Metin Ekinci

Optic disc and retinal nerve fiber layer parameters as indicators of neurodegenerative brain changes in patients with obstructive sleep apnea syndrome

PurposeRetina is a unique part of the central nervous system (CNS) for visualizing the processes of axonal and neuronal degeneration. Optical coherence tomography (OCT) allows direct visualization and measurement of retinal nerve fiber layer (RNFL) thickness, macular volume, and optic disc (OD) parameters. One of the disorders associated with atrophy in different brain regions is obstructive sleep apnea syndrome (OSAS). In the present study, we aimed to determine OD and RNFL changes measured by OCT for investigating the progress of neurodegeneration development in OSAS, excluding all the other conditions that can directly affect RNFL thickness and optic nerve parameters.MethodsBoth eyes of 101 patients with OSAS and 20 controls were investigated by OCT. Full-night polysomnography (PSG) and ophthalmologic examination including automated visual field (VF) examination and OCT were performed in all of the patients.ResultsAccording to the OSAS grading, patients were grouped as mild (n = 15), moderate (n = 27), and severe (n = 59). We found significant decrease in RNFL thickness only in the patients with severe OSAS compared with the other groups and decreased macular ganglion cell thickness in the severe OSAS group compared with the control group. VF parameters were significantly worsened in all the OSAS subgroups compared to the control group. We found different data such as normal or increased optic nerve parameters as result of subtle OD edema, which may mask possible peripapillar axonal loss.ConclusionsWe think that evaluation of neurodegeneration in OSAS is not always possible by examining OD and RNFL because there are difficulties due to the confounding issues of cerebral atrophy and OD edema.

Long–Term Comparison of Fibrin Tissue Glue and Vicryl Suture in Conjunctival Autografting for Pterygium Surgery

Abstract Purpose: Pterygium is a common clinical entity that usually causes visual impairment, astigmatism and cosmetic problems. Although many surgical techniques to treat pterygium have been proposed, no single method, with minimal patient complications, has yet been accepted and established. Excision combined with conjunctival autograft is the most often used procedure for the treatment of primary pterygium, and the technique is associated with minimized recurrence rates in patients. The purpose of our study was to compare visual and refractive outcomes, complications, and recurrence rates with the use of fibrin glue versus 8.0 vicryl suture in pterygium surgery performed with conjunctival autograft. Materials and Methods: Our retrospective, comparative study included 106 eyes of 106 patients operated on for primary pterygium, between the years 2011 and 2012, and followed for ≥ 12 months. Patients were divided into 2 treatment groups: Group 1, vicryl suture use (n = 53), and Group 2, fibrin tissue glue (n = 53). Patient follow–up periods were 21.15 ± 5.3 months for Group 1 and 22.06 ± 5.2 months for Group 2. Results: Demographics and preoperative/follow–up clinical characteristics of patients revealed no significant differences between the 2 patient groups. Additionally, no significant differences were found between the patient groups in visual acuity level changes and refractive values. Although the rates of recurrence (7.5% in Group 1 and 1.9% in Group 2; P = 0.36) and graft dehiscence (Group 1, 7.5% compared with Group 2, 3.8%; P = 0.67) were slightly higher for patients in the suture group, differences did not reach significance. Conclusions: Our study results suggest that conjunctival autografting with fibrin glue has favorable visual and refractive results for patients, and is associated with lower complication rates, compared with use of the traditional 8.0 vicryl suturing technique. We suggest that fibrin tissue glue provides adequate adhesion and that graft loss will not be a problem if protective shields are used in patients postoperatively. The appropriate surgery technique should be selected by considering the advantages and disadvantages of each procedure.

Reduction of Conjunctival Fibrosis After Trabeculectomy Using Topical α-Lipoic Acid in Rabbit Eyes

Purpose:To evaluate the efficacy of &agr;-lipoic acid (ALA) in reducing scarring after trabeculectomy. Materials and Methods:Eighteen adult New Zealand white rabbits underwent trabeculectomy. During trabeculectomy, thin sponges were placed between the sclera and Tenon’s capsule for 3 minutes, saline solution, mitomycin-C (MMC) and ALA was applied to the control group (CG) (n=6 eyes), MMC group (MMCG) (n=6 eyes), and ALA group (ALAG) (n=6 eyes), respectively. After surgery, topical saline and ALA was applied for 28 days to the control and ALAGs, respectively. Filtrating bleb patency was evaluated by using 0.1% trepan blue. Hematoxylin and eosin and Masson trichrome staining for toxicity, total cellularity, and collagen organization; &agr;-smooth muscle actin immunohistochemistry staining performed for myofibroblast phenotype identification. Results:Clinical evaluation showed that all 6 blebs (100%) of the CG had failed, whereas there were only 2 failures (33%) in the ALAG and no failures in the MMCG on day 28. Histologic evaluation showed significantly lower inflammatory cell infiltration in the ALAGs and CGs than the MMCG. Toxicity change was more significant in the MMCG than the control and ALAGs. Collagen was better organized in the ALAG than control and MMCGs. In immunohistochemistry evaluation, ALA significantly reduced the population of cells expressing &agr;-smooth muscle action. Conclusions:&Agr;LA prevents and/or reduces fibrosis by inhibition of inflammation pathways, revascularization, and accumulation of extracellular matrix. It can be used as an agent for delaying tissue regeneration and for providing a more functional-permanent fistula.

Occupational Exposure to Lead Decreases Macular, Choroidal, and Retinal Nerve Fiber Layer Thickness in Industrial Battery Workers

Abstract Purpose: To evaluate the toxic effects of chronic lead (Pb) exposure on retinal nerve fiber layer thickness (RNFLT), macular thickness (MT) and choroidal thickness (CT) in battery industry workers. Materials and Methods: Male factory workers (n = 50) and healthy non-employees (n = 20) participated in the study. Group 1 (n = 22) comprised lead workers; Group 2 (n = 16), box makers; Group 3 (n = 12), assistant personnel; and Group 4 (n = 20), healthy non-employees. All participants were given Best-Corrected Visual Acuity (BCVA) tests, full ophthalmologic examinations, and Spectral Domain Optical Coherence Tomography (SD-OCT) of the optic nerve head, RNFL, macula, and choroid. Blood lead levels (BLL) in venous blood samples were determined. The duration of exposure to lead varied, and is expressed in months. Results: Average (mean ± SD) ages of participants were 27.55 ± 4.00, 28.69 ± 3.48, 32.00 ± 3.38, and 29.85 ± 5.48 yrs (Groups 1–4, respectively). BLL were 46.2 ± 2.32, 29.31 ± 3.30, 16.9 ± 1.9, and 2.85 ± 0.98 µg/dL (Groups 1–4, respectively). Durations of exposure to lead were 43.86 ± 10.81, 42.81 ± 4.86, and 49.42 ± 6.14 mo (Groups 1–3, respectively). OCT averages for RNFL were 101.68 ± 5.32, 119.50 ± 13.47, 127.67 ± 8.92, and 130.9 ± 6.63 μm (Groups 1–4, respectively). Although RNFLTs of Group 1 were significantly less than those of for Groups 2–4, and, RNFLTs of Groups 2 and 3 were significantly less than that of Group 4, there were no significant differences between Group 2 and 3. MTs were 94.50 ± 6.78, 105.63 ± 5.43, 111.50 ± 6.74 and 147.95 ± 6.67 μm, (Groups 1–4, respectively). CTs were 176.41 ± 15.39, 222.19 ± 17.79, 239.17 ± 15.64, and 251.50 ± 10.98 μm (Groups 1–4, respectively). Both MTs and CTs displayed significant differences among the four groups. Conclusions: Ocular changes in individuals who are chronically exposed to lead include decrease in RNFT, MT, and CT, and thus these parameters should be evaluated during ophthalmologic examination of individuals working in lead-based industries.

Paintball-related ocular trauma: paintball or painball?

Background The aim of this study is to describe the type and severity of paintball-related ocular trauma and to determine the necessary precautions to minimize the risk of ocular injury regardless of whether adequate eye protection was used. Material/Methods A retrospective chart review identified patients treated for paintball-related ocular trauma at the Ataturk University Medical Hospital from June 2010 through March 2013. A descriptive analysis of data was performed. Results Ten patients with paintball-related ocular trauma were identified. At the time of their first examination, 7 of these patients had visual acuity (VA) of 20/200 or worse. One patient had a final VA of no light perception and 4 patients had a final VA of 20/200 or worse. Hyphema was noted in 7 patients, traumatic cataract in 2, iridodialysis in 2, retinal detachment in 3, and secondary glaucoma in 1. Six patients required surgery. Although all victims have used eye protection during the game, all patients were injured after they thought the game was over and had taken off their helmets or eye-protective devices. Conclusions Paintball-related accidents result in serious ocular trauma and most of the patients require surgery. These injuries result in severe loss of VA in some patients. Uninterrupted use of proper eye protection whenever a player is in the game field, even after they believe the game has ended, may reduce the incidence of severe ocular trauma in paintball players.

Oculogyric crisis in a patient taking metoclopramide

Oculogyric crisis is an acute dystonic reaction of the ocular muscles characterized by bilateral dystonic elevation of visual gaze lasting from seconds to hours. This reaction is most commonly explained as an adverse reaction to drugs such as antiemetics, antipsychotics, antidepressants, antiepileptics, and antimalarials. Although the incidence of metoclopramide-induced acute dystonic reactions has been reported as 25% in children, there have been few published cases on oculogyric crisis in general. It is important to be able to recognize this ocular side effect because, without a thorough patient history, symptoms can be confused with other diseases such as versive seizures, paroxysmal tonic upward gaze, and encephalopathy. In this paper, we report a case of oculogyric crisis induced by metoclopramide.

The Long-Term Follow-Up Results of External Dacryocystorhinostomy Skin Incision Scar with “W Incision”

Abstract Objective: To determine the effect of “W incision” instead of classical vertical incision at external DCR on scar formation. Materials and Methods: Patients with acquired nasolacrimal duct obstruction (NLDO) who were treated with external DCR with classical vertical incision, and patients who were treated with external DCR with “W incision” were included in the study. The first 39 eyes were operated with a vertical incision, and the remaining 37 eyes were operated with a “W incision”. All the skin incision scars of the patients were assessed and scored by at least the 6th month. The assessment was made by both the patients themselves, and by an ophthalmologist other than the surgeon himself, each scored the incision scar separately (single-masked study). Scores for both groups were compared, and statistical analyses were performed. Results: Self-assessment scores for the incision scar were Grade 2.28 ± 0.94 in the Vertical incision group, and Grade 1.68 ± 0.57 in the “W incision” group (p < 0.01). The “W incision” scar formation was significantly less noticable than the Vertical incision scar formation. Similarly, the assessment scores of the ophthalmologist other than the surgeon himself were significantly lower for the “W incision” group than for the Vertical incision group. The mean scar assessment scores were Grade 2.13 ± 0.95 in the Vertical incision group, and Grade 1.57 ± 0.68 in the “W incision” group (p < 0.01). Conclusion: Skin scar tissue was found to be significantly reduced with a “W incision” in external DCR operations.

Measurement of Choroidal Thickness Following Caffeine Intake in Healthy Subjects

Abstract Purpose: The aim of this study is to investigate the effect of 200 mg caffeine on subfoveal choroidal thickness (CT) in the macular area as measured by enhanced depth imaging optical coherence tomography (EDI-OCT) in healthy subjects. Materials and methods: Fifty healthy individuals (study group) and 50 healthy individuals (control group) were enrolled in study. In the study group, participants received a 200 mg caffeine capsule and the control group consisted of subjects who received plasebo capsule. The subfoveal CT was measured by EDI-OCT before the caffeine intake and at 30 min, 1 h, 2 h, 3 h, 4 h and 6 h following caffeine intake. Results: SFCT after caffeine intake was significantly decreased at 30 min, 1 h, 2 h, 3 h and 4 h compared to the baseline measurement, while the difference between baseline and 6 h was not statistically significant in the study group. There were no significant differences between the baseline and the other measurement times in the control group (p > 0.05). Conclusion: The thinning of CT begins about 30 min after the oral ingestion of 200 mg of caffeine and lasts for about four hours.

The Ocular Endothelin System: A Novel Target for the Treatment of Endotoxin-Induced Uveitis With Bosentan

PURPOSE We compared the anti-inflammatory effects of bosentan and dexamethasone in endotoxin-induced uveitis (EIU). METHODS Endotoxin-induced uveitis was induced by subcutaneous injection of lipopolysaccharide (LPS, 200 μg) in Wistar rats. Rats were divided randomly into 10 groups (n = 6). Bosentan at doses of 50 and 100 mg/kg were administered orally 1 hour before and 12 hours after LPS injection, and dexamethasone was administered by intraperitoneally 30 minutes before and 30 minutes after LPS injection at a dose of 1 mg/kg. Data were collected at two time points for each control and treatment; animals were killed at either 3 or 24 hours after LPS injection. Histopathologic evaluation and aqueous humour measurements of TNF-α level were performed, and endothelin-1 (ET-1), inducible nitric oxide synthase (iNOS), and endothelin receptor A and B (EDNRA and B) expression were analyzed. RESULTS The group treated with 100 mg/kg bosentan at 24 hours displayed significantly milder uveitis and fewer inflammatory cells compared to LPS-injected animals, and there were similar findings in the dexamethasone-treated group at 24 hours. The TNF-α levels in the dexamethasone treatment group were lower than those in the LPS-induced uveitis control group (P < 0.05); however, there was no difference between the dexamethasone and bosentan treatment groups at 3 and 24 hours after LPS administration. Bosentan treatment at doses of 50 and 100 mg/kg significantly decreased iNOS expression compared to LPS-injected animals (P < 0.001). The ET-1 expression was suppressed significantly by bosentan and dexamethasone at 3 and 24 hours after LPS administration (P < 0.001). The EDNRA expression in the bosentan treatment groups was statistically significantly lower than that in the LPS-induced uveitis control group at 3 and 24 hours after LPS administration (P < 0.05). CONCLUSIONS Bosentan reduces intraocular inflammation and has similar effects as dexamethasone in a rat model of EIU.

evaluation of cardiovascular biomarkers in patients with age-related wet macular degeneration

Aim To evaluate levels of homocysteine, asymmetric dimethylarginine (ADMA), and nitric oxide (NO), as well as activity of endothelial NO synthase (eNOS), in patients with age-related macular degeneration (AMD). Methods The levels of homocysteine, ADMA, and NO and activity of eNOS in patients who were diagnosed with wet AMD by fundus fluorescein angiography (n=30) were compared to a control group with no retinal pathology (n=30). Results Levels of homocysteine and ADMA were found to be significantly higher in the wet AMD group than in the control group (P<0.001), whereas NO levels and eNOS activity were higher in the control group (P<0.001). In the wet AMD group, we detected a 2.64- and 0.33-fold increase in the levels of ADMA and homocysteine, respectively, and a 0.49- and 2.41-fold decrease in the eNOS activity and NO level, respectively. Conclusion Elevated levels of homocysteine and ADMA were observed in patients with wet AMD. Increased ADMA may be responsible for the diminished eNOS activity found in these patients, which in turn contributes to the decrease in NO levels, which likely plays a role in the pathogenesis of AMD.