Nevbahar Tamcelik
Istanbul University
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Featured researches published by Nevbahar Tamcelik.
British Journal of Ophthalmology | 2007
Mustafa Ünal; Mehmet Güven; Kazım Devranoğlu; Ahmet Ozaydin; Bahadir Batar; Nevbahar Tamcelik; Ebru Gorgun; Didar Ucar; Ahmet Sarici
Background: Genetic factors and oxidative damage have been shown to have a role in the development of primary open angle glaucoma (POAG). Aim: To determine the effects of genetic polymorphisms of glutathione S transferase (GST)M1 and GSTT1 on the risk of POAG in a Turkish population. Methods: Using a multiplex polymerase chain reaction (PCR), GSTM1 and GSTT1 gene polymorphisms were analysed in 144 patients with POAG and in 121 otherwise healthy controls of similar age. Results: The GSTM1 positive genotype and the GSTT1 null genotype had an increased risk of developing POAG (p<0.001, OR 2.93, 95% CI 1.66 to 5.20 and OR 4.25, 95% CI 2.30 to 7.80, respectively). The risk of glaucoma also increased significantly in subjects with a combination of GSTM1 positive and GSTT1 null genotypes (p<0.001, OR 3.46, 95% CI 1.64 to 7.38). Conclusion: The GSTM1 positive genotype and GSTT1 null genotype or the combination of both may be associated with the increased risk of development of POAG in the Turkish population.
British Journal of Ophthalmology | 2014
Ahmet Özkök; Esra Hatipoglu; Nevbahar Tamcelik; Burcu Balta; Ahmet Sadi Gundogdu; Mehmet Akif Ozdamar; Pinar Kadioglu
Purpose Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) excess in acromegaly have various effects on many organs. The ophthalmologic effects of GH and IGF-1 excess have not yet been investigated in detail. The aim of the current study is to compare the corneal biomechanical properties of patients with acromegaly and those of healthy subjects. Methods 45 patients with acromegaly (F/M=27/18) and 42 age-matched and gender-matched healthy individuals (F/M=24/18) were enrolled in this cross-sectional study. Central corneal thickness (CCT), corneal resistance factor (CRF), corneal hysteresis (CH), corneal compensated intraocular pressure (IOPcc) and Goldmann correlated IOPG were measured in patients with acromegaly and in healthy individuals using the Ocular Response Analyser (ORA). GH and IGF1 values were also determined in the study group. Results The mean CH and CRF values were higher in acromegalic patients (12.1±2.2 and 12.3±2.4, respectively) than in healthy subjects (11.0±1.6 and 10.8±1.5, respectively; for CH, p=0.014; for CRF, p=0.001). Mean IOPG measurement was higher in the acromegaly group than in the control group (p=0.017). There was no statistically significant difference in measured CCT (p=0.117) and IOPcc (p=0.594) values between acromegalic patients and healthy subjects. Conclusions These findings indicate that acromegaly has target organ effects on the eye. Consequently, it can change corneal biomechanical properties such as corneal hysteresis and the CRF. Corneal biomechanical properties are known to affect the accuracy of IOP measurements. These findings should be taken into account when measuring IOP values in acromegaly patients, as IOP readings may be overestimated.
Ophthalmologica | 1999
Mustafa Guzey; Osman Sevki Arslan; Nevbahar Tamcelik; Ahmet Satici
In order to investigate the effects of laser trabeculoplasty (LT) on diurnal intraocular pressure (IOP) variations in 36 eyes of 30 cases with primary open-angle glaucoma (POAG) in which medical treatment was terminated, the IOP curves, recorded 24 h before as well as 24 h and 12 weeks after LT were compared. Twelve weeks after LT, significant IOP decreases were observed: 36.42% in the mean IOP, 29.77% in the mean peak IOP and 50.04% in the mean pressure range. LT might therefore have beneficial effects on the diurnal IOP variations in cases with POAG.
Ophthalmic Surgery and Lasers | 2001
Akif Ozdamar; Cengiz Aras; Can Ustundag; Nevbahar Tamcelik; Sehirbay Ozkan
The technique described in this paper shows how to use a long scleral tunnel for the implantation of anterior tube parts of glaucoma drainage devices. It involves the creation of a scleral tunnel beginning 10 mm behind the limbus and extending to the anterior chamber. Anterior tube parts of Krupin eye valve with disk is inserted through the scleral tunnel to the anterior chamber. The disk part is secured to the episclera as used in the standard technique. We have used this technique in 6 eyes of 6 consecutive patients with refractory glaucoma. The placement of anterior tubes as part of glaucoma seton devices was done in all patients. While mean intraocular pressure (IOP) was 39.3 +/- 4.9 mm Hg (ranged from 29 to 56 mm Hg) preoperatively, it was 16.6 +/- 5.3 mm Hg (ranging from 11 to 25 mm Hg) at the end of follow up. Mean follow-up time was 7.16 +/- 1.16 months (ranging from 6 to 9 months). After surgery, conjunctival erosion or displacement of the anterior tube and dellen formation were not found in any eyes. The use of a long scleral tunnel for the implantation of anterior tube parts of glaucoma seton devices offers some advantages over standard implantation techniques.
Journal of Glaucoma | 2013
Ahmet Özkök; Nevbahar Tamcelik; Akif Ozdamar; Ahmet Sarici; Erdogan Cicik
Purpose:The aims of this study were to assess the biomechanical properties of corneas with pseudoexfoliative glaucoma (PEXG) and to compare them with those of patients with primary open-angle glaucoma (POAG). Methods:This prospective, comparative case series consisted of 73 eyes of 73 patients, 35 eyes with PEXG (PEXG group) and 38 eyes with POAG (POAG group). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPCC), and Goldmann-correlated intraocular pressure (IOPG) were determined by using ocular response analyzer (ORA). IOP using Goldmann applanation tonometer (GAT) and ultrasonic central corneal thickness (CCT) were also measured for each eye. Exclusion criteria included refractive error/astigmatism of >3.00 D, history of intraocular surgery, corneal disease, angle-closure glaucoma, and secondary glaucoma other than PEXG. In cases where both eyes were eligible, the right eye was preferred for analysis. The main outcome measures were CH, CRF, IOPCC, IOPG, and GAT. The results were statistically analyzed by using t test, general linear model, and the Pearson correlation test. Results:The mean CH was found to be significantly lower in patients with PEXG (8.8±1.4 mm Hg) than those with primary open-angle glaucoma (9.9±1.2 mm Hg; P=0.0007). The mean CRF was found to be significantly lower in patients with PEXG (9.5±1.8 mm Hg) than those with POAG (11.1±1.3 mm Hg; P<0.0001). IOPCC was not significantly different between the groups (PEXG, 16.7 ±2.5 mm Hg; POAG, 16.9±2.4 mm Hg; P=0.72). IOPG was significantly lower in PEXG group (14.7±2.7 mm Hg) compared with the POAG group (16.5±2.5 mm Hg; P=0.004). GAT was significantly lower in the PEXG group (14.6±2.7 mm Hg) compared with the POAG group (16.4±2.8 mm Hg; P=0.007). There was no significant difference between the groups regarding mean CCT (PEXG, 546.1±34.9 &mgr;; POAG, 549.1±25 &mgr;; P=0.66) and mean age (PEXG, 70.3±8.2; POAG, 67.6±8.8; P=0.17). The difference between the IOPCC and the GAT was 2.1 and 0.5 mm Hg in both PEXG and POAG groups, respectively. Conclusions:Patients with PEXG had lower CH and CRF values than those with POAG. These findings require further investigation to assess the role of differing corneal biomechanical properties between the 2 groups and its association with poor prognosis among patients with PEXG.
Cornea | 2002
Nevbahar Tamcelik; Akif Ozdamar; Melda Kizilkaya; Kazım Devranoğlu; Can Ustundag; Cuyan Demirkesen
Purpose. The purpose was to report a case of fungal keratitis that occurred following viscocanalostomy. Methods. A 63-year-old man who underwent viscocanalostomy in his left eye presented with pain, redness, watering, and a decrease in visual acuity. Slit lamp examination showed teardrop-like stromal infiltration of the superior cornea. Corneal and conjunctival scrapings were obtained and a corneal biopsy was performed. Results. Microscopic examination of smears demonstrated no bacteria and fungi. Corneal biopsy revealed dichotomously branching, septate hyphae suggestive of Aspergillus species. Culture identified no microorganism. The patient responded to amphotericin B treatment and the corneal infiltration resolved, leaving a plaquelike corneal scar. Conclusion. Fungal keratitis may occur after viscocanalostomy, but prompt diagnosis and treatment can preserve the eye.
Ophthalmic Research | 2015
Nevbahar Tamcelik; Eray Atalay; Erdogan Cicik; Ahmet Özkök
Purpose: To evaluate the agreement between the reading values of the Goldmann applanation tonometer (GAT), Icare Pro rebound tonometer (IRT) and noncontact tonometer (NCT) in glaucoma patients. Methods: This cross-sectional study comprised 292 eyes of 292 patients selected from a glaucoma outpatient clinic. The intraocular pressure (IOP) was measured sequentially, at a 10-min interval each, in the following order: NCT, IRT and GAT. The central corneal thickness (CCT) was measured using Pentacam HR before the IOP measurements. Results: The mean IOPs measured by the GAT, NCT and IRT were 20.17 ± 6.73 mm Hg (range: 4-48), 19.77 ± 6.88 mm Hg (range: 3-46) and 19.30 ± 5.15 mm Hg (range: 7.30-44.5), respectively. The correlation coefficients of the GAT and IRT, NCT and IRT, and GAT and NCT measurements were r2 = 0.673, r2 = 0.663 and r2 = 0.938 (all p < 0.001), respectively. The IRT tends to overestimate in the low GAT-measured IOPs, whereas it underestimates in high GAT-measured IOPs. The measurements of all 3 devices were also correlated with the CCT at a statistically significant level (GAT: r2 = 0.063, NCT: r2 = 0.063, IRT: r2 = 0.058). Conclusion: The agreement between the IRT and GAT measurements is higher in the IOP range of 9-22 mm Hg, whereas significant discrepancies occur as the IOP deviates from normal values. The variability of the IRT and GAT measurements over a wide range of CCT is minimal.
Indian Journal of Ophthalmology | 2014
Nevbahar Tamcelik; Eray Atalay; Selim Bölükbaşı; Olgu Çapar; Ahmet Özkök
Context: Congenital glaucoma is a potentially blinding ocular disease of the childhood. Identification of the possible associated risk factors and may be helpful for prevention or early detection of this public health problem. Aims: To demonstrate the demographic features of congenital glaucoma subjects. Setting and Design: The charts of congenital glaucoma patients referred to Tamcelik Glaucoma Center were retrospectively reviewed through the dates of 2000 and 2013. Materials and Methods: Analyzed data included diagnosis, age at first presentation, symptoms at first presentation, laterality of the disease, sex, presence of consanguinity, family history of congenital glaucoma, maturity of the fetus at delivery, and maternal age at conception. Statistical Analysis Used: Statistical Package for Social Sciences (SPSS) version 19.0 by IBM (SPSS Inc, Chicago, Illinois, USA) was used to compare the mean of continuous variables with Students t-test and analysis of variance (ANOVA) and χ2 test was used to test differences in proportions of categorical variables. Results: The data of 600 eyes of 311 patients were analyzed. The distribution of primary and secondary congenital glaucoma among the patients were 63.3% (n = 197) and 36.7% (n = 114), respectively. Of the 311 patients, 57.2% (n = 178) were male and 42.8% (n = 133) were female. The overall frequency of bilateral disease was 92.3% (n = 287). Overall rate of consanguinity and positive family history was 45.3% (n = 141) and 21.2% (n = 66), respectively. Conclusions: Bilateral disease in this study was more common than previously reported studies. Positive family history was more frequent in primary congenital glaucoma although not statistically significant.
Japanese Journal of Ophthalmology | 2004
Nevbahar Tamcelik; Abdullah Ozkiris
PurposeTo compare the success and complication rates of viscogoniotomy and goniotomy in Turkish patients.MethodsIn a retrospective review, the medical records of patients with primary congenital glaucoma were divided into two groups. Group 1 consisted of 21 patients (38 eyes) who had undergone classical goniotomy, and group 2 consisted of 25 patients (44 eyes) who had undergone viscogoniotomy. The success rates and intra- and postoperative complications were compared between the two groups.ResultsMean preoperative introcular pressure (IOP) was 28.9 ± 3.6 mmHg in group 1 and 29.3 ± 2.8 mmHg in group 2. At the last postoperative visit, it was 17.3 ± 3.1 mmHg and 16.2 ± 2.1 mmHg, respectively (P < 0.001). The success rates at the last visit of group 1 and group 2 were 68.4% and 88.6%, respectively (P < 0.05). The most common early postoperative complication was hyphema in group 1 and transient IOP elevation in group 2.ConclusionViscogoniotomy may increase the success rate and decrease the complications rate by preventing hyphema and flat anterior chamber.
International Journal of Ophthalmology | 2015
Ahmet Özkök; Julide Canan Umurhan Akkan; Nevbahar Tamcelik; Mehmet Erdogan; Didar Ucar Comlekoglu; Rengin Yildirim
AIM To compare retinal nerve fiber layer (RNFL) and macular thickness measurements obtained with the Stratus optical coherence tomography (OCT) and OPKO/OTI OCT devices. METHODS Included in the study were 59 eyes of 30 participants. All measurements for each eye were done on the same day with both devices. Students paired t-tests were used to compare the central macular thickness and RNFL measurements of the Stratus OCT and OPKO/OTI OCT. Pearson correlation was used to assess the relationship between the devices. Coefficient of variation (COV) was calculated to assess intersession repeatability. RESULTS Using both the Stratus OCT and OPKO/OTI OCT, respectively, the measured mean average RNFL thicknesses were 98.9±11.1 µm and 115.1±9.6 µm (P=0.001), and the measured mean central retinal thicknesses (CRT) were 196.2±18.8 µm and 204.5±21.1 µm (P<0.001). Measured by the two devices, the RNFL thickness values were correlated in all quadrants, as were the retinal thickness values except the inferior outer sector. COV for average RNFL and CRT thickness were 2.9% and 4.6% for Stratus OCT, and 2.1% and 4.2% for OPKO/OTI OCT, respectively. CONCLUSION We found good reproducibility of RNFL and retina thickness measurements for both Stratus OCT and OPKO/OTI OCT devices. However, even though the two OCT systems provided statistically correlated results, the values for both RNFL and macular thickness were statistically different. RNFL and macular thickness measurements with the OPKO/OTI OCT were higher than that of the Stratus OCT; therefore, the two OCT systems cannot be used interchangeably for the measurements of RNFL and macular thickness.