كلية علوم البصريات
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Item The Effect Of Fixation DisparityOn Binocular Visual Acuity(AL-Neelain University, 2002-08) Done By Faiza HamdallaAbstract This project is carried out in binocular visual acuity in the presence of fixation disparity created by prisms A sample of 20 young adults was surveyed in clinics of Faculty of Optometry and Visual Science and they had good binocular vision, reduction in binocular visual acuity with the magnitude of fixation disparity was found, to achieve our original goals a clinical investigation was carried out in normal subject with good vision (6/5) symptoms free. By using loose prisms (3-5-7-9-11). The induced misalignment of the visual axis is present and it varied from one patient to another, the vision decreased due to displaced retinal image, and there was a direct relationship between prism dioptre and fixation disparity, and an indirect relation between visual acuity and the induced fixation disparity. The subjects were selected randomly including both males and females. The age variation ranged between (21-25) years. The criteria for selection included normal binocular single vision, symptoms free. Data gathered were tabulated and calculation included frequency percentage means- standard deviation and T-test were significant, the result of induced phenomenon comparing with Log-Mar (Test vision) and the displacement of retinal image by mms, were explain the indirect relation between binocular visual acuity to the induce fixation disparity. The key words were fixation disparity and visual acuity.Item The Effect of Myopia on Vision,Accommodation, Convergence and Pupil Size(AL-Neelain University, 2002-09) Nuha Mohamed Fath AL RahmanItem The lnduced changes in corneal cur vature following Aslk for myopia at makka Eye compley(AlNeelain University, 2009) Ragda Faisal Abdel Fatah MntwalyItem The Effect of sim ulated stress on Associated Heterophoria Atneear vision(Al-Neelain University, 2002) Ahmed Ali Ahmed EI NimaryItem ’Vi'sua[ outcome of phacoemulsification Surgery;ln Elwalidain Eye Hospital(2005-07) Mustafa Abdu Ali MohammedIntroduction l.l Statement of the problem Czttnruet is the lending euuse nl‘ blindness in the world us well us in Sudun. ln Sutlun. due tn CllLl|'LlClCl'lSllC en\=i|'0nmentul conditions 0|‘ sttb-Suhurun Africa and poor suuinnult rcgio|1s_ the problem olieatturuet represents (>t)% out oliull catses 01‘ blindness, ll't'CS]7t,'t'll\'C or ll.\ type. ezttunlet is present in ull regions uliSudzut. The total number of eatumct surgeries tll Ztltll was 28500. The pereentuge otltll eutztruet surgeries with IOL is 55%. Cuturuct surgteul rule (CSR)/million popttlutiuit / ycurs ts ‘)5().m Phaeoemulsificution is one ofthe procedures used to prevent blindness by cattatntcl Ill Sudun since 200]. 1.2 Objectives of the study This study ztims t0:- I Highlight experience in plmcoetnulstlicutinn procedure in Stitlaur 0 Estimute the \'l§tli\l uutcuine utithe |1roeedure. l.3 Metliotlology and smiree of data In this Cl'OSS-SCCllOl1;ll_ retrospective study. records of I20 consecutive patients \\lu» were operated by phucoemulsitieutinn in El waliduin eye hospital from l\/lurch to July Ztltti. ure included. The study was constructed lu describe stntisticul tests that include pel‘eeitt;t-__'e.<_ meuns. _~:tnndurd deviutiun and chi-test.Item The Effect Of Fixation Disparity On Binocular Visual Acuity(2002-08) Faiza HamdallaAbstract This project is carried out in binocular visual acuity in the presence of fixation disparity created by prisms A sample of 20 young adults was surveyed in clinics of Faculty of Optometry and Visual Science and they had good binocular vision, reduction in binocular visual acuity with the magnitude of fixation disparity was found, to achieve our original goals a clinical investigation was carried out in normal subject with good vision (6/5) symptoms free. By using loose prisms (3-5-7-9-11). The induced misalignment of the visual axis is present and it varied from one patient to another, the vision decreased due to displaced retinal image, and there was a direct relationship between prism dioptre and fixation disparity, and an indirect relation between visual acuity and the induced fixation disparity. The subjects were selected randomly including both males and females. The age variation ranged between (21-25) years. The criteria for selection included normal binocular single vision, symptoms free. Data gathered were tabulated and calculation included frequency percentage means- standard deviation and T-test were significant, the result of induced phenomenon comparing with Log-Mar (Test vision) and the displacement of retinal image by mms, were explain the indirect relation between binocular visual acuity to the induce fixation disparity. The key words were fixation disparity and visual acuity.Item CROWDING PHENOMENON (In Unilateral Aniso-hypormotropic Amblyopia) (Analytlcal Study(ALNeelain University, 2008) Mustafa Gamar Eldin Bashir Haj AhmedACKNOWLEDGEMENT Gratitude and thankfulness to: 0 Professor Hashim Mangiel the supervisor of this study I owed him much for his atmost attention, guidance, information he oflered regarding the study and firm directions to be on the way of research.. 0 Dr. Mohamed Alhassan Ali Alawad, Dean Faculty of Optometry & Visual Science for his kind welcoming open doors, and useful instructions to build up a research. 0 Thanks & gratitude to stafi’ of the Graduate College of the University of Al- Neelain for the facilities they gave and assistance. 0 Colleagues and library stafl of the Faculty of Opt. & Visual Science for their endless cooperation and help. Q Subjects of the study for their patience, cooperation, and immediate consent to bear the burden of the examinations. I Many thanks to everyone who gave a hand, to realize this study; I consider them anyhow, as participants in the creation of this study. 0 Special thanks to Dr. F arouk Suliman for his incredible help and guidance.Item Theffect of redued binocular visual Acuitt on stereoacuity(AL-Neelain University, 2002-09) EL-BASHIR ‘EL-SAEED EL-BASHIRAbstract This study investigated the effect of optical blur (defocus) on stereoacuity measured by Titmus stereotest. 1n 60 subjects (30 males and 30 females) with nomqal visual acuity and demonstrated near stereoacuity of 40 seconds of arc. Ages enrolled were from 18 to 36 years. The subjects were selected randomly from Faculty of Optometry and Visual Science Clinic (In Khartoum). All subjects were enrolled in the experiment, in which the visual acuity of each subject was blurred (positive and negative blur was conducted), by (1,2 and 3D.Sph) lenses first binocularly and second monocularly, then the stereoacuity was measured by using Titmus stereotest. The drop of stereoacuity was found to be greater with monocular than binocular blur. The average drops due to binocular blur were found to be 49.7 seconds (of arc) with -1.00 D.Sph, 54.2 seconds with -2.00 D.Sph, 189.2 seconds. with -3.00 D.Sph, 50 seconds with +1.00 D.Sph, 260.8 seconds with +2.00 D.Sph and 2180.3 seconds with +3.00 D.Sph. The average drops of monocular blur were 143.8 seconds with —1.00 D.Sph, 1333.7 seconds with —2.00 D.Sph, 2712.3 seconds with -3.00 D.Sph, 92.2 seconds with +1.00 D.Sph, 1701.7 seconds with +2.00 D.Sph and 3000 seconds with +3.00 D.Sph. From this study the positive optical blur was found to cause more drop in the sterescopic acuity than negative optical blur. Key words: Visual acuity, binocular vision, stereoacuity, optical blurs.Item LIGHT INTENSITY AS MEANS FOR MEASURING LENS POWERS(AL-Neelain University, 2008 - 04) MADIHA SID AIIMED ALI MOI IAMICDAbstract This study was carried out to prove the possibility of using light intensity as means in the measurement of lens power. Seven different procedures were used for measuring power of lenses selected randomly from three international trial sets (English, Indian. and Chinese). Powers of (185) lenses were measured; (137) were spherical lenses and (48) were cylindrical ones. 6 to 10 readings were taken at variable distances between the tested lens and the light meter, to gain various intensities of light. Some experiments were carried out by using an optical bench and others by a modified optical bench. A linear equation relating the light intensity to the detector distance was applied to obtain the results. Parallel ray method for concave lenses showed good results with a high intensity; when ophthalmoscope and 12volt lamp were used. Here the uses of the modified optical bench gave better results than the ordinary optical bench; because the tilting error was increased with the latter. However, when the light intensity was low (3.5volt), the modified optical bench results were worse, due to the aperture factor, which increases the aperture error. Hence the light disc incident on the detector becomes larger with non parallel method and that decreases the aperture error. Convex lenses had got good results with this method especially with the use of new battery rather than parallel ray method. Upon increasing the lens power, the light disc on the detector was decreased and this increased the aperture error. Generally, cylindrical lenses showed good results. Convex cylindrical lenses with parallel rays exhibited more accurate results than spherical convex lenses with the same method. Although the intensity of light was higher for the latter (ophthalmoscope), the aperture error in cylindrical lenses is less severe and that because it is confined to only one meridian. Key words: - Light — intensity — lenses - power ~ optical bench.Item OPTOMETRY AND VISUAL SCIENCE The Effect of Myopia on Vision, Accommodation, Convergence and Pupil Size(ALNeelain Unviersity, 2002-09) Nuha Mohamed Fath AL Rahman.1: Introduction This chapter represents information historical review and previous studies that have investigated myopia and its effect on vision, pupil size, accommodation and convergence. Section (2.2) considers definition of the term myopia and gives a short account about its history, etiology, classification, clinical picture and treatment along with visual disability. Section (2.3) covers the pupil. Section (2.4) considers accommodation and its relation to refractive errors, convergence and pupil. Section