Hatice Arda

Ocular blood flow in patients with obstructive sleep apnea syndrome (OSAS).

BackgroundSleep-related disorders are among the important risk factors for neurovascular diseases. Obstructive sleep apnea syndrome (OSAS) is characterized by snoring, excessive daytime sleepiness, and insomnia. Our aim was to investigate the presence of glaucoma in patients with OSAS and to reveal vascular pathology related to the pathogenesis of glaucoma in those patients.Patients and methodsThe study included 31 patients with OSAS and 25 control subjects. Orbital Doppler ultrasonography was used to determine the resistivity index (RI) in the ophthalmic artery and central retinal artery. All patients and controls underwent perimetric examination.ResultsThe prevalence of glaucoma in the group of patients with OSAS was 12.9% (4/31); all of these 4 patients with glaucoma were in the “severe” OSAS group. No statistically significant difference was found between ophthalmic artery resistivity index (OARI), central retinal artery resistivity index (CRARI), and intraocular pressure (IOP) between patients and controls (p > 0.05). There was a positive correlation between OARI and mean defect (MD), CRARI and MD, and CRARI and loss variance (LV) values (p < 0.05). There was also a positive correlation between IOP and the apnea-hypopnea index (AHI) (p = 0.001).ConclusionsIn patients with OSAS, a high prevalence was found and it is interesting to note that all of the four glaucoma patients were in the severe OSAS group. The positive correlation observed between IOP and AHI suggests that increased IOP values may reflect the severity of OSAS. The positive correlation between OARI and MD and also between CRARI and MD as well as LV suggests that visual field defects may be due to optic nerve perfusion defects and these field defects also increase as the RI increases.

Obstructive sleep apnoea prevalence in non-arteritic anterior ischaemic optic neuropathy

Aims The aim of this study was to show the prevalence of obstructive sleep apnoea (OSA) in non-arteritic anterior ischaemic optic neuropathy (NAION). Methods 20 patients diagnosed with NAION were included in the study. 20 age and sex matched subjects with similar risk factors for NAION, such as diabetes mellitus (DM) and hypertension (HT), constituted the control group. All cases underwent polysomnography for investigation of the presence of OSA. Cases with an Apnoea–Hypopnoea Index >5 were accepted as having OSA. Results Mean ages of the patients and controls were 60.90±8.14 and 61.15±7.23 years, respectively. There were no significant differences between the patient and control groups in terms of age, gender, body mass index, smoking/alcohol consumption or systemic diseases. In the patient group, 85% were diagnosed with OSA compared with 65% in the control group (p>0.05). Conclusions We found a high prevalence of OSA in patients with NAION but it was also high in the control group (p>0.05). This may be due to the fact that the two groups were matched for the same risk factors for NAION. The study indicates that OSA is not a risk factor for NAION in itself but is the contributing factor as it has effects on the vascular endothelium in DM, HT and atherosclerosis.

The role of advanced oxidation protein products and total thiols in diabetic retinopathy.

Purpose This study aimed to investigate the role of protein peroxidation by detecting the serum levels of advanced oxidation protein products (AOPP), a novel marker for the degree of oxidative damage to proteins, and total thiol as a marker of antioxidant status in diabetic patients with or without diabetic retinopathy (DR) and to compare the results with those of control subjects. Methods The study groups consisted of two separate subgroups: 1) 37 patients (14 male, 23 female) with noninsulin-dependent diabetes mellitus (NIDDM) showing diabetic retinopathy (DR) and 2) 20 patients with NIDDM and without any signs of DR (9 male, 11 female); 26 healthy non-diabetic control subjects (15 male, 11 female) were selected from the patients attending our department for refractive disorders. Venous blood samples of all participants were collected in the morning after an overnight fast, and serum samples stored at −70°C until assay for AOPP, and total thiol. Results AOPP levels were significantly higher in diabetic patients with (210.9±73.0 μmol/L) or without DR (222.7±94.4 μmol/L) when compared to those of controls (152.4±72.04 μmol/L) (p=0.004). Even though the difference was not statistically significant (p=0.095), total thiol levels in cases with DR (278.7±139.1 μmol/L) were lower than those without DR (334.0±129.4 μmol/L) and controls (353.2±145.6 μmol/L). Correlation tests did not reveal any association between these parameters and age, sex, or duration of DM. Conclusions The present study suggests that increased protein oxidation may contribute to the pathogenesis of DR.

Overexpression of vascular endothelial growth factor receptor 2 in pterygia may have a predictive value for a higher postoperative recurrence rate

Background To investigate the expression levels of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 1 (VEGFR-1) and VEGFR-2 in pterygium and to clarify the prognostic significance of these expressions in pterygia. Methods A total of 40 surgically excised pterygia and 9 normal conjunctivae were immunohistochemically studied applying the streptavidin–biotin method in paraffin-embedded tissue sections. Monoclonal antibodies were targeted against VEGF, VEGFR-1 and VEGFR-2 proteins. At the sixth postoperative month, the recurrence rate was graded on a scale of 1–4. Results The mean percentage of VEGF-positive epithelial cells was comparable in pterygium and normal conjunctivae. However, the pterygium group presented higher expression levels of VEGF in pterygia endothelial cells (p=0.05). In terms of VEGFR-1 expression in epithelial cells, no statistically significant difference was found between two groups (p=0.658). However, normal conjunctivae exhibited higher expression levels of VEGFR-1 in endothelial cells (p=0.002). Epithelial cells in pterygium presented higher combined scores of VEGFR-2 (87.5% and 22.2%, respectively) (p=0.013). While higher expression levels of VEGFR-2 were documented in pterygia endothelial cells, no VEGFR-2 immunoreactivity was observed in the endothelial cells of normal conjunctivae (p<0.001). Expression levels of VEGFR-2 in epithelial cells and endothelial cells were positively correlated with the postoperative recurrence grading system (p<0.001 and τ=0.627, p=0.001 and τ=0.508, respectively). Conclusions The results suggest that VEGF may play a key role through VEGFR-2 in the pathogenesis of pterygium. Moreover, overexpression of VEGFR-2 in pterygia may have a predictive value for a higher postoperative recurrence rate.

Evaluation of ocular surface damage and dry eye status in chronic hepatitis C at different stages of hepatic fibrosis.

Purpose: The purpose of this study was to explore changes in ocular surface and tear function parameters in chronic hepatitis C at different stages of hepatic fibrosis. Methods: Fifty-four patients with biopsy-proven chronic hepatitis C and 54 age- and sex-matched healthy control subjects without systemic hepatitis C infection were examined with the Ocular Surface Disease Index questionnaire, Schirmer with and without anesthesia, tear film breakup time, and scoring of ocular surface Lissamine green staining using modified Oxford and van Bijsterveld scoring systems and corneal fluorescein staining. Results: Patients with chronic hepatitis C scored significantly worse than the control subjects on all parameters: modified Oxford scores of Lissamine green staining (5.5/3.0; P <0.001), Oxford and van Bijsterveld scores (4.0/2.0; P <0.001), and corneal fluorescein staining (1.5/0.0; P = 0.001). The chronic hepatitis C group also had higher Ocular Surface Disease Index scores than the control subjects (22.3/13.7; P = 0.001). Schirmer with and without anesthesia and tear film breakup time scores were found to be lower in patients with chronic hepatitis C (P <0.001). Moreover, patients with advanced stages of hepatic fibrosis (stages 4-6) had significantly lower values of tear film breakup time and worse Ocular Surface Disease Index scores and ocular surface vital dye staining than those with initial stages of hepatic fibrosis (stages 0-3). Conclusion: Patients with chronic hepatitis C, especially those with advanced stages of hepatic fibrosis, were more likely to exhibit severe ocular surface damage and signs of dry eye.

Orbital Apex Syndrome in Herpes Zoster Ophthalmicus

Orbital apex syndrome is a rare manifestation of Herpes Zoster Ophthalmicus. Herein we report on a case of orbital apex syndrome secondary to Herpes Zoster Ophthalmicus. A 75 year-old male complained of vision loss, conjunctival hyperemia and proptosis on the left eye, was referred to our clinic. Visual acuity was 5/10 Snellen lines and he had conjunctival hyperemia, chemosis, minimal nuclear cataract and proptosis on the left eye. A diagnosis of orbital pseudotumor was demonstrated firstly. The patient received oral and topical corticosteroids, antiinflammatory and antibiotic agents. On day 2, vesiculopustular lesions were observed, Herpes Zoster Ophthalmicus was diagnosed and corticosteroid treatment stopped, oral acyclovir treatment initiated. Two days later, total ophthalmoplegia, ptosis and significant visual loss were observed on the left. The diagnosis of orbital apex syndrome was considered and the patient commenced on an intravenous acyclovir treatment. After the improvement of acute symptoms, a tapering dose of oral cortisone treatment initiated to accelarate the recovery of ophthalmoplegia. At 5-month follow-up, ptosis and ocular motility showed improvement. VA did not significantly improve because of cataract and choroidal detachment on the left. We conclude that ophthalmoplegia secondary to Herpes Zoster Ophthalmicus responds favourably to intravenous acyclovir and steroids.

Changes in Central Corneal Thickness, Intraocular Pressure, and Oxidation/Antioxidation Parameters at High Altitude

BACKGROUND The authors aimed at investigating ophthalmological changes at high altitude and correlating this with blood oxidation/antioxidation parameters. METHODS There were 40 volunteers who participated in the study. Initial ophthalmological examinations were performed at 3543 ft (1080 m) and repeated on the following day after the participants climbed to an altitude of 9186 ft (2800 m) on Mt. Erciyes, Turkey. Venous blood samples were taken at both altitudes to evaluate total oxidative system (TOS) and antioxidative system (TAS) levels. RESULTS IOP-right eyes at 3543 ft (1080 m) was 13.23 +/- 0.43 mmHg and significantly increased to 14.45 +/- 0.56 mmHg at 9186 ft (2800 m). LOP-left eyes at 3543 ft (1080 m) was 13.50 +/- 0.44 mmHg and increased to 14.13 +/- 0.54 mmHg at 9186 ft (2800 m) (P = n.s.). Central corneal thickness (CCT) of the right eyes was 540.98 +/- 4.34 microm at 3543 ft (1080 m) and significantly increased to 549.73 +/- 4.59 microm at 9186 ft (2800 m). CCT of the left eyes was 542.13 +/- 29.01 microm at 3543 ft (1080 m) and significantly increased to 547.23 +/- 4.59 microm at 9186 ft (2800 m). Spherical equivalent refraction of right or left eyes did not show any significant changes. TOS at 3543 ft (1080 m) was 5.33 +/- 0.76 micromol H2O2 equiv/L and significantly increased to 7.55 +/- 0.82 micromol H2O2 equiv/L at 9186 ft (2800 m). TAS at 3543 ft (1080 m) was 2.45 +/- 0.12 micromol H2O2 equiv/L and decreased to 2.22 +/- 0.08 micromol H2O2 equiv/L (P = n.s.) at 9186 ft (2800 m). There was a positive correlation between TAS and LOP at 9186 ft (2800 m). CONCLUSION Increased CCT can be related to stromal edema caused by hypoxias effect on corneal endothelial function. Although TOS increased at high altitude, TAS did not show any parallel increase. Since this was nonacclimatized climbing, the antioxidant system could not have reached sufficient levels to counterbalance the observed oxidant stress.

Invasive squamous cell carcinoma of the conjunctiva first misdiagnosed as a pterygium: a clinicopathologic case report.

Purpose. To describe the clinical findings of a patient who initially underwent surgery for a pterygium and who was finally diagnosed with invasive squamous cell carcinoma, and to determine the necessity and importance of pathologic investigation in all cases of a presumed pterygium. Methods. A case report. Results. A 63-year-old man was referred for severe pain, redness, and purulent secretion in his right eye. A year earlier, he had undergone excision of a pterygium in his right eye by a bare sclera technique without any adjunctive antimetabolite in a private eye clinic. Furthermore, 6 months after this operation, he had undergone autologous conjunctival graft surgery because of dehiscence of the surgical site. His visual acuity was only light perception in the right eye. Slitlamp biomicroscopy showed severe nasal corneoscleral melting, purulent secretion, conjunctival hyperemia, corneal edema, hypopyon, intracamaral hemorrhage, and lid swelling. Ultrasonography showed a right hypoechoic mass invading the nasal part of the globe and a totally detached retina. Orbital magnetic resonance imaging showed a large (2 cm in diameter), irregular, lobulated mass invading the globe in the medial part of the right orbit. Results of a biopsy were consistent with squamous cell carcinoma. Because of the extensive intraocular involvement at the time of the diagnosis, subtotal orbital exenteration was performed. Conclusions. All pterygia should be evaluated meticulously with regard to possible underlying causes, such as carcinoma in situ or squamous cell carcinoma, and all excised lesions should also be evaluated pathologically to prevent such serious adverse outcomes that are mentioned in this case report.

Multifocal electroretinogram for assessing sun damage following the solar eclipse of 29 March 2006 Multifocal electroretinography in solar maculopathy

AimTo evaluate the clinical findings and multifocal electroretinography results of cases with solar maculopathy due to eclipse watching.Patients and MethodEight eyes of six patients (ages ranged 12–42) who presented to our clinic after the solar eclipse of 29 March 2006 were evaluated in the study. All patients underwent a full ophthalmologic examination and multifocal electroretinography (mfERG).ResultsVisual acuities at the initial examination were between 20/32 and 20/20; and at final examination between 20/25 and 20/20 respectively. Fundoscopic examination disclosed macular pigmentary changes in almost all patients. Fundus Fluorescein Angiography revealed a window defect in six eyes.The initial findings of the mfERG at the first visit showed a decrease in the P1 and N1 amplitudes of the central responses. The following mfERG recordings showed a recovery in central P1 and N1 amplitudes.ConclusionDecrease in P1 and N1 amplitudes of central macular region can be detected by mfERG in patients with solar maculopathy. Follow-up mfERG test results may recover with the increase of visual acuity.

Pattern electroretinographic recordings in eyes with myopia.

Purpose Pattern electroretinography (PERG) is a specific test for the analysis of functions of the central retina. In this study, we investigated the PERG recordings in subjects with myopia. Subjects and Methods This study was performed on 1 eye of 80 subjects with varying degrees of myopia. Four groups were formed according to the refraction values: group 1: between 0.00 and −0.75 diopter (D); group 2: between −1.00 and −3.00 D; group 3: between −3.25 and −6.00 D; and group 4: between −6.25 and −10.00 D. Amplitudes and latencies of transient PERG P50 and N95 waves were recorded in all subjects. Results P50 and N95 wave amplitudes were lower in higher myopes (groups 3 and 4) when compared with lower myopes (groups 1 and 2; P<0.001). The amount of loss in P50 amplitude was 8% in group 2, 16% in group 3, and 36% in group 4 when compared with group 1. The amount of loss in N95 amplitude was 7% in group 2, 21% in group 3, and 43% in group 4 when compared with group 1. Although P50 wave latencies showed no difference between groups, N95 wave latencies were increased in higher myopes. The elongation in N95 wave latency in group 4 was 3.08 ms. Conclusions Increased axial length may contribute to the decrease in PERG amplitudes in our study. PERG recordings must be carefully evaluated when the group in any study that involves myopic subjects.