38 results on '"Ahmed A. Assaf"'
Search Results
2. MicroPulse® transscleral laser therapy in the management of glaucoma patients
- Author
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Ahmed Hassan Assaf, A.M. ELGwaily, S.A. Khedr, Ahmed Abdel Meguid Abdel latif, M.A.M.A.L. Latif, and H.A. Elsayed
- Subjects
medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,Visual Acuity ,Glaucoma ,Laser therapy ,Ophthalmology ,medicine ,Humans ,Prospective Studies ,Intraocular Pressure ,Laser Coagulation ,business.industry ,Ciliary Body ,General Medicine ,University hospital ,medicine.disease ,eye diseases ,Treatment Outcome ,Laser Therapy ,sense organs ,medicine.symptom ,business ,After treatment - Abstract
To evaluate the efficacy and safety of MicroPulse® transscleral laser therapy (TLT) in the management of glaucoma patients.A prospective, interventional, non-comparative case series was conducted in the department of ophthalmology, Ain Shams University Hospital on 61 eyes of 46 patients with various glaucoma types and of severity, ranging from mild to severe. In addition to best-corrected visual acuity (BCVA), intraocular pressure (IOP) and the number of glaucoma medications were recorded before and after treatment, along with the postoperative need for systemic carbonic anhydrase inhibitors (CAI), success rates, number of treatment sessions and postoperative complications. Success was defined as an IOP of 6-18 mmHg or at least a 30% decrease from preoperative IOP in the absence of any vision-threatening complications during the 6-month follow-up period.MicroPulse TLT was performed on 61 glaucomatous eyes. Eleven of the 61 eyes (18%) that did not achieve IOP between 6-18 mmHg, or at least a 30% decrease from baseline at 6 months, had a repeat MicroPulse TLT session. At 6 months follow-up post a single MicroPulse TLT session, the mean IOP reduction was 35.9 ± 14.2%; and 6 months after the second session, it was 36.2 ± 17.5% (p 0.001). The success rate after the first session was 73.8% which increased to 78.7% after the second session. The mean anterior chamber (AC) cell reaction was +1.9 ± 0.8 at 1 day, +1.0 ± 0.7 at 1 week, and +0.2 ± 0.4 at 1 month postoperatively. No cells were detected in any of the cases at 3 and 6 months follow-up (p 0.001). The average number of anti-glaucoma eye drops before MicroPulse TLT was 2.6 ± 1.0. Postintervention, the average number of anti-glaucoma eye drops was 1.7 ± 1.2, and sustained at 6 months follow-up after the last treatment session (p 0.001). There were no significant complications were noted. One eye developed transient hypotony for 3 months after MicroPulse TLT.MicroPulse TLT is safe and effective in lowering IOP in a variety of glaucoma types and severity.
- Published
- 2021
3. Terapia láser transescleral de micropulsos en el manejo de los pacientes de glaucoma
- Author
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Ahmed Hassan Assaf, Amr Mohamed ELGwaily, Ahmed Abdel Meguid Abdel latif, Mahmoud A Meguid A Latif Latif, Shaker Ahmed Khedrrrr, and Hassan Ahmad Elsayed
- Subjects
03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,030221 ophthalmology & optometry ,030217 neurology & neurosurgery - Abstract
Resumen Objetivo Evaluar la eficacia y seguridad de la terapia laser transescleral MicroPulse® (TLT) en el tratamiento de pacientes con glaucoma. Metodos Se llevo a cabo una serie de casos prospectiva, intervencionista y no comparativa en el Servicio de Oftalmologia del Hospital Universitario Ain Shams en 61 ojos de 46 pacientes con diversos tipos de glaucoma y de gravedad, de leves a graves. Ademas de la agudeza visual mejor corregida, se registraron la presion intraocular (PIO) y el numero de medicamentos para el glaucoma antes y despues del tratamiento, junto con la necesidad postoperatoria de inhibidores sistemicos de la anhidrasa carbonica, las tasas de exito, el numero de sesiones de tratamiento y las complicaciones postoperatorias. El exito se definio como una PIO de 6-18 mm Hg o una disminucion de al menos el 30% de la PIO preoperatoria en ausencia de complicaciones que amenazaran la vision durante el periodo de seguimiento de 6 meses. Resultados Se realizo la TLT MicroPulse® en 61 ojos glaucomatosos. Se repitio la sesion de TLT MicroPulse® en 11 de los 61 ojos (18%) que no alcanzaron una PIO entre 6 y 18 mm Hg, o una disminucion de al menos el 30% con respecto al valor inicial a los 6 meses. A los 6 meses de seguimiento tras una unica sesion de TLT MicroPulse® la reduccion media de la PIO fue del 35,9% ± 14,2%, y 6 meses despues de la segunda sesion fue del 36,2% ± 17,5% (p Conclusiones El TLT MicroPulse es seguro y eficaz para reducir la PIO en una variedad de tipos y gravedad de glaucoma.
- Published
- 2021
4. Reasons for Hand Pulling Public Employees from Their Position and Judicial Oversight of the Decision to Pull Hand in The Iraqi and Jordanian Laws
- Author
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Abdulwahhab Gumaah Al-Kubissi and Shatha Ahmed Al-Assaf
- Abstract
This research focuses on the reasons for withdrawing the public employees hand from his position in the Iraqi and Jordanian Laws and judicial oversight over the decision to withdraw. He public employees. The research tries to answer a very important problem which is the extent of the legal regulation for the reasons for withdrawing the employees hand from the work of this job and the judicial: The first topic focuses on the reasons for withdrawing the public employees hand from his position. The second topic deals topic deals with judicial oversight of decisions to withdraw the employees hand from his position. A number: 1- that the administrative courts look into the penalties directed at the employee from the administrant to the employee who has withdrawn the hand from his public office. especially in the penalties of dismissal and dismissal, provided that the appeal is mandatory either by the employee or by investigative committee to raise all the investigative papers and the penalty directed to the employee to the administrative court consider whether the punishment is correct or not, the two penalties mentioned above are among the most serious penalties that are applied to the employee. 2- He suggested to the civil service system, setting time to suspend the year from work and not to be dismissed because in this it generates the state treasury and harms the public employee who is suspended from work to receive half of his salaries and does not provide any community service.
- Published
- 2021
5. Perception of saudi college students on academic advising: A cross-sectional survey study
- Author
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Mohammad Khursheed Alam, Rakhi Issrani, Namdeo Prabhu, Ahmed Saad Assaf, Darrel Singh, and Arunpriya Srinivasan
- Subjects
Male ,Medical education ,Cross-sectional study ,media_common.quotation_subject ,education ,Rehabilitation ,Saudi Arabia ,Public Health, Environmental and Occupational Health ,Questionnaire ,Academic advising ,Cross-Sectional Studies ,Surveys and Questionnaires ,Perception ,Humans ,Female ,Research questions ,Students ,Psychology ,Female students ,Strengths and weaknesses ,media_common - Abstract
BACKGROUND: Academic advising is a central and essential element in the process of education that can help students unravel their academic problems and succeed in their academic and professional careers OBJECTIVES: To seek students’ perception about academic advising and solicit suggestions to improve academic advising in our institute. The specific objectives of the study were to assess the students’ satisfaction regarding academic advising guidance and to ascertain whether students’ perceptions of academic advising differ by their demographic characteristics and academic years. METHODS: A forty-item questionnaire was hand delivered to all the undergraduate (UG) students of College of Dentistry, Jouf University, Sakaka, Kingdom of Saudi Arabia. The research questions focused on demographic information, advising assistance and guidance, satisfaction, and suggestions to improve the effectiveness of the present academic advising system. Data analysis is presented through tables and descriptive methods. RESULTS: The samples consisted of 98 males and 43 females. Overall, the respondents were positive about academic advising services they received from their respective advisors. Female students felt more positive than male students for all the statements on academic advising (p
- Published
- 2020
6. Ultrasound-Energy Consumption During Phases of Phacoemulsification of Nuclear Cataracts Using Femtosecond Laser: A Comparative Study
- Author
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Ahmed Hassan Assaf and Bassem F Aziz
- Subjects
medicine.medical_specialty ,Nuclear cataract ,genetic structures ,business.industry ,medicine.medical_treatment ,Phacoemulsification ,Cataract surgery ,Subgroup B ,medicine.disease ,Subgroup C ,eye diseases ,03 medical and health sciences ,Ophthalmology ,Quadrant (abdomen) ,0302 clinical medicine ,Cataracts ,030221 ophthalmology & optometry ,medicine ,sense organs ,business ,Ultrasound energy ,030217 neurology & neurosurgery - Abstract
Purpose To compare ultrasound (US) energy utilized in different phases of nuclear cataract removal in femtosecond laser-assisted cataract surgery (FLACS) with conventional phacoemulsification surgery (CPS) in relation to different nuclear densities. Methods A prospective nonrandomized comparative study was conducted at Ain Shams University and Al Watany Eye Hospital, Cairo, Egypt on 250 eyes with senile nuclear cataracts (NCs) of different nuclear densities (1-6). Eyes were divided into two groups - FLACS and CPS - and each group was subdivided according to cataract density into subgroups A (NC 1-2), B (NC 3-4) and C (NC 5-6). sextant-softened fragmentation patterns were assessed in the FLACS group and the quick-chop technique used in the CPS group. US energy required for nucleus cracking (EFX split) and for quadrant removal (EFX quadrant) was recorded. Results Total eyes included in the FLACS and CPS groups were 117 and 133, respectively. No significant differences between the groups for EFX quadrant and EFX split groups were observed (P=0.18 and P=0.49, respectively). For subgroup A, no significant difference was found between FLACS and CPS on EFX split (P=0.08) and EFX quadrant (P=0.49). For subgroup B, significantly lower values of EFX split (P=0.0001) and EFX quadrant (P
- Published
- 2020
7. Thermodynamics of a Liquid Film in the Presence of External Shear Stress
- Author
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Ahmed Hassan Assaf and Sameh A. Alkharashi
- Subjects
Liquid film ,Materials science ,Mechanics of Materials ,Mechanical Engineering ,Shear stress ,Thermodynamics ,Condensed Matter Physics - Published
- 2020
8. Analysis of Ocular Cyclotorsion in Lying Position after Peribulbar Block
- Author
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Mohmmad Abd El Fattah Qabeel, Mona Mohammad El Fiky, Ahmed H.S. Assaf, and Jack Mikhael Zaki Mikhael
- Subjects
medicine.medical_specialty ,Peribulbar anesthesia ,Supine position ,genetic structures ,business.industry ,medicine.medical_treatment ,Peribulbar block ,Astigmatism ,Cataract surgery ,medicine.disease ,eye diseases ,medicine.anatomical_structure ,Ophthalmology ,Medicine ,Human eye ,Potential source ,sense organs ,business - Abstract
Background: Cyclotorsions are movements of cyclotorsion of the eyes. The cyclotorsion of the human eye occurs with movement of the head and body, changing the original position of the corneal axis. A significant different range of cyclotorsion between a lie and a supine position was previously reported as varying from 2 to 7 degrees. Aim of Study: The aim of this prospective study is to determine the amount of ocular cyclotorsion in supine position after peribulbar block, to avoid misalignment of the toric IOL which negates the desired effect of correcting astigmatism. Patients and Methods: A prospective observational rand-omized cross sectional study included a total of 50 eyes of 50 patients undergoing cataract surgery under peribulbar anaesthesia in El-Durrah Specialized Eye Centre, in the period from March 2018 to September 2018. Results: In this prospective series of 50 consecutive cases we observed that: The mean of cyclotorsion in the study after peribulbar block: Was (5.20±1.85 degrees), which was statis-tically significant greater than 0 degrees. Incyclotorsion appeared in 31 eyes (62%) and the mean of rotation was 5.77 degrees. Excyclotorsion ocurred in 16 eyes (32%) and the mean was 5.06 degrees. There were no cyclotorsion in 3 eyes. Cyclotorsion (1-5) degrees occurred in 27 eyes (48%). Cyclo-torsion more than 5 degrees occurred in 23 eyes (46%). Conclusion: Cyclotorsion represents another potential source of residual refractive errors that subsequently will lead to a reduced visual quality post-operatively. Therefore should be carefully taken into account in the pre-operative analyses.
- Published
- 2020
9. Correlation between Diabetic Macular Edema and Best Corrected Visual Acuity in Different Categories of Diabetic Retinopathy
- Author
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Elsayed A.A. Mohamed, Mouamen M.M. Seleet, Ahmed H.S. Assaf, and Ahmed Abdelmonsef Ebeid
- Subjects
education.field_of_study ,medicine.medical_specialty ,Visual acuity ,endocrine system diseases ,genetic structures ,Cross-sectional study ,business.industry ,Diabetic macular edema ,Population ,Diabetic retinopathy ,medicine.disease ,eye diseases ,Correlation ,Ophthalmology ,Diabetes mellitus ,medicine ,sense organs ,medicine.symptom ,education ,business ,Macular edema - Abstract
Background: Diabetic Retinopathy (DR) is a major cause of vision loss in the working age population and people with diabetes are 25 times more likely than the general population to go blind.Aim of Study: To correlate the Best-Corrected Visual Acuity (BCVA) by ETDRS protocol with macular thickness measurement and morphology as obtained by OCT in a series of patients with diabetic macular edema, with or without diabetic retinopathy.Patients and Methods: Cross sectional design, in total 102 of 51 selected Egyptian diabetic subjects, 20 males and 31 females were selected by convenient sample in the study during the period from Mars. 2018 to December 2018, all procedures were done at National Institute Of Diabetes And Endocrinology. Eyes enrolled in the study were divided into three groups as follows: Group 1: Eyes with DME and non clinically detectable DR, Group 2: Eyes with DME and NPDR, Group 3: Eyes with DME and PDR.Results: In the present study,we found that the Diffuse Spongy Macular Edema (DSME) was the most common type of DME, we found a highly significant negative correlation between the CMT and BCVA. There was a significant corre-lation between the OCT pattern of DME and the severity of diabetic retinopathy. We also found a statistically significant decrease in BCVA in eyes with PDR in comparison to eyes with NPDR and eyes with no clinically detectable diabetic retinopathy.Conclusion: Based on the data in our study, diffuse spongy macular edema was the most common type of DME with the least CMT and the highest BCVA, we also found the worst BCVA in PDR.
- Published
- 2019
10. MicroPulse® transscleral laser therapy in the management of glaucoma patients
- Author
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Amr Mohamed, ELGwaily, Shaker Ahmed, Khedrrrr, Ahmed Hassan, Assaf, Mahmoud A Meguid A Latif, Latif, Hassan Ahmad, Elsayed, and Ahmed A Meguid A Latif, Latif
- Abstract
To evaluate the efficacy and safety of MicroPulse® transscleral laser therapy (TLT) in the management of glaucoma patients.A prospective, interventional, non-comparative case series was conducted in the department of ophthalmology, Ain Shams University Hospital on 61 eyes of 46 patients with various glaucoma types and of severity, ranging from mild to severe. In addition to best-corrected visual acuity (BCVA), intraocular pressure (IOP) and the number of glaucoma medications were recorded before and after treatment, along with the postoperative need for systemic carbonic anhydrase inhibitors (CAI), success rates, number of treatment sessions and postoperative complications. Success was defined as an IOP of 6-18mmHg or at least a 30% decrease from preoperative IOP in the absence of any vision-threatening complications during the 6-month follow-up period.MicroPulse TLT was performed on 61 glaucomatous eyes. Eleven of the 61 eyes (18%) that did not achieve IOP between 6-18mmHg, or at least a 30% decrease from baseline at 6 months, had a repeat MicroPulse TLT session. At 6 months follow-up post a single MicroPulse TLT session, the mean IOP reduction was 35.9±14.2%; and 6 months after the second session, it was 36.2±17.5% (P.001). The success rate after the first session was 73.8% which increased to 78.7% after the second session. The mean anterior chamber (AC) cell reaction was+1.9±.8 at 1 day,+1.0±.7 at 1 week, and+.2±.4 at 1 month postoperatively. No cells were detected in any of the cases at 3 and 6 months follow-up (P.001). The average number of anti-glaucoma eye drops before MicroPulse TLT was 2.6±1.0. Postintervention, the average number of anti-glaucoma eye drops was 1.7±1.2, and sustained at 6 months follow-up after the last treatment session (P.001). There were no significant complications were noted. One eye developed transient hypotony for 3 months after MicroPulse TLT.MicroPulse TLT is safe and effective in lowering IOP in a variety of glaucoma types and severity.
- Published
- 2020
11. Ultrasound-Energy Consumption During Phases of Phacoemulsification of Nuclear Cataracts Using Femtosecond Laser: A Comparative Study
- Author
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Ahmed H, Assaf and Bassem F, Aziz
- Subjects
genetic structures ,femtosecond laser ,phacoemulsification ,sense organs ,cataract surgery ,eye diseases ,FLACS ,Original Research - Abstract
Purpose To compare ultrasound (US) energy utilized in different phases of nuclear cataract removal in femtosecond laser–assisted cataract surgery (FLACS) with conventional phacoemulsification surgery (CPS) in relation to different nuclear densities. Methods A prospective nonrandomized comparative study was conducted at Ain Shams University and Al Watany Eye Hospital, Cairo, Egypt on 250 eyes with senile nuclear cataracts (NCs) of different nuclear densities (1–6). Eyes were divided into two groups — FLACS and CPS — and each group was subdivided according to cataract density into subgroups A (NC 1–2), B (NC 3–4) and C (NC 5–6). sextant-softened fragmentation patterns were assessed in the FLACS group and the quick-chop technique used in the CPS group. US energy required for nucleus cracking (EFX split) and for quadrant removal (EFX quadrant) was recorded. Results Total eyes included in the FLACS and CPS groups were 117 and 133, respectively. No significant differences between the groups for EFX quadrant and EFX split groups were observed (P=0.18 and P=0.49, respectively). For subgroup A, no significant difference was found between FLACS and CPS on EFX split (P=0.08) and EFX quadrant (P=0.49). For subgroup B, significantly lower values of EFX split (P=0.0001) and EFX quadrant (P
- Published
- 2020
12. Visual Outcomes after Topography-Guided Femtosecond LASIK in Virgin Eyes
- Author
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Ahmed Hassan Assaf, Sameh Hany AbdEl Rahman, Mai Mohammad Zaki Afifi, and Mahmoud Abdel Meguid Abdel latif
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Keratoconus ,medicine.medical_specialty ,genetic structures ,business.industry ,medicine.medical_treatment ,LASIK ,Glaucoma ,Keratomileusis ,Astigmatism ,medicine.disease ,01 natural sciences ,eye diseases ,010309 optics ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,Refractive surgery ,0103 physical sciences ,030221 ophthalmology & optometry ,medicine ,sense organs ,Eye surgery ,business ,Dioptre - Abstract
Background: Laser vision correction has been established over the last 2 decades as a safe and effective intervention, with Laser-assisted in situ keratomileusis (LASIK), being one of the main techniques practiced globally. Femtosecond laser-assisted LASIK has become a popularized modification over the last decade and over the standard LASIK technique utilizing mechanical microkeratomes. A spherical ablation profiles performed by “wave front optimized” have been employed to reduce spherical aberration associated with myopic corrections. Aim of the Work: To evaluate the quality and efficacy of topography-guided femtosecond lasik in virgin eyes with myopia, hypermetropia and astigmatism. Patients and Methods: This comparative prospective study was conducted on 60 eyes of 30 Egyptian patients with comparing preoperative and postoperative outcomes. Eyes with myopia (-1.0 up to -8.0 diopters) or hypermetropia (+1.0 up to +5.0 diopters) or astigmatism (up to 5.0 diopters) or less. Eyes with central corneal thickness (CCT) of 500 microns or more. Eyes at risk for developing post-refractive corneal ectasia, such as keratoconus, keratoconus suspect, previous refractive surgery, corneal dystrophy, corneal guttae or opacities, any previous eye surgery e.g.:pseudophakic patients, retinal detachment surgery, all eyes were normal for example no cataract, no glaucoma, no retinal pathology and no previous trauma. Results: Our study was performed on sixty eyes of thirty Egyptian patients. Sixty eyes of thirty patients underwent LASIK using T-CAT. Seventeen patients were females and thirteen were males. The average age of the patients was 24.8 year ±5.45 standard deviation (SD). The average spherical error was -3.09 D ±2.33 SD. The average cylinder error was -1.02 D ±1.02 SD. Conclusion: The results showed that there were statistically significant differences between preoperative BCVA and postoperative UCVA with a good safety and efficacy profile with T-CAT lasik as no patient loss even one line and 80% of cases gaining at least one line postoperative. The surgery was associated with higher values of high order aberrations after surgery than before surgery.
- Published
- 2018
13. Posterior Corneal Astigmatism Changes in Cases with Keratoconus
- Author
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Mohammed Elsaid AbdElaziz Mahmoud, Ismael Ebraheem Hamza, Ahmed Hassan Assaf, and Tamer Fahmy Eliwa
- Published
- 2018
14. Study of Accuracy of Corneal Flap Thickness by Using Femtosecond Laser Technology
- Author
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George Adel Aziz Mansour, Bassem Fayez Aziz Riad, Ahmed Hassan Assaf, and Rania Gamal Eldin Zaky
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medicine.medical_specialty ,Distance visual acuity ,genetic structures ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Group ii ,LASIK ,Fundus (eye) ,Corneal topography ,eye diseases ,Laser technology ,Optical pachymetry ,Ophthalmology ,Femtosecond ,Medicine ,sense organs ,business - Abstract
Background- LASIK is the most popular surgery to correct the refractive errors nowadays. It is proved to be safe, effective and well predictable. It is important to produce a uniform flap with a narrow SD from the intended thickness. The Integrated optical pachymetry is a convenient and useful feature of the EX500 excimer laser which can be used to measure flap thickness intraoperatively.Objectives: this study aimed to detect the accuracy of Allegretto Wavelight FS200™ platform in creation of different corneal flap thicknesses. Patients and Methods: sixty eyes of 30 myopic patients were included in our study, the patients were operated by 2 different surgeons from June 2017 till December 2017. The patients were distributed randomly into 3 studied groups. Group I (20 eyes with intended fs flap 100um), group II (20 eyes with intended fs flap 110um) and group III (20 eyes with intended fs flap 120um). All participants were subjected to full medical history taking, uncorrected distance visual acuity, slit-lamp microscopy, corneal topography using oculus® pentacam device, manifest and cycloplegic refraction, corrected distance visual acuity, fundus bio-microscopy examination using 90 D lens. Results: inthis study 100μm thickness group (Group A) showed the lowest difference between the mean result and the intended flap (-0.35um) followed by the 120um group (Group C) with difference of (-2.9um) between the mean result and the intended flap thickness followed by the 110μm group (group B) with the highest difference (-3.45um) from the intended flap thickness. Conclusion: the flaps made with the Wavelight FS200 femtosecond laser were predictable and uniform more predictable in group A than in group C and B, but with no statistical significance between the three studied groups (P=0.402).
- Published
- 2018
15. Q Value Based Ablation Profile versus Topography - Guided LASIK : A Contralateral Comparative Study
- Author
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Ismail Ibrahim Hamza, Ahmed Hassan Assaf, Mohamed Tarek El Naggar, and Esraa Mohamed Abd El Monem
- Subjects
medicine.medical_specialty ,Visual acuity ,genetic structures ,Excimer laser ,business.industry ,media_common.quotation_subject ,medicine.medical_treatment ,LASIK ,Strehl ratio ,Coma (optics) ,Ablation ,eye diseases ,03 medical and health sciences ,0302 clinical medicine ,Refractive surgery ,Ophthalmology ,030221 ophthalmology & optometry ,medicine ,Contrast (vision) ,medicine.symptom ,business ,030217 neurology & neurosurgery ,media_common - Abstract
Background: laser in situkeratomileusis (LASIK) has become the most widely used form of refractive surgery. The objective of this surgical technique was to modify the anterior corneal shape by ablating tissue from the stroma by means of the excimer laser after creating a hinged corneal flap. By this way, we were able to change the refractive status of the patient and provided better unaided vision. Continuous improvements in the original technique made the surgical procedure safer, more accurate and repeatable. These progressions are due to the development of novel technologies that are responsible for new surgical instrumentation, which makes the surgical procedure easier for the surgeon and better excimer laser ablation algorithms, which increase the optical quality of the ablation and thus the safety of the vision correction procedure. Aim of work: the aim of this study was to compare between Q value based ablation and topography-guided LASIK as regards safety, visual acuity, contrast sensitivity and high order aberration HOAs (spherical, coma and trefoil). Patients and methods: this study was conducted on 60 eyes of 30 patients, thirty eyes of them underwent topography guided LASIK and the other 30 underwent Q value based ablation. Preoperative CDVA (corrected distant visual acuity) was done. Postoperative UDVA and CDVA were measured. Postoperative high order aberrations were measured 3 months postoperatively. Results: our results showed that there was no statistically significant difference between both groups as regards UDVA, spherical equivalent, high order aberrations and Strehl ratio point spread function. Conclusion: topographic guided ablation and Q value based groups provided essentially equivalent outcomes after myopic LASIK, with statistically insignificant difference between both profiles, although both laser profiles have been found to be effective, safe and predictable.
- Published
- 2018
16. Effective Phacoemulsification Time in Femto Cataract in Comparison to Conventional Cataract
- Author
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Rania Gamal Eldin Zaki, Ahmed Hassan Assaf, Marwa M. Mahmoud, and Yasmine Maher Mohammed
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education.field_of_study ,medicine.medical_specialty ,genetic structures ,business.industry ,medicine.medical_treatment ,Population ,Significant difference ,Phacoemulsification ,Cataract surgery ,Laser assisted ,medicine.disease ,eye diseases ,03 medical and health sciences ,0302 clinical medicine ,Cataracts ,Surgery procedure ,Ophthalmology ,030221 ophthalmology & optometry ,medicine ,sense organs ,education ,business ,Capsulorhexis ,030217 neurology & neurosurgery - Abstract
Background: Cataract surgery is one of the most commonly performed surgery in the world and the number of individuals with cataracts is predicted to reach 30 million by the year 20201. This number will continue to grow as the population ages. more and more patients pursue surgery at the early stage of cataract in order not to endure visual impairment. Phacoemulsification is the standard surgery procedure for cataract in the developed countries. In recent years, femtosecond laser (FSL) has been introduced into phacoemulsification cataract surgery to perform corneal incisions, capsulorhexis, and nuclear fragmentation. Numerous clinical studies have reported that using FSL to perform nuclear fragmentation before phacoemulsification significantly reduces the amount of ultrasound energy and effective phacoemulsification time (EPT) required in the surgery. Purpose: The goal of the present study is to assess the effect of FSL on effective phaco time in comparison to conventional phacoemusification procedure. Patients andMethods: a comparative study included 40 patients with senile cataract (nuclear cataract grade III or more) based on lens opacification classification system III (LOCSIII). The patients were subdivided into 2 groups; group (A) included 20 patients with senile cataract underwent Femtosecond laser-assisted phacoemulsification (CATALYS FSL system (Abbott Medical Optics)) and group (B) included 20 patients with senile cataract underwent conventional phacoemulsification ( INFINTI phacoemulsification platform (Alcon)). Effective phaco time had monitored and recorded in all patients. Results:As regarding conventional phaco group, mean EPT was 19.80±24.33 and in femto group, mean EPT was 1.05±1.28 with (p-value 0.001) which show highly significant difference between the two groups. Conclusion: Femto-second laser assisted cataract surgery reduce effective phacoemulsification time for grade 3 or more of nuclear cataract in comparison to manual procedure.
- Published
- 2017
17. Hydromagnetic instability of a thin viscoelastic layer on a moving column
- Author
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Sameh A. Alkharashi and Ahmed Hassan Assaf
- Subjects
Materials science ,Viscoelastic fluid ,Resonance ,Composite material ,Condensed Matter Physics ,Layer (electronics) ,Column (database) ,Instability ,Mathematical Physics ,Atomic and Molecular Physics, and Optics ,Viscoelasticity - Published
- 2019
18. Association between healthy eating index, body mass index, and early childhood caries in schoolchildren of Sakaka, KSA: A case–control study
- Author
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Mazen Nafa H. Alruwili, Anil Kumar Nagarajappa, Sudhakar Vundavalli, Ahmed Saad Assaf Aleiadah, Adel Saleh Alhabarti, and Radhika Doppalapudi
- Subjects
business.industry ,Saturated fat ,body mass index ,Overweight ,Anthropometry ,healthy eating index ,medicine.disease ,Obesity ,lcsh:RK1-715 ,stomatognathic diseases ,early childhood caries ,lcsh:Dentistry ,dental caries ,Medicine ,Population study ,medicine.symptom ,Underweight ,business ,dietary habits ,Body mass index ,Early childhood caries ,Demography - Abstract
Background: Early childhood caries (ECC) was observed in children worldwide, and it adversely affects the oral health-related quality of life. ECC is multifactorial, and the concepts of poor nutrition and inappropriate feeding bottle habits as its risk factors could not provide sufficient evidence. Aim: The study aimed to assess the relation between Healthy Eating Index (HEI), body mass index (BMI), and ECC in the age group of 5–6 years children. Materials and Methods: A case–control study was carried out among 350 schoolchildren of Sakaka, KSA. Caries experience was recorded using decayed, missing, and filled teeth (dmft) index (WHO criteria 1997); various anthropometric measures such as weight, BMI, and height were recorded as per the standard guidelines. The Pearson's correlation coefficient and unpaired t-tests were used as bivariate tests; ANOVA with Tukey's post hoc for multivariate analysis. Results: A total of 350 male participants participated in the study, with the age range of 5–6 years and the mean age being 5.4 ± 0.7. The prevalence of ECC in the study population was 87%. The mean dmft values for each BMI category among the underweight, normal, overweight, and obese children were 4.73, 7.8, 9.4, and 10.8, respectively. The mean intake of grains was 1.9, vegetables 0.61, fruits 1.31; milk 1.78, meat/dal 4.8, total fat 9.9, saturated fat 9.9, cholesterol 10 refined carbohydrates 10, and variety 0.17 in children with severe ECC (S-ECC). Overall mean HEI score was significantly higher in children with S-ECC compared to simple ECC low (43.25 ± 3.44 vs. 57.46 ± 4.12), and HEI and dmft values were negatively correlated (−0.932). Conclusion: There is a negative relationship between ECC and HEI scores and positive correlation between BMI scores and ECC. Diet is again proved as a common risk factor for dental caries and obesity. Hence, the Nutritional Education Program is the need of an hour for these children and parents.
- Published
- 2019
19. Indications of Pentacam in the Evaluation of Irregular Corneas
- Author
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Maged M Roshdy, Ahmed Hassan Assaf, and Sherein S. Wahba
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business.industry ,Medicine ,business - Published
- 2011
20. Directed Covering with Block Size 5 and Index Odd
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Ahmed M. Assaf, L. P. S. Singh, and H. Alhalees
- Subjects
Discrete mathematics ,Combinatorics ,Index (economics) ,Applied Mathematics ,Ordered pair ,Discrete Mathematics and Combinatorics ,Function (mathematics) ,Block size ,Mathematics - Abstract
A directed covering design, DC(v, k, λ), is a (v, k, 2λ) covering design in which the blocks are regarded as ordered k-tuples and in which each ordered pair of elements occurs in at least λ blocks. Let DE(v, k, λ) denote the minimum number of blocks in a DC(v, k, λ). In this paper the values of the function DC(v, 5, λ) are determined for all even integers v ≥ 5 and λ odd.
- Published
- 2002
21. Simultaneous corneal crosslinking and surface ablation combined with phakic intraocular lens implantation for managing keratoconus
- Author
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Ahmed Hassan Assaf and Ahmed Kotb
- Subjects
Adult ,Male ,medicine.medical_specialty ,Keratoconus ,Phakic Intraocular Lenses ,genetic structures ,Adolescent ,medicine.medical_treatment ,Riboflavin ,Visual Acuity ,Phakic intraocular lens ,Photorefractive Keratectomy ,Cornea ,Young Adult ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Humans ,In patient ,Statistical analysis ,Prospective Studies ,Phakic iol ,Analysis of Variance ,Photosensitizing Agents ,business.industry ,Corneal Topography ,Ablation ,medicine.disease ,eye diseases ,Photorefractive keratectomy ,Cross-Linking Reagents ,Photochemotherapy ,Female ,sense organs ,Collagen ,business ,After treatment ,Follow-Up Studies - Abstract
To assess the efficacy and stability of simultaneous topography-guided photorefractive keratectomy (PRK) and crosslinking (Athens protocol) followed by phakic intraocular lens (IOL) implantation for managing keratoconus. Ain-Shams University, Cairo, Egypt. Prospective non-randomized study. All patients underwent topography-guided PRK followed immediately by collagen crosslinking (Athens protocol), 2–4 months later, eyes were implanted with either an iris claw or an angle-supported phakic IOL. Statistical analysis was performed with SigmaPlot software version 11.0 (Systat Software, Inc.). This study evaluated 22 eyes of 14 patients. Follow-up interval was at least 6 months. A Veriflex phakic IOL was implanted in 14 eyes (63.6 %), and a Cachet phakic IOL was implanted in 8 eyes (36.4 %). The mean preoperative keratometric reading (45.57 ± 1.51 D) was significantly reduced at 3 months and at 6 months after treatment (43.82 ± 1.98 D, P
- Published
- 2014
22. Directed packing and covering designs with block size four
- Author
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Ahmed M. Assaf, Nabil Shalaby, and Jianxing Yin
- Subjects
Combinatorics ,Discrete mathematics ,Directed ,Minimum covering ,Discrete Mathematics and Combinatorics ,Block size ,Maximum packing ,Theoretical Computer Science ,Mathematics - Abstract
In this paper we improve and generalize the results of two earlier papers of Skillicorn. The maximum (minimum) number of blocks in a directed (v; 4 ;� ) packing (covering) designs are completely determined. c 2001 Elsevier Science B.V. All rights reserved.
- Published
- 2001
23. Modified group divisible designs with block size 4 and λ = 1
- Author
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Ruizhong Wei and Ahmed M. Assaf
- Subjects
Combinatorics ,Discrete mathematics ,Cyclotomic class ,Group (mathematics) ,Modified GDD ,Mod ,Discrete Mathematics and Combinatorics ,GDD ,PBD ,Block size ,Theoretical Computer Science ,Mathematics - Abstract
In this paper it is shown that the MGD[4,1, m, mn] exist when (m − 1)(n − 1) ≡ 1 (mod 3) and n, m ⩾ 4 with some possible exceptions.
- Published
- 1999
24. Constructions of optimal packing designs
- Author
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Jianxing Yin and Ahmed M. Assaf
- Subjects
Combinatorics ,Packing problems ,Integer ,Ordered pair ,Block (permutation group theory) ,Discrete Mathematics and Combinatorics ,Mathematics - Abstract
Let v and k be positive integers. A (v, k, 1)-packing design is an ordered pair (V, B) where V is a v-set and B is a collection of k-subsets of V (called blocks) such that every 2-subset of V occurs in at most one block of B. The packing problem is mainly to determine the packing number P(k, v), that is, the maximum number of blocks in such a packing design. It is well known that P(k, v) ≤ ⌊v⌊(v − 1)/(k − 1)⌋/k⌋ = J(k, v) where ⌊×⌋ denotes the greatest integer y such that y ≤ x. A (v, k, 1)-packing design having J(k, v) blocks is said to be optimal. In this article, we develop some general constructions to obtain optimal packing designs. As an application, we show that P(5, v) = J(5, v) if v ≡ 7, 11 or 15 (mod 20), with the exception of v ∈ {11, 15} and the possible exception of v ∈ {27, 47, 51, 67, 87, 135, 187, 231, 251, 291}. © 1998 John Wiley & Sons, Inc. J Combin Designs 6: 245–260, 1998
- Published
- 1998
25. Bilateral congenital vertical gaze disorders: congenital muscle fibrosis or congenital central nervous abnormality?
- Author
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Ahmed A. Assaf
- Subjects
Pediatrics ,medicine.medical_specialty ,Pathology ,Palsy ,business.industry ,Muscle disorder ,Extraocular muscles ,Gaze ,Pathophysiology ,Ophthalmology ,medicine.anatomical_structure ,Congenital Fibrosis Syndrome ,medicine ,Etiology ,Neurology (clinical) ,Abnormality ,business - Abstract
Congenital disorders of vertical gaze are uncommon and current terminology such as double elevator palsy, congenital fibrosis syndrome and congenital ocular motor palsy poorly reflect the underlying pathophysiology. Congenital fibrosis syndrome appears to be the most common of these disorders. We describe nine additional patients with congenital vertical motility restrictions who fit the descriptions of this syndrome. Six of the patients had positive family histories and came from consanguineous marriages. Numerous clinical features, including supranuclear disturbances of ocular motility, point to a central etiology rather than a primary muscle disorder, as 'congenital fibrosis syndrome' suggests.
- Published
- 1997
26. Comparative analysis of corneal morphological changes after transversal and torsional phacoemulsification through 2.2 mm corneal incision
- Author
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Maged M Roshdy and Ahmed Hassan Assaf
- Subjects
Corneal endothelium ,medicine.medical_specialty ,endothelium ,torsional phacoemulsification ,business.industry ,medicine.medical_treatment ,Ultrasound ,Intraocular lens ,Clinical Ophthalmology ,Phacoemulsification ,Cataract surgery ,Torsional phacoemulsification ,transversal phacoemulsification ,Endothelial cell density ,Ophthalmology ,medicine.anatomical_structure ,Cornea ,cornea ,Ellips™ FX ,medicine ,sense organs ,business ,OZil® IP ,Original Research - Abstract
Ahmed Assaf, Maged Maher RoshdyOphthalmology Department, Ain Shams University, Cairo, EgyptPurpose: This paper compares and evaluates the corneal morphological changes occurring after cataract surgery through a 2.2 mm corneal incision. We use two platforms for comparison and evaluation, transversal and torsional phacoemulsification.Patients and methods: This study includes 139 consecutive cataractous eyes (nuclear color 2–4, according to the Lens Opacities Classification System III [LOCSIII]) of 82 patients undergoing cataract surgery through a 2.2 mm corneal incision. Two different phacoemulsification platforms were used and assigned randomly: we used the WhiteStar Signature® system with the Ellips™ FX transversal continuous ultrasound (US) mode for group I (mean age: 65.33 ± 6.97 years), and we used the Infiniti® system with the OZil® Intelligent Phaco (IP) torsional US mode for group II (mean age: 64.02 ± 7.55 years). The corneal endothelium and pachymetry were evaluated preoperatively and at 1 month postoperatively. Incision size changes were also evaluated.Results: All surgeries were uneventful. Before intraocular lens implantation, the mean incision size was 2.24 ± 0.06 mm in both groups (P = 0.75). In terms of corneal endothelial cell density, neither preoperative (I vs II: 2304.1 ± 122.5 cell/mm2 vs 2315.6 ± 83.1 cell/mm2, P = 0.80) nor postoperative (I vs II: 2264.1 ± 124.3 cell/mm2 vs 2270.3 ± 89.9 cell/mm2, P = 0.98) differences between the groups were statistically significant. The mean endothelial cell density loss was 1.7% ± 1.6% and 2.0% ± 1.4% in groups I and II, respectively. Furthermore, no significant differences between groups I and II were found preoperatively (P = 0.40) and postoperatively (P = 0.68) in central pachymetry. With surgery, the mean increase in central pachymetry was 28.1 ± 23.6 µm and 24.0 ± 24.0 µm in groups I and II, respectively (P = 0.1).Conclusion: Ellips™ FX transversal and OZil® IP torsional phacoemulsification modes are safe for performing cataract surgery, inducing minimal corneal thickness and endothelial changes.Keywords: cornea, endothelium, transversal phacoemulsification, torsional phacoemulsification, Ellips™ FX, OZil® IP
- Published
- 2013
27. On covering designs with block size 5 and index 5
- Author
-
Ahmed M. Assaf
- Subjects
Combinatorics ,Discrete mathematics ,Integer ,Applied Mathematics ,Order (ring theory) ,Lambda ,Block size ,Computer Science Applications ,Mathematics - Abstract
LetV be a finite set of order υ. A (υ, κ, λ) covering design of index λ and block size κ is a collection of κ-element subsets, called blocks, such that every 2-subset ofV occurs in at least λ blocks. The covering problem is to determine the minimum number of blocks, α(υ, κ, λ), in a covering design. It is well known that\(\alpha \left( {\upsilon ,\kappa ,\lambda } \right) \geqslant \left\lceil {\tfrac{v}{\kappa }\left\lceil {\tfrac{{v - 1}}{{\kappa - 1}}\lambda } \right\rceil } \right\rceil = \phi \left( {\upsilon ,\kappa ,\lambda } \right)\), where [x] is the smallest integer satisfyingx≤[X]. It is shown here that α(υ, 5, 5)=ϕ(υ, 5, 5) for all positive integers υ≥5 with the possible exception of υ=24, 28, 56, 104, 124, 144, 164, 184.
- Published
- 1995
28. Bipacking pairs by quintuples: The case ν≡13 (mod 20)
- Author
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Ahmed M. Assaf
- Subjects
Discrete mathematics ,Combinatorics ,Packing problems ,Mod ,Discrete Mathematics and Combinatorics ,Order (group theory) ,Block size ,Theoretical Computer Science ,Mathematics - Abstract
A ( ν , κ , λ ) packing design of order ν, block size κ, and index λ is a collection of κ-element subsets, called blocks, of a ν-set V such that every 2-subset of V occurs in at most λ blocks. The packing problem is to determine the maximum number of blocks in a packing design. Packing with λ =2 is called bipacking. In this paper we solve the bipacking problem in the case κ =5 and ν ≡13 ( mod 20).
- Published
- 1994
29. Packing pairs by quintuples with index 2: v odd, v ≢ 13 (mod 20)
- Author
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Ahmed M. Assaf and L. P. S. Singh
- Subjects
Combinatorics ,Discrete mathematics ,Packing problems ,Mod ,Order (group theory) ,Discrete Mathematics and Combinatorics ,Block size ,Mathematics ,Theoretical Computer Science - Abstract
A (v, k, λ) packing design of order v, block size k, and index λ is a collection of k-element subsets, called blocks, of a v-set, V, such that every 2-subset of V occurs in at most λ blocks. The packing problem is to determine the maximum number of blocks in a packing design. In this paper we provide a powerful technique for constructing designs and solve the packing problem with k = 5, λ = 2, and all odd numbers v, v ≢ 13 (mod 20), with the possible exception of v = 19, 27, 137, 139, 147.
- Published
- 1994
- Full Text
- View/download PDF
30. Early versus late alignment of infantile esotropia
- Author
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Ahmed A. Assaf
- Subjects
medicine.medical_specialty ,genetic structures ,business.industry ,Surgical correction ,Surgical procedures ,medicine.disease ,eye diseases ,Surgery ,Infantile esotropia ,Ophthalmology ,medicine ,Prism diopters ,Strabismus ,business ,Binocular vision ,Esotropia - Abstract
Fifty-two children with infantile esotropia had surgery for their esotropia between two and seven years of age. Another 49 had similar surgery before the age of two years. Of these 101 operated children, the esotropia in 70 patients was aligned to within 10 prism diopters. The patients with successful alignment were reviewed to study the effect of early versus late surgical intervention of their deviation, i.e. before and after two years of age. The motor and sensory states of the selected patients were analysed before and after surgical correction. The choice and number of surgical procedures employed are discussed. It appears that patients two years and older when strabismus was surgically corrected have a good chance of alignment, but less chance of attaining binocularity. In many cases there was a V-pat-tern esotropia, requiring surgery on the overacting inferior oblique muscles. In comparison, the younger group with earlier surgery appeared to show a better chance of attaining binocularity and fewer patients had significant V-pattern requiring surgery on the inferior oblique muscles.
- Published
- 2011
31. Covering pairs by quintuples with index λ 0 (mod 4)
- Author
-
Ahmed M. Assaf
- Subjects
Combinatorics ,Discrete mathematics ,Integer ,Mod ,Discrete Mathematics and Combinatorics ,Order (group theory) ,Mathematics - Abstract
A (v, k. λ) covering design of order v, block size k, and index λ is a collection of k-element subsets, called blocks, of a set V such that every 2-subset of V occurs in at least λ blocks. The covering problem is to determine the minimum number of blocks, α(v, k, λ), in a covering design. It is well known that , where [χ] is the smallest integer satisfying χ ≤ χ. It is shown here that α (v, 5, λ) = ϕ(v, 5, λ) + ϵ where λ ≡ 0 (mod 4) and e= 1 if λ (v−1)≡ 0(mod 4) and λv (v−1)/4 ≡ −1 (mod 5) and e= 0 otherwise With the possible exception of (v,λ) = (28, 4). © 1993 John Wiley & Sons, Inc.
- Published
- 1993
32. Cataracts in glucose-6-phosphate dehydrogenase deficiency
- Author
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Ahmed A. Assaf, Mohsen A. F. El-Hazmi, and Khalid F. Tabbara
- Subjects
Adult ,Male ,Systemic disease ,medicine.medical_specialty ,Erythrocytes ,Adolescent ,genetic structures ,Presenile cataracts ,Physiology ,Deficiency state ,Cataract ,Cataracts ,Internal medicine ,Lens, Crystalline ,medicine ,Humans ,Child ,Genetics (clinical) ,Juvenile cataract ,business.industry ,Infant ,medicine.disease ,eye diseases ,Pedigree ,Ophthalmology ,Glucosephosphate Dehydrogenase Deficiency ,Phenotype ,Endocrinology ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Congenital cataracts ,Female ,sense organs ,business ,Glucose-6-phosphate dehydrogenase deficiency - Abstract
Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency plays an important biochemical role in the metabolism of the lens. Controversies exist in the literature on the possible association between G-6-PD deficiency and the development of cataracts. The authors present ten patients, aged between infancy and 40 years of age, who were admitted for bilateral congenital or presenile cataracts. These patients had no ocular or systemic disease which might have caused their cataract. The only systemic finding they had was G-6-PD deficiency. Two other patients among the families described suffered from bilateral congenital or presenile cataracts with no G-6-PD deficiency. This deficiency state does not appear to play a role in the production of their cataracts.
- Published
- 1993
33. Ocular aberrations and visual performance with an aspheric single-piece intraocular lens: contralateral comparative study
- Author
-
Ahmed Hassan Assaf and Ahmed Kotb
- Subjects
Male ,medicine.medical_specialty ,Visual acuity ,Corneal Wavefront Aberration ,genetic structures ,Pseudophakia ,Mesopic vision ,medicine.medical_treatment ,media_common.quotation_subject ,Vision Disorders ,Visual Acuity ,Coma (optics) ,Intraocular lens ,Prosthesis Design ,Contrast Sensitivity ,Lens Implantation, Intraocular ,Ophthalmology ,Surveys and Questionnaires ,medicine ,Contrast (vision) ,Humans ,Prospective Studies ,media_common ,Aged ,Lenses, Intraocular ,Phacoemulsification ,medicine.diagnostic_test ,business.industry ,Corneal Topography ,Corneal topography ,eye diseases ,Sensory Systems ,Spherical aberration ,Optometry ,Surgery ,Female ,sense organs ,medicine.symptom ,business - Abstract
To study spherical aberration, coma, and trefoil after implantation of a single-piece aspheric Tecnis intraocular lens (IOL) in cataract patients and the influence on photopic and mesopic contrast sensitivity.Ophthalmology Department, Ain-Shams University Hospitals, Cairo, Egypt.In this randomized prospective contralateral comparative study, patients had bilateral senile cataract. Eyes with a pathological condition other than cataract that might influence postoperative visual function were excluded. The aspheric IOL was compared with the Sensar AR40e spherical IOL. The IOL selection was randomized. Study criteria included corrected distance visual acuity (CDVA), wavefront aberrometry, and contrast visual acuity.Fifty-six eyes of 28 patients were enrolled. All patients completed the 2-month postoperative visit. There was no significant difference between the IOLs in CDVA (P.05). Ocular spherical aberration was significantly lower with aspheric IOLs than spherical IOLs (P.001). Two months after surgery, eyes with the aspheric IOL had better photopic contrast sensitivity and better mesopic contrast sensitivity at all cycles per degree. There was no significant difference in 3rd-order aberrations (coma and trefoil) between IOLs.After cataract surgery, the single-piece aspheric IOL resulted in significantly lower ocular spherical aberration and significantly better mesopic contrast sensitivity. No significant difference in 3rd-order aberrations indicates that both IOLs had satisfactory centration in the capsular bag.
- Published
- 2010
34. Packing designs with block size 6 and index 5
- Author
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Nabil Shalaby, Alan Hartman, and Ahmed M. Assaf
- Subjects
Combinatorics ,Discrete mathematics ,Packing problems ,Order (group theory) ,Discrete Mathematics and Combinatorics ,Block size ,Block design ,Mathematics ,Theoretical Computer Science - Abstract
A (v, к, λ) packing design of order v, block size к and index λ is a collection of к-element subsets, called blocks, of a v-set V such that every 2-subset of V occurs in at most λ blocks. The packing problem is to determine the maximum number of blocks in a packing design. The only previous work on the packing problem with к=6 concerns itself with the cases where the maximum packing design is in fact a balanced incomplete block design. In this paper we solve the packing problem with к=6 and λ=5 and all positive integers v with the possible exceptions of v=41, 47, 53, 59, 62, 71.
- Published
- 1992
- Full Text
- View/download PDF
35. Feasibility of bimanual microincision phacoemulsification in hard cataracts
- Author
-
Ahmed Hassan Assaf and A M El-Moatassem Kotb
- Subjects
Male ,medicine.medical_specialty ,Microsurgery ,genetic structures ,medicine.medical_treatment ,Eye disease ,Intraocular lens ,Cataract ,Intraoperative Period ,Cataracts ,Lens Implantation, Intraocular ,Hardness ,Ophthalmology ,Occlusion ,medicine ,Humans ,Prospective Studies ,Therapeutic Irrigation ,Aged ,Intraoperative Care ,Phacoemulsification ,business.industry ,Ultrasound ,Middle Aged ,medicine.disease ,eye diseases ,Thermal burn ,Surgery ,Treatment Outcome ,Feasibility Studies ,Female ,sense organs ,business ,Surgical incision - Abstract
The purpose of this work was to assess the feasibility of bimanual phacoemulsification in hard cataracts of N3+ using WhiteStar technology of Soveriegn (Advanced Medical Optics, Santa Ana, CA, USA). Ain-Shams University Hospitals, Ophthalmology Department, Cairo, Egypt. A randomized prospective noncomparative study. A randomized prospective study of 33 consecutive cases (N3+ or more) was conducted, phacoemulsification using a bimanual microincision technique using the Sovereign with WhiteStar technology phacoemulsification machine. One phaco mode was used in all eyes. The ultrasound power was set at 30–25% according to the hardness of the nuclei, duty cycle of 33%, flow rate of 20–28 cm3/min, and vacuum of 240 mmHg. Occlusion mode was on. Nine eyes received rollable intraocular lenses (IOL) of ThinOptx, whereas 24 eyes had been implanted with hydrophobic acrylic foldable IOL (Sensar OptiEdge SA40e of AMO) through a third incision. Study parameters were effective phacotime (EPT), presence of wound burn, degree of immediate postoperative iritis, amount of infusion solution used, and total operating time. The mean EPT was 4.3 s with an average ultrasound used of 5.7%. The mean operating time was 11 min and 20 s. Although the nuclear hardness was of grade 3 or above (in a scale of 5), there were no cases of thermal burn; P=0.005. Only three eyes suffered postoperative iritis 2+, which resolved within 1 week on topical steroids, statistically nonsignificant, P=0.2. The amount of infusion solution was less than that used in conventional coaxial phaco. This technique induced considerably less corneal astigmatism than surgery using conventional corneal incisions. Hard cataracts of N3 or more could be safely removed through an incision of 1.4 mm incision using bimanual micro-phaco.
- Published
- 2006
36. Optokinetic nystagmus testing using personal computers
- Author
-
Ahmed A. Assaf
- Subjects
medicine.medical_specialty ,genetic structures ,Optokinetic reflex ,Audiology ,Standard methods ,Nystagmus, Pathologic ,Ophthalmology ,Microcomputers ,Nystagmus, Physiologic ,Visual function ,Visual assessment ,medicine ,Humans ,Diagnosis, Computer-Assisted ,Psychology ,Software ,Optometry - Abstract
Optokinetic nystagmus (OKN) testing is a useful tool for visual assessment. It has been used for assessing visual function in infants, hysterical patients, and malingerers. It is also of value in the diagnosis of disorders of the central nervous system. At present the devices used for the clinical testing of OKN are the OKN drum and OKN tape. A method is presented for OKN testing using an IBM-personal computer or compatible. This method is compared with the other two standard methods.
- Published
- 1991
37. The Sensitive Period for Strabismic Amblyopia
- Author
-
Ahmed A. Assaf
- Subjects
Ophthalmology ,medicine.medical_specialty ,business.industry ,Period (gene) ,medicine ,Strabismic amblyopia ,business - Published
- 1993
38. Resolvable Group Divisible Designs with Block Size 3
- Author
-
Ahmed M. Assaf and Alan Hartman
- Published
- 1989
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