PHD theses : Optics
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Item VISION AND VISION-RELATED QUALITY OF LIFE IN PATIENTS WITH SENILE CATARACT(Neelain University, 2012) HIBA MOHAMMED ELHASSAN ALI ELAWADAbstract Purpose: To assess the impact of senile cataract on the patient's visual, functional status and on quality of life. Methods: A cross-sectional, hospital based study was conducted in Makkah Eye Complex in Khartoum Alryad; in the period (October 2009-July 2010). Elderly patients (300); their age varied 60-95 years with senile cataract were asked to participate in the study. Participation was entirely voluntary. Information was collected by means of interviews, questionnaires, observation and clinical assessment. Further study was conducted with professionals for situation analysis: to investigate barriers and factors affecting surgical outcomes. The data were analyzed using SPAW Statistics-18 (2010) a modified version of SPSS. Results: In the presence of cataract the results shows significant declines in all of visual functions (>85% visually impaired). However, the value of IOP was not influenced by cataract presence. Statistically the visual acuity showed high positive correlations and high statistical significance before the surgery (Pearson chi-square p<0.00l) when compared with type of cataract, colour vision, refractive errors, central and peripheral visual field and (Pearson chi-square p<0.005) after surgery. The significant heterogeneous distribution suggests these tests are different but strongly correlated. Physical functions, emotional well-being, safety, and overall quality of life can be enhanced when visual functions are restored by cataract extraction. Improved visual functions as a result of cataract surgery included the following: Better optically corrected vision (71%) achieved satisfactory visual outcomes (Log MAR >0.48) with average distance (VA of 0.36-0.46 Log MAR). Seven percent in border line (Log MAR = 0.48). Increased ability to read and perform near work (average 0.22-0.42 Log MAR); improved ability to function in dim levels of light by increasing contrast sensitivity (1.35-1.65 Log units); improved peripheral (90%) and central visual field (>85%), and improved colour vision (90%). Improved physical functions included the following: Increased ability to perfonn activities of daily living (>93%), and increased mobility (>93%). However, financial conditions and opportunity to continue or resume an occupation remained imchanged (>75% not working). Improved psycho-social health and emotional well-being included the following benefits: Improved self-esteem (>99%), and independence (9%); increased ability to participate in social activities (>76%), and relief from fear of blindness (>1 8%). Surgical outcome criteria can vary for each patient, depending on the patient’s needs, lifestyle, and medical condition. In general, outcome criteria included the following: reduction of visual symptoms, improvement in visual functions, achievement of satisfactory visual outcomes and improvement in quality of life. Conclusions: The role of optometrist in geriatric care is to improve the patient's quality of life by facilitating independence and goal directed activity; to help patients with impaired vision to live useful lives, enjoy self-sufficiency, emotional independence and satisfactory social interactions; (>83%) of patients required optical correction after cataract extraction (70%) had achieved satisfactory visual outcomes. Eventually about 25% could benefit from low vision and rehabilitation services. Health education, treatment, support and opportunity are necessary for patients with senile cataract to remain independent and productive members of their communities. Ageing issues and cataract blindness treatments are challenges to us all: No single player can do it alone. ' Key words: Senile cataract, Visual impairment, Functional vision, Quality of life, Elderly rights, Supportive services, Geriatric optometry.Item VISION AND VISION-RELATED QUALITY OF LIFE IN PATIENTS WITH SENILE CATARACT(Alneelain University, 2012-01) HIBA MOHAMMED ELHASSAN ALI ELAWADAbstract Purpose: To assess the impact of senile cataract on the patient's visual, functional status and on quality of life. Methods: A cross-sectional, hospital based study was conducted in Makkah Eye Complex in Khartoum Alryad; in the period (October 2009-July 2010). Elderly patients (300); their age varied 60-95 years with senile cataract were asked to participate in the study. Participation was entirely voluntary. Information was collected by means of interviews, questionnaires, observation and clinical assessment. Further study was conducted with professionals for situation analysis: to investigate barriers and factors affecting surgical outcomes. The data were analyzed using SPAW Statistics-18 (2010) a modified version of SPSS. Results: In the presence of cataract the results shows significant declines in all of visual functions (>85% visually impaired). However, the value of IOP was not influenced by cataract presence. Statistically the visual acuity showed high positive correlations and high statistical significance before the surgery (Pearson chi-square p<0.00l) when compared with type of cataract, colour vision, refractive errors, central and peripheral visual field and (Pearson chi-square p<0.005) after surgery. The significant heterogeneous distribution suggests these tests are different but strongly correlated. Physical functions, emotional well-being, safety, and overall quality of life can be enhanced when visual functions are restored by cataract extraction. Improved visual functions as a result of cataract surgery included the following: Better optically corrected vision (71%) achieved satisfactory visual outcomes (Log MAR >0.48) with average distance (VA of 0.36-0.46 Log MAR). Seven percent in border line (Log MAR = 0.48). Increased ability to read and perform near work (average 0.22-0.42 Log MAR); improved ability to function in dim levels of light by increasing contrast sensitivity (1.35-1.65 Log units); improved peripheral (90%) and central visual field (>85%), and improved colour vision (90%). Improved physical functions included the following: Increased ability to perfonn activities of daily living (>93%), and increased mobility (>93%). However, financial conditions and opportunity to continue or resume an occupation remained imchanged (>75% not working). Improved psycho-social health and emotional well-being included the following benefits: Improved self-esteem (>99%), and independence (9%); increased ability to participate in social activities (>76%), and relief from fear of blindness (>1 8%). Surgical outcome criteria can vary for each patient, depending on the patient’s needs, lifestyle, and medical condition. In general, outcome criteria included the following: reduction of visual symptoms, improvement in visual functions, achievement of satisfactory visual outcomes and improvement in quality of life. Conclusions: The role of optometrist in geriatric care is to improve the patient's quality of life by facilitating independence and goal directed activity; to help patients with impaired vision to live useful lives, enjoy self-sufficiency, emotional independence and satisfactory social interactions; (>83%) of patients required optical correction after cataract extraction (70%) had achieved satisfactory visual outcomes. Eventually about 25% could benefit from low vision and rehabilitation services. Health education, treatment, support and opportunity are necessary for patients with senile cataract to remain independent and productive members of their communities. Ageing issues and cataract blindness treatments are challenges to us all: No single player can do it alone. ' Key words: Senile cataract, Visual impairment, Functional vision, Quality of life, Elderly rights, Supportive services, Geriatric optometry. 'Item Myopia in Young Sudanese Patients: Ocular Biometry, Macula Integrity and Visual Performance(Neelain University, 2018) Raghda Faisal Abdelfatah MutwalyABSTRACT Aim: The study aimed to investigate ocular biometry, visual performance and macula integrity in myopia, to assess quality of life in myopia and to determine the role of optometrist in management of myopia. The study further aimed to develop myopia care system and to provide the practitioners with basis for defining the clinical features of myopia. Material and Methods: A prospective case control study was conducted at Makkah Eye complex, Khartoum, Sudan in period from June 2015 to June 2017 in 600 young Sudanese subjects (300 myopic and 300 emmetropic). The study was approved by the ethical committee of scientific research deanship at Alneelain University. Then inform consent was gave for each participant before conducting the study and participation was entirely voluntary. Clinical examinations were included assessment of ocular biometry using Lenstar (LS 900 eyes biometer), visual acuity by Log MAR chart, contrast sensitivity by Pelli-Robson chart, colour vision by D-15, central macular field by Amsler grid test and refractive state by auto-refractometer (Nidek AR-310). Macula integrity was investigated by optical coherence tomographer (Carl Ziess OCT). In addition, vision-related quality of life was measured by NEI-VFQ. The role of optometrist in management of myopia was assessed by using special questionnaire. Then, data were analyzed by SPSS-24. Results: the study included 300 myopic patients (45% males and 55% females). Their mean age 25.3±6.6years (range: 15-35 years). The mean of spherical equivalent myopia was 7.7±6D (range: -1 to -25D). Myopia was subdivided into low, moderate, high and pathologic myopia with sphere equivalent of 2.25±0.55D, 4.02±0.81D, 8.20±1.67D and 9.21±7.27D respectively. Unaided visual acuity was 1.08±0.27 (range: 0.4-1.5) which improved to 0.28±0.31 with spectacle correction (p˂0.001). Eyes with pathologic myopia had visual impairment (0.77±0.17). The mean of contrast sensitivity was 1.51±0.37 (range: 0.15-0.25). Eyes with high myopia and pathological myopia had low contrast sensitivity (1.24±0.25). In addition, colour vision defect presented tritanomaly in 21.7%, protanomaly in 12.5% and deutanomaly in 9.2% of eyes. Central macular field demonstrated metamorphopsia in 31.8%, central scotoma in 4.2%, blurring in 8.8% and colour scotoma in 4.8% of eyes. The mean of axial length in myopic eyes was 25.89±0.69mm (range: 23.06-30.25mm). The mean of central corneal thickness was 524.60±30.66µm (range: 402-582µm). The mean of anterior chamber depth was 3.14±0.42mm (ranged 1.09-4.17mm). Axial length, anterior chamber depth and central corneal thickness had positive association with the progression of myopia (p˂0.001). However, the mean of macula thickness in myopic eyes was 262.39±22.68µm (range: 199-302µm), with significant difference between males (264.56±22.78µm) and females (250.63±22.48µm) (p˂0.001). The mean of macula volume in myopic eyes was 9.41±0.89µm3 (range: 6.9-10.9µm3) with significant difference between genders (p˂0.001). Mean of fovea thickness was 243.86±29.84µm (range 190 to 300µm). Parafovea thickness was 296.77±25.72µm (range: 218-342µm) and perifovea thickness was 262.23±22.47µm (range: 203-230µm). Moreover, the mean thickness of ganglion cell complex was 69.72±21.09µm (range: 20-44µm). All of the macula parameters had negative association with progression of myopia except the fovea which had positive association with progression of myopia (p˂0.001). In addition, high myopia presented staphyloma in 5.5% of eyes and posterior vitreous detachment in 18.67% of eyes. Eyes with myopic maculopathy demonstrated epiretinal membrane in 5.7%, vitreomacular traction in 4.5%, macular retinoschisis in 2.5%, and retinal detachment in 1.8% as well as lamellar macular hole in 1.5% of eyes. The quality of life in myopic patients was lower (65%) than emmetropic subjects (95%) (p˂0.001). The knowledge of optometrist about myopia control methods was good (68.2%). Conclusion: In youth with high myopia reduction on macula thickness and volume was found as well as thinning in ganglion cell complex, but foveal thickness and anterior chamber depth were increased. Pathologic myopia caused atrophy of ganglion cell complex and maculopathy which lead to visual impairment. The common colour vision defect is tritanomaly and common macula field defect is metamorphopsia. Epiretinal membrane and macula retinoschisis were common in eyes with pathologic myopia. Keywords: Myopia, optical coherence tomography, myopic maculopathy, metamorphopsia, tritanomaly, myopia control, myopia care system. جامعة النيلين كلية الدراسات العليا قصر النظر لدى الشباب السودانيين: القياسات العينية، مدى سلامة مركز الابصار والكفاءة البصرية رغده فيصل عبد الفتاح متولي رسالة دكتوراة في علوم البصريات الخلاصة الهدف: تهدف الدراسة الى تقييم القياسات العينية، الكفاءة البصرية ومدى سلامة مركز الابصار لدى الشباب المصابين بقصر النظر، تقييم طبيعة الحياة لديهم وتحديد دور اختصاصي البصريات في علاج قصر النظر. كما تهدف الى تكوين نظام لعلاج قصر النظر ومد الاختصاصين بأساسيات لتعريف العلامات الاكلينيكية لقصر النظر. المواد والطرق: هذه دراسة اكلينيكية تستخدم عينة ضابطة تم اجراؤها بمستشفى مكة لطب العيون، الخرطوم، السودان في الفترة من يونيو 2015 الى يونيو 2017 على 600 من الشباب السودانيين (300 لديهم قصر نظر و300 طبيعيين). تمت الموافقة على الدراسة من قبل لجنة أخلاقيات البحث العلمي بعمادة البحث العلمي بجامعة النيلين. كما تم اعطاء جميع المشاركين اقرار بالمشاركة في الدراسة، حيث أن المشاركة طوعية. اشتملت الكشوفات الاكلينيكية على تقييم القياسات العينية باستخدام جهاز القياسات العينية، حدة الابصار باستخدام لوحة اللوغريثم، حساسية التبيان، رؤية الالوان، ميدان النظر المركزي والحالة الانكسارية للعين. كذلك تم تقييم مركز الابصار بواسطة جهاز تخطيط الشبكية البصري المقطعي. بالاضافة الى ذلك تم قياس طبيعة الحياة باستخدام استبيان خاص مصمم بواسطة المعهد العالمي للعيون. كما تم تقييم دور اختصاصي البصريات في علاج قصر النظر بواسطة استبيان صمم عن طريق الباحث. كذلك تم تحليل البيانات باستخدام برنامج الحزم الائحصائية للعلوم الاجتماعية، الطبعة رقم 24. النتائج: اشتملت الدراسة على 300 مريض مصاب بقصر النظر (45% ذكور و55% اناث). متوسط أعمارهم ±25.3 6.6 سنة (تتراوح بين 15 و35 سنة). متوسط قصر النظر الكروي المتكافئ يساوي ±7.7 6 ديوبتر (يتراوح بين 1 الى 25 ديوبتر). حيث أن متوسط الخطأ الانكساري في حالات قصر النظر ذو الدرجات البسيطة، المتوسطة، العالية وقصر النظر المرضي تساوي 2.25 ± 0.55 ديوبتر، 4.02± 0.81 ديوبتر، 8.20± 1.67 ديويتر و9.21±7.27 على التوالي. كذلك متوسط حدة الابصارغير المصحح يساوي 1.08±0.55 الذي تحسن الى 0.28±0.31 بواسطة النظارة الطبية مع وجود فرق ذو دلالة احصائية. العيون المصابة بقصر النظر المرضي لديها اعاقة بصرية (0.77±0.17). كذلك متوسط حساسية التباين يساوي 1.51±0.37. حيث أن العيون المصابة بدرجة عالية من قصر النظر، سواء كانت مصاحبة لها تغييرات مرضية في العين أم لا لديها انخفاض في حساسية التباين (1.24±±0.25). كما أن كشف الألوان أوضح وجود خلل في رؤية اللون الأزرق في 21.7% من العيون، اللون الأحمر في 12.5% من العيون واللون الأخضر في 9.5% من العيون. أوضح كشف ميدان النظر المركزي وجود تشوهات في الصورة (31.8% من العيون)، منطقة غير مرئية في المنتصف (4.2% من العيون)، عدم القدرة على الرؤية في حالة الخلفية الملونة (4.8% من العيون). بالاضافة الى ذلك، متوسط طول العيون المصابة بقصر النظر يساوي 25.89±0.69ملم (تتراوح بين 23.06-30.35ملم). متوسط سمك القرنية المركزي يساوي 524.60±30.66ميكروميتر (يتراوح بين 402-582ميكروميتر). كذلك متوسط عمق الغرفة الأمامية للعيون يساوي 3.14±0.42ملم (تتراوح بين 1.09-4.17ملم). طول العين، عمق الغرقة الأمامية وسمك القرنية المركزي لهم علاقة موجبة مع زيادة درجة قصر النظر. كما أوضحت الدراسة أن متوسط سمك مركز الابصار في العيون المصابة بقصر النظر يساوي 262.39±22.68ميكروميتر مع وجود فروقات ذات دلالة احصائية بين الذكور(264.56±22.78ميكروميتر) والاناث ( 250.63±22.48 ميكروميتر). متوسط حجم مركز الابصار يساوي 9.41±0.89ميكوميتر مكعب مع وجود فروقات ذات دلالة احصائية بين الجنسين. كذلك سمك البقعة الصفراء، الدائرة الداخلية من مركز الابصار والدائرة الخارجية من مركز الابصار تساوي 243.86±29.84 ميكروميتر، 296.77±25.72ميكروميتر و262.23±22.47 ميكروميتر على التوالي. أوضحت الدراسة أن جميع قياسات مركز الابصار لها علاقة عكسية مع درجة قصر النظر وطول العين باستثناء البقعة الصفراء حيث لها علاقة طردية. بالاضافة ال ذلك، قصر النظر ذو الدرجات االعالية أوضح وجود بروز خلفى للعين في 5.5% من العيون و انفصال السائل الزجاجي الخلفي في 18.67%. كما أن العيون المصابة يتشوهات مركز الابصار أوضحت وجود غشاء أمام الشبكيية في 5.7% من العيون، شد في منطقة اتصال السائل الزجاجي بمركز الابصار في 4.5%، تمزق مركز الابصار في 2.5% من العيون، انفصال الشبكية في 1.8% من العيون وثقب جزئي في مركز الابصار في 1.5% من العيون. طبيعة الحياة لدى الاشخاص المصابين بقصر النظر(65%) أقل من الاشخاص الطبيعيين (95%) مع وجود فرق ذو دلالة احصائية. كما أوضحت الدراسة أن معرفة اختصاصي البصريات بالوسائل التى تعمل على التحكم في تطور قصر النظر جيدة (68.2%). الخلاصة: في الشباب المصابين بدرجة عالية من قصر النظر يوجد نقصان في سمك وحجم مركز الابصار كما يوجد نقصان في سمك طبقة الخلايا العقدية بالشبكية، بينما توجد زيادة في سمك البقعة الصفراء وعمق الغرفة الامامية للعين. قصر النظر المرضي يسبب تليف في طبقة الخلايا العقدية بالشبكية، كما يسبب تشوهات في مركز الابصار تؤدي الى اعاقة بصرية. كذلك، عدم القدرة على رؤية اللون الازرق هي أكثر أنواع مشاكل رؤية الألوان شيوعا. كما أن تشوه ميدان النظر المركزي يمثل أكثر أنواع مشاكل ميدان النظر شيوعا لدى الاشخاص المصابين بقصر النظر المرضي. كذلك أوضحت الدراسة أن أكثر أنواع تشوهات مركز الابصار شيوعا هي الغشاء فوق الشبكية وتمزق البقعة الصفراء. الكلمات المفتاحية: قصر النظر، تخطيط الشبكية البصري المقطعي، تشوهات مركز الابصار، تشوه ميدان النظر المركزي، خلل في رؤية اللون الأزرق، التحكم في قصر النظر، نظام علاج قصر النظر.Item Effectiveness of Vision Therapy for Convergence Insufficiency in Secondary School Students(Neelain University, 2018) Layali Ibrahim HassanABSTRACT Effectiveness of Vision Therapy for Convergence Insufficiency in Secondary School Students out over 6 weeks under controlled conditions to determine improvement in the signs and symptoms associated with CI. Study Purpose: The purpose of this study was to determine the effectiveness of four different techniques of vision therapy (VT) for convergence insufficiency (CI). The treatment was carried population and methods: The Convergence Insufficiency Treatment Trial (CITT) was conducted in Khartoum North Locality in Sudan and included a total of 329 students with CI, with a mean age of 15.5 ± 2.5 years. They were divided into four groups that underwent different types of VT including pencil push-up (66 students), dot card (66 students), Brock string (66 students), and cat card therapy (65 students), and compared with a placebo control group (66 students). The Convergence Insufficiency Symptoms Survey Score (CISS), near point of convergence (NPC), and positive fusional vergence (PFV) at near vision were evaluated. Data were collected at the commencement of the treatment and after 3 and 6 weeks of treatment. The participants were advised to carry out the procedures at home for 10 minutes per day, 5 days a week, for a total duration of 6 weeks. Results: On primary screening of 4211 students, 329 (7.8%) were diagnosed with CI, of which 52.6% were male, and 47.4% were female students. The majority of students with CI (43%) were from model schools. After 6 weeks of treatment, dot card therapy resulted in the greatest improvement in the CISS by a mean value of 13.6 points (P = 0.001). The pencil push-up therapy was most effective in improving NPC by a mean value of 5.6 cm (P = 0.001). The cat card therapy group revealed the best results in terms of improvement in PFV at near vision by a mean value of 7.3 PD (P = 0.001). Conclusion: VT is effective for patients with CI. However, there is no uniformly effective treatment modality suitable for all patients. The therapist should deal with patients on an individual basis. Key words: Convergence insufficiency, Convergence Insufficiency Treatment Trial, Vision therapy. الملخص فعالية العلاج البصري في قصور التقارب عند طلاب المدارس الثانوية الهدف: الغرض من هذه الدراسة هو تقييم فعالية أربعة من تقنيات العلاج البصري لعلاج قصور التقارب خلال فترة ستة أسابيع تحت ظروف قياسية وذلك عن طريق تقييم التحسن في الأعراض والعلامات المصاحبة له. مجتمع الدراسة والطرق: تم اجراء العلاج التجريبي لقصور التقارب في محلية الخرطوم شمال في السودان. شارك فيها 329 طالبا بلغ متوسط اعمارهم 15.5 ± 2.5 عاما مصابين بقصور التقارب. تم تقسيم الطلاب إلى أربع مجموعات اجروا انواع مختلفة من العلاج البصري هي: مجموعة العلاج بدفع القلم (66 طالبا)، ببطاقة النقطة (66 طالبا) بسلسلة بروك (66 طالبا) وببطاقة القطة (65 طالبا)، مقابل المجموعة الضابطة بالعلاج الوهمي (66 طالبا). تم جمع البيانات باستخدام ثلاثة مقاييس هي: استبيان قياس الشكوى لقصور التقارب (CISS)، ونقطة التقارب القريبة وتقارب الدمج الموجب في الرؤية القريبة. تم جمع البيانات خلال عدة نقاط زمنية وهي: عند بداية العلاج، عند ثلاثة أسابيع، وعند ستة أسابيع من العلاج. وقد أعطيت التعليمات للمشاركين بالقيام بهذه العملية في المنزل لمدة عشر دقائق يوميا لخمسة أيام في الأسبوع لستة أسابيع. النتائج: اظهر مسح المدارس لعدد 4211 طالب ان هناك 329 طالب (7.8%) مصابين بقصور التقارب. منهم (%52.6) ذكور و (%47.4) اناث, أغلبهم (43%) طالب ينتمون الى المدارس النموذجية. بعد مرور 6 أسابيع من العلاج البصري، أظهرت مجموعة العلاج ببطاقة النقطة أفضل نتيجة في تقليل درجة شكوى قصور التقارب ب مقدار13.6 نقطة (P=0.001). كما أن مجموعة العلاج بدفع القلم حققت أفضل نتيجة في تحسين نقطة التقارب القريبة بمقدار 5.6 سم (P=0.001). وأظهرت مجموعة العلاج ببطاقة القطة أفضل نتيجة في تحسين تقارب الدمج الموجب في الرؤية القريبة بمقدار 7.3 قوة منشور(P=0.001) . الخلاصة: العلاج البصري هو علاج فعال للمرضى المصابين بقصور التقارب. لا يوجد علاج موحد لجميع المرضى الذين يعانون من قصور التقارب فالمعالج يجب أن يتعامل مع كل مريض على حسب حالته. الكلمات المفتاحية: قصور التقارب، العلاج التجريبي لقصور التقارب، العلاج البصري.Item Optical and Visual Assessment of Ophthalmic Plastic Lenses in Hot and Dusty Climate(Al Neelain University, 2014-03) Abdelaziz Mohammed ElmadinaBackground: One of the popular spectacle lenses is plastic (CR 39) lenses. However, plastic materials in general inherited some defects. Purpose: This study investigated optical changes in spectacle lenses afier use for a period of one year, the quality and visual perfonnance. Methods: The investigations included the storage of the uncut lenses, thermal exposure lenses, use as spectacles (cleaning and keeping in spectacle case), visual perfomance (visual acuity, contrast sensitivity, stereo acuity, colour vision and central field) and users‘ satisfaction (weight, cost, rate of change and preference). Samples size was 264 of the (CR 39) plastic white lenses, divided into; group A 144 lenses prepared in spectacles to study optical changes and effect on visual perfonnances, group B 30 lenses exposed to indoor environmental conditions for one year and group C 90 lenses exposed to thermal conditions. Lenses parameters investigated were transmission, center thickness, surface curvature (for group A in different meridians) and dioptric powers. In addition, a questionnaire was designed to assess plastic lenses wearers’ satisfaction in Khartoum. Results: Transmission results revealed insignificant changes in group A, B and C after 12 month. Center thickness of group A lenses (R, L) showed a significant change afier 6 month and group C lenses post heat treatment (p< 0.001, = 0.003 and < 0.001) respectively. Only the 180 axis in L front surface group A lenses had shown insignificant change (p =0.174, 0.960; 0.562) at the start point, after 6 month and after l2month. However, no change were detected in the power of these lenses, but a significant change was found in front and back radii of curvature (r|, T1) and power of group C lenses afier exposure to heat (p < 0.001), (p = 0.013) respectively. Stable visual perfonnance was noted by spectacles users, but a significant difference in visual acuity after 12 month (p= 0.037) in lefi eyes was found. Spectacles lenses scratching afier 12 month was found considerable (p< 0.001) attributed to the use of dry cleaner by 70.8 % of spectacles users. Results also showed that 87.5% participants were comfort with plastic lenses, while 91.7 % were preferring plastic for their new spectacles. According to the questionnaire results a significant element of comfort 96% in vision was noted in using CR 39 ophthalmic spectacles lenses in Khartoum, furthermore, 99.7% of the subjects stated that CR 39 lenses have light weight compared with ophthalmic glass lenses; however 89.5% users clearly stated that durability was poor for those type of lenses; while 96% of the participants pointed that the lenses were safer compared to the ophthalmic glass lenses. lt was found that scratches were the main cause of lens colour changes p=0.00l and visual blurring p = 0.007, however; spectacles’ cases were found to be a significant cause of scratches; while 83.1% preferred plastic for their new spectacles. The causes for changing spectacles were found to be scratches (93%) and discomfort (80%). Blurring of vision was found to be in 57.6% and colour changes were 41.1% of the studied group. Conclusion: CR.39 plastic lenses had good stability in transmission, center thickness, vertex power (except when heated, group C), surface curvature showed significant change. Visual perfonnances were found stable with wearing CR 39. Comfort was good, and plastic lenses were preferable and safe for group A wearers and questionnaire participants. However, the main drawback short durability. Scratches were found to have considerable role in vision blurring and discomfort, attributed to the use of improper spectacle cases and the use of dry cleaners to wipe lenses clear.Item The Impact of Use of Hydrogel Contact Lenses on the Visual Functions among University Students(Neelain University, 2016) El-Bashir El-Saeed El-Bashir Gar El-NabiABSTRACT This study is composed of three phases, the first, second and three. In the first and second phases the study is a longitudinal (prospective) clinical hospital-based study, carried in October 2011 to June 2014 in the Faculty of Optometry and Visual Science (eye hospital), AL-Neelain University, Khartoum, Sudan. The first phase of the study aimed to determine the effects of long- term soft contact lens daily wear on visual functions in young adult Sudanese subjects, and the second phase aimed to investigate and assess patient’s visual response, comfort, symptoms, complications and overall satisfaction. A total 63 (12 males, 51 females) young adults Sudanese neophyte (who never worn contact lens before), were recruited to be involved in the study. Their ages ranged between 18 to 38 years of ages. Routine eye examination was carried and all subjects were fitted with clear hydrogel lenses (CLEVIO) (water content 38%) POTEC Co. LTD for one year. Testing of vision, contrast sensitivity, stereoscopic vision, central visual field, and color vision were examined on each follow up visits. Follow up visits for examination was at 2 weeks, 1, 3,6,12 months. In our study hydrogel contact lens wearers showed a significantly drop in contrast sensitivity and stereoscopic vision. Whoever, there were no changes in colour vision and central visual fields. The second phase aimed to assess the patient’s visual response, comfort, symptoms, complications and overall satisfaction of patients wearing corrective hydrogel contact lenses. It concluded that the visual and comfort response during all follow up visits revealed that the majority of participants had excellent visual and comfort response and only one patient showed poor visual and comfort response. In the early aftercare visits most of subjects were found to be free from signs and symptom due to contact lens and few subjects complained of burning, foreign body sensation, itching, dryness, tearing, photophobia, scratchiness, and redness, at late aftercare visits. There was no serious complications occurred during examinations except 7 subjects who had corneal staining, edema, ulcer, injections and lens deposits at late stages of follow up visits. All participants were extremely satisfied and only one had low level of satisfaction. The third phase aimed to assess awareness of contact lens wear among students of Al-Neelain University, Khartoum, Sudan. A total of 450 students were enrolled in this study. In this phase the level of understanding about contact lenses was found to be high among most of participants, the main source of their information they reported were televisions, followed by internet, friends and relatives, radio, magazines and newspapers. Most of students knew therapeutic and cosmetics contact lenses and few of them heard about corrective contact lenses. Most of the participant who wore contact lenses before reported they used it without prescription and few of them had prescription. About their opinions and considerations about contact lenses we concluded the following: Most of respondents reported they get contact lenses from optical centers, pharmacies and few of them reported beauty centers. 50.4% of students reported that the contact lenses could hurt their eyes and vision, while 46.4% assumed that it’s safe and comfortable. Most of participants prefer spectacle over contact lenses to correct their refractive errors. Regarding the alternative method to correct their errors most of them reported contact lenses were the best alternative for glasses other reported they preferred LASIK method. Knowledge about contact lenses have an expiration date most of them reported yes while few of them assumed that they are not expired. The study showed that most of respondents do not shared their contact lenses with others and few of them believed that they can do; most of them thought they do not sleep with lenses. 58.4% of participants reported that there was special solution should be used to care for lenses, followed by 22.2% of them thought they should use tap water , 15.8% believed they should use distilled water and 0.4% thought it could be licked by their mouth to keep lenses clean and sterile. Most of them reported that contact lenses should be cleaned before and after use and they thought that there were no special hours per day to wear the contact lenses. Most of participants believed that the main reasons for restricted use of contact lenses were due to environmental condition, lack of knowledge, when not advised by specialists and economic status of participants. The findings indicate that the best method to increase awareness and understanding of contact lenses wear among Sudanese population by the use of bulletin and programs, training and promotion. Key words: hydrogel lenses, visual acuity, contrast sensitivity, stereo acuity, central visual field, color vision, daily wear, optometrists, complications, increase awareness of contact lens.