Ümit Beden
Ondokuz Mayıs University
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Featured researches published by Ümit Beden.
Ocular Immunology and Inflammation | 2003
Ümit Beden; Murat Irkec; Diclehan Orhan; Mehmet Orhan
Purpose: The etiopathogenesis of pterygia is controversial. We wished to explore the effects of inflammatory cells and mediators such as T-lymphocyte subpopulations (CD4 and CD8), mast cells, intercellular adhesion molecule-1 (ICAM-1), and HLA-DR receptors on pterygium development. Methods: Immunohistochemical stainings were performed for T-lymphocyte subpopulations,mast cells, ICAM-1, and HLA-DR on sections of pterygium specimens. Nasal bulbar conjunctival specimens of patients undergoing cataract or vitrectomy operations were used for comparision. The mean number of mast cells/mm 2 was calculated using an ocular grid, and the difference between the numbers derived from pterygium and from normal conjunctival sections was analyzed statistically using the Mann-Whitney U test. CD4 and CD8 lymphocytes in the epithelial and subepithelial regions, and ICAM-1 and HLA-DR expression on pterygium epithelium were compared qualitatively. Results: Increased CD4 and CD8 lymphocytic infiltration in pterygium sections was observed. Only occasional lymphocytes were detected in normal conjunctival sections. The CD4/CD8 ratio was 0.33 for pterygium epithelium and 1.34 for pterygium substantia propria. Increased HLA-DR and scattered ICAM-1 expression were also detected on pterygium epithelium, but not on the normal conjunctival epithelium. The difference in mast cell numbers between the pterygium and control groups was not statistically significant. Conclusions: The detection of T-lymphocyte infiltration and ICAM-1 and HLA-DR expression in pterygium epithelium strongly supports the suggestion that cellular immunity plays an important role in pterygium formation. Pterygium epithelium also seems to participate actively in the augmentation of this inflammatory process by expressing ICAM-1 and HLA-DR molecules. Mast cells may participate in some stages or subtypes of pterygium during its development.
Ophthalmic Surgery Lasers & Imaging | 2012
Volkan Yeter; Baris Sonmez; Ümit Beden
BACKGROUND AND OBJECTIVE To compare the central corneal thickness (CCT) measurements by Galilei Dual-Scheimpflug analyzer (GSA) (Ziemer Group, Port, Switzerland) and ultrasound pachymeter (UP) in myopic eyes. PATIENTS AND METHODS In this prospective study, CCT of 161 myopic eyes of 81 refractive surgery candidates (35 female, 46 male; mean age: 23.18 ± 4.08 years) were measured by GSA and UP consecutively. The data were analyzed statistically by paired t test, Bland-Altman plot, and Pearson correlation test to assess the agreement of the measurements. RESULTS The mean CCTs obtained by GSA and UP were 559.85 ± 30.87 and 560.41 ± 34.45 μm, respectively. No significant difference was found between the measurements (P = .684) and regression analysis showed a high correlation between the measurements obtained with both devices (r = 0.86; P < .001). A strong agreement between the two methods was also found by Bland-Altman plot. CONCLUSION In myopic eyes, the CCT measurements of GSA and UP are similar and highly correlated. Because of high agreement between these devices, the GSA is a non-contact method that may be an alternative to UP for measurement of CCT.
European Journal of Ophthalmology | 2008
Ümit Beden; Ozarslan Y; Oztürk He; Sönmez B; Dilek Erkan; İhsan Öge
Purpose To establish normal exophthalmometry values in the adult Turkish population, and the impact of age, gender, interpupillary distance, Hertel base selection, and refractive status on globe position. Methods Exophthalmometry measurements and refractive status of 2477 subjects were conducted in one tertiary and five primary health care centers. Change of globe position by age, intersex differences in terms of globe position, correlations of Hertel base with exophthalmometry results, and interpupillary distance (IPD) were evaluated. Multiple linear regression analysis was performed to test determination effect of each variable on final Hertel reading. Results Median Hertel reading was 13 mm, and 95% of the population had an upper limit of 17 mm for both eyes. There was a negative correlation between spherical equivalent of refractive status and exophthalmometry results and a weak positive correlation between IPD and exophthalmometry result. Mean Hertel value was found to decrease significantly after the third decade. Hertel base value was found to have moderate linear correlation with Hertel results. A weak correlation was detected with Hertel base/IPD ratio with final Hertel results. Multiple linear regression analysis was performed and only 13% and 20% of change in Hertel values bilaterally were found to be determined by other variables (age, IPD, refractive status, and Hertel base value) for females and males. Conclusions Normative dataset for exophthalmometry results of the Turkish population is established to be used in clinical practice and research. Only 13% to 20% of change in Hertel values was detected to be determined by age, IPD and Hertel base values.
Cornea | 2011
Baris Sonmez; Ümit Beden
Purpose: To report the use of fibrin tissue glue in securing the keratolimbal allograft (KLAL) and living-related conjunctival limbal allograft to the ocular surface in patients with severe ocular chemical injury. Design: A retrospective review of interventional case series. Methods: Conjunctival limbal allografts were harvested from the first-degree living-related relatives under topical anesthesia and fixated to the superior and inferior limbal quadrants in the recipient eye. The KLALs were fixated mainly to the nasal and temporal limbus with the help of fibrin tissue glue after being cut into 2 crescents and manually dissected to near one-third thicknesses in a lamellar fashion. Results: Five eyes of 4 patients were included in the study. The sources of the chemical injuries were: CaOH2 (3 eyes), NaOH (1 eye), and mitomycin C (1 eye). The limbal stem cell deficiency was 360 degrees in 4 eyes and 300 degrees in 1 eye. Corneas were covered with conjunctiva or fibrovascular tissue adjacent to the areas with limbal stem cell deficiency. The fibrin tissue glue was effective in securing both the keratolimbal and the conjunctivolimbal grafts at the surgery. Postoperatively, the corneal epithelium healed within 1 week in all of the eyes. Neither graft dislocation nor graft rejection occurred after a mean of 18.2 months of follow-up. Conclusions: The use of fibrin glue to fixate the KLAL and the living-related conjunctival limbal allograft in patients with severe chemical trauma is practical and effective. This technique may also be beneficial in terms of decreasing the risk of rejection in this patient group.
Ophthalmic Plastic and Reconstructive Surgery | 2008
Bülent Yazc; Ümit Beden
Purpose: To evaluate the effect of instillation of a specific α2–adrenergic agonist, topical 0.5% apraclonidine solution, on upper eyelid position in patients with blepharoptosis. Methods: This study included 45 eyelids of 35 adult patients with blepharoptosis. Of these, 37 eyelids had acquired ptosis and 8 had congenital ptosis. Palpebral fissure height and margin-reflex distance in the upper eyelid were measured before and after instillation of 0.5% apraclonidine, 2.5% phenylephrine, and both drugs. Results: After instillation of 2.5% phenylephrine, 0.5% apraclonidine, and both drugs, the mean increases in palpebral fissure height were 2.12 mm ± 1.4 mm, 2.11 mm ± 1.4 mm, and 2.26 mm ± 1.3 mm, respectively, and the mean increases in margin-reflex distance were 1.93 mm ± 1.2 mm, 1.89 mm ± 1.3 mm, and 2.03 mm ± 1.2 mm, respectively (p = 0.86 and p = 0.85). The apraclonidine solution did not alter the test results in 14 eyelids in which the phenylephrine test results were negative. Conclusions: Topical 0.5% apraclonidine solution can be as effective as topical 2.5% phenylephrine in elevating a ptotic upper eyelid, and may be used for preoperative evaluation of blepharoptosis. Combined use of both drugs may not provide any additional benefit.
Ophthalmic Surgery and Lasers | 2005
Yuksel Sullu; Hesham Alotaiby; Ümit Beden; Dilek Erkan
BACKGROUND AND OBJECTIVES To evaluate the outcomes of vitreoretinal surgery for the ocular complications of Behcets disease. PATIENTS AND METHODS This retrospective study included 20 eyes of 15 patients with Behçets disease (9 men, 6 women; mean age at surgery, 31.0 +/- 1.8 years; range, 21-44 years) who had undergone vitreoretinal surgery for Behcets disease at Ondokuz Mayis University, Faculty of Medicine, Department of Ophthalmology, Samsun, Turkey, between January 2000 and September 2003. Postoperative visual acuity outcome, course of uveitis, and complications were evaluated in all patients. RESULTS Indications for surgery were vitreous opacities in 10 eyes (50%), cystoid macular edema in 5 eyes (25%), epiretinal membrane in 3 eyes (15%), and vitreous hemorrhage in 2 eyes (10%). At the last postoperative follow-up, visual acuity had increased 2 Snellen lines or more in 10 (50%) of 20 eyes. Cystoid macular edema completely improved in 3 (60%) of 5 eyes after vitrectomy. Uveitis attacks significantly decreased during follow-up (P = .015). Immunosuppressive treatment was stopped in 11 (73%) of 15 patients. Retinal detachment and phthisis were not observed in any eye. CONCLUSION Vitreoretinal surgery may be useful in the treatment of posterior segment complications of Behcets disease.
Medical Principles and Practice | 2011
İnci Güngör; Levent Güngör; Yakup Özarslan; Nurşen Aritürk; Ümit Beden; Dilek Erkan; Musa Onar; İhsan Öge
Objective: To compare the incidence of glaucomatous optic disk appearance between patients with symptomatic atherosclerotic stroke and healthy individuals with normal intraocular pressures (IOP). Subjects and Methods: 46 patients with ischemic stroke with evident lacunar infarction or large vessel atherosclerosis, and 93 age- and sex-matched healthy individuals, all with normal IOP, were included. Patients and controls were examined for the presence of high cup-to-disk ratios (>0.5). Results: Seven patients (15.22%) in the ischemic cerebrovascular disease (CVD) group and 3 controls (3.23%) had glaucomatous optic disk appearance. All subjects with glaucomatous optic disk appearance in the control group and 3 patients in the study group had visual field defects in concordance with normal-tension glaucoma (NTG). The incidence of glaucomatous optic disk appearance was significantly higher in the group with symptomatic atherosclerotic CVD. Conclusion: Atherosclerotic CVD is a risk factor for having glaucomatous optic disk appearance. Symptomatic atherosclerosis involving the brain vasculature may also affect the eye and lead to NTG. Patients with ischemic strokes due to large artery atherosclerosis or small artery occlusion must be examined and followed for NTG.
Ocular Immunology and Inflammation | 2006
İnci Güngör; Nurşen Aritürk; Ümit Beden; Özge Darka
Purpose: To report a case with necrotizing scleritis due to varicella-zoster infection. Methods: The patient records were evaluated. The present literature was investigated using MEDLINE. A six-year-old boy with varicella infection was admitted to our clinic with redness, pain, and lid edema on the right eye. Slit lamp examination revealed lid edema, purulent secretion, conjunctival injection and chemosis, and inferotemporal scleral necrosis. Sclera was avascular and the conjunctiva was spontaneously detached from sclera in the necrotic region. Results: Systemic and topical acyclovir treatment was started and a rapid improvement achieved in signs and symptoms. Conclusions: Ophthalmic manifestations of varicella infection are potentially blinding especially in the absence of appropriate diagnosis and medical intervention. Distinctive skin eruptions are specifically helpful in the early diagnosis of the disease.
Ophthalmic Surgery Lasers & Imaging | 2005
İnci Güngör; Ümit Beden; Dilek Erkan
A rare side effect of betamethasone applied subconjunctivally is described. A 51-year-old man who had undergone penetrating keratoplasty in his left eye 2 months previously developed graft rejection and was treated by subconjunctival injection of betamethasone. Within 2 weeks, the patient complained of conjunctival hyperemia and irritation. Biomicroscopic examination revealed conjunctival and subconjunctival necrosis with white necrotic tissue at the subconjunctival corticosteroid injection site. Simple debridement and primary wound closure of the involved area resulted in complete healing. Ophthalmologists should be aware that subconjunctival injection of betamethasone may cause conjunctival necrosis.
Ophthalmic Surgery Lasers & Imaging | 2008
Baris Sonmez; Ümit Beden; Volkan Yeter; Dilek Erkan
A 25-year-old woman presented to the emergency room 2 hours after a jellyfish sting to the left eye. Centrally located linear epithelial defects were observed on slit-lamp evaluation. The epithelial defects improved but did not heal totally after meticulous patching with antibiotic ointment and cycloplegic drops. Small, subepithelial negative staining areas within the epithelial defects were observed on day 3. Confocal microscopy was performed and revealed thread-like hyperreflective structures, mainly located at the basal epithelial layer. Following debridement of the traumatized areas, the corneal epithelium healed completely in 24 hours, resulting in increased visual acuity and decreased foreign body sensation. Jellyfish stings to the eye may involve the intrusion of the nematocysts, thread-like venomous structures, into the cornea. Debridement of these foreign bodies can be helpful in the treatment of resistant cases.