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Browsing by Author "Akkoyun, Imren"

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    Analysis of Choroidal Thickness in AP-ROP, Threshold Disease and ROP Without Laser Photocoagulation
    (2016) Gokgoz-Ozisik, G.; Akkoyun, Imren; Oto, S.; Bayar, S. A.; Tarcan, A.; Kayhan, Z.; Yilmaz, G.; https://orcid.org/0000-0001-9037-7394; https://orcid.org/0000-0002-2860-7424; https://orcid.org/0000-0003-0171-4200; https://orcid.org/0000-0001-5109-755X; https://orcid.org/0000-0003-0579-1115; 26142227; ABG-6096-2021; AAK-7713-2021; AAJ-4668-2021; AAJ-2406-2021; AAJ-4623-2021
    Background. Enhanced depth imaging (EDI) and spectral domain optical coherence tomography (SD-OCT) provide high-definition cross-sectional images of the choroid. Information on alterations in choroidal thickness (CT) after laser photocoagulation (LC) in aggressive posterior retinopathy of prematurity (APROP) and threshold disease (TD) is rare. Patients and methods. A total of 75 eyes were retrospectively analyzed in 4 groups. Groups 1 and 2 included patients with APROP and TD, respectively, who underwent LC. Group 3 included ROP children who did not undergo LC and group 4 included full-term children. Infants aged >= 4 < 7, who had examination of subfoveal (SF) CT with SD-EDI-OCT, visual acuity (VA), spherical equivalent (SE), anterior segment and fundus examination, axial lenght (AXL) were included. The results of SFCT, VA and SE at the age of >= 4 < 7 years, AXL, gestational age (GA), birth weight (BW) and age at examination were compared between the groups. Potential risk factors (GA, BW, SE, AXL and SFCT) influencing visual acuity were evaluated by using multivariate linear regression analysis. Results. The results of SFCT and AXL were not significantly different between groups 2 and 3 or between groups 3 and 4. There was a significant difference between the other groups for SFCT and AXL and VA was significantly different between all groups. The SE was not significantly different between groups 3 and 4 but there was a significant difference for SE, BW and GA between the groups. Age at examination was not significantly different between the groups. Multivariate linear regression analysis revealed SFCT for groups 1 and 2, GA for group 3 and GA, SFCT and AXL for group 4 as independent risk factors influencing visual acuity. Conclusion. The regression model used for groups 1-4 explains the variation of the dependent risk factor LogMar VA for groups 1-4 with 31.2 %, 43.5 %, 9.6 % and 69.4 %, respectively. These values expressed in percentage demonstrate that even more predictors may influence the dependent factor LogMar VA than evaluated in the study.
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    Antiproliferative and anti-apoptotic effect of astaxanthin in an oxygen-induced retinopathy mouse model
    (2019) Kucukoduk, Ali; Helvacıoglu, Fatma; Haberal, Nihan; Dagdeviren, Atilla; Bacanli, Didem; Yilmaz, Gursel; Akkoyun, Imren; 0000-0001-8990-8282; 30851776; P-2877-2014
    Objective: To evaluate the impact of intravitreal (IV) and intraperitoneal (IP) astaxanthin (AST) injections on neovascular development (ND), retinal morphology, and apoptotic activity in a C57BL/6J mouse model with hyperoxia-induced retinopathy (HIR). Design: C57BL/6J mouse model. Methods: Two negative control groups (n = 6 each; one of which received IV sterile dimethyl sulfoxide [DMSO]) of C57BL/6J-type mice were exposed to room air. The HIR groups included 36 C57BL/6J-type mice exposed to 75% +/- 2% oxygen from postnatal day (PD) 7 to PD 12. On PD 12, these mice were randomized into 6 groups (n = 6 each): 2 HIR control groups (one of which received IV-DMSO), 2 IV-AST groups (10 and 100 mu g/mL), and 2 IP-AST groups (0.5 and 5 mg/kg). We measured ND by counting neovascular tufts in cross sections and examined histological, ultrastructural changes via light and electron microscopy. Apoptosis was detected using terminal deoxynucleotidyl transferase-mediated nick end-labeling. Results: No ND was detected in the negative control groups. ND levels were not significantly different between high- and low-dose AST for either means of administration. However, ND levels were significantly lower in the AST groups, regardless of delivery, compared to the control groups. The means of delivery (IP versus IV) also yielded significant differences in ND. The incidence of mitochondrial dysmorphology and apoptosis were lower in groups receiving AST. Conclusions: AST seems to suppress ND and has anti-apoptotic activity in the HIR mouse model.
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    Antiproliferative and Mitochondrial Protective Effects of Apigenin in an Oxygen-Induced Retinopathy In Vivo Mouse Model
    (2021) Sezenoz, Almila Sarigul; Akkoyun, Imren; Helvacioglu, Fatma; Haberal, Nihan; Dagdeviren, Attila; Bacanli, Didem; Yilmaz, Gursel; Oto, Sibel; 0000-0002-2860-7424; 34665015; AAK-7713-2021
    Purpose: To investigate the effects of a common dietary flavonoid apigenin on retinal endothelial cell proliferation, retinal morphological structure, and apoptotic cell death in an oxygen-induced retinopathy (OIR) mouse model to evaluate the possibility of the use of apigenin in the treatment of ocular neovascular diseases (ONDs). Methods: Ninety-six newborn C57BL/6J mice were included. Eight groups were randomized, each including 12 mice. Two negative control groups were kept in room air: the first without any injection and the second received intravitreal (IV) dimethyl sulfoxide (DMSO), which is the solvent we used. The OIR groups were exposed to 75% +/- 2% oxygen from postnatal days (PD) 7 to 12. On PD 12, the mice were randomly assigned to 6 groups: 2 OIR control groups (1 received no injection, 1 received IV-DMSO), 2 IV-apigenin groups (10 and 20 mu g/mL), and 2 intraperitoneal (IP)-apigenin groups (10 and 20 mg/kg). We quantified retinal endothelial cell proliferation by counting neovascular tufts in cross-sections and examined histological and ultrastructural changes through light and electron microscopy. We evaluated apoptosis by terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL). Results: We detected a significant increase in endothelial cell proliferation in the OIR groups. Groups receiving apigenin, both IP and IV, had significant decreases in endothelial cells, atypical mitochondrion count, and apoptotic cells compared with the groups receiving no injections. None of the apigenin-injected groups revealed cystic degeneration or cell loss. Conclusions: Apigenin suppresses neovascularization, has antiapoptotic and antioxidative effects in an OIR mouse model, and can be considered a promising agent for treating OND. Clinical trial (Project number: DA15/19).
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    Bilateral Asymmetric Rhegmatogenous Retinal Detachment in a Patient with Stickler Syndrome
    (2018) Yilmaz, Gursel; Ozturk, Caner; Sezenoz, Almila Sarigul; Akkoyun, Imren; 0000-0002-2589-7294; 0000-0002-2860-7424; 29755825; AAK-6987-2021; AAK-7713-2021
    Here we present the long-term anatomical and visual outcomes of bilateral asymmetric rhegmatogenous retinal detachment repair in a patient with Stickler syndrome. A 17-year-old girl presented with decreased visual acuity in both eyes for more than one year. Her best-corrected visual acuity (BCVA) was 0.1 in the right eye and 0.05 in the left eye. Slit-lamp anterior segment examination revealed subcapsular cataract in both eyes. Fundus examination showed bilateral rhegmatogenous retinal detachment, chronic retinal detachment accompanied by multiple retinal holes, tears and membranous fibrillary vitreous in the peripheral retina. Grade C2 proliferative vitreoretinopathy was observed in the left eye. Scleral buckling surgery was performed initially for both eyes. After the primary surgical procedure, retinal reattachment was achieved in the right eye and the left eye underwent phacoemulsification, intraocular lens implantation, pars plana vitrectomy (PPV), and silicone oil injection. After these surgical procedures retinal reattachment was achieved in the left eye. Silicone oil removal was performed six months after PPV surgery. After surgical treatment, BCVA was 0.6 in the right eye at the end of the 3.5-year follow-up period. After silicone oil removal, BCVA reached 0.2 in the left eye after 36 months of follow-up and retinal reattachment was achieved in both eyes. Scleral buckling surgery and PPV are effective and confidential methods for the treatment of chronic retinal detachment cases in Stickler syndrome.
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    Choroidal Thickness After Dexamethasone Implant or Aflibercept in Patients with Diabetic Macular Edema Persistent to Ranibizumab
    (2020) Aksoy, Mustafa; Yilmaz, Gursel; Vardarli, Irfan; Akkoyun, Imren; 0000-0002-2589-7294; 0000-0003-1513-7686; 0000-0002-2860-7424; 32460600; AAK-6987-2021; AAK-7713-2021
    Purpose: This study aims to compare subfoveal choroidal thicknesses (SFCTs) after intravitreal dexamethasone (IVD) or intravitreal aflibercept (IVA) treatment in patients with persistent diabetic macular edema (DME) unresponsive to intravitreal ranibizumab (IVR). Methods: The study consisted of patients with DME unresponsive to IVR treatment in which 37 were administered 1 dose IVD (group A) and 34 patients who were administered 3 doses of IVA (group B), as well as 35 healthy individuals (group C). Detailed ophthalmological examination and optical coherence tomography parameters of group A and group B, including central retinal thickness and SFCT, were retrospectively evaluated before and after treatment. Results from preinjection, and 1, 2, and 3 months after injection were analyzed. Results of group A and group B were compared within themselves and also compared with group C. Results: SFCT measurements were compared within group A and group B (1 = preinjection; 2 = 1 month postinjection; 3 = 2 months postinjection; 4 = 3 months postinjection). There was significant thinning in SFCT between 1-2, 1-3, 1-4, 2-3, 2-4, and 3-4 time intervals within both group A and group B (both P < 0.001). Comparison of SFCT measurements showed preinjection, 1-, and 2-month values of group A were significantly thicker than those of group C (P < 0.001), whereas there was no significant difference between 3-month values (P = 0.09). Preinjection, 1-, and 2-month values of group B were significantly thicker than those of group C (P < 0.001), whereas there was no significant difference between 3-month values (P = 0.06). Conclusions: Three month follow-up showed thinning in SFCT measurements in patients with persistent DME unresponsive to IVR who were applied IVD or IVA treatment.
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    Choroidal Thickness in Ocular Sarcoidosis during Quiescent Phase Using Enhanced Depth Imaging Optical Coherence Tomography
    (2014) Gungor, Sirel Gur; Akkoyun, Imren; Reyhan, Nihan Haberal; Yesilirmak, Nilufer; Yilmaz, Gursel; https://orcid.org/0000-0001-6178-8362; https://orcid.org/0000-0002-2860-7424; https://orcid.org/0000-0001-9852-9911; https://orcid.org/0000-0002-8632-2873; https://orcid.org/0000-0002-2589-7294; 24912003; AAD-5967-2021; AAK-7713-2021; AAK-4587-2021; AAD-7299-2020; AAK-6987-2021
    Purpose: To evaluate the choroidal thickness in patients with ocular sarcoidosis during quiescent phase using enhanced depth imaging optical coherence tomography (EDI-OCT) and comparing it with normal subjects. Method: Eighteen eyes of 9 patients with ocular sarcoidosis (8 women, 1 man, mean age: 59.12 +/- 18.49 years) were enrolled in this study. Their subfoveal choroidal thickness was measured using EDI-OCT in the quiescent phase of uveitis, and compared with the age-, sex-, and spherical equivalent-matched normal subjects (6 women, 3 men, mean age: 59.6 +/- 14.22 years). Results: The mean subfoveal choroidal thickness was 281.76 +/- 88.1 mm in patients with sarcoidosis and 342.32 +/- 71.02 mm in controls. Significant differences were found at points between nasal 1500 mm and temporal 1000 mm to the fovea between patients and control group (p = 0.002, at fovea). Conclusions: Patients with ocular sarcoidosis had thinner choroids in the quiescent phases when compared to normal subjects.
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    Choroidal Vascularity Index Changes in Different Treatments for Vitreomacular Traction
    (2023) Ercan, Zeynep Eylul; Gokgoz, Gulsah; Akkoyun, Imren; Yilmaz, Gursel; 0000-0002-2860-7424; 37572736; AAK-7713-2021
    Introduction: The aim of this study was to examine if choroidal vascularity index (CVI) is different in eyes with unilateral vitreomacular traction (VMT) from their healthy fellow eyes; and whether different treatments affect the CVI. Methods: The baseline and 8-week post treatment CVIs of 56 unilateral VMT patients that underwent spontaneous resolution (n = 30), vitreoretinal surgery (n = 16) or pneumatic vitreolysis (n = 10) were compared with fellow eyes using paired samples t-test. Partial correlation analyses correcting age and gender was used for calculations between treatment groups. P values < 0.05 were considered statistically significant. Results: The mean baseline CVI for VMT and control eyes had no statistically significant difference (p = 0.81, r= -0.38). The post traction release follow-up CVI of VMT eyes and contralateral eyes had no significant difference (p = 0.12, r = 0.49). In spontaneous resolution group, vitreoretinal surgery group and pneumatic vitreolysis group the baseline and follow up CVIs of VMT eyes were statistically similar (p = 0.72, p = 0.32 and p = 0.79 respectively).Spontaneous detachment patients' CVIs showed a 0.57 +/- 5.81% increase, vitreoretinal surgery group had a reduction of 1.098 +/- 4.76%, and the pneumatic vitreolysis patients showed a CVI reduction of 0.307 +/- 4.24%. However, none of these changes was found to be statistically significant when compared between the groups (p = 0.21, r = 0.02). Discussion: Previous studies have argued that vitreomacular traction might have a role on the choroidal changes seen in the vitreoretinal interface disorders. This study has shown that VMT alone does not cause any significant changes in choroidal vascular index pre or post traction release.
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    Clinical Spectrum of Ocular and Visual Dysfunction in Children with Periventricular Leukomalacia: A Need for an Interdisciplinary Approach
    (2021) Ozturker, Zeynep Kayaarasi; Bayar, Sezin Akca; Oto, Sibel; Aksoy, Sibel; Akkoyun, Imren; Sezer, Taner; 0000-0001-5109-755X; 0000-0003-0171-4200; 0000-0003-1395-6207; 0000-0002-2860-7424; AAJ-2406-2021; AAJ-4668-2021; AAK-7713-2021
    The study aimed to evaluate the ocular motility and visual and optic disc abnormalities in children diagnosed with periventricular leukomalacia (PVL). A retrospective analysis was performed on 51 consecutive children who had ophthalmic symptoms and were diagnosed with PVL by using magnetic resonance imaging. The patients were assessed for visual function, strabismus, cycloplegic refraction, fundus examination, and if appropriate, spectral-domain optical coherence tomography and visual field testing were applied. The primary outcome measures were the prevalence and visual and ocular motility dysfunctions. Mean age was 5.72 +/- 2.6 years (range = 1-12), median birth weight was 2,740 g (range =1,240-3,460), and median gestational age was 34 weeks (range = 28-38). In total, 21 patients (39.6%) had neurological deficit, 11 (21.5%) had intellectual disability, and 19 (37.2%) had no neurological symptom. In the spherical equivalent refractive error and cylinder power analysis, 10 patients had >= 3.0 D myopia, 15 had >= 3.0 D hyperopia, and eight had >= 2.50 D astigmatism. Thirteen (25.4%) children had a best-corrected visual acuity between 20/40 and 20/20 for Snellen card, while 9 (17.6%) had strabismic amblyopia and 6 (11.7%) had anisometropic amblyopia. Manifest strabismus was present in 35 patients (68.6%); of whom 12 had esotropia (23.5%), 16 had exotropia (31.3%) and 6 had vertical deviation (11.7%). Manifest or latent nystagmus was detected in 14 patients (27.4%). In 28 patients (54.9%), there was optic nerve abnormality. Two patients had hypoplastic disc, 14 had optic disc pallor, 7 had large cupping, and 5 had total optic atrophy. Six subjects underwent reliable visual field (VF) examinations, and all six had abnormal VFs, with inferior fields being most affected. Ocular motility disorders, optic nerve abnormalities, VF defects, and low visual acuity are common findings in this cohort of PVL patients and maybe the only presenting signs of the disease. The recognition of the visual disabilities and implementation of early rehabilitation may have a significant benefit in these children.
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    Comparison of intravitreal bevacizumab and triamcinolone acetonide theraphies for diffuse diabetic macular edema
    (2015) Aksoy, Sibel; Yilmaz, Gursel; Akkoyun, Imren; Yazici, Ayse Canan; 26086006
    AIM: To compare therapeutic effects of intravitreal triamcinolone acetonide (IVTA) versus intravitreal bevacizumab (IVB) injections for bilateral diffuse diabetic macular edema (DDME). METHODS: Forty eyes of 20 patients with bilateral DDME participated in this study. For each patient, 4 mg/0.1 mL IVTA was injected to one eye and 2.5 mg/0.1 mL IVB was injected to the other eye. The effects of injection for diabetic macular edema (DME) were evaluated using best -corrected visual acuity (BCVA), central macular thickness (CMT) by optical coherence tomography (OCT) and intraocular pressure (IOP) by applanation tonometer. Patients underwent eye examinations, including BCVA, CMT, and IOP at pre-injection, 1, 4, 8, 12 and 24wk after injection. During the follow -up, second injections were performed to eyes which have CMT greater than 400 pm at 12wk for salvage therapy. RESULTS: BCVA (logarithm of the minimum angle of resolution) at pre -injection, 1, 4, 8, 12 and 24wk after injection was 0.71 +/- 0.19, 0.62 +/- 0.23, 0.63 +/- 0.12, 0.63 +/- 0.13, 0.63 +/- 0.14 and 0.61 +/- 0.24 in the IVTA group and 0.68 +/- 0.25, 0.61 +/- 0.22, 0.60 +/- 0.24, 0.62 +/- 0.25, 0.65 +/- 0.26 and 0.59 +/- 0.25 in the IVB group, respectively. CMT (mu m) at pre-injection, 1, 4, 8, 12 and 24wk after injection was 544 +/- 125, 383 +/- 96, 335 +/- 87, 323 +/- 87, 333 +/- 92, 335 +/- 61 in the IVTA group and 514 +/- 100, 431 +/- 86, 428 +/- 107, 442 +/- 106, 478 +/- 112, 430 +/- 88 in the IVB group respectively. Reduction ratios of mean CMT were 29% at 1wk, 38% at 4wk, 40% at 8wk, 38% at 12wk, and 38% at 24wk in the IVTA group. Second IVTA injections were performed to the 6 eyes (30%) at 12wk. Reduction ratios of mean CMT were 16% at 1wk, 17% at 4wk, 14% at 8wk, 7% at 12wk, and 16% at 24wk in the IVB group. Second IVB injections were performed to the 15 eyes (75%) at 12wk. CONCLUSION: This study showed earlier and more frequent macular edema recurrences in the eyes treated with bevacizumab compared with the ones treated with triamcinolone acetonide. Triamcinolone acetonide was found to provide more efficient and long-standing effect in terms of reducing CMT compared with the bevacizumab.
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    The Correlation Of Atrophy, Traction And Neovascularization In Myopic Choroidal Neovascularization According To A Novel Myopic Maculopathy Classification System (Atrophy (A), Traction (T), Neovascularization (N): ATN)
    (2022) Kurt, Rengin Aslihan; Sezenoz, Almila Sarigul; Akkoyun, Imren; https://orcid.org/0000-0002-2860-7424; 35876940; AAK-7713-2021
    Purpose To grade myopic choroidal neovascularization (CNV) patients according to the new myopic maculopathy classification (A: atrophy, T: traction, N: neovascularization-ATN) and analyze the correlation in between atrophy, traction and neovascularization. Methods Fifty-one eyes of 41 patients with the diagnosis of pathologic myopia and myopic CNV were included in this clinical practice study. Patients were graded according to the recently described ATN classification. Color fundus photographs were used to grade the atrophy and spectral domain optical coherence tomography scans were used to grade traction and neovascularization. Active myopic CNVs were treated with intravitreal anti-vascular endothelial growth factor (VEGF) injections. Chi-square test was used to test the categorical variants and univariate logistic regression analysis was used to predict the independent risk factors of myopic CNV scar formation. Results Active myopic CNV was observed most frequently in the group with patchy chorioretinal atrophy. Grade of the atrophy and female gender were significantly associated with myopic CNV scar in the univariate logistic regression tests. Multivariate logistic regression showed that atrophy grading is the independent predictor of myopic CNV scar. Conclusion ATN classification is a practical and comprehensive system to grade myopic CNV. Atrophy is an independent predictor for myopic CNV scar and patchy chorioretinal atrophy requires a more careful examination and close follow-up for the risk of CNV development.
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    A diagnostic dilemma in a patient with delayed onset endophthalmitis
    (2019) Ercan, Zeynep Eylul; Akkoyun, Imren; Gungor, Sirel Gur; Yilmaz, Gursel; 0000-0001-6178-8362; 0000-0002-9915-3781; 30930672; AAD-5967-2021; AAQ-3136-2020
    We report a case of nonpainful uveitis nine months after an uncomplicated phacoemulsification cataract surgery. Chronic postoperative endophthalmitis was suspected. Diagnostic vitrectomy and partial capsular bag removal was performed, but the specimens cultured in microbiology laboratory showed no pathogens. Systemic workup came positive for skin Tuberculosis test, and presumed intraocular tuberculosis treatment was started accordingly. Inflammation persisted, so a repeat vitrectomy was performed with removal of the lens implant with the capsule, and this time bedside culture inoculation was performed in operating room, revealing Pseudomonas infection. Delayed-onset postoperative endophthalmitis typically progresses slowly and therefore can be confused with uveitis and treated with steroid and immunosuppressant treatment regimes. Our case confirms both the value of immediate bacterial inoculation and the necessity of aggressive surgical treatment in chronic postoperative endophthalmitis cases.
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    Effect of breast milk and sucrose on pain and perfusion index during examination for retinopathy of prematurity
    (2021) Turan, Ozden; Akkoyun, Imren; Ince, Deniz Anuk; Doganay, Beyza; Tugcu, A. Ulas; Ecevit, Ayse; 0000-0002-7707-1881; 0000-0002-2860-7424; 0000-0002-4369-2110; 31203685; 0000-0002-7707-1881; AAK-7713-2021; I-6746-2016
    Objective: The objective of this study is to investigate the effect of breast milk and sucrose on pain scores and perfusion index (PI) and to evaluate the alteration in pain and PI during retinopathy of prematurity (ROP) examination. Methods: This prospective randomized controlled study was conducted with preterm infants who were born in our hospital, hospitalized in the neonatal intensive care unit and whose gestational week was <32 weeks and birth weight was <1500 g. The preterm infants who would undergo ROP examination were allocated to three groups according to simple randomization method as follows: group 1: only local anesthetic eye drops, proparacaine HCl ophthalmic solution 0.5%, group 2: proparacaine HCl ophthalmic solution 0.5% plus breast milk, and group 3: proparacaine HCl ophthalmic solution 0.5% plus sucrose 24%. Postductal PI, transcutaneous oxygen saturation and heart rate (HR) values were measured before the eye examination (0), at the 30th, 60th, and 90th seconds (s) of the eye examination and 30 s after lasting of the examination in all infants. Pain was evaluated using Neonatal Infant Pain Scale (NIPS) during the examination. Results: Fifty-one preterm neonates were prospectively enrolled into the study. The HR was higher during and after the examination in all infants according to before the examination (p < .001). Transcutaneous oxygen saturation values significantly decreased during the examination in breast milk and sucrose groups (p = .001 and <.001, respectively). While PI was found to be lower at the 60th s compared to the 30th s of the examination in the proparacaine HCl group, no difference was found between the values before and after the examination. Perfusion index was found to significantly decrease during and after the examination compared to the values before the examination in the breast milk group. Perfusion index values were determined to significantly decrease at the 30th and 60th s of the examination in the sucrose group. The NIPS scores during the examination were determined to be higher compared to the NIPS scores before the examination in all groups (p< .001). In the intergroup comparisons, the NIPS scores were found to be higher in the sucrose group compared to the proparacaine HCl group at the 60th s of the examination and higher than that in the breast milk group at the 90th s of the examination (p = .02 and p = .01, respectively). Conclusions: The present study indicates that alterations may be seen in PI during the ROP examination; in other words, peripheral tissue perfusion could be affected. We consider that eye examination is a very painful procedure, and administering breast milk, sucrose or local anesthetic is not sufficient for reducing pain.
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    Enhanced Depth Imaging Optical Coherence Tomography in Patients with Different Phases of Behcet's Panuveitis
    (2017) Yesilirmak, Nilufer; Lee, Wen-Hsiang; GurGungor, Sirel; Yaman Pinarci, Eylem; Akkoyun, Imren; Yilmaz, Gursel; https://orcid.org/0000-0002-8632-2873; https://orcid.org/0000-0001-6178-8362; https://orcid.org/0000-0002-2860-7424; https://orcid.org/0000-0002-2589-7294; 28237149; AAD-7299-2020; AAD-5967-2021; AAK-7713-2021; AAK-6987-2021
    OBJECTIVE: To evaluate the changes in choroidal thickness (CT) at 13 different points between "active," "remission," and "end-stage" phase of Behcet's panuveitis and compare this with the age, sex, and spherical equivalent matched healthy controls using enhanced depth imaging optical coherence tomography. DESIGN: Prospective study. PARTICIPANTS: Eighty-five eyes of 45 patients with Behcet's panuveitis (19 eyes with active phase, 48 eyes with remission phase, and 18 eyes with end-stage phase) and 84 eyes of 42 controls were enrolled in this study. METHODS: CT measurements were obtained beneath the fovea and at 500-mu m intervals for 3 mm nasal and temporal to the centre of the fovea. Correlation analyses were calculated to assess the relationship of the CT with age and disease duration. RESULTS: At all 13 measurement points, CT was significantly thinnest in end-stage-phase eyes and thickest in active-phase eyes (p < 0.01). CT was thicker in remission-phase eyes compared with control eyes at foveal and perifoveal points, but the trend was not statistically significant. The mean CT at each of the 13 measured points showed a negative correlation with age and disease duration (p < 0.01). CONCLUSIONS: Submacular CT, as measured by enhanced depth imaging optical coherence tomography, was significantly reduced in eyes with Behcet's panuveitis in the end-stage phase and increased in those in the active phase.
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    Favorable outcomes in the treatment of aggressive posterior retinopathy of prematurity
    (2019) Sahinoglu-Keskek, Nedime; Akkoyun, Imren; Torer, Birgin; 0000-0001-8544-103X; 31718282; T-4258-2017
    Objectives: To report the results of intravitreal ranibizumab injection as primary therapy in aggressive posterior retinopathy of prematurity, the process of the disease, and the additive treatments performed. Methods: This retrospective case review included 15 eyes of 8 premature babies with aggressive posterior retinopathy of prematurity who were initially treated with intravitreal ranibizumab injection. The documented data were gestational age, birth weight, gender, postmenstrual age at intravitreal ranibizumab injection, zone of retinopathy of prematurity, reactivation time of disease, iris neovascularization, retinal hemorrhage, anatomical outcome, and additional treatment. Results: Median gestational age at birth was 26 (range, 23-27)weeks, birth weight was 730 (range, 550-970)g, and postconceptional age at aggressive posterior retinopathy of prematurity diagnosis and intravitreal ranibizumab injection was 35 (range, 33-35)weeks. Intravitreal ranibizumab injection was performed as primary treatment. Two eyes necessitated a second intravitreal ranibizumab injection. The reactivation of retinopathy of prematurity was 5 (range, 3-7)weeks after intravitreal ranibizumab injection. Recurrence of the disease in Zone II was treated with laser photocoagulation. A favorable outcome was obtained in all eyes (100%). Conclusion: Aggressive posterior retinopathy of prematurity is a serious, rapidly progressing form of retinopathy of prematurity that requires quick and proper management. This study indicates that primary treatment with ranibizumab and laser photocoagulation on recurrence provide favorable anatomical outcomes.
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    Hedgehog Signal Defect Leading to Familial Exudative Vitreoretinopathy-Like Disease and Gastrointestinal Malformation
    (2022) Keskek, Nedime Sahinoglu; Akkoyun, Imren; Temiz, Abdulkerim; Kutuk, Ozgur; https://orcid.org/0000-0001-8544-103X; https://orcid.org/0000-0002-2860-7424; https://orcid.org/0000-0001-9854-7220; 35770050; T-4258-2017; AAK-7713-2021
    Objectives: The aim of the study was to present a new generic association presenting with gastrointestinal tract malformations (GTMs) and familial exudative vitreoretinopathy (FEVR)-like disease and review the genetics of Hedgehog signaling. Materials and Methods: Three neonates were diagnosed with FEVR-like retinal vascular disease upon routine ophthalmological examination during hospitalization in the neonatal surgical intensive care unit for GTMs. Generic analysis of the neonates was performed. Results: Gestational age of the neonates was 39, 38, and 39 weeks and birth weights were 3,500, 3,600, and 3,300 grams, respectively. All six eyes of the three infants were treated by laser photocoagulation. Recurrence was not seen in any of the eyes. Genetical analysis of all the neonates diagnosed with FEVR-like disease revealed defects in the Hedgehog pathway. Conclusion: FEVR is a genetically well-defined retinal vascular disease. The current study is the first to show an association between FEVR-like retinal vascular disease and GTMs. This study demonstrates the importance of the Hedgehog pathway in retinal vascular and gut development.
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    Impact of Platelet Count in Retinopathy of Prematurity
    (2020) Keskek, Nedime Sahinoglu; Gulcan, Hande; Yilmaz, Gursel; Akkoyun, Imren; 0000-0001-8544-103X; 33389935; T-4258-2017
    Objectives: The aim of the study was to investigate the risk factors for retinopathy of prematurity (ROP), including platelet count. Materials and Methods: This retrospective study analyzed 137 infants in 3 subgroups: no ROP; mild RAP, and severe ROP requiring laser treatment (type 1 ROP). A retrospective review of records was performed and statistical analysis of possible risk factors for ROP including platelet count was evaluated by using logistic regression. Results: Birth weight (BW), gestational age (GA), and low platelet count in the first week after birth were significant risk factors for developing ROP (p=0.038, 0.02, and 0.004, respectively). BW, GA, ventilation, and lower platelet count were associated with progression to type 1 ROP (p=0.004; 0.027, and 0.021, respectively). Conclusion: Lower platelet count in the first week after birth is a risk factor for ROP development in addition to the previously established factors of ventilation need, low BW, and low GA.
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    Macular Imaging Characteristics in Children with Myelinated Retinal Nerve Fiber and High Myopia Syndrome
    (2023) Sezenoz, Almila Sarigul; Oto, Sibel; Akkoyun, Imren; Bayar, Sezin Akca; Yilmaz, Gursel; Colak, Meric Yavuz; 0000-0003-0171-4200; 0000-0002-2860-7424; 0000-0001-5109-755X; 0000-0002-7030-5454; 0000-0002-0294-6874; 37602641; AAJ-4668-2021; AAK-7713-2021; AAJ-2406-2021; AAJ-4860-2021; AAA-4360-2021
    Objectives: To investigate the macular imaging features in patients with unilateral myelinated retinal nerve fiber (MRNF) and high myopia syndrome. Materials and Methods: Six patients with unilateral MRNF and high myopia syndrome and 13 myopic controls were enrolled in this study. Spectral domain (SD) optical coherence tomography (OCT), SD enhanced depth imaging OCT, and OCT angiography (OCTA) imaging results of MRNF-affected eyes were compared with the fellow eyes and myopic controls. Results: All patients had abnormal foveal reflex and/or ectopia. No significant difference in retinal thickness parameters were noted between the groups. In OCT scans, posterior vitreous detachment (PVD) was observed in 4 out of the 6 MRNF-affected eyes. Regarding OCTA parameters, only a significant increase in acircularity index was noted in myelinated eyes (p=0.01). Conclusion: All patients demonstrated normal foveal contours, macular structure, and OCTA features except for a higher acircularity index. The incidence of PVD was notably increased in the myelinated eyes.
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    Macular Vessel Density Measurement in Pediatric Renal and Liver Transplant
    (2022) Sezenoz, Almila Sarigul; Tortumlu, Gokhan; Akkoyun, Imren; Oto, Sibel; Haberal, Mehmet; 0000-0002-2860-7424; 0000-0002-3462-7632; 0000-0003-0171-4200; 0000-0002-7030-5454; 35570609; AAK-7713-2021; AAJ-8097-2021; AAJ-4668-2021; AAJ-4860-2021
    Objectives: Microcirculatory dysfunction is known to be associated with organ failure and increased mortality in transplant patients. Noninvasive monitorization of retinal structures of the eye could be a predictor for systemic microvasculature in these patients. Therefore, in this study we aimed to evaluate the retinal microvascular changes in pediatric patients who had undergone liver or renal transplant surgery, using optical coherence tomography angiography. Materials and Methods: The medical records of pediatric patients who had liver or renal transplant in the past 10 years were reviewed. The macular vessel density parameters were obtained by optical coherence tomography angiography (Avanti RTVue XR). The results were compared with the age-matched, sex-matched, and spherical equivalent-matched healthy participants (control group). The IBM SPSS (version 25.0) statistics program was used for data analysis. Results: We included 32 eyes of 16 liver transplant patients, 20 eyes of 10 renal transplant patients, and 64 eyes of 32 healthy participants (control group). Superficial macular whole image, superficial perifoveal, and deep foveal vessel densities were found to be lower in the liver transplant group compared with the healthy control group (P = .02, P = .01, and P = .01, respectively). Superficial foveal, deep macular whole image, deep foveal, and deep perifoveal vessel densities were found to be lower in the renal transplant group compared with the healthy control group (P = .03, P = .04, P = .01, and P = .02, respectively). Conclusions: Macular vessel density measurements are affected in pediatric renal and liver transplant patients. In those patients, retinal optical coherence tomography and optical coherence tomography angiography measurements may provide a noninvasive window to the microcirculation.
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    Platelet distribution width is a predictive marker for development of severe retinopathy of prematurity
    (2020) Sahinoglu-Keskek, Nedime; Akkoyun, Imren; Cetinkaya, Bilin; 0000-0001-8544-103X; 0000-0003-0866-7339; 33235344; T-4258-2017; AAK-7713-2021; AAF-1346-2021
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    Refractive Outcome Comparison Between Vitreomacular Interface Disorders After Phacovitrectomy
    (2017) Ercan, Zeynep Eylul; Akkoyun, Imren; Pinarci, Eylem Yaman; Yilmaz, Gursel; Topcu, Hulya; https://orcid.org/0000-0002-2860-7424; https://orcid.org/0000-0002-2589-7294; https://orcid.org/0000-0002-5259-0204; 10.1016/j.jcrs.2017.06.034; AAK-7713-2021; AAK-6987-2021
    Purpose: To compare the refractive accuracy of intraocular lens (IOL) power calculations between patients with vitreomacular interface disorders who had phacovitrectomy for vitreomacular traction (VMT), epiretinal membranes (ERM), and macular holes. Setting: Baskent University Department of Ophthalmology, Ankara, Turkey. Design: Retrospective case series. Methods: Refraction results 8 weeks postoperatively were compared between phacovitrectomy (3 study groups comprising eyes with VMT with intrafoveal pseudocysts, ERM, or medium-to-large macular holes) and phacoemulsification (control group comprising eyes having phacoemulsification only). The IOLMaster 700 partial coherence interferometry (PCI) device and Haigis formula were used for all calculations. Results: This study included 100 eyes (100 patients), 25 in each of the 4 groups. There was no statistically significant difference in axial length (AL) between the groups (P = .305). Differences in the pre-operative macular thickness were statistically significant between all groups except between the macular hole and VMT groups. Most eyes (92%) in the VMT and macular hole groups and all eyes in the VMT and phacoemulsification groups achieved a final refraction within +/- 1.00 diopter of the refractive aim. The mean prediction error and the mean absolute error did not differ significantly between the groups. In all groups, there was no significant correlation between prediction error and age, AL, preoperative refractive error, or preoperative or postoperative macular thickness (P > .05). Conclusions: The IOL power calculation with PCI yielded no difference in postoperative refraction errors between the vitreomacular interface disorders. There was no correlation with preoperative refraction, age, or preoperative or postoperative macular thickness. (c) 2017 ASCRS and ESCRS
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