Kemal Türkyılmaz

Retinal nerve fiber layer thickness in Parkinson disease.

Abstract:Dopaminergic neuronal cells have been identified in the inner nuclear and inner plexiform layers of the human retina. The dopaminergic content of the retina is reduced in patients with idiopathic Parkinson disease (PD). These observations led us to study the retinal nerve fiber layer (RNFL) thickness in patients with PD without visual impairment compared to healthy controls using spectral-domain optical coherence tomography (SD-OCT). Eighty-two subjects, including 42 patients with PD, newly diagnosed and untreated (24 men, 18 women, age range: 47–66 years), and 40 healthy controls, were enrolled. Both eyes of patients with PD and controls were imaged with SD-OCT. The mean RNFL thickness was 77 ± 11.5 &mgr;m in PD patients and 89 ± 8.7 &mgr;m in healthy controls (P = 0.001). Selective thinning of the RNFL was found in the temporal region with mean temporal RNFL thickness of 66 ± 6.7 &mgr;m in PD patients and 75 ± 4.8 &mgr;m in controls (P = 0.001). The thickness of the RNFL is decreased in PD patients. Demonstrating progressive thinning of RNFL over time will be critical for validating optical coherence tomography as a viable biomarker of patients with PD.

Peripapillary retinal nerve fiber layer thickness in children with iron deficiency anemia.

Purpose. To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness in children with iron deficiency anemia (IDA) in comparison with healthy controls and to investigate the correlation between peripapillary RNFL thicknesses and the hematologic parameters in these subjects. Methods. Forty eyes of 40 children with a diagnosis of IDA (anemic group) and 40 eyes of 40 age- and sex-matched healthy children (control group) were enrolled in this study. Peripapillary RNFL thickness measurements were performed using Cirrus HD optical coherence tomography (OCT). Results. Mean age of each group was 11.3±2.7 years. Average RNFL and RNFLs of superior and inferior quadrants were significantly thinner in the anemic group than in the control group (p=0.006, p=0.005, and p=0.005, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of superior, inferior, and temporal quadrants were correlated with hemoglobin levels (r1=0.734, p1<0.001, r2=0.456, p2=0.005, r3=0.598, p3<0.001, r4=0.349, p4=0.037, respectively) in anemic group. Conclusions. We found that children with IDA had different peripapillary RNFL profile measured by Cirrus HD spectral-domain OCT. We caution ophthalmologists when they measure RNFL thickness in children to diagnose glaucoma or other neuro-ophthalmic disorders.

Systemic arterial stiffness in patients with pseudoexfoliation glaucoma.

Aim:To evaluate carotid-femoral pulse wave velocity (CF-PWV) values of patients with pseudoexfoliation (PEX) glaucoma in comparison with healthy subjects. Methods:Twenty-five consecutive patients with PEX glaucoma (PEXG group) and 25 controls (control group) were included in the study. CF-PWV was assessed by a noninvasive device by the measurements of pulse transmit time and the distance between 2 recording sites. Results:The mean age was 64.7±7.3 (range, 55 to 79) years the in PEXG group and 63.8±6.6 (range, 51 to 77) years in the control group. There were 8 men (32%) and 17 women (68%) in the PEXG group and 11 men (44%) and 14 women (56%) in the control group. The CF-PWV of the PEX group was significantly higher than that of the control group (P<0.001). Conclusions:We have revealed an association between PEXG and increased CF-PWV. Also, increased CF-PWV may be considered as a risk factor for the development of PEXG.

Effect of axial length on retinal nerve fiber layer thickness in children.

Purpose: To investigate the effect of axial length on peripapillary retinal nerve fiber layer (RNFL) thickness in myopic, hyperopic, and emmetropic eyes in children by Cirrus HD spectral-domain optical coherence tomography (OCT). Methods: Subjects were divided into 3 groups according to their refractive status: myopic (n = 36), emmetropic (n = 30), and hyperopic (n = 28) eyes. The RNFL thickness measurements were taken from the superior, inferior, nasal, and temporal quadrants in the peripapillary region by Cirrus HD OCT. Axial length was also determined for each patient. Results: The myopic eyes had thinner average RNFL and RNFLs of temporal, superior, nasal, and inferior quadrants than the hyperopic eyes (p1<0.001, p2 = 0.004, p3 = 0.011, p4 = 0.006, p5 = 0.033, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of all quadrants had significant negative correlations with axial length. On the other hand, after applying modified Littmann formula for correction of magnification effect, the differences among the 3 groups disappeared (all p>0.05). Conclusions: We have shown that axial length and accordingly refractive status influenced peripapillary RNFL thickness measurements by Cirrus HD OCT in children. Therefore, to make a correct diagnosis of glaucoma or other optic neuropathies in children, either axial length—induced magnification effect should be corrected by ophthalmologists or the current Cirrus HD OCT database should be revised taking axial length into consideration.

Effect of Pterygium Surgery on Tear Osmolarity

Purpose. To investigate changes of dry eye test results in patients who underwent pterygium surgery. Methods. Seventy-four patients who underwent primary pterygium surgery were enrolled in this study. At the baseline, 3-, 12-, and 18-month visits, measurements of tear osmolarity, BUT, and Schirmer test were performed. The patients were divided into 2 groups: Group 1, which consisted of patients in whom pterygium did not recur, and Group 2, which consisted of patients in whom pterygium recurred after surgery. Results. The patients in Group 1 had lower tear osmolarity levels after surgery than those at baseline (all P < 0.001). In Group 2 the tear osmolarity levels did not differ from baseline after 18 months (P = 0.057). The prevalence rates of dry eye syndrome (DES) were lower than that at baseline and 18 months after surgery in Group 1 (P = 0.002). In Group 2, the incidence of DES was lower after 3 months than at baseline (P = 0.03) but was similar to the baseline rate after 12 and 18 months (both P > 0.05). Conclusions. Anormal tear film function associated with pterygium. Pterygium excision improved tear osmolarity and tear film function. However, tear osmolarity deteriorated again with the recurrence of pterygium.

Investigation of tear osmolarity in early rheumatoid arthritis: relation to disease activity

OBJECTIVE To investigate the frequency of dry eye (DE) by measuring tear osmolarity (TO) with the recently introduced TearLab system (TearLab Corp, San Diego, Calif.) in patients with early rheumatoid arthritis (ERA) and the relationship between the severity of DE and ERA disease activity. DESIGN Prospective study PARTICIPANTS Sixty-four eyes of 64 newly diagnosed and untreated patients with ERA were enrolled in this study. METHODS TO measurements, tear break-up time (TBUT), and Schirmer tests were performed. ERA disease activity was evaluated according to the disease activity score 28 (DAS28). The patients were divided into 3 groups according to DAS28 scores as follows: mild (DAS28 ≤ 3.2), moderate (3.2 < DAS28 ≤ 5.1), and severe (DAS28 > 5.1). RESULTS DE was identified in 46 (71.8%) patients with ERA according to the TO values. There were significant differences among these groups concerning TO (p = 0.001) and TBUT (p = 0.005) scores, whereas there was no significant difference between these groups regarding Schirmer scores (p = 0.200). In addition, DAS28 values were positively correlated with TO values (r = 0.710, p < 0.001), negatively correlated with Schirmer scores, (r = -0.251, p = 0.045), and negatively correlated with TBUT scores (r = -0.335, p = 0.007) among all patients. CONCLUSIONS Our study demonstrated a relationship between the ERA disease activity and severity of DE by using TO measurements with the TearLab system. Therefore, TO measurement could be added to other classical DE tests for diagnosing DE and for assessing the degree of disease activity of ERA.

Intravitreal triamcinolone acetonide versus pars plana vitrectomy for pseudophakic cystoid macular edema.

Purpose: To compare the efficacy of intravitreal triamcinolone acetonide injection versus 23-gauge pars plana vitrectomy with internal limiting membrane peeling for the treatment of chronic pseudophakic cystoid macular edema (CME) after uncomplicated cataract surgery. Methods: This retrospective, comparative, consecutive case series study included 39 patients with chronic pseudophakic CME. Twenty eyes in 20 patients were treated with intravitreal triamcinolone acetonide injection (IVT group), and 19 eyes in 19 patients were treated with pars plana vitrectomy with internal limiting membrane peeling (PPV group). In both groups, complete ophthalmologic examinations were performed before and after procedures. Findings were compared between the groups. Results: Both groups experienced a significant improvement in visual acuity and macular thickness after 12 months follow-up. At months 1 and 2, the IVT group showed a significant improvement in visual acuity and a significant reduction in macular thickness compared with the PPV group (p < 0.05), but these differences were not statistically significant between the groups after the 12-month period. Conclusion: Both intravitreal steroid injection and pars plana vitrectomy with internal limiting membrane peeling had a favorable effect on visual and anatomic results in patients with chronic pseudophakic CME. However, surgical treatment had no advantage over intravitreal triamcinolone acetonide injection after 12-months follow-up.

Transepithelial High-Intensity Cross-Linking for the Treatment of Progressive Keratoconus: 2-year Outcomes

ABSTRACT Purpose: To report 2-year outcomes of transepithelial high-intensity cross-linking (CXL) procedure in the treatment of patients with progressive keratoconus. Methods: Forty-eight eyes of 48 consecutive progressive keratoconus patients who underwent transepithelial accelerated CXL procedure were enrolled in the study. Each patient underwent pre- and postoperative comprehensive ophthalmologic examinations including determination of refractive error as spherical equivalent (SE) and corrected distant visual acuity (CDVA), slit lamp biomicroscopic examination, fundoscopy, and a detailed analysis on a Scheimplug+Placido device (Sirius, CSO, Florence, Italy). The riboflavin solution, which was composed of riboflavin 0.25% with hydroxypropyl methylcellulose (HPMC) and benzalkonium chloride (BAC) (ParaCel, Avedro), was used in the procedure. The cornea was exposed to ultraviolet A light (KXL System, Avedro Inc., Waltham, MS, USA) for 2 minutes and 40 seconds at an irradiance of 45 mW/cm2. Results: The mean age of the patients was 25.9 ± 4.0 (ranging from 18 to 33) years. No significant changes were observed in the mean CDVA, SE, and topographic indices at year 1 and year 2 visits compared to preoperative examination. The mean corneal thickness at the thinnest point was significantly higher at year 1 and year 2 visits than at preoperative examination (p1 = 0.014 and p2 = 0.017, respectively). No intra- or postoperative complications or adverse reactions were observed. Conclusions: Transepithelial high-intensity (irradiance of 45 mW/cm2 for 2 minutes and 40 seconds) CXL using 0.25% riboflavin solution was a safe and effective method to halt the progression of keratoconus for a 2-year follow-up period.

The impact of hypertension on retinal nerve fiber layer thickness and its association with carotid intima media thickness

Abstract Objective. Our aim was to investigate retinal nerve fiber layer (RNFL) thickness in hypertensive patients using spectral-domain optical coherence tomography (SD-OCT) and to evaluate the relationship between RNFL thickness and carotid intima media thickness (CIMT). Methods. This study included 59 patients with hypertension (HT) (53.6 ± 10.7 years) and 54 age-matched healthy controls (51.0 ± 8.1 years). We evaluated anthropometric and metabolic parameters as well as RNFL and CIMT measurements in patients with hypertension and controls. Results. The average RNFL thickness was 86.60 ± 10.86 μm in hypertensive patients and 93.63 ± 7.30 μm in healthy controls (p < 0.001). Selective thinning of the RNFL was found in the superior and inferior quadrants. Mean CIMT values were higher in patients with HT (0.80 ± 0.15 mm) than the healthy subjects (0.71 ± 0.1 mm) (p < 0.001). The average, inferior and nasal RNFL thickness were negatively associated with diastolic blood pressure respectively (r = − 0.112, r = − 0.210, r = − 0.225). There was an inverse correlation between RNFL thickness in the average and superior retinal quadrant and CIMT (r = − 0.201, r = − 0.185). There were no correlations between RNFL thickness and age, body mass index, fasting plasma glucose, lipid parameters, high-sensitive C-reactive protein and microalbuminuria. Conclusion. RNFL thickness is reduced in hypertensive patients and may be associated with atherosclerosis.

The relationship between retinal nerve fiber layer thickness and carotid intima media thickness in patients with type 2 diabetes mellitus

AIMS The aim of the present study was to investigate retinal nerve fiber layer (RNFL) thickness in patients with type 2 diabetes mellitus (T2D) using spectral-domain optical coherence tomography and to evaluate the relationship between RNFL thickness and carotid intima media thickness (CIMT). METHODS This study included 171 patients with T2D (53.2 ± 8.8 years) and age matched 61 healthy controls (51.9 ± 8.1 years). We evaluated anthropometric and metabolic parameters as well as RNFL and CIMT measurements in patients with T2D and controls. The Mann-Whitney U test was used to compare the continuous variables and the Chi-square test was used to compare categorical variables. Spearmans rank correlation test was used for calculation of associations between variables. RESULTS The average RNFL thickness was 84.82 ± 11.22 μm in patients with T2D and 92.35 ± 8.45 μm in healthy controls (p<0.001). Mean CIMT values were higher in patients with T2D (0.80 ± 0.1mm) than the healthy subjects (0.72 ± 0.1mm) (p<0.001). A significant negative correlation was found between age and all quadrants of RNFL. There was a negative correlation between average RNFL thickness and HbA1c (r=-0.176), uric acid (r=-0.145), CIMT (r=-0.190) and presence of carotid plaque (r=-0.193). The superior RNFL thickness was negatively associated with HbA1c (r=-0.175), CIMT (r=-0.207) and carotid plaque (r=-0.176). There was also an inverse correlation between the inferior RNFL thickness and HbA1c (r=-0.187) and carotid plaque (r=-0.157). CONCLUSION Thinning of RNFL might be associated with atherosclerosis in patients with T2D.