Huseyin Simavli

Diagnostic Capability of Peripapillary Retinal Thickness in Glaucoma Using 3D Volume Scans

PURPOSE To determine the diagnostic capability of spectral-domain optical coherence tomography (SD OCT) peripapillary retinal thickness (RT) measurements from 3-dimensional (3D) volume scans for primary open-angle glaucoma (POAG). DESIGN Cross-sectional study. METHODS setting: Institutional. study population: 156 patients (89 POAG and 67 normal subjects). observation procedures: One eye of each subject was included. SD OCT peripapillary RT values from 3D volume scans were calculated for 4 quadrants of 3 different sized annuli. Peripapillary retinal nerve fiber layer (RNFL) thickness values were also determined. main outcome measures: Area under the receiver operating characteristic curve (AUROC) values, sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios. RESULTS The top 5 RT AUROCs for all glaucoma patients and for a subset of early glaucoma patients were for the inferior quadrant of outer circumpapillary annulus of circular grid (OCA) 1 (0.959, 0.939), inferior quadrant of OCA2 (0.945, 0.921), superior quadrant of OCA1 (0.890, 0.811), inferior quadrant of OCA3 (0.887, 0.854), and superior quadrant of OCA2 (0.879, 0.807). Smaller RT annuli OCA1 and OCA2 consistently showed better diagnostic performance than the larger RT annulus OCA3. For both RNFL and RT measurements, best AUROC values were found for inferior RT OCA1 and OCA2, followed by inferior and overall RNFL thickness. CONCLUSION Peripapillary RT measurements from 3D volume scans showed excellent diagnostic performance for detecting both glaucoma and early glaucoma patients. Peripapillary RT values have the same or better diagnostic capability compared to peripapillary RNFL thickness measurements, while also having fewer algorithm errors.

Macula and retinal nerve fiber layer in migraine patients: analysis by spectral domain optic coherence tomography.

Abstract Aim: Investigating the retinal nerve fiber layer (RNFL), macular and ganglion cell complex thickness in eyes of migraine patients using optical coherence tomography. Methods: The study was designed as an observational cross-sectional study. 50 patients with migraine (30 patients with aura and 20 patients without aura) and 50 healthy volunteers were included. Optical coherence tomography was performed with Optovue technology. The fast RNFL thickness (3.4) scan, MM5, and GCC acquisition protocols were used. Results: There was no statistically significant difference in retinal thickness in any of the quadrants between the control group and the migraine patients (p > 0.05). The average RNFL thickness (110.50 vs 102.84 microns, p = 0.03) was significantly thinner in migrainers as compared to the control. The ANOVA did not reveal any significant difference between migrainers with aura, migrainers without aura, and the control group. The VAS (visual analogue scale) score of migraine patients was not statistically significantly correlated with any of the parameters, while the length of migraine history was negatively correlated with the average RNFL thickness (r = −0.32, p = 0.03). Conclusıon: The average RNFL thickness in the migraine patients was found to be thinner than that in the control group. In addition, we found a negative weak correlation between length of migraine history and the average RNFL thickness, supporting the possible association between these pathologies.

Refractive Error May Influence Mesopic Pupil Size

Purpose: To identify factors which affect mesopic pupil diameter in refractive surgery patients. Setting: This retrospective study was performed at the 1st Ophthalmology Clinic in Ankara Ataturk Training and Research Hospital, Ankara, Turkey. Methods: Medical records of 412 refractive surgery candidates who applied between 2006 and 2008 were reviewed. Detailed ophthalmological examination data were obtained from medical records. Pupil size measurements were performed with a COAS Ocular Wavefront analyzer in mesopic conditions. Relationship between mesopic pupil diameter and age, sex, spherical refractive error (D), magnitude of astigmatism (D), type of astigmatism, spherical equivalent, and average keratometry were analyzed by means of univariate and multivariate regression analyses. Results: Mean mesopic pupil diameter was 6.19 ± 0.88 mm. Mean pupil diameter (mean ± standard deviation) was 5.70 ± 1.01 in hypermetropia, 6.04 ± 0.79 mm in mixed astigmatism, and 6.33 ± 0.82 mm in myopia. The difference in mean mesopic pupil diameters between myopes and hypermetropes was statistically significant (p = 0.001). However, differences with regard to mean pupil diameters between myopes and mixed astigmatism (p = 0.660) and between hypermetropes and mixed astigmatism (p = 0.109) were not significant. Mean pupil diameter was 6.00 ± 0.99 mm in against the rule astigmatism, 5.96 ± 0.84 mm in oblique astigmatism, and 6.27 ± 0.84 mm in with the rule astigmatism. Mean mesopic pupil diameter in with the rule astigmatism group was higher than oblique astigmatism group. Spherical refractive error (r = -0.213, p = 0.001), cylindrical refractive error (0.197, p = 0.001), and age (r = −0.341, p = 0.001) showed correlation with pupil diameter. Conclusions: This study showed that age and magnitude of both spherical and cylindrical refractive error are the most determinative factors on mesopic pupil size.

Inhibitory effects of regorafenib, a multiple tyrosine kinase inhibitor, on corneal neovascularization.

AIM To evaluate the inhibitory effects of regorafenib (BAY 73-4506), a multikinase inhibitor, on corneal neovascularization (NV). METHODS Thirty adult male Sprague-Dawley rats weighing 250-300 g, were used. Corneal NV was induced by NaOH in the left eyes of each rat. Following the establishment of alkali burn, the animals were randomized into five groups according to topical treatment. Group 1 (n = 6) received 0.9% NaCl, Group 2 (n = 6) received dimethyl sulfoxide, Group 3 (n = 6) received regorafenib 1 mg/mL, Group 4 (n =6) received bevacizumab 5 mg/mL and Group 5 (n = 6) received 0.1% dexamethasone phosphate. On the 7d, the corneal surface covered with neovascular vessels was measured on photographs as the percentage of the corneas total area using computer-imaging analysis. The corneas obtained from rats were semiquantitatively evaluated for caspase-3 and vascular endothelial growth factor by immunostaining. RESULTS A statistically significant difference in the percent area of corneal NV was found among the groups (P <0.001). Although the Group 5 had the smallest percent area of corneal NV, there was no difference among Groups 3, 4 and 5 (P >0.005). There was a statistically significant difference among the groups in apoptotic cell density (P = 0.002). The staining intensity of vascular endothelial growth factor in the epithelial and endothelial layers of cornea was significantly different among the groups (P <0.05). The staining intensity of epithelial and endothelial vascular endothelial growth factor was significantly weaker in Groups 3, 4 and 5 than in Groups 1 and 2. CONCLUSION Topical administration of regorafenib 1 mg/mL is partly effective for preventing alkali-induced corneal NV in rats.

Effects of intracameral use of adrenalin solution with preservative on corneal endothelium

Objective: To evaluate the effects of injection of 1:100,000 dilution adrenalin with sodium bisulfite preservative on the corneal endothelium in phacoemulsification cataract surgery. Methods: This retrospective study comprised 70 patients with age-related cataracts who had undergone phacoemulsification cataract surgery with intraocular lens (IOL) implantation without any surgical complications. In the adrenalin group, patients with intraoperative intracameral adrenalin use were included. The intracameral adrenalin was composed of 1 mL of 1:100,000 dilution adrenalin with sodium bisulfite preservative. The control group included patients who underwent surgery without any intracameral adrenaline use. There were 36 patients in the adrenalin group and 34 patients in the control group. Corneal endothelial density, endothelial cell morphology, and endothelial cell area were measured via specular microscopy both preoperatively and 3 months after surgery. The 2 groups were compared with regard to changes in specular microscopy measurements. Results: The mean (± standard deviation) age was 66.51 ± 8.32 years in the adrenalin group and 67.58 ± 7.83 years in the control group. The difference in age between the 2 groups was not significant (p = .611). The preoperative mean corneal endothelial cell density was 2,270 ± 286 cells/mm2 in the adrenalin group and 2,226 ± 260 cells/mm2 in the control group, and the difference between the 2 groups was not statistically significant (p = .550). In the adrenalin group, the postoperative mean corneal endothelial cell density was 2,191 ± 268 cells/mm2. Although the postoperative mean cell density was lower than the preoperative mean cell density, the difference between the 2 measurements was not statistically significant (p = .117). In the control group, the postoperative mean corneal endothelial cell density was 2,169 ± 272 cells/mm2, and the difference between the preoperative and postoperative measurements was not statistically significant (p = .161). Comparisons of postoperative specular microscopy measurements between the adrenalin and control groups with regard to cell density, cell sizes, and cell shapes showed that there were no statistically significant differences in comparison of all parameters between the 2 groups. Conclusions: Intracameral injection of 1:100,000 dilution adrenalin with sodium bisulfite preservative is not toxic to corneal endothelium.

Facilitating Glaucoma Diagnosis With Intereye Retinal Nerve Fiber Layer Asymmetry Using Spectral-Domain Optical Coherence Tomography.

Purpose:To test whether increased intereye retinal nerve fiber layer (RNFL) asymmetry may be indicative of glaucoma. To determine the best statistical methods and intereye RNFL cutoffs for differentiating between normal and glaucoma subjects to better alert clinicians to early glaucomatous damage. Methods:Sixty-six primary open-angle glaucoma (OAG) and 40 age-matched normal subjects had both eyes imaged at the Massachusetts Eye and Ear Infirmary with a commercially available spectral-domain optical coherence tomography (OCT) machine. Statistical methodologies were used to find cutoffs that achieved the best sensitivities and specificities for differentiating OAG from normal subjects. Results:Intereye RNFL asymmetry for global average, all quadrants, and all sectors was significantly greater in OAG than normal subjects. Intereye RNFL asymmetry for global average showed the greatest statistical difference (P<0.001) between OAG (23.64±14.90 &mgr;m) and normal eyes (3.58±3.96 &mgr;m), with 6.60 times greater asymmetry in OAG eyes. The inferior quadrant showed the second greatest difference, with 3.91 times greater asymmetry in OAG eyes. Using a statistically determined cutoff of 6.0 &mgr;m as abnormal, intereye RNFL asymmetry for global average achieved a sensitivity of 74.24% and specificity of 90% in differentiating between normal and OAG subjects, achieving a better combination of sensitivity and specificity than intereye RNFL asymmetry of any quadrant or sector. Conclusions:Intereye RNFL asymmetry may be a useful clinical OCT measurement to provide quantitative assessment of early glaucomatous damage. Newly developed algorithms for intereye RNFL asymmetry may improve the ability to detect glaucoma.

Comprehensive Three-Dimensional Analysis of the Neuroretinal Rim in Glaucoma Using High-Density Spectral-Domain Optical Coherence Tomography Volume Scans

Purpose To describe spectral-domain optical coherence tomography (OCT) methods for quantifying neuroretinal rim tissue in glaucoma and to compare these methods to the traditional retinal nerve fiber layer thickness diagnostic parameter. Methods Neuroretinal rim parameters derived from three-dimensional (3D) volume scans were compared with the two-dimensional (2D) Spectralis retinal nerve fiber layer (RNFL) thickness scans for diagnostic capability. This study analyzed one eye per patient of 104 glaucoma patients and 58 healthy subjects. The shortest distances between the cup surface and the OCT-based disc margin were automatically calculated to determine the thickness and area of the minimum distance band (MDB) neuroretinal rim parameter. Traditional 150-μm reference surface–based rim parameters (volume, area, and thickness) were also calculated. The diagnostic capabilities of these five parameters were compared with RNFL thickness using the area under the receiver operating characteristic (AUROC) curves. Results The MDB thickness had significantly higher diagnostic capability than the RNFL thickness in the nasal (0.913 vs. 0.818, P = 0.004) and temporal (0.922 vs. 0.858, P = 0.026) quadrants and the inferonasal (0.950 vs. 0.897, P = 0.011) and superonasal (0.933 vs. 0.868, P = 0.012) sectors. The MDB area and the three neuroretinal rim parameters based on the 150-μm reference surface had diagnostic capabilities similar to RNFL thickness. Conclusions The 3D MDB thickness had a high diagnostic capability for glaucoma and may be of significant clinical utility. It had higher diagnostic capability than the RNFL thickness in the nasal and temporal quadrants and the inferonasal and superonasal sectors.

Corneal white-to-white distance and mesopic pupil diameter.

AIM To study the relationship between corneal white-to-white (WTW) distance and mesopic pupil diameter. METHODS This study is composed of 30 cases that underwent photorefractive keratotomy (PRK). Pupil size measurements were performed with Schwind ORK wavefront analyzer in mesopic conditions. WTW distance was measured with a measuring caliper. Also, A-scan ultrasound examination was performed in all patients. The relationship among the mesopic pupil diameter and age, sex, axial length, lens thickness, anterior chamber depth(ACD), horizontal WTW distance, vertical WTW distance, spherical equivalent, and average keratometry were analyzed with univariate and multivariate regression analysis. RESULTS Mean pupil diameter was (6.39±0.80)mm (range: 3.70mm-7.73mm). Horizontal WTW distance measurements were between 11.00mm and 12.50mm and mean horizontal WTW distance was (11.79±0.43)mm. On the other hand, vertical WTW distances ranged between 10.00mm and 13.00mm, and their mean was (11.42±0.72)mm. Bivariate correlation between pupil diameter and other variables showed that the axial length, ACD, spherical equivalent, and horizontal WTW distance had a moderate correlation with mesopic pupil diameter. Multiple regression analysis revealed that spherical equivalent and horizontal WTW distances were significantly associated with mesopic pupil diameter (R=0.598, R(2)=0.358 P=0.02). CONCLUSION This study shows that mesopic pupil diameter is closely related to horizontal WTW distance. These two factors must be taken in consideration together in preoperative ablation zone planning.

Causes of Decentration After Laser-Assisted Subepithelial Keratectomy

BACKGROUND AND OBJECTIVE To determine important factors causing decentration after laser-assisted subepithelial keratectomy (LASEK). PATIENTS AND METHODS A total of 223 cases (446 eyes) were evaluated after LASEK using corneal topography to determine the amount of decentration. Decentration and pupillary offset values and their components on the nasal, temporal, superior, and inferior axes were analyzed with the t test and the two-way repeated measures analysis of variance test in patients with myopia or hypermetropia. Correlation analysis between the amount of decentration and the possible determinative variables (age, gender, spherical refractive error, magnitude of astigmatism, spherical equivalent, average keratometry, mesopic pupil diameter, decentration, and pupillary offset) were performed. RESULTS Although decentration up to 0.99 mm was observed, mean decentration was 0.26 ± 0.16 mm. Alternatively, pupillary offset values were higher and the mean pupillary offset was 0.28 ± 0.16 mm. In myopia, mean total decentration was significantly less than hyperopia (P = .001). The inferior component of decentration was higher than the other locations in both myopia and hypermetropia. The nasal component of pupillary offset was highest among others. When all cases were included in the analysis, Pearson correlation analysis showed a statistically significant correlation between decentration and presence of hyperopia (r = 0.162 and P =.001) and amount of pupillary offset (r = 0.296 and P = .001). CONCLUSION Mean decentration was higher in hyperopia than in myopia. Most of the decentration may be attributed to inferior decentration. Pupillary offset values were the factor most significantly correlated to the amount of decentration in all cases.

Short-term effects of intravitreal triamcinolone acetonide injection on ocular blood flow evaluated with color Doppler ultrasonography

AIM To evaluate the changes in ocular blood flow with color Doppler ultrasonography (CDU) after intravitreal triamcinolone acetonide (IVTA) injection. METHODS A total of 46 patients who underwent IVTA (4 mg/0.1 mL) injection for diabetic macular edema (DME) (n=22), central retinal vein occlusion (CRVO) (n=12) and choroidal neovascular membrane (CNVM) (n=12) were included in the study. Peak systolic velocity (PSV), end diastolic velocity (EDV) and resistivity index (RI) were measured from the ophthalmic artery (OA), the central retinal artery (CRA) and the posterior ciliary artery (PCA) of each patient with CDU before, at the end of the first week and at the end of the first month following IVTA injection. RESULTS In the DME group, PSV of OA at the first of the first month (mean±SD) (37.48±10.87 cm/s) increased compared to pre-injection value (31.39±10.84 cm/s) (P=0.048). There was a statistically significant decrease (P=0.049) in PSV of CRA at the end of the first month (7.97±2.67 cm/s) compared to the pre-injection (9.47±3.37 cm/s). There was not any statistically significant difference on the other parameters in the DME group. Also, there was not any statistically significant difference on the ocular blood flow values in the CRVO and CNVM groups. CONCLUSION We observed that 4 mg/0.1 mL IVTA increased PSV of OA and decreased PSV of CRA in DME patients and did not have any effect on ocular blood flow values of CRVO and CNVM patients.