Testing And Clinical Evaluation Of Stereopsis And Aniseikonia For Normal And Amblyopia Children

Stereopsis is one high visual acuity that is based on the binocularsimultaneous vision and binocular fusion. Stereoacuity is the minimum disparityin depth perception that can be perceived. With the development of the humancivilization, more and more fine works are needed. In terms of this condition,demanding the stereoacuity is as high as possible. At present, the recovery ofstereopsis has been taken as one standard of the heal of strabismus and amblyopiain and out the country. The deeper acquitance to the significance of stereopsis, the more stereotestsare developed. Nowadays there are many stereotest used in the clinics, such asTitmus, TNO, synoptophore random-dot stereotest made by YanShaoMing.Among all of these stereotest, random-dot stereotest is the most exact and it canreflect exactly binocular stereopsis. What's more,it has no monocular cues.Compared with other stereopsis tests, random-dot stereotest software based oncomputer designed by Xujin has many advantages, such as convenient, nicety, andso on.it can not only used in the clinical examination but also used in the clinicalresearch through regulating the parameters. It is called aniseikonia that One object can be percepted as different imagesin size and shape by two eyes.In clinic, both anisometropia and artificial lensintroplanting can induce aniseikonia. The mild aniseikonia can cause visualfatigue and the severe aniseikonia can affect stereopsis.So it is significent to doaniseikonia test in the ophthalmologic clinics and profession choice.the sameimages or the similar images can be fusioned by the visual cortex. The moredifferent in the two images, the less impossible to be fusioned. That is to say thatthe aniseikonia is more exacuity. The computer aniseikonia sofeware desigened byXujin base on the characters that cross and circularity can not be fusioned.In thetest, comparing the size of the cross and circularity with the red-green spectacle.From this, we can say that this test has advantages of simpleness, convinent andhigh veracity.Amblyopia is one kind of developing obstruction in one eye or two that iscaused by insurfficient stimulation or abnormal reciprocity of two eyes in thecritical period of development. In general, the retified visual acuity is under 0.8.Anisometropia amblyopia is one kind of common amblyopia. The mechanism ofthe effect of anisometropia amblyopia on stereopsis may be blur image in retinalor aniseikonia.In the study, we use this random-dot stereotest and aniseikonia software tomeasure the stereoacuity and aniseikonia of normal and amblyopia children.Purpose: To test and clinically evaluate the stereopsis and aniseikonia of thenormal preschool children with the software designed by Xujin.Discussing thestatus of stereopsis and aniseikonia in amblyopia children.Methods: 1.one hundred of preschool children age from 3 to 6 years oldfrom two kindergarten of our city are measured with three stereotest: software,Titmus, stereotest in synoptophore of Yan. 2.Compare the result of the threestereotest to evaluate the practicity of the software designed by Xujin. 3.Stereopsisand aniseikonia of 24 anisometropia amblyopia are tested with this software.Results: 1.The result of Titmus and software is not significent different(X2=0.1417, 0.500.05). 9. Afterfull spectacles, the average stereoacuity of anisometropia amblyopia is 273.33".The average aniseikonia is7.39%. The average stereoacuity and the averageaniseikonia in the mild amblyopia, the medium amblyopia and severe amblyopiais that: 116.67"4.72%, 285"9.41%and 720"11.37%. 10. The stereoacuity andaniseikonia of the 1D-2D anisometropia is 133.33"5.09%,that of the 2D-3Danisometropia is 280" and 7.96%, that of the higer than 3D anisometropia is800"and 12%.Conclusion: 1.The computer random-dot stereopsis and aniseikonia testsoftware is a credible and practical method that can be used in the clinics and theresearch. 2. In preschool children, the stereoacuity develop with age. 3.Aniseikonia under4.5%may not affect stereoacuity. 4. Aniseikonia don't changewith age. 5. In the anisometropia amblyopia children, the stereoacuity reduce andthe aniseikonia increase with the degree of amblyopia and anisometropia.