Penpe Gul Firat

Evaluation of peripapillary retinal nerve fiber layer, macula and ganglion cell thickness in amblyopia using spectral optical coherence tomography

AIMnTo investigate peripapillary retinal nerve fiber layer (RNFL), macula and ganglion cell layer thicknesses (GCC) in amblyopic eyes with spectral domain optical coherence tomography (SD-OCT).nnnMETHODSnThirty six patients with a history of unilateral amblyopia and thirty two children who had emmetropia without amblyopia were included in this study. In this institutional study, 36 eyes of 36 patients with amblyopia (AE), 36 fellow eyes without amblyopia (FE), and 32 eyes of 32 normal subjects (NE) were included. RNFL, GCC and macular thickness measurements were performed with RS-3000 OCT Retina Scan (Nidek Inc CA. USA).nnnRESULTSnThe mean global thicknesses of the RNFL were 113.22±21.47, 111.57±18.25, 109.96±11.31µm in the AE, FE, and NE, respectively. There was no statistically significant difference for mean global RNFL thickness among the eyes (P=0.13). The mean thicknesses of the macula were 258.25±18.31, 258.75±19.54, 248.62±10.57µm in the AE, FE and NE, respectively. There was no statistically significant difference for thickness of macula among the eyes (P=0.06). The GCC was investigated into two parts: superior and inferior. The mean thicknesses of superior GCC were 102.57±13.32, 103.32±10.64, 100.52±5.88µm in the AE, FE, and NE, respectively. The mean thicknesses of inferior GCC were 103.82±12.60, 107.82±12.33, 105.86±10.79µm in the AE, FE and NE, respectively. There was no statistically significant difference for thickness of superior and inferior GCC between the eyes (P=0.63, P=0.46).nnnCONCLUSIONnThe macular thicknesses of AE and FE were greater than the NE, although it was not statistically significant. Amblyopia does not seem to have a profound effect on the RNFL, macula and GCC.

Comparison of ganglion cell and retinal nerve fiber layer thickness in primary open-angle glaucoma and normal tension glaucoma with spectral-domain OCT

BackgroundThe aim of this study was to evaluate the macular thickness (MT), ganglion cell complex (GCC), and circum-papillary retinal nerve fiber layer (RNFL) thickness in primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) with spectral domain optical coherence tomography (SD-OCT).MethodsA total of 169 subjects were enrolled: 52 normal subjects, 61 with POAG, and 56 with NTG. Spectral-domain optical coherence tomography (SD-OCT) was used to analyze MT, GCC, and RNFL thickness. To compare the discrimination capabilities between the MT, GCC, and RNFL thickness measurements, we analyzed the areas under the receiver operating characteristic (ROC) curves (AUCs). The relationships between GCC and RNFL measurement and also the relationships of the groups, with age, gender, GCC, and RNFL thickness were assessed.ResultsNormal subjects showed the thickest superior and inferior GCC, followed by in order NTG and POAG (pu2009<u20090.05). While there was a statistically difference in MT value of the normal subjects and the glaucoma patients (pu2009<u20090.05), MT value did not differ between POAG and NTG (pu2009<u20090.05). RNFL thickness parameters were significantly greater in normal subjects, followed in order by the NTG, and POAG (pu2009<u20090.05). Between the normal and entire glaucoma groups, all GCC and RNFL parameters showed the similar discrimination power. RNFL thickness parameters correlated significantly with all GCC thickness (pu2009<u20090.05). Superior RNFL thickness was the only independent variable between the POAG and NTG patients (odds ratio (OR) 0.942, pu2009=u20090.004, 95xa0%CI 0.905–0.981).ConclusionsSD-OCT evaluation results suggest higher GCC and RNFL parameters for NTG than POAG.

Effects of third generation mobile phone-emitted electromagnetic radiation on oxidative stress parameters in eye tissue and blood of rats

Purpose: To investigate the effects of electromagnetic radiation (EMR) emitted by a third generation (3G) mobile phone on the antioxidant and oxidative stress parameters in eye tissue and blood of rats. Methods: Eighteen Wistar albino rats were randomly assigned into two groups: Group I (n = 9) received a standardized a daily dose of 3G mobile phone EMR for 20 days, and Group II served as the control group (n = 9), receiving no exposure to EMR. Glutathione peroxidase (GSH-Px) and catalase (CAT) levels were measured in eye tissues; in addition, malondialdehyde (MDA) and reduced GSH levels were measured in blood. Results: There was no significant difference between groups in GSH-Px (p = 0.99) and CAT (p = 0.18) activity in eye tissue. There was no significant difference between groups in MDA (p = 0.69) and GSH levels (p = 0.83) in blood. Conclusions: The results of this study suggest that under a short period of exposure, 3G mobile phone radiation does not lead to harmful effects on eye tissue and blood in rats.

Evaluation of metabolite changes in visual cortex in diabetic retinopathy by MR-Spectroscopy

PURPOSEnTo evaluate metabolite changes in the visual cortex of diabetic patients with nonproliferative or proliferative diabetic retinopathy by Magnetic Resonance Spectroscopy (MRS).nnnMATERIALS AND METHODSn15 normal subjects (group 1), 15 patients with diabetes who did not have diabetic retinopathy (group 2), 15 patients with nonproliferative diabetic retinopathy (NPDR) (group 3), and 15 patients with proliferative diabetic retinopathy (PDR) (group 4) were included in the study. Furthermore, diabetic patients were divided into two groups according to HbA1c levels (Group A: 20 patients, HbA1c <8%; Group B: 20 patients, HbA1c >8%). In all cases left visual cortex, amounts of N-acetyl-aspartate (NAA), choline (Cho), and creatine (Cr) were measured by MRS. NAA/Cr, Cho/Cr, and NAA/Cho ratios were calculated. Furthermore, all cases complete blood count (CBC) and biochemical parameters were evaluated.nnnRESULTSnThere was no statistically significant difference for NAA/Cr, Cho/Cr, and NAA/Cho ratios between groups 1, 2, 3, and 4 (P>0.05). However there was a statistically significant difference for NAA/Cr and NAA/Cho ratios between groups A and B (P<0.05). There was no statistically significant difference for Cho/Cr ratio between groups A and B (P>0.05).nnnCONCLUSIONnAlthough NAA/Cr and NAA/Cho ratios decrease in the visual cortex while diabetic retinopathy progresses, these decreases are not statistically significant. While HbA1c levels increase, the NAA concentration decreases in the visual cortex which indicates neuronal loss. The metabolite changes in the visual cortex are associated with acute events rather than chronic.

Evaluation of Pentacam-Scheimpflug imaging of anterior segment parameters in patients with pseudoexfoliation syndrome and pseudoexfoliative glaucoma.

Background:u2002 The aim was to evaluate anterior segment parameters in patients with pseudoexfoliation syndrome (PXS) or pseudoexfoliative glaucoma (PXG) with the Pentacam‐Scheimpflug imaging system.

Influence of corneal parameters in keratoconus on IOP readings obtained with different tonometers

Accurate intraocular pressure (IOP) measurement is important but of unsure reliability in patients with keratoconus. Different types and models of tonometers are available. This study investigated the influence of corneal parameters on IOP readings obtained by a Goldmann applanation tonometer, a non‐contact tonometer and a dynamic contour tonometer.

The effect of apricots on the experimental cataract model formed by sodium selenite.

This study was designed in order to investigate whether sun dried apricots have a preventive effect on the experimental cataract model formed by sodium selenite in rats. Fifty-nine Spraque-Dawley rat pups were divided into three groups. Group 1 (control group) consisted of twenty rat pups, born from the rats nourished ad libitum. Group 2 consisted of 18 newborn rats, born from the rats nourished ad libitum with 10% sun dried natural apricots. Group 3 consisted of 21 newborn rats, born from the rats nourished ad libitum. Subcutaneous (30nmol/gr) sodium selenite injection was applied to all the newborn rats except the control group (Group 1) on postpartum day 10. Cataract development was graded by slit-lamp examination and photography. Encapsulated lenses were analyzed for reduced glutathione (GSH) and malondialdehyde (MDA), a marker of lipid per oxidation. Lenses were also analyzed for total nitrite (TN). The presence of oxidative stress in selenite cataract development and its prevention by sun dried apricots.

Modified Temporary Eyelid Margin Suture for Correction of Congenital Horizontal Tarsal Kink: A Novel Surgical Technique

Purpose: Tarsal kink is a rare congenital eyelid anomaly that may lead to corneal opacity and amblyopia secondary to severe entropion. The authors aimed to describe a modified temporary lid margin suture method for tarsal kink correction. Method: In this novel surgical technique, a double-armed 6/0 prolene suture was passed through the upper eyelid and the lower eyelid margins to correct the tarsal kink under topical anesthesia. Result: The authors found that this procedure was very effective and successful for correction of tarsal kink with no incision of the tarsus or eyelid skin, providing a low risk of amblyopia. Conclusion: The modified temporal lid margin suture is a simple, practical, and effective procedure for tarsal kink correction.

Evaluation of the effects of resveratrol and bevacizumab on experimental corneal alkali burn

PURPOSEnTo evaluate the effects of resveratrol and bevacizumab on experimental corneal neovascularization.nnnMETHODnA corneal alkali burn was performed in 62 eyes of 31 male white Vienna rabbits. Resveratrol (group 1), dimethyl sulfoxide (group 2), bevacizumab (group 3) and 0.9% NaCl (group 4) were administered to both eyes of the rabbits by subconjunctival injection for 7 days. Corneal photos were taken at 15 days after alkali injury. Inflammatory index scores and neovascularization areas were calculated.nnnRESULTSnIn bevacizumab group both inflammatory index scores and the calculation of the corneal neovascularization area was significantly less than the groups.nnnCONCLUSIONnThe subconjunctival administration of bevacizumab inhibits corneal neovascularization effectively in the rabbit corneal alkali burn model. No effect of resveratrol to the corneal neovascularization on experimental model of the corneal alkali burn was seen at the doses of usage.

Short-term effect of topical brinzolamide-timolol fixed combination on ocular surface of glaucoma patients.

AIMnTo evaluate the short-term effect of the fixed combination of brinzolamide-timolol on the ocular surface in glaucoma patients.nnnMETHODSnThis is a prospective study of 23 eyes of 23 patients with newly diagnosed glaucoma. Schirmer I test, tear break-up time (BUT) measurement, conjunctival impression cytology and central corneal thickness (CCT) measurements were performed in one of the eyes of each patients before and 4 weeks after brinzolamide-timolol fixed combination therapy. All patients were asked to answer the OSDI questionnaire form about the ocular surface symptoms at baseline and at 1 week and 4 weeks follow-up visits.nnnRESULTSnAfter brinzolamide-timolol fixed combination theraphy Schirmer I, BUT and CCT values decreased but the only statistically significant decrease was seen in BUT test (P=0.03). OSDI scores increased during the follow-up but this increase was not statistically significant (P=0.22, P=0.42 respectively). Impression cytology findings ranged from 0.78±0.42 to 0.95±0.36 according to the Nelson classification. There was no statistically significant difference between baseline and 4 weeks follow up in impression cytology grades (P=0.15).nnnCONCLUSIONnThe results of our study indicate that short-term use of brinzolamide-timolol fixed combination theraphy does not have a profound effect on ocular surface except BUT values.