful. For dynamic stereoacuity by three-rods test, error distance 20 mm in a normal range of adults can be used as a criteria to get statistical meaning of the results.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.1
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• pp.67-73
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• 2015

Purpose: This study was investigated the relationship between the male and female of near stereoacuity and phoria, and was examined the correlations between near stereoacuity and phoria and refractive error. Methods: Adult 83 (male 36, female 47, mean age $21.09{\pm}1.74$(19~29) years old) target was examined after full correction of refractive error. Near stereoacuity was measured by using Titmus-fly Stereotest(Stereo Optical Co., Inc., Chicago, IL, USA), and RANDOT Stereotest (Stereo Optical Co., Inc., Chicago, IL, USA), phoria was measured by using modified torrington method, at distance 40 cm. Results: In near stereoacuity, male was better good than female, and there was no difference between male and female (p>0.05). In near phoria, female was more higher than male, and there was a significant difference between male and female (p<0.05). Near stereoacuity by Titmus-fly test and Randot test result respectively was $262.17{\pm}562.43$ sec (second of arc) $243.08{\pm}68.04$ sec in esophoria, $148.42{\pm}269.54$ sec, $107.40{\pm}263.74$ sec in orthophoria, $113.94{\pm}152.46$ sec, $79.70{\pm}136.83$ sec in exophoria, there was a no difference between three phoria groups (p>0.05), and was a high correlation between phoria and near stereoacity(r=0.68). In addition, near stereoacuity in the refractive error respectively was $80.00{\pm}571.43$ sec, $68.75{\pm}36.82$ sec in myopia, $133.57{\pm}224.15$ sec, $93.14{\pm}214.95$ sec in hyperopia, $511.20{\pm}855.00$ sec, $511.4{\pm}855.60$ sec, there was a significant difference between three phoria groups (p<0.05). when was classfiied near stersoacuity into degree of refractive error, near stersoacuity was best in emmetropia, and was reduced when refractive error was highest in high degree myopia, and hyperopia. Conclusions: Titmus-fly Stereotest and RANDOT Stereotest result, near stereoacuity of adults, when esophoria and high degree refractive error, was reduced, there was a relationship between near stereoacuity with phoria, and refractive error. In this both stereotests if was bad when near stereoacuity can expect a phoria and refractive error.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.3
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• pp.321-327
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• 2013

Purpose: To investigate a correlation between vertical fixation disparity and stereopsis by analyzing distribution of types of vertical fixation disparity. Methods: In this study, RANDOT(R) stereotest partly using random dot was used in stereopsis tests. The vertical fixation disparity in close proximity categorized fixation disparity slope into six types on the basis of the result of measurement in when two thin lines, one for one eye looks, become overlapped as a line by adding into prism with Wesson fixation disparity card while maintaining a distance of 25 cm from patients. Results: In the types of near vertical fixation disparity curve, targeting 43 people, the first type 55.82% was the most distributed, the second type is the least 23.25%, the third type of 4.65%, the fourth type of 4.65%, the fifth type of 6.98%, the sixths types of 4.65% were distributed. The result of a correlation analysis, which shows the degree of linear correlation between two variables, represented that stereopsis is not correlated with Y-intercept (r = -0.07) which show vertical fixation disparity, associated phoria (r = -0.03) and dissociated phoria (r = -0.00), but it was not statistically significant (p>0.05). Fixation disparity slope of vertical fixation disparity (r = 0.36) was shown to have a positive correlation with stereopsis. It has a low positive correlation and a meaningful statistics (p<0.05). The Y-intercept which indicates vertical fixation disparity was also not associated with stereopsis (r = -0.07) and dissociated phoria (r = -0.03), and this was not statistically significant (p>0.05), while it had a high correlation as well as a statistically significant with associated phoria (r = 0.89). There was a negative correlation between Y-intercept and fixation disparity slope of vertical fixation disparity (r = -0.33). It showed a low relationship but statistically valuable (p>0.05). As a result of regression analysis, the stereopsis was changed as 7.631" if vertical fixation disparity changes 1' and the vertical fixation disparity changed as 0.017' if stereopsis changes 1', and the change was statistically significant (p<0.05). Conclusions: The study shows that there is a low correlation between stereopsis and vertical fixation disparity, and it is difficult to determine stereopsis only using vertical fixation disparity. Therefore, it suggests other factors above vertical fixation disparity have greater influence on stereopsis.