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Dive into the research topics where Abdulrahman M. Al-Muammar is active.

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Featured researches published by Abdulrahman M. Al-Muammar.


Acta Ophthalmologica | 2013

Prognostic factors for clinical outcomes in patients with Vogt-Koyanagi-Harada disease treated with high-dose corticosteroids

Ahmed M. Abu El-Asrar; Mamdouh Al Tamimi; Suhail Hemachandran; Hani S. Al-Mezaine; Abdulrahman M. Al-Muammar; Dustan Kangave

Purpose:  To determine prognostic factors in patients with Vogt–Koyanagi–Harada (VKH) disease who were treated with high‐dose corticosteroids.


Acta Ophthalmologica | 2012

The outcomes of mycophenolate mofetil therapy combined with systemic corticosteroids in acute uveitis associated with Vogt–Koyanagi–Harada disease

Ahmed M. Abu El-Asrar; Suhail Hemachandran; Hani S. Al-Mezaine; Dustan Kangave; Abdulrahman M. Al-Muammar

Purpose:  To study the effectiveness of mycophenolate mofetil (MMF) as first‐line therapy combined with systemic corticosteroids in acute uveitis associated with Vogt–Koyanagi–Harada (VKH) disease. The outcomes in this group were compared with those of another group of patients with VKH disease who were treated with corticosteroid monotherapy or with delayed addition of immunomodulatory therapy.


Journal of Ophthalmology | 2014

Genetics of Keratoconus: Where Do We Stand?

Khaled K. Abu-Amero; Abdulrahman M. Al-Muammar; Altaf A. Kondkar

Keratoconus is a progressive thinning and anterior protrusion of the cornea that results in steepening and distortion of the cornea, altered refractive powers, and reduced vision. Keratoconus has a complex multifactorial etiology, with environmental, behavioral, and multiple genetic components contributing to the disease pathophysiology. Using genome-wide and candidate gene approaches several genomic loci and genes have been identified that highlight the complex molecular etiology of this disease. The review focuses on current knowledge of these genetic risk factors associated with keratoconus.


Ophthalmic Genetics | 2015

Analysis of the SOD1 Gene in Keratoconus Patients from Saudi Arabia

Abdulrahman M. Al-Muammar; Hatem Kalantan; Taif Anwar Azad; Tahira Sultan; Khaled K. Abu-Amero

Abstract We investigated Saudi patients with familial and sporadic Keratoconus for mutations in the Superoxide dismutase 1, soluble (SOD1) gene. We sequenced the entire coding region, exon-intron boundaries and intron 2 encompassing a 7-bp deletion in clinically confirmed Keratoconus patients (n = 55) and 100 ethnically matched healthy controls. All cases and controls were unrelated. Sequencing the SOD1 gene revealed the presence of four nucleotide changes and all were non-coding. Those were g.12035 C > A; g.13978 T > A; g.12037 G > A and g.11931 A > C with similar frequencies in patients and controls. All four sequence changes were benign polymorphisms with no apparent clinical significance. Additionally, the 7-bp deletion in intro2 reported previously, were not detected in any of our Keratocnus cohort. In our Keratoconus cohort, no pathogenic SOD1 mutation(s) was identified.


Journal of Refractive Surgery | 2006

Topography-guided CATz versus conventional LASIK for myopia with the NIDEK EC-5000 : A bilateral eye study

Mansoor A Farooqui; Abdulrahman M. Al-Muammar

PURPOSE To evaluate the difference in visual acuity, subjective night vision glare, and higher order aberrations in eyes with myopia with or without astigmatism operated with topography-guided customized corneal LASIK and conventional LASIK. METHODS This contralateral study includes 46 eyes (23 patients) that underwent topography-guided corneal customized LASIK using the customized aspheric treatment zone (CATz) ablation profile in one eye and conventional LASIK using the NIDEK EC-5000 Advanced Vision Excimer laser system (NAVEX) in the other eye for myopia with or without astigmatism. Patients were masked to which eye underwent topography-guided CATz or conventional LASIK. Postoperative glare and root-mean-square (RMS) values for total higher order aberrations were measured at 1 and 3 months and compared between the two eyes. RESULTS No significant difference was noted in uncorrected visual acuity between the two groups at 1 and 3 months postoperatively. Of all patients, 81% stated glare was higher in conventionally treated eyes than in the CATz-treated eyes at 1 and 3 months postoperatively. The RMS values for total coma (0.2385 vs 0.1522) and spherical aberration (0.2381 vs 0.1058) in conventionally treated and CATz-treated eyes were significantly higher in conventionally treated eyes (P=.029 and P=.004, respectively) at 3-month follow-up. CONCLUSIONS Topography-guided corneal customized LASIK with the CATz profile gave better night vision quality as compared to conventional LASIK with expanded treatment zone. Better night vision quality was associated with less induced spherical aberrations and coma postoperatively in the CATz treatment group.


Investigative Ophthalmology & Visual Science | 2014

Mitochondrial sequence changes in keratoconus patients.

Khaled K. Abu-Amero; Taif Anwar Azad; Hatem Kalantan; Tahira Sultan; Abdulrahman M. Al-Muammar

PURPOSE We investigated whether a group of patients with keratoconus (KTCN) harbor mutations in the mitochondrial genome. METHODS We sequenced the full mitochondrial genome in a group of Saudi patients with KTCN (n = 26) and 100 ethnically matched controls who had no KTCN by examination. RESULTS A total of 10 KTCN patients (38.5%) had potentially pathogenic nonsynonymous mtDNA mutations. Of the nonsynonymous sequence changes detected, 4 (40%) were in Complex I, one was in the tRNA(Glutamine), one was in tRNA(Tryptophan), one was in tRNA(Asparagine), one was in tRNA(Histidine), and two were in the tRNA(Leucine2). One nonsynonymous sequence change was heteroplasmic, whereas all the remaining 9 were homoplasmic. These sequence changes were not detected in controls of similar ethnicity. Four sequence changes were novel (were not reported previously) and 5 were reported previously. Additionally, we detected 54 synonymous (does not result in an amino acid change) sequence changes with no pathologic significance. CONCLUSIONS If our results are confirmed in a larger cohort and multiple ethnicities, then mtDNA mutation may be considered as a genetic risk factor contributing indirectly through the oxidative stress mechanism to the development and/or progression of KTCN.


BioMed Research International | 2015

Screening of the Seed Region of MIR184 in Keratoconus Patients from Saudi Arabia

Khaled K. Abu-Amero; Inas Helwa; Abdulrahman M. Al-Muammar; Shelby Strickland; Michael A. Hauser; R. Rand Allingham; Yutao Liu

Micro-RNAs (miRNAs) are regulators of gene expression that control various biological processes. The role of many identified miRNAs is not yet resolved. Recent evidence suggests that miRNA mutations and/or misexpression may contribute to genetic disorders. Point mutations in the seed region of MIR184 have been recently identified in Keratoconus (KC) patients with or without other corneal and lens abnormalities. We investigated mutations within MIR184 in KC patients from Saudi Arabia and examined the relative expression of miR-184 and miR-205 in human cornea. Ethnically matched KC cases (n = 134) were recruited and sequencing was performed using PCR-based Sanger sequencing and analyzed using the Sequencher 5.2 software. Expression of miR-184 and miR-205 was profiled in postmortem unaffected ocular tissues obtained from donors with no history of ocular diseases. miR-184 expression was 15-fold higher than that of miR-205 in cornea samples. No mutation(s) within the screened genomic region of MIR184 in KC cases was detected. This suggests that mutation in MIR184 is a rare cause of KC alone and may be more relevant to cases of KC associated with other ocular abnormalities. The increased expression of miR-184 versus miR-205 in normal cornea samples implies a possible role of miR184 in cornea development and/or corneal diseases.


Investigative Ophthalmology & Visual Science | 2014

Association of mitochondrial haplogroups H and R with keratoconus in Saudi Arabian patients.

Khaled K. Abu-Amero; Taif Anwar Azad; Tahira Sultan; Hatem Kalantan; Altaf A. Kondkar; Abdulrahman M. Al-Muammar

PURPOSE Keratoconic corneas exhibit more mitochondrial DNA (mtDNA) damage than do normal corneas and thus mtDNA may represent a potential candidate for genetic susceptibility studies in keratoconus. To test this hypothesis we determined mitochondrial haplogroups in Saudi patients with keratoconus and healthy controls of same ethnicity. METHODS Mitochondrial haplogrouping was performed by polymerase chain reaction-based automated Sanger sequencing in 114 patients with keratoconus and 552 healthy controls. RESULTS Mitochondrial haplogroups H and R were significantly overrepresented in patients with keratoconus (28.9% vs. 8.5%, P < 0.0001 and 17.5% vs. 3.1%, P < 0.0001, respectively) as compared to healthy controls. CONCLUSIONS Our data suggest that individuals with mitochondrial haplogroups H and R are at increased risk to develop keratoconus. In addition, the results provide further evidence for a plausible role of mtDNA in keratoconus etiology.


International Ophthalmology | 2010

Vogt–Koyanagi–Harada disease occurring during interferon-alpha and ribavirin therapy for chronic hepatitis C virus infection

Abdulrahman M. Al-Muammar; Tariq M. Al-Mudhaiyan; Mohammed F. Al Otaibi; Ayman A. Abdo; Ahmed M. Abu El-Asrar

We report a case of Vogt–Koyanagi–Harada (VKH) disease in a 30-year-old patient who was receiving interferon-alpha and ribavirin therapy for chronic hepatitis C virus infection. The intraocular inflammation responded to systemic corticosteroid and mycophenolate mofetil treatment. Physicians should be aware of the association between interferon-alpha and ribavirin therapy for hepatitis C virus infection and the development of VKH disease.


Ocular Immunology and Inflammation | 2015

Long-term Evaluation of Efficacy and Safety of Deep Sclerectomy in Uveitic Glaucoma

Saleh A. Al Obeidan; Essam A. Osman; Ahmed Mousa; Abdulrahman M. Al-Muammar; Ahmed M. Abu El-Asrar

Abstract Purpose: To assess long-term efficacy and safety of deep sclerectomy (DS) in uveitic glaucoma. Patients and methods: Thirty-three consecutive eyes (21 patients) with uveitic glaucoma underwent DS with mitomycin C and implant. Goniopuncture (GP) was done for uncontrolled postoperative intraocular pressure (IOP). Results: Mean (±SD) follow-up was 33.2 (±19.8) months. IOP was reduced from a mean preoperative value of 37.2 to postoperative value of 14.7 mmHg (p < 0.0001). Complete success was achieved in 24/33 eyes (72.7%); qualified success was obtained in 7/33 eyes (21.2%). Neodymium:YAG GP was performed in 12 eyes. Postoperative complications included cataract progression in 9 eyes, transient hypotony in 6 eyes, shallow choroidal effusions in 4 eyes, hypotony with persistent maculopathy in 1 eye, hyphema in 1 eye, and decompression retinopathy in 1 eye. Conclusion: DS is safe and effective in patients with uveitic open-angle glaucoma. However, laser goniopuncture is frequently needed to improve the outcome.

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Yutao Liu

Georgia Regents University

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