Influence of anisometropia on stereovision

Darbs ir uzrakstīts latviešu valodā uz 33 lapām, satur 21 attēli, 2 tabulas un 24 atsauces uz literatūras avotiem. Darba mērķis ir noteikt stereoredzes asuma izmaiņas atkarībā no anizometropijas lieluma. Darba uzdevumi. Noteikt atkarību starp anizeikoniju un anizometropiju. Noteikt regresijas veidu starp stereoredzes asumu un anizometropijas lielumu. Noteikt maksimālu anizometropijas lielumu, pie kura vēl ir iespējama stereoredze. Subjekti. Eksperimentā piedalījās 11 subjekti bez anizometropijas ar vidējo vecumu 22,3 ± 0,2 gadi un 6 subjekti ar 1,0 D līdz 2,25 D lielu anizometropiju ar vidējo vecumu 21,8 ± 0,6 gadi. Metode. Eksperimentā mākslīgi tika inducēta anizometropija ar pozitīvām lēcām un pie katra apmiglojuma mērīti redzes asums, stereoredzes asums ar TNO un Titmus testiem un anizeikonijas lielums. Anizeikonijas noteikšanai bija izstrādāts tests Microsoft Office Power Point programmā pēc NAT testa principa. Rezultāti. Stereoredzes asums gan anizometropu gan neanizometropu grupām pie nelielas redzes asuma starpības gandrīz nemainījās, bet, sākot no 0,48 neanizometropiem un 0,54 anizometropiem tas mainās strauji. Pie anizeikonijas stereoredzes asums būtiski samazinājās pie 3,0 ± 0,3 % anizometropiem un 4,3 ± 0,5 % neanizometropiem. Iegūtie rezultāti neanizometropu un anizometropu grupām statistiski nenozīmīgi atšķiras, bet tomēr anizometropiem visos eksperimentos rezultāti bija nedaudz labāki, jo tie ir vairāk toleranti pret anizometropiju. Kā arī viņiem stereoredze saglabājas ilgāk, palielinot apmiglojumu, nekā neanizometropiem. Secinājumi. 1.Katra 1,0 D briļļu korekcija izraisa 1,1 ± 0,1 % anizeikoniju. Tas nozīmē, ka starp anizometropiju un anizeikoniju pastāv lineāra atkarība un šo likumu var klīniski pielietot anizeikonijas noteikšanai. 2.Starp anizometropiju un stereoredzes asumu pastāv eksponenciāla atkarība. No 1,0 D anizometropijas katrs nākamais 0,5 D apmiglojums nozīmīgi pasliktina stereoredzes asumu. 3.Maksimālais anizometropijas lielums, pie kura vēl ir iespējama stereoredze anizometropu grupai sastāda 3,9 ± 0,1 D un neanizometropu grupai 4,7 ± 0,1 D Atslēgas vārdi: stereoredzes asums, anizeikonija, anizometropijaBachelor work is written in Latvian on 33 pages. It contains of 21 pictures, 2 tables and 24 references. Aim. To determine stereoacuity changes depending on a size of anisometropia. Task. To estimate correlation type between aniseikonia and anisometropia. To estimate regression type between stereoacuity and size of anisometropia. To find maximal value of anisometropia still maintaining stereovision. Subjects. In experiments, there participated 11 subjects without anisometropia, average age 22.3 ± 0.2 years, and 6 subjects with 1.0 D to 2.25 D anisometropia, average age 21.8 ± 0.6 years. Method. Anisometropia was induced with positive lenses. After each blurring, there was measured visual acuity, stereoacuity with TNO and Titmus tests and aniseikonia. Aniseikonia test was created in the Microsoft Office Power Point program using principles of NAT test. Results. Stereoacuity almost did not change in anisometrope and non-anisometrope groups of when visual acuity difference was small, but changed rapidly at visual acuity difference of 0.48 for non-anisometropes and 0.54 for anisometropes. Stereoacuity diminished substantially when aniseikonia reached 3.0 ± 0.3 % for non-anisometropes and 4.3 ± 0.5 % for anisometropes. The was no statistically significant difference between results for anisometropes and non-anisometropes, but, however, anisometropes showed a little bit better results because they are more tolerant to anisometropia. Their stereovision was kept longer with increasing blurring unlike in non-anisometropes. Conclusions. 1.1.0 D of anisometropia produces of 1.1 ± 0.1 % of aniseikonia. That means that there is a linear correlation between anisometropia and aniseikonia and this law can be clinically applied determining the size of aniseikonia. 2.There is exponential correlation between anisometropia and stereoacuity. Starting from 1,0 D of anisometropia every next blurring (0,5 D large) considerable deteriorate stereoacuity. 3.The maximal value of anisometropia still allowing stereovision is 3.9 ± 0.1 D in group of anisometropes and 4.7 ± 0.1 D in group of non-anisometropes. Key words: stereoacuity, aniseikonia, anisometropi