CC BY
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DOI 10.31718/2077-1096.22.1.25 UDC 617.753 Hasanzade L. Yu
EVALUATION OF STEREOVISION FINDINGS USING THE TITMUS TEST IN CHILDREN AND ADOLESCENTS WITH REFRACTIVE ERRORS
Azerbaijan State Institute of Advanced Medical Training named after A. Aliyev, Baku, Azerbaijan
The purpose of the study: to evaluate the indicators of stereovision using the Titmus test for an accurate assessment of stereovision and its correction in children and adolescents. Materials and methods. The study was carried out in 143 patients (286 eyes), including 73 girls (51.0%) and 70 boys (49.9 %). The participants were divided into two groups: the first group involved 6 children with myopia and 11 children with hypermetropia; the second group included 126 people with astigmatism. The second group with astigmatism (252 eyes) included 24 children with myopic astigmatism (19.04 %), 92 children with hypermetropic astigmatism (73.01 %) and 10 people (7.93 %) with mixed astigmatism. All patients of the two groups underwent advanced testing of visual functions that involved a series of the following procedures: visiometry with distance correction, autorefractometry (assessment of spherical refraction and astigmatism using an autorefractometer) before and after cycloplegia, assessment of binocular vision by four-point color test, Worthtest test, (assessment of the nature of vision), heterophoria measurements (cover test), ophthalmoscopy with a dilated pupil (diagnosis of the retina and optic nerve). Results. All 143 patients (286 eyes) were examined by using the Titmus test. The findings obtained showed that gross changes were observed in 14 (5.6 %) patients with astigmatism in the first group and pronounced changes were found in 81 (45.0 %) patients with hypermetropic astigmatism in the second subgroup. In this study, the Titmus test was carried out at medium distances that should be taken into account when assessing stereovision by graded tests. Conclusion. The use of the Titmus test can significantly improve the accuracy of measuring stereovision indicators; it makes screening procedures more comfortable and increases the effectiveness of timely diagnosis of binocular vision disorders. Screening examination of stereovision is promising, as it will significantly improve the quality of screening diagnostics of stereoscopic perception.
Key words: Titmus test, children, diagnostics, screening, stereovision.
This work is a part of ongoing PhD dissertation in medicine "The effectiveness of early diagnosis of pediatric refraction disorder by the device "Plusoptix A- 09" and "Titmus" test."
Introduction
Stereovision is the ability to perceive the external environment as a space filled with three-dimensional objects located at different distances from the eyes and from each other. A large number of works have been devoted to the study of human stereovision related to such fields of science as theoretical and clinical ophthalmology, neurophysiology, physiological optics, etc. [1-4]. It is known that the basic mechanisms of stereovision start working in humans in very early age, nearly in the first months of life and develop rapidly [5-7].
Therefore, the state of stereovision in children should be monitored from an early childhood using a whole set of tests to assess the functioning of different parallel channels. There are many tests used to evaluate stereovision. And one of the important tasks is to choose the most adequate methodology and optimal test parameters for measurements and tests that will ensure the availability of stereovision assessment in children and adults [2, 7-9]. The task of optimizing measurement procedures is to create convenient and effective diagnostic tools and functional correction of stereovision disorders (in particular, correction of ametropia, treatment of amblyopia and strabismus), which are detected by vision testing.
The purpose of the study is to evaluate the indicators of stereovision using the Titmus test for an accurate assessment of stereovision and its correction in children and adolescents.
Materials and methods
The study involved 143 patients (286 eyes): 73 girls (51.0%) and 70 boys (49.9 %). The participants were divided into two groups: the first group involved 6 children with myopia and 11 children with hypermetropia; the second group included 126 people with astigmatism. The second group with astigmatism (252 eyes) included 24 people with myopic astigmatism (19.04 %), 92 children with hypermetropic astigmatism (73.01 %) and 10 people (7.93 %) with mixed astigmatism.
All patients of the two groups underwent advanced testing of visual functions, which included the following procedures: visiometry with distance correction, autorefractometry (assessment of spherical refraction and astigmatism using an autorefractometer) before and after cycloplegia, assessment of binocular vision by a four-point color test, the Worth test, ophthalmoscopy with a wide pupil to diagnose the state of the retina and optic nerve. The participants were patients of the paediatric department of the Academician Zarifa Aliyeva National Center of Ophthalmology.
All 143 patients (286 eyes) were examined by the Titmus test. In all subjects, visual acuity and the nature of vision were assessed by a four-point color test and binocular vision by the Titmus stereotest (at a distance of 30 cm). The groups of patients with ametropia without binocular disorders having passed the test demonstrated findings within conditional reference ranges; while the group of
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ametropes with strabismus coped worse with the task. In the group with strabismus, many children were unable to recognize certain stimuli of the Titmus test. According to the findings of the nature of vision, most children were found to have orthophoria (binocular nature of vision); the Titmus stereotest revealed that stereoscopic vision was absent in 14 patients. It should be noted that binocular perception may deteriorate with various ametropias (the results in the group with ametropia was worse than the results in the group with emmetropes).
The Titmus test, or Stereo Fly Acuity test, is the most popular and accessible test of stereo acuity worldwide; it is considered a standard diagnostic technique for measuring depth of visual perception. The test is based on horizontal retinal disparity of two images and the identification of a shape that is apparently closer. The Titmus test is a two-page booklet with various stimuli at different angles of disparity. The standard set includes: a "Fly" test for the presence or absence of stereopsis; a graded test of nine stimuli with four Wirt circles arranged crosswise (disparity range from 800 to 40); a graded test with images of animals (three rows of five figures) for young children (disparity range from 400 to 100); polaroid stereo glasses. The first test is intended for indicative identification of the presence or absence of stereoscopic mechanisms in a child. It is assessed as normal, when putting on stereo glasses, the fly depicted strongly protrudes above the surface of the leaf. The standard task given to the subject is to take hold of the wing with the fingers. If the subject put his fingers not above the sheet, but on the image plane, it points out the problems with stereovision. The second and third tests make it possible to measure the thresholds of stereo perception with certain accuracy by the ability to accurately indicate a figure protruding from the plane. This test is designed for children from 3 months to 12 years old.
Parameters
The Titmus test is a three-dimensional polaroid vectograph in the form of a booklet consisting of two tables viewed by the patient through polaroid glasses. On the right side of the booklet there is a large fly, on the left there are circles and animals. The recommended distance to carry out this test is 405 mm.
1. "Fly" is a test for rough stereopsis (3000 arc seconds), and especially informative for young children. The fly should look voluminous, and a child is offered to "lift" it by one of the wings. In the absence of a rough stereopsis, the fly looks flat, as in the photo (if you turn the booklet over, the image becomes flat). If the patient insists that the wings of the fly protrude, the stereoscopic vision assessment is incorrect.
2. "Wirt Circles" are a series of step tests to assess stereo vision. Each of the V squares consists of 4 circles. Each of the circles has a certain degree of disparity and, with normal stereopsis, protrudes over the plane. Stereoscopic visual acuity is calculated according to the table attached to the test. The disparity angle ranges from 800 to 40 arc seconds. If the patient sees a shift of the circle to the side, he does not have stereoscopic vision, but is oriented monocularly.
3. "Animals" test is similar to the test with circles and consists of 3 lines of animals, one of which protrudes over the plane. The degree of misperception ranges from 400 to 100 arc seconds.
Results and discussion
According to the data obtained, in the first group, strabismus was less than 15° in 17 people with astigmatism, strabismus angle of 15-29° was detected in 7 children (31.8%) with hypermetropic refraction and in 83 children (29.2%) with astigmatism. It should be noted that an angle of strabismus equal to or greater than 30° was detected in 10 patients (3.5%) with astigmatism (Table 1).
Table 1
ie angle of strabismus in patients of the first group with ametropia
Strabismus Myopia Hypermetropia Astigmatism x2 P
N % N % N %
Not detected 12 00 15 68,2 74 61,3
< 15° 0 0,0 0 0,0 17 6,0
15 -29° 0 0,0 7 31,8 83 29,2 9,636 0,141
>30° 0 0,0 0 0,0 10 3,5
Table 2
Parameters of the angle of strabismus in patients of the second subgroup with ametropia
Strabismus Myopic astigmatism Hypermetropic astigmatism Mixed astigmatism x2 P
N % N % N %
Not detected 43 87,8 112 55,4 9 57,6
< 15° 3 6,1 11 5,4 3 9,1
15 -29° 3 6,1 71 35,1 9 27,3 21,291 0,002
>30° 0 0,0 8 4,0 2 6,1
According to the data obtained in the second subgroup, 3 childern (6.1%) with myopic astigmatism, 11 children (5.4%) with hypermetropic astigmatism and 3 children (9.1%) with mixed astigmatism, had the angle of strabismus less than
15°; the angle of strabismus 15-29° was detected in 3 patients (6.1%) with myopic astigmatism, in 71 children (35.1%) with hypermetropic astigmatism and in 9 children (27.3%) with mixed astigmatism. An angle of strabismus equal to or greater than 30°
was detected in 8 children (4.0%) and in 2 children (6.1%) with mixed astigmatism (Table 2).
Thus, in the first group, the angle of strabismus 15 -29° was most often observed in patients with astigmatism - 83 patients (29.2%), and in the second subgroup, the angle of strabismus 15 -29° was most often observed in patients with hypermetropic astigmatism - 71 children (35.1%).
The obtained data on the binocular test in group 1 patients showed that binocular vision was observed in 12 patients with myopic refraction, in 12 (54.5%) with hypermetropic refraction and in 142 (56.3%) children with mixed astigmatism.
Monocular vision was detected in 10 children (45.5%) with hypermetropia and 110 people (43.7%) with mixed astigmatism (Table 3).
Table 3
Indicators of the binocular test in patients of the first group
Myopia Hypermetropia Mixed astigmatism x2 Р
Worth test N % N % N %
Binocular Vision 12 СС 12 54,5 142 56,3 С,С82 С,С11
Monocular vision С С,С 1С 45,5 11С 43,7
Table 4
Binocular test indicators in patients of the second subgroup
Worth test Myopic astigmatism Hypermetro pic astigmatism Mixed astigmatism x2 Р
N % N % N % 16,139 <С,СС1
Binocular vision 38 8С,9 88 48,9 6 4,С
Monocular vision 9 19,1 92 51,1 9 36,С
The obtained data on the binocular test in the patients of the 2nd subgroup showed that binocular vision was found in 38 patients (80.9%) with myopic refraction, in 88 people (48.9%) with hypermetropic refraction and in 16 children (64.0%) with mixed astigmatism.
Monocular vision was detected in 9 children (19.1%) with myopia, in 92 (51.1%) patients with hypermetropia and in 9 children (36.0) with mixed astigmatism (Table 4).
According to the data obtained in patients of the first group, normal indicators were obtained in 12 patients (100%) with myopic refraction, in 12
children (54.5%) with hypermetropic refraction and in 142 people (56.3%) with astigmatism. Pronounced changes were found in 10 patients (45.5%) with hypermetropia and in 96 children (38.1%) with astigmatism. Gross impairment of stereovision was detected only in 14 children (5.6%) with astigmatism (Table 5).
The findings described above point out that in the first group monocular vision was detected in 110 patients (43.7%) with mixed astigmatism, and in the second subgroup monocular vision was observed in 92 children (51.1%).
Table 5
of stereoscopic vision in patients of the first group with ametropia
Titmus test Myopia Hypermetropia Astigmatism x2 Р
N % N % N %
Norm 12 СС 12 54,5 42 56,3
Pronounced changes С С,С 1С 45,5 96 38,1 1С,637 С,С31
Rough changes С С,С С С,С 14 5,6
Table 6
Indicators of stereoscopic vision in the patients of the second subgroup with ametropia
Titmus test Myopic astigmatism Hypermetropic astigmatism Mixed astigmatism x2 Р
N % N % N %
Norm 38 8С,9 88 48,9 16 64,С
Pronounced changes 9 19,1 81 45,С 6 24,С 19,619 С,СС1
Rough changes С С,С 11 6,1 3 12,С
It should be noted that normal indicators of stereoscopic vision were detected in 38 children (80.9 %) with myopic astigmatism, in 88 children (48.9%) and in 16 patients (64.0 %). Pronounced changes were found in 9 children (19.1%) with myopic astigmatism, in 81 children (45.0%) with hypermetropic astigmatism and in 6 people (24.0 %) with mixed astigmatism. Gross violations were detected only in 11 children (6.1%) with hypermetropic astigmatism and in 3 patients (12.0 %) with mixed astigmatism (Table 6).
The Titmus test findings showed that gross
changes were observed in 14 (5.6%) patients with astigmatism in the first group, and in 81 (45.0%) children with hypermetropic astigmatism in the second subgroup.
In this study, the Titmus test was carried out at medium distances. This should be taken into account when assessing stereovision using graded tests. In addition, the test contained certain stimuli (depending on the modification of the test) with different disparity values that enabled to identify a graded assessment of violations. It has been shown that the Titmus test with disparity values from 3
angles. min can be quite reliable in diagnosis of binocular disorders, the results of such tests are consistent with generally accepted diagnostic tests (four-point test, etc.) [1, 5].
The Titmus test can be very helpful in conducting fast screening examinations to detect the impariment of the mechanisms of binocular stereovision. The results obtained demonstrate the prospects of implementing this test in routine research check-up for functional testing of binocular vision [1].
Conclusions
Overall conclusions show that the Titmus test is reliable and valid, and can be used to improve the accuracy of measuring stereovision, make screening procedures more comfortable and enhance the effectiveness of timely diagnosis of binocular vision disorders. Screening examination of stereospecies is promising as it will significantly improve the quality of eye health monitoring.
Prospects for further research imply the development of methods for correcting the most common functional disorders.
Реферат
ОЦ1НКА РЕЗУЛЬТАТА ПОКАЗНИК1В СТЕРЕОЗОРУ ЗА ДОПОМОГОЮ TITMUS ТЕСТА У Д1ТЕЙ I П1ДЛ1ТК1В З АНОМАЛ1ЯМИ
РЕФРАКЦИ
Гасанзаде Л. Ю.
Ключовi слова: Titmus тест, дiагностика, скрижнг, CTepeo3ip.
Мета дослщження: оцшити показники стереоскошчного зору за допомогою Titmus тесту для точно!' оцшки стереоскошчного зору та його корекцп у д1тей та пщл™в. Об'ект та методи. У дослщження включили 143 пац1енти (286 очей), з них 73 д1вчинки (51,0%) та 70 хлопчик1в (49,9%). Пац1енти були подтеы на 2 групи. Першу групу склали пац1енти з мюшею (6 д1тей), г1перметроп1ею (11 дитини). Другу групу з1 126 ос1б склали д1ти з астигматизмом: мюшчним астигматизмом (24 дитини (19,04%)), пперме-троп1чним астигматизмом (92 дитини (73,01%)), та 10 д1тей (7,93%) з1 зм1шаним астигматизмом. Ус1 пац1енти обох груп пройшли розширену д1агностику зорових функц1й, яка включала так1 процедури: вь зометр1ю з корекц1ею для дал1, авторефрактометр1ю (оц1нка сферичноТ рефракци' та астигматизму за допомогою авторефрактометра) до i п1сля циклоплегп, оц1нка б1нокулярного зору за чотириточковим кольоротестом - тест Уорса, (оцшка характеру зору - дослщження гетерофори (cover test), офтальмо-скопiя з широкою зшицею (дiагностика стану атшки та зорового нерва). Результати. Уам 143 хворим (286 очей) провели дослщження за допомогою Titmus тесту. Отриман результати Titmus теста показали, що суттeвi змши спостер^алися у 14 (5,6%) пацieнтiв з астигматизмом у першш групi, та вираже-нi змiни з пперметрошчним астигматизмом у 81 (45,0%) патента другоТ пiдгрупи. У цьому дослщжены тестування проводилися з допомогою Titmus тесту на середшх вiдстанях. Це слщ враховувати пiд час проведення оцшки стереозору за допомогою градуальних теспв. Висновки. Застосування Titmus тесту дозволяе суттево пщвищити точнють вимiрювання показникiв стереозору, зробити скринiнговi процедури комфортшшими, та збiльшити ефективнють своечасноТ дiагностики порушень бiнокулярного зору. Скриншгове дослiдження стереозору перспективне, осктьки дозволить суттево пiдвищити якють скринiнговоï дiагностики стереоскопiчного сприйняття.
Реферат
ОЦЕНКА РЕЗУЛЬТАТОВ ПОКАЗАТЕЛЕЙ СТЕРЕОЗРЕНИЯ ПРИ ПОМОЩИ TITMUS ТЕСТА У ДЕТЕЙ И ПОДРОСТКОВ С АНОМАЛИЯМИ РЕФРАКЦИИ Гасанзаде Л. Ю.
Ключевые слова: Titmus тест, диагностика, скрининг, стереозрение.
Цель исследования: оценить показатели стереозрения с помощью Titmus теста для точной оценки стереозрения и его коррекции у детей и подростков. Объект и методы. В исследовании приняли участие 143 пациента (286 глаз), из которых девочки составили 73 человека (51,0%) и мальчики - 70 человек (49,9 %) Первую группу составили пациенты с миопией (6 детей), гиперметропией (11 детей). Вторую группу с астигматизмом из 126 человек (252 глаза) составили дети: с миопическим астигматизмом 24 человек (19,04%), гиперметропическим астигматизмом - 92 детей (73,01%) и 10 человек (7,93 %) со смешанным астигматизмом. Все пациенты из двух групп прошли расширенную диагностику зри-
References
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тельных функций, которая включала следующие процедуры: визометрию с коррекцией для дали, авторефрактометрию (оценка сферической рефракции и астигматизма при помощи авторефрактометра) до и после циклоплегии, оценка бинокулярного зрения по четырехточечному цветотесту - тест Уо-рса (Worthtest), (оценка характера зрения - исследование гетерофории (cover test), офтальмоскопия с широким зрачком (диагностика состояния сетчатки и зрительного нерва). Результаты. Всем 143 больным (286 глаз) провели исследование с помощью Titmus теста. Полученные результаты показали, что грубые изменения наблюдались у 14 (5,6%) пациентов с астигматизмом в первой группе и выраженные изменения - у 11 (6,1%) детей с гиперметропическим астигматизмом во второй подгруппе. В данной работе тестирования проводились при помощи Titmus теста на средних расстояниях. Это следует учитывать при проведении оценки стереозрения при помощи градуальных тестов. Выводы. Применение Titmus теста позволяет существенно повысить точность измерения показателей стерео-зрения, сделать скрининговые процедуры более комфортными и увеличить эффективность своевременной диагностики нарушений бинокулярного зрения. Скрининговое исследование стереозрения перспективно, так как позволит существенно повысить качество скрининговой диагностики стереоскопического восприятия.
DOI 10.31718/2077-1096.22.1.29
УДК: 617.764.1-008.8-071
Дун Фан Ху'1, Безкоровайна 1.М.
ВИЗНАЧЕННЯ БЕЗПЕЧНО1 ТРИВАЛОСТ1 ВИКОРИСТАННЯ КОМП'ЮТЕРНИХ ПРИСТРО1В БЕЗ ВПЛИВУ НА СЛ1ЗНУ ПЛ1ВКУ
Полтавський державний медичний уыверситет
Мае мсце недостатне висвтлення проблеми зм/'н товщини лiпiдного шару сл!'зноУ пл'тки, висоти сл'зного менску, ненвазивного часу розриву сл!'зноУ пл'тки при вплив/ комп'ютерних пристроТв до 60 хвилин. Це аргументуе доцльнсть проведення сучасних досл'джень з метою визначення безпечно-го безперервного часу перебування за комп'ютерними пристроями. Мета. Визначити безпечний час роботи за комп'ютерними пристроями без вагомих зм/'н на показники сл!'зно'У пл'тки. Матерiали та методи. Нами було обстежено 335 чоло&к (670 очей) у в'и(! в'д 18 до 48 роюв, у середньому (28±0,74). Дослiдження проходило у два етапи: I - анал'зували сл1зну плiвку без використання комп'ютерних пристроУв; II - анал'зували змни сл!'зноУ пл'тки псля використання комп'ютерних пристроУв. Тож, обстежен/ були об'еднан/ в едину групу, з подальшим анализом слзноТ пл'вки псля впливу комп'ютерних пристроУв протягом 20; 30; 40 та 60 хвилин. Результати досл'дження. Псля 20 хвилин впливу показники товщини лiпiдного шару, NIBUT та частота клпань були близькими до початкових показник'т (р>0,05). Псля 30 хвилин впливу з'явилась тенден^я до помiрного потон-шення лiпiдного шару у 5% обстежених, але р1'зниця виявилася не достов'рною в пор!внянн1' з поча-тковим рiвнем (р>0,05); частота клпань зменшилася у 12% порiвняно з початковими даними (р<0,05);. Псля 40 хвилин впливу кльксть обстежених з помiрним потоншення лiпiдного шару зро-сла до 13% (р<0,05); кльксть обстежених з патолог'чним показником сл'зного менску збльшилися на 11% (р<0,05); частота клпань зменшилася у 26% обстежених в'д початкових даних (р<0,01). П-сля 60 хвилин впливу кльксть обстежених з потоншенням лiпiдного шару зросла до 16% (р<0,01), з них: 3% з'! значним потоншенням лiпiдного шару; ктьюсть обстежених з патолог'чним показником сл'зного менску збльшилися на 16% (р<0,01); кльксть обстежених з порушенням NIBUT збльши-лася на 14% (р<0,01); частота клпань зменшилася у 50% обстежених в'д початкових даних (р<0,01). Висновок. Вплив комп'ютерних пристроУв протягом 20 хвилин не викликае зменшення ча-стоти клпань та не змнюе яксний склад сл!'зно'У пл'тки. Ключов1 слова: сл1зна пл1вка, вплив комп'ютерних пристроТв.
Робота виконана в рамках iнiцiаmиеноi' наукоео-дослiдноi' роботи кафедри «Розробка дiагностичних критерпе змн очноТ по-верхнi за даними iнmерферомеmрii» 0119 и102848.
Враховуючи часте та тривале застосування сучасних електронних пристроТв, частота людей, як користуються розумними комп'ютерними пристроями щодня, досягла 3 годин i бтьше на день або 30 годин i бтьше на тиждень[1,4,14], що дае змогу с^мко розвиватися комп'ютерному зоровому синдрому (КЗС), що викликаний втомою очей [3,4,6,10,12,13,15]. Через тривалу залежнють та використання комп'ютерного обладнання, захворювання очноТ
Вступ
поверхн хвороба сухого ока (ХСО) з'являеться не ттьки у людей похилого вку, але й у бтьшо-CTi молодi з поширенютю 61% [2,5,17]. Згщно 3i статистичним звтом TFOS DEWS II [16], розви-ток КЗС та ХСО мае загальний фактор ризику-тривалий контакт iз комп'ютерною техыкою. При цьому, деяк автори свщчать про ппешчну без-печнють зорово'Т роботи протягом 60 хвилин за комп'ютерними пристроями у оаб старше 18 роюв [9]. Однак, мае мюце недостатне висв^лення проблеми змш товщини лшщного шару с^зно'Т
