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Featured researches published by Ahmet Taylan Yazici.
Journal of Refractive Surgery | 2010
Ahmet Taylan Yazici; Ercument Bozkurt; Cengiz Alagöz; Neşe Alagöz; Gökhan Pekel; Vedat Kaya; Ömer Yilmaz
PURPOSE To evaluate the agreement among three different optical methods in measuring anterior chamber depth (ACD), central corneal thickness (CCT), and pupil diameter. METHODS One hundred eyes of 50 healthy patients (25 men, 25 women) were enrolled in the study. Mean patient age was 25 years (range: 21 to 32 years). Exclusion criteria were history of any intraocular or corneal surgery, contact lens wear, corneal anomalies, and spherical refraction >5.00 diopters (D) or cylindrical refraction >2.00 D. All measurements were done by the same operator under mesopic light conditions and repeated using three different optical methods: Visante optical coherence tomography (OCT) (Carl Zeiss Meditec), Orbscan (Bausch & Lomb), and Pentacam (Oculus Optikgeräte GmbH). RESULTS Mean CCT as measured by Visante OCT, Orbscan, and Pentacam was 529+/-30.5 microm, 554+/-32.7 microm, and 552+/-29.3 microm, respectively. Mean ACD values were 2.94+/-0.34 mm, 2.84+/-0.33 mm, and 2.98+/-0.33 mm, respectively. Mean pupil diameter measurements were 4.87+/-1.09 mm, 4.0+/-0.67 mm, and 3.05+/-0.59 mm, respectively. The Visante OCT measured CCT thinner and Orbscan measured ACD shallower than the other two methods. All three methods measured pupil diameters significantly different. CONCLUSIONS This study found some statistically significant but clinically insignificant differences among the optical methods assessed. The differences are small and do not influence decisions for refractive surgery in clinical practice.
Current Eye Research | 2010
Osman Çekiç; Mehmet Çakır; Ahmet Taylan Yazici; Neşe Alagöz; Ercument Bozkurt; Ömer Yilmaz
Purpose: To compare the efficacy of intravitreal injection of triamcinolone, bevacizumab, and a combination of triamcinolone-bevacizumab for the management of macular edema due to branch retinal vein occlusion. Methods: Fifty-two eyes of 52 patients (29 male, 23 female) with branch retinal vein occlusion and macular edema were included. Patients received one of the following intravitreal treatments: 4 mg triamcinolone acetonide monotherapy (n = 17), 1.25 mg bevacizumab monotherapy (n = 14) or a combination of 2 mg triamcinolone acetonide and 1.25 mg bevacizumab (n = 21). Measurements of Snellen visual acuity and central macular thickness with optical coherence tomography were done at baseline, and at months one, three, and six. Results: At baseline, the three groups did not differ in age (P = 0.12), duration of macular edema (P = 0.24), visual acuity (P = 0.62), central macular thickness (P = 0.16), and intraocular pressure (P = 0.15). All study groups showed significant reduction of central macular thickness (P = 0.02, P = 0.02, and P = 0.001, respectively) and improvement in visual acuity (P = 0.02, P = 0.02 and P = 0.02, respectively) one month after injection. At six months, there was a significant reduction in central macular thickness (P = 0.02, P = 0.02, and P = 0.04, respectively) while only bevacizumab monotheraphy group demonstrated significant improvement in visual acuity (P = 0.01). Conclusion: Intravitreal injection of triamcinolone, bevacizumab or combination of triamcinolone-bevacizumab appears to have similar therapeutic effects on macular edema due to branch retinal vein occlusion at one month. Intravitreal injection of bevacizumab yielded better results of visual acuity than the others at six months.
Journal of Cataract and Refractive Surgery | 2012
Necip Kara; Ercument Bozkurt; Ökkeş Baz; Hasan Altinkaynak; Hüseyin Dündar; Kemal Yuksel; Ahmet Taylan Yazici; Ahmet Demirok; Sukru Candan
PURPOSE: To compare the biomechanical properties of the cornea and intraocular pressure (IOP) between patients with Marfan syndrome and age‐matched controls. SETTING: Departments of Ophthalmology and Genetics, Bakirkoy Maternity and Children Diseases Hospital, and Beyoglu Eye Education and Research Hospital, Istanbul, Turkey. DESIGN: Cross‐sectional study. METHODS: This study comprised patients with Marfan syndrome (study group) and healthy individuals (control group). The study group was subdivided into patients with ectopia lentis and patients without ectopia lentis. In the right eye of each patient, the corneal hysteresis (CH), corneal resistance factor (CRF), Goldman‐correlated IOP, and corneal‐compensated IOP were recorded. RESULTS: Overall, the mean CH, CRF, Goldman‐correlated IOP, and corneal‐compensated IOP were not significantly different between the study group and the control group. The mean CH was 9.9 mm Hg ± 1.2 (SD) in study eyes with ectopia lentis and 11.2 ± 1.5 mm Hg in study eyes without ectopia lentis (P=.016); the mean CRF was 8.2 ± 1.8 mm Hg and 11.3 ± 1.9 mm Hg, respectively (P<.001). The mean Goldman‐correlated IOP was 11.7 ± 2.7 mm Hg in study eyes with ectopia lentis and 16.2 ± 4.3 in study eyes without ectopia lentis (P=.003); the mean corneal‐compensated IOP was 13.5 ± 4.1 mm Hg and 15.6 ± 3.8 mm Hg, respectively (P=.07). CONCLUSION: The CH, CRF, and Goldman‐correlated IOP were significantly lower in the Marfan syndrome eyes with ectopia lentis than in the Marfan syndrome eyes without ectopia lentis. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.
American Journal of Ophthalmology | 2011
Ercument Bozkurt; Necip Kara; Ahmet Taylan Yazici; Kemal Yuksel; Ahmet Demirok; Ömer Yilmaz; Serif Demir
PURPOSE To evaluate the prophylactic efficacy of selective laser trabeculoplasty for preventing an increase in intraocular pressure (IOP) after intravitreal triamcinolone acetonide injection. DESIGN Prospective, comparative, interventional case series. METHODS We studied 31 eyes with a baseline IOP of 21 mm Hg or more of 31 patients for which intravitreal triamcinolone acetonide injection was planned for diabetic macular edema. The patients were divided into 2 groups, a study group and control group. The study group comprised 15 eyes of 15 patients that underwent selective laser trabeculoplasty a mean of 8.3 ± 4.1 days before intravitreal triamcinolone acetonide injection. The control group comprised 16 eyes of 16 patients who underwent only intravitreal triamcinolone acetonide injection. Main outcomes measures were mean IOP and number of patients requiring antiglaucomatous therapy. RESULTS Mean baseline IOP was 21.6 ± 0.9 mm Hg in the study group and 21.5 ± 0.8 mm Hg in the control group (P = .98). Mean IOP at 1 day after injection was 17.0 ± 2.0 mm Hg in the study group and 19.5 ± 4.3 mm Hg in the control group (P = .23). Mean IOP at 1 week after injection was 16.9 ± 1.7 mm Hg and 18.4 ± 4.0 mm Hg, respectively (P = .49); mean IOP at 1 month after injection was 16.4 ± 1.5 mm Hg and 20.8 ± 5.6 mm Hg, respectively (P = .003); mean IOP at 3 months after injection was 15.8 ± 2.5 mm Hg and 18.3 ± 5.5 mm Hg, respectively (P = .01); and mean IOP at 6 months after injection was 15.7 ± 1.4 mm Hg and 17.1 ± 1.5 mm Hg, respectively (P = .03). The number of patients requiring antiglaucomatous therapy during follow-up was 0 of 15 eyes in the study group and 8 of 16 eyes in the control group (P = .001). CONCLUSIONS The IOP elevation after intravitreal triamcinolone acetonide injection may be prevented by performing selective laser trabeculoplasty before intravitreal triamcinolone acetonide injection, especially in cases with a baseline IOP of 21 mm Hg or more.
Retina-the Journal of Retinal and Vitreous Diseases | 2011
Ahmet Taylan Yazici; Neşe Alagöz; Haci U Çelik; Ercument Bozkurt; Cengiz Alagöz; Mehmet Çakır; Osman Çekiç; Ömer Yilmaz
Purpose: The purpose of this study was to define the morphologic differences in idiopathic and secondary epiretinal membranes (ERMs) using a time domain optical coherence tomography. Methods: The medical records and optical coherence tomography images of 293 eyes of 236 consecutive patients diagnosed to have ERM were evaluated retrospectively. Demographic features, best-corrected visual acuities, central macular thickness, membrane attachment patterns, macular changes, and the presence of posterior retinal detachment at the time of diagnosis were compared between the groups (idiopathic group, n = 125 eyes; secondary group, n = 168 eyes). Results: The mean age was higher among idiopathic ERMs (67 ± 9 vs. 62 ± 10 years, P = 0.001). In the secondary group, best-corrected visual acuity was estimated to be worse (P < 0.001) and central macular thickness higher (P = 0.02) than the idiopathic group. In both groups, ERMs were mostly diagnosed at Grade 1 level. Diffuse attachment was more common in both of the groups. Among macular changes, only cystoid macular degeneration differed significantly between the groups (P = 0.0001). Conclusion: Idiopathic and secondary ERMs were estimated to differ significantly at the time of diagnosis in terms of age, visual acuities, macular thickness, presence of cystoid macular degeneration, and posterior vitreous detachment. These parameters may assist the retinal surgeon in the treatment process of ERM.
Clinical Ophthalmology | 2014
Zeynep Alkin; Irfan Perente; Abdullah Ozkaya; Dilek Alp; Alper Agca; Ebru Demet Aygit; Selcuk Korkmaz; Ahmet Taylan Yazici; Ahmet Demirok
Purpose To compare the efficacy of low-fluence photodynamic therapy (PDT) and PDT with half-dose verteporfin in chronic central serous chorioretinopathy (CSC). Patients and methods The medical records of 64 eyes from 60 patients with chronic CSC were retrospectively reviewed; 36 eyes received low-fluence PDT (25 J/cm2) and 28 eyes received half-dose verteporfin PDT (3 mg/m2). The primary outcome measure was the proportion of eyes with complete resolution of subretinal fluid. Secondary outcome measures were the changes in best corrected visual acuity (BCVA) and central foveal thickness, and the proportion of eyes that showed an increase of ≥5 letters in BCVA at the last visit. Results The mean follow-up period was 12.5±4.3 months and 13.1±4 months in the low-fluence group and half-dose group, respectively (P=0.568). Thirty-three eyes (91.6%) in the low-fluence group and 26 eyes (92.8%) in the half-dose verteporfin group showed complete resolution of subretinal fluid (P=0.703). BCVA increased by a mean of 7.4 letters and 4.8 letters in the low-fluence group and half-dose group, respectively (P=0.336). Seventeen eyes (52.8%) in the low-fluence group and 14 eyes (50%) in the half-dose group experienced a gain of ≥5 letters in BCVA (P=0.825). In the low-fluence and half-dose verteporfin group, the mean baseline central foveal thickness was 351±90 μm and 341±96 μm, and significantly decreased to 188±61 μm and 181±47 μm, respectively (P<0.01). Conclusion Both treatments resulted in complete subretinal fluid resolution in most of the eyes, with significantly better visual acuity outcomes compared to baseline at the last visit.
Journal of Ophthalmology | 2013
Ozen Ayranci Osmanbasoglu; Zeynep Alkin; Abdullah Ozkaya; Yavuz Ozpinar; Ahmet Taylan Yazici; Ahmet Demirok
Purpose. To analyse the diurnal variation of central choroidal thickness (CCT) in healthy emetropic patients during working hours. Methods. Fifty healthy young emmetrpic volunteers were included in this study. CCT was measured at 9 AM and 4 PM with spectral domain optical coherence tomography (Spectralis, Heidelberg Engineering) with enhanced depth imaging. Diurnal variation of CCT, the correlation between rigth and left eyes and the demographic factors affecting this variation were assessed. Findings. The mean CCT at 9 AM and 4 PM was 308.7 ± 64.5 μm and 308.7 ± 62 μm, respectively, with a mean diurnal amplitude of −0.03 ± 14.7 μm, ranging between −55 μm and 47 μm, the difference was statistically insignificant (P: 0.9). There were positive correlations between right and left eyes among CCT measurements at 9 AM, 4 PM and the mean amplitude of diurnal change (r: 0.65, P < 0.01; r: 0.60, P < 0.01; r: 0.45, P: 0.00, resp.). There was a statistically significant negative correlation between the magnitude of diurnal change and age (r: −0.27, P: 0.01). Conclusion. Although the mean CCT in the all group does not show significant variation during working hours, the pattern of diurnal variation may vary from person to person according to age, and there is a great harmony between the two eyes.
Journal of Cataract and Refractive Surgery | 2010
Ercument Bozkurt; Ahmet Taylan Yazici; Gökhan Pekel; Sinan Albayrak; Mehmet Çakır; Evre Pekel; Ömer Yilmaz
PURPOSE: To evaluate changes in central macular thickness using optical coherence tomography after uneventful cataract surgery combined with intracameral epinephrine use. SETTING: Beyoğlu Eye Training and Research Hospital, Istanbul, Turkey. METHODS: This prospective case series comprised eyes of consecutive patients who had uneventful phacoemulsification and in‐the‐bag intraocular lens (IOL) implantation between August 2005 and January 2006. The eyes were randomly assigned to 1 of 2 groups. In 1 group, 0.2 mL epinephrine (1:5000 solution) was injected just after the clear corneal incision was created. The other group (control) did not receive epinephrine. Optical coherence tomography was performed in all eyes preoperatively as well as postoperatively at 1 day, 1 week, and 1, 3, and 6 months. RESULTS: The epinephrine group comprised 73 eyes (73 patients) and the control group, 76 eyes (86 patients). In both groups, the increase in retinal thickness from preoperatively to 1, 3, and 6 months postoperatively was statistically significant (P<.05); the difference was not statistically significant at 1 day or 1 week in either group (P>.05). There were no statistically significant differences between the 2 groups in mean retinal thickness throughout the follow‐up (P>.05). Clinically significant macular edema occurred in 3 eyes in the epinephrine group and 3 eyes in the control group. CONCLUSION: Although epinephrine is a well‐known risk factor for central macular edema, intracameral injection of 0.2 mL epinephrine (1:5000) did not increase the risk for central macular edema in eyes with no risk factors that had uneventful phacoemulsification with IOL implantation. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.
Middle East African Journal of Ophthalmology | 2012
Ahmet Taylan Yazici; Ercument Bozkurt; Necip Kara; Yusuf Yildirim; Ahmet Demirok; Ömer Yilmaz
Objective: To evaluate the 2-year outcomes of phacoemulsification combined with primary posterior curvilinear capsulorhexis (PPCC) in adults. Materials and Methods: In this retrospective case series, 93 eyes of 91 patients with bilateral age-related cataract who underwent phacoemulsification combined with PPCC were evaluated. The study included cases due to postoperative residual posterior capsule opacification despite careful polishing. Data were evaluated on preoperative and postoperative best corrected visual acuity (CDVA) (Snellen acuity), slit-lamp biomicroscopy and intraocular pressure (IOP) measurement. Perioperative and postoperative complications were also recorded. Results: The mean follow-up was 24.9 ±13.5 months (range, 12-53 months). At the last visit, 87.1% of the eyes had CDVA ≥ 20/40 and 58% had ≥ 20/25. Posterior capsular opacification (PCO) occurred in 2 (2.2%) of patients. No serious complications such as retinal detachment and endophthalmitis were observed during follow-up. Conclusions: Cataract surgery combined with PPCC is a safe procedure with a low rate of complications over the long term. This procedure reduced the necessity of Nd:YAG laser capsulotomy in adults with postoperative residual posterior capsule opacification despite careful polishing.
Current Eye Research | 2014
Hasan Altinkaynak; Necip Kara; Nihat Sayin; Hasan Gunes; Şahin Avşar; Ahmet Taylan Yazici
Abstract Purpose: To evaluate the subfoveal choroidal thickness (SFCT) measured by enhanced depth imaging optical coherence tomography (EDI-OCT) in eyes of chronic heart failure (CHF) patients. Methods: Fifty-six patients with CHF and 56 age- and gender-matched healthy individuals were enrolled. The SFCT was measured by EDI-OCT. The ejection fraction of left ventricle (EFLV), age, intraocular pressure (IOP), axial length (AL), systolic and diastolic blood pressure, and ocular perfusion pressure (OPP) were also measured. Results: Mean SFCT was 181.2 ± 80.23 μm in the study group and 283.6 ± 52.4 μm in the control group (p = 0.000). There was a statistically significant correlation between the SFCT and each of EFLV and age. SFCT value was not statistically significantly associated with AL, IOP and OPP. Conclusıon: Our results suggest that SFCT is lower in eyes of CHF patients compared to age- and gender-matched healthy individuals.