Presentation on theme: "Lang test, Randot test & TNO test Comparison of Lang test, Randot test & TNO test in the assessment of stereo-acuity of normal population. Authors : Shalaka."— Presentation transcript:
Lang test, Randot test & TNO test Comparison of Lang test, Randot test & TNO test in the assessment of stereo-acuity of normal population. Authors : Shalaka Paralkar, Mihir Kothari, Khushbu Shah E-Poster No. FP289 E-Poster Serial No.: 268
Disclaimer We have no Financial interest in any of the products mentioned in this poster We have not received any financial assistance to carry out this study
Introduction 1 - Czepita D, Goslawski W, Mojsa A. Occurrence of anisometropia among students ranging from 6 to 18 years of age. Klin Oczna. 2005;107(4-6):297-9. 2 - Weber, JL; Wood, Joanne : Amblyopia: Prevalence, Natural History, Functional Effects and Treatment. Clinical and Experimental Optometry 88 (6) Appropriate therapeutic measures can improve the stereoacuity in such patients.
Aim Comparison of tests Development of normative data for stereoacuity of normal population
Methods and materials Inclusion criteria Best corrected visual acuity – 6/6 Orthotropic Normal binocularity Measured Stereoacuity Using Lang test(Lang type 1 test), Randot test and TNO test: with appropriate refractive correction With appropriate environmental lighting at reading distance ( 40 cm)
Results 46 consecutive patients aged 19.3 years ± 7.2 (5-36) 26 were females. All the patients had measurable stereopsis on these tests. Mean Stereoacuity: Lang test = 550 Randot test = 50 ± 36.8 (20-250) TNO test = 60 ± 63 (15-240)
Discussion Performance on motor skills of a person is related to stereoacuity* Various methods have been used to assess stereoacuity in children. Some tests have made use of global stereopsis (TNO test,Frisby test, Lang test etc.) and some are based on local stereopsis (Titmus test, Randot test) *OConnor AR et al : The functional significance of stereopsis. Invest Ophthalmol Vis Sci. 2010 Apr;51(4):2019-23. Epub 2009 Nov 20.
Merits: Useful for screening in children. No glasses necessary OUR EXPERIENCE: Easy to perform in children Gives a general idea about presence of gross stereopsis More convenient to use in unco-operative children as there is no requirement for glasses Demerits: Only gross stereopsis with Lang 1 Lang 2 required for finer stereopsis
Merits Can detect stereoacuity over a range of 20 to 500 seconds of arc OUR EXPERIENCE Children could easily view the animal figures Effectively gave an idea of the fine stereopsis Demerits Mono-ocular clues are present
Merits Can measure stereoacuity over a range of 15 to 480 seconds of arc No mono-ocular clues OUR EXPERIENCE Easier to perform in children as compared to Randot test Demerits Crowding phenomenon may be seen Dissociation may be present