Emre Güler

Dexamethasone Intravitreal Implant for Chronic Diabetic Macular Edema Resistant to Intravitreal Bevacizumab Treatment

Abstract Purpose: To evaluate the safety and efficacy of intravitreal dexamethasone implant (Ozurdex) in patients with chronic diabetic macular edema (DME) resistant to prior intravitreal bevacizumab (IVB) treatment. Materials and Methods: Thirty eyes of 30 patients were administered intravitreal Ozurdex and examined at baseline and 1, 3, and 6 months postinjection in this prospective study. Main outcomes were the best corrected visual acuity (BCVA, logMAR), central foveal thickness (CFT), mean cube volume (MCV), and intraocular pressure (IOP). Patients had a CFT over 275 µm (measured by OCT) and were unresponsive to 3 consecutive IVB injections. All data are presented as mean ± standard deviation. Results: The mean BCVA significantly increased from 0.56 ± 0.38 to 0.41 ± 0.27 (p < 0.001), and 0.44 ± 0.28 (p = 0.008) at 1 and 3 months, respectively. At months 1, 3, and 6, the mean CFT significantly decreased from 517 ± 136 µm at baseline, to 290 ± 60 µm (p < 0.001), 314 ± 88 µm (p < 0.001) and 411 ± 126 µm (p = 0.01), respectively. However, the mean CFT (p < 0.001) and MCV (p = 0.01) significantly increased and BCVA significantly decreased (p = 0.04) at 6 month compared to 3 month. Compared to baseline, IOP increased significantly at 1 week (p = 0.01), 1 month (p = 0.01) and 3 months (p = 0.04). However eyes with IOP higher than 21 mmHg were treated and well controlled with topical anti-glaucoma monotherapy. Macular edema recurrence occurred in 25 eyes (CFT ranged from 321 µm to 800 µm) at 6 months. Conclusion: Dexamethasone intravitreal implant may be an effective and safe alternative in treatment of chronic DME nonresponsive to regular IVB. However, its therapeutic efficacy decreases between the third and sixth months following the injection.

Repeatability and reproducibility of Galilei measurements in normal keratoconic and postrefractive corneas.

OBJECTIVE To assess the repeatability and reproducibility of the anterior segment measurements performed with a dual Scheimpflug analyzer (Galilei) in normal, keratoconic and post-refractive surgery corneas. METHODS To evaluate the repeatability, two additional measurements were performed by the first examiner. To assess reproducibility, this was later followed by a single reading by the second examiner. The following parameters were recorded and evaluated in this study; central corneal thickness (CCT), thinnest corneal thickness (TCT), mean total corneal power (TCP) in central (0-4mm), mean posterior corneal power (PCP) in central (0.5-2mm), anterior and posterior elevation (best fit sphere [BFS]) in central 8mm anterior and posterior eccentricity (ɛ(2)) in central 8mm. Repeatability and reproducibility for each corneal parameter was assessed using the Bland-Altman analysis. RESULTS Each of the three groups was consisted of 20 subjects (totally 60 patients, 30 men and 30 women). The 95% LoA for repeatability was very small, indicating small discrepancies between measurements related to CCT. Acceptable repeatability was also achieved for the other parameters in each group. However, the 95% LoA for value TCP was larger in keratoconic eyes. The 95% LoA for reproducibility was also very small, and acceptable for all measured parameters in each group. In addition, the 95% LoA was larger for the measurement of CCT and TCT for postrefractive corneas. CONCLUSIONS The anterior segment measurements provided by Galilei showed good repeatability and reproducibility for normal, keratoconic and postrefractive corneas.

Evaluation of Choroidal Thickness in Amblyopia Using Enhanced Depth Imaging Optical Coherence Tomography

ABSTRACT Purpose: To evaluate the choroidal thickness (CT) in hyperopic anisometropic amblyopic eyes, fellow non-amblyopic eyes, and age-matched normal eyes, using spectral-domain optical coherence tomography (SD-OCT). Materials and methods: In total 53 subjects (17.8 ± 11.0 years, mean ± SD) with hyperopic anisometropic amblyopia (AE) and 53 age-matched controls (17.7 ± 11.0 years) were included in this prospective study. Each subject underwent a dilated eye examination, cycloplegic refraction and axial length (AL) measurement using Nidek AL-Scan optical biometer (Nidek CO, Aichi, Japan). The CT of subfoveal area and at a radius of 1 and 3 mm around the fovea was determined using the enhanced depth imaging program of a SD-OCT (Cirrus HD OCT, Carl-Zeiss Meditec, Dublin, CA). CT, AL and spherical equivalent refraction (SER) of the amblyopic eyes were compared to that of the fellow and control eyes. Results: The mean subfoveal CT was 305.6 ± 26.0 µm in the amblyopic eyes, 282.6 ± 30.7 µm in the fellow eyes and 280.1 ± 8.8 in the control eyes. The subfoveal choroid in amblyopic eyes was significantly thicker than that of the fellow eyes and control eyes (p <  0.001). There was a significant negative correlation between the subfoveal CT and the AL in amblyopic (r = −0.298, p=0.03) eyes but not in the control and fellow eyes. Conclusions: The subfoveal choroid of eyes with hyperopic AE is significantly thicker than that of the fellow eye and the age-matched controls. Hence, CT seems to be effected in AE.

Effect of smoking on retina nerve fiber layer and ganglion cell-inner plexiform layer complex

Abstract Purpose: The aim of this study is to show the effects of smoking on retina layers, especially retina nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer complex (GCIPL). Materials and methods: Participants smoking for more than 10 years at least 1 pack of cigarettes a day and a control group, both including participants between ages of 20 and 50 years with no other systemic or ocular diseases were studied. After normality tests, an independent sample t test was used to analyze the differences in age, sex, spherical equivalent (SE), intraocular pressure (IOP), axial length (AL), GCIPL and RNFL values between the groups. Results: There were 44 participants in each group. There were 32 (62.5%) men and 12(37.5%) women in smokers and 36 (77.88%) men and 8 (22.22%) women in control group. Mean ages were 39.85 ± 8.41 and 38.66 ± 10.47 years, mean spherical equivalent (SE) values were −0.15 ± 0.4 and 0 ± 0.29 dioptries in smokers and control groups, respectively. The IOP, AXL, GCIPL and RNFL values were 17.58 ± 3.41 mmHg, 23.69 ± 0.56 mm, 84.3 ± 5.83 μm and 92.3 ± 3.51 μm in the smokers group and 18.5 ± 2.91 mmHg, 23.45 ± 0.72 mm, 86.11 ± 8.02 μm and 97.66 ± 8.23 μm in the control group. The inferior, superior, nasal and temporal values of RNFL quadrants were 123.18 ± 26.14, 117.05 ± 5.51, 64.95 ± 8.67 and 63.5 ± 6.88 μm in the smokers group and 130.81 ± 11.8, 123.55 ± 11.03, 72.44 ± 9.84 and 58.44 ± 7.48 μm in the control group. There were no significant difference of age, sex, SE, IOP, AXL and GCIPL values between the smokers and control groups (p > 0.05). The mean RNFL was significantly thinner in the smokers group compared to controls (p = 0.03, independent t test). Inferior and superior quadrants of RNFL decreased in smokers group (p = 0.01 and p = 0.03, respectively) but temporal and nasal quadrants did not seem to be changed (p = 0.96 and p = 0.07, respectively). Discussion: Smoking may affect RNFL thickness but not GCIPL.

Repeatability and reproducibility of a new optical biometer in normal and keratoconic eyes

Purpose To evaluate the repeatability and reproducibility of measurements obtained by a new optical biometer (Nidek AL‐Scan) in normal eyes and keratoconic eyes. Setting Department of Ophthalmology, Turgut Özal University, Medical School, Ankara, Turkey. Design Evaluation of diagnostic technology. Methods To assess the repeatability and reproducibility of the optical biometer, 2 independent examiners performed 3 consecutive measurements. The following parameters were evaluated: central corneal thickness (CCT), anterior chamber depth, axial length (AL), corneal dioptric power in the flattest meridian (flat keratometry [K]) and in the steepest meridian (steep K), and white‐to‐white (WTW) distance. Repeatability was assessed using the within‐subject standard deviation (Sw), repeatability, and precision. Reproducibility was evaluated using the 95% limits of agreement proposed by Bland and Altman. Results Thirty healthy subjects and 27 patients with keratoconus were evaluated. Both examiners achieved high repeatability for all parameters in each group except for the steep K measurement in keratoconic eyes performed by examiner 2 (Sw = 3.341). The WTW in normal eyes and the CCT and steep K in keratoconic eyes showed less repeatability. In both groups, the smallest range of agreement was in AL measurements whereas the largest was in CCT measurements. In keratoconic eyes, the range of agreement for steep K was also greater (3.766). Conclusions The precision of the measurements obtained by the new optical biometer was high. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Normative Spectral Domain Optical Coherence Tomography Data in Healthy Turkish Children

Abstract Purpose: To determine the normative database of macular and retinal nerve fiber layer (RNFL) thickness parameters in healthy Turkish children by OCT. Methods: 318 eyes of 318 children (138 boys, 183 girls) aged between 3 and 17 years were evaluated. The children were scanned by Cirrus HD-OCT (Carl Zeiss Meditec) to measure the macula, RNFL, and optic nerve head parameters. Results: Axial length (AL) (p < 0.001, R2 = 0.08), spherical equivalent (SE) (p < 0.001, R2 = 0.12), and rim area (p < 0.001, R2 = 0.15) were the strongest predictors of RNFL thickness. All of the macular measurements were significantly related to age (p < 0.001, R2 > 5%). Average macular thickness (p < 0.01) and outer macula (p = 0.002) showed significant relationship with the AL and SE. Conclusion: This study ensures an age-adjusted pediatric normative database using OCT to diagnose and monitor macular diseases, optic nerve diseases, and glaucoma in children.

Evaluation of the retinal ganglion cell layer thickness in healthy Turkish children.

Purpose:To identify the distribution, variation, and determinants of ganglion cell–inner plexiform layer (GC-IPL) thickness in healthy Turkish children measured by high-definition optical coherence tomography (HD-OCT). Patients and Methods:This institutional study involved 296 eyes from 296 healthy children aged between 3 and 17 years. Each child underwent a dilated eye examination, cycloplegic refraction, and axial length measurement using Nidek AL-Scan optical biometer. Macular scan was used to measure the GC-IPL thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness was measured using the HD-OCT (Cirrus HD-OCT). Right eye of each subject was selected for analysis. Results:A total of 296 children (125 boys, 171 girls) were included in this study. The mean age of the children was 9.62±4.10 years (range, 3 to 17 y). The mean spherical equivalent was −0.09±1.49 D. The mean AL was 23.03±1.03 mm. The mean overall GC-IPL thickness was 83.44±5.52 &mgr;m and RNFL thickness was 96.91±10.21 &mgr;m. They were thicker than has been reported in adults. According to age-adjusted multiple regression analyses significant predictors of mean GC-IPL thickness were peripapillary RNFL thickness and AL (P<0.001). Conclusions:This study ensures a pediatric normative database of GC-IPL using spectral-domain OCT. This information may provide to diagnosis and monitoring of optic nerve diseases and glaucoma in children.

Cystoid macular edema associated with juvenile idiopathic arthritis resolved by a dexamethasone intravitreal implant.

Uveitis, glaucoma, and cystoid macular edema frequently develop in patients with juvenile idiopathic arthritis. The authors describe a case of cystoid macular edema associated with juvenile idiopathic arthritis that had not responded to intravitreal triamcinolone acetonide and bevacizumab but improved significantly following intravitreal injection with a dexamethasone 0.7 mg implant.

Brilliant blue G assisted macular surgery: the effect of air infusion on contrast recognisability in internal limiting membrane peeling

Background To evaluate the potential efficacy and safety of inner limiting membrane (ILM) staining with brilliant blue G (BBG) under air infusion. Methods 63 patients, treated by one surgeon with macular hole or idiopathic epiretinal membrane were evaluated prospectively. BBG was applied under air infusion in 38 patients (group 1), and injected into the vitreous cavity in 25 (group 2). Main outcome measures were the chromaticity difference between the stained ILM and the unstained underlying retina, anatomical–functional outcomes and complications of the surgery. Chromaticity difference was measured by an objective and quantitative analysis method to describe colour contrast strengths as they are perceived by the human eye. Anatomical and functional outcomes were assessed using optical coherence tomography (OCT), visual field analyses (VFA) and multifocal electroretinography (mfERG). Results CIELAB scores showed a significantly superior contrast for group 1 (16.72±2.36) than group 2 (10.34±1.29) (p<0.001). Visual acuity had increased in 28 eyes and remained stable in 10 eyes in group 1. In group 2, visual acuity had improved in 17 patients and remained unchanged in 8 patients. Based on postoperative OCT, anatomical success rate was 100%. During the follow-up period, mfERG and VFA demonstrated no case of BBG toxicity in either group. Cataract progression was the main postoperative complication (six eyes in group 1 and four eyes in group 2) and did not show a significant difference between the groups (p=0.45). Conclusions BBG under air infusion yields a significantly higher contrast staining and easy peeling of ILM associated with anatomical and functional improvement and no retinal toxicity after macular surgery.

Brilliant Blue G assisted Epiretinal Membrane Surgery

We report intensely staining epiretinal membrane (ERM) with Brilliant Blue G (BBG) under air for two minutes. ERM peeling was performed in 21 cases. After removal of posterior hyaloid, 0.2 mL BBG was first applied on the macula, to stain ERM under air conditions for 2 minutes. Internal limiting membrane (ILM) was intensely stained and peeled in all cases following ERM removal. In 4 cases, the ERM was also observed to be intensely stained with BBG and peeled with an ILM forceps. Postoperatively, the ganglion cell layer thickness was lower in three of the cases, however VA improved in all cases and multifocal electroretinogram revealed no toxicity. Light microscopy of ERM revealed masses of cells whereas; the ILM did not. The increased staining characteristics of ERM and ILM may be resulted from longer contact time of BBG under air pressure.