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Öğe Chandler syndrome manifesting as ectropion uvea following laser in situ keratomileusis(ELSEVIER SCIENCE INC, 2008) Mocan, Mehmet C.; Bozkurt, Banu; Orhan, Mehmet; Irkec, MuratWe report the case of a 30-year-old woman with recent onset of unilateral iris distortion and glaucoma that was noticed following uneventful laser in situ keratomileusis (LASIK). The corneal endothelium in the right eye appeared normal with the slitlamp microscope, and LASIK-related anterior segment ischemia was initially considered in the differential diagnosis. However, in vivo confocal microscopy revealed abnormal endothelial cells, confirming the diagnosis of iridocorneal endothelial syndrome. In patients having refractive corneal procedures, in vivo confocal microscopy is recommended to diagnose preexisting corneal abnormalities that might otherwise remain undetected.Öğe Comparison of visual field test results obtained through Humphrey matrix frequency doubling technology perimetry versus standard automated perimetry in healthy children(WOLTERS KLUWER MEDKNOW PUBLICATIONS, 2013) Kocabeyoglu, Sibel; Uzun, Salih; Mocan, Mehmet Cem; Bozkurt, Banu; Irkec, Murat; Orhan, MehmetAims: The aim of this study was to compare the visual field test results in healthy children obtained via the Humphrey matrix 24-2 threshold program and standard automated perimetry (SAP) using the Swedish interactive threshold algorithm (SITA) -Standard 24-2 test. Materials and Methods: This prospective study included 55 healthy children without ocular or systemic disorders who underwent both SAP and frequency doubling technology (FDT) perimetry visual field testing. Visual field test reliability indices, test duration, global indices (mean deviation [MD], and pattern standard deviation [PSD]) were compared between the 2 tests using the Wilcoxon signed-rank test and paired t-test. The performance of the Humphrey field analyzer (HFA) 24-2 SITA-standard and frequency-doubling technology Matrix 24-2 tests between genders were compared with Mann-Whitney U-test. Results: Fifty-five healthy children with a mean age of 12.2 +/- 1.9 years (range from 8 years to 16 years) were included in this prospective study. The test durations of SAP and FDT were similar (5.2 +/- 0.5 and 5.1 +/- 0.2 min, respectively, P = 0.651). MD and the PSD values obtained via FDT Matrix were significantly higher than those obtained via SAP (P < 0.001), and fixation losses and false negative errors were significantly less with SAP (P < 0.05). A weak positive correlation between the two tests in terms of MD (r = 0.352, P = 0.008) and PSD (r = 0.329, P = 0.014) was observed. Conclusion: Children were able to complete both the visual test algorithms successfully within 6 min. However, SAP testing appears to be associated with less depression of the visual field indices of healthy children. FDT Matrix and SAP should not be used interchangeably in the follow-up of children.Öğe The Effect of Sintering Heating on Mechanical Properties of Brick Clays [Tuğla Killerinde Sinterleme Sıcaklığının Mekanik Özelliklere Etkisi](2002) Demir, I.; Orhan, Mehmet; Erol, A.; Dorum, AtilaSintering process occupies 60-70% of total production costs during the manufacturing of bricks. In this work, specimens were produced at various temperatures in electrical furnace and physical properties such as plasticity, shrinkage, loss of ignition, density and porosity, water absorption and mechanical properties such as freezing resistance, compressive strength, and other mechanical tests were investigated. Specimens were fired at 800°C did not meet standard mechanical properties. On the other hand, specimens were fired at 900°C shoved higher compressive strength and other specimens also met the standard mechanical requirements. As a result, mechanical properties were found to be greatly affected by the firing temperature of brick.Öğe Elevated Tear Interleukin-6 and Interleukin-8 Levels in Patients With Conjunctivochalasis(LIPPINCOTT WILLIAMS & WILKINS, 2009) Erdogan-Poyraz, Ceren; Mocan, Mehmet C.; Bozkurt, Banu; Gariboglu, Semra; Irkec, Murat; Orhan, MehmetPurpose: To determine the interleukin (IL)-6 and IL-8 levels in the tear samples of patients with conjunctivochalasis (CCh) and to correlate the severity of symptoms with tear IL levels. Methods: Fifty-one eves at different stages of CCh and 10 eves of healthy controls were recruited for this prospective Study undertaken at a single university-based hospital. CCh was graded based on the extent of interior lid margin involvement as follows: 1 = single (temporal) location. 2 = 2 locations, and 3 = whole lid. The presence of punctal occlusion and fluorescein clearance patterns were recorded. Enzyme-linked immunosorbent assay was used to determine IL levels. Severity of symptoms was assessed With the Ocular Surface disease index. Results: of the 5 1 study patients (mean age = 63.4 +/- 6.9 years), 16 had grade 1.21 had grade 2. and 14 had grade 3 CCh. Tear IL-6 and IL-8 levels were significantly higher in patients with CCh than in controls (P <= 0.001). Higher IL levels were observed in grades 2 and 3 CCh than in grade 1 CCh and control eyes (P < 0.001). Patients with CCh who also had punctal occlusion and delayed fluorescein clearance results had higher tear IL levels than those who did not (P <= 0.001). Tear IL levels were positively correlated with the clinical severity of CCh as evaluated with the ocular Surface disease index (r = 0.826. P < 0.001 for IL-6 and r = 0.726, P < 0.001 for IL-8). Conclusions: Inflammation may have a role in the pathogenesis of CCh. The clinical severity of CCh parallels the increased tear IL levels. Markers for inflammation are more pronounced in the advanced stages of this disease.Öğe Serum vitamin D deficiency and its association with systemic disease in exfoliation syndrome(SAGE PUBLICATIONS LTD, 2013) Kocabeyoglu, Sibel; Mocan, Mehmet Cem; Irkec, Murat; Pinar, Asli; Bozkurt, Banu; Orhan, MehmetPurpose: To determine the association of serum vitamin D levels with exfoliation syndrome (XFS) and evaluate its impact on co-associated systemic diseases. Methods: Forty patients with XFS and 40 control subjects without XFS were recruited for this study Serum concentrations of 25-hydroxy vitamin D [25(OH) D] were measured by high-performance liquid chromatography Vitamin D deficiency was defined as a serum 25(OH) D concentration of <20 ng/mL. A detailed medical history including hypertension, diabetes mellitus, ischemic heart disease, cerebrovascular stroke, autoimmune disease, and neurologic disorders such as Parkinson disease and Alzheimer disease was recorded. Student t test and chi-square test was used for statistical evaluations. Results: The mean age of patients with XFS and control subjects was 69.6 +/- 8.1 years (range 58-90 years) and 67.1 +/- 6.3 years (range 60-86 years), respectively (p>0.05). Mean 25(OH) D levels did not differ between XFS (19.8 +/- 8.3 ng/mL) and control (19.9 +/- 10.3 ng/mL) groups (p = 0.978). Patients with XFS had higher prevalence of cerebrovascular (p = 0.026) and cardiovascular disease (p = 0.001). There was no association between the systemic disease status and serum vitamin D levels of patients with XFS. Conclusions: Although vitamin D levels were similar between XFS and control subjects, the levels were found to be decreased in both groups. Patients with XFS had a significantly higher prevalence of cerebrovascular and cardiovascular disease as compared to controls independent of their serum 25(OH) D levels. Low vitamin D level does not appear to be linked to XFS in the studied population.Öğe Tane şeklinin hidrometre deney sonuçları üzerindeki etkisi(Selçuk Üniversitesi Teknik Bilimler Meslek Yüksekokulu, 2006) Özer, Mustafa; Orhan, MehmetBu çalışmada, disk şeklindeki tanelerin sıvı içerisindeki çökme hızını veren eşitlikler kullanılarak tane büyüklüğü dağılımları hesaplanmış ve elde edilen sonuçlar standart hidrometre deney sonuçlarıyla karşılaştırılmıştır. Sonuçta, Stokes yasasıyla levhamsı şekle sahip tanelerin çapının olduğundan daha küçük hesaplandığı ortaya konulmuştur. Bununla birlikte, standart hidrometre deneyinin kil yüzdesini gerçekte olduğundan daha fazla hesapladığı da belirlenmiştir.Öğe Trabekülektomi Sonrası Optik Sinir Başı Topografisi ve Retina Sinir Lifi Tabakasında Meydana Gelen Değişikliklerin Değerlendirilmesi(2006) Şahin, Afsun; Bozkurt, Banu; Kerimoğlu, Hürkan; İrkeç, Murat; Orhan, Mehmet; Saraçbaşı, OsmanAmaç: Glokomlu olgularda trabekülektomi sonrası optik sinir başı (OSB) ve retina sinir lifi tabakasında (RSLT) meydana gelen değişikliklerin tarayıcı laser oftalmoskopi ve polarimetre ile değerlendirilmesi. Gereç ve Yöntem: Trabekülektomi yapılan 13 olgunun 16 gözü çalışmaya dahil edildi. Olguların ameliyat öncesi ve ameliyattan sonra 1. 3. ve 6. aylarda OSB topografisi TopSS (Topographic Scanning system), RSLT kalınlığı NFA GDx ile değerlendirildi.Ameliyat öncesi ve sonrası alınan TopSS ve GDx parametreleri eşleştirilmiş t-testi ile karşılaştırıldı ve p0.05 istatistiksel olarak anlamlı kabul edildi. Bulgular: Trabekülektomi sonrası ortalama göz içi basıncı (GİB) 32.568.51 mmHg’dan 1. ayda 14.683.04 mmHg’ya, 3. ayda 13.823.04 mmHg’ya, 6. ayda 15.781.04 mmHg’ya düştü. Cerrahiden sonra ortalama nöroretinal rim kalınlığının belirgin olarak arttığı görüldü (ameliyat öncesi 1.3671.16 mm2; ameliyat sonrası 1. 3. ve 6. aylarda sırasıyla 1.4301.12 mm2, 1.5401.15 mm2, 1.4291.12 mm2) olarak tesbit edildi (p0.05). Ameliyat sonrası c/d oranı, ½ derinlik hacmi, ½ derinlik alanında ise azalma tespit edildi. GDx parametrelerinden hiçbirinde trabekülektomi sonrası belirgin değişiklik izlenmedi (p0,05). Sonuç: Trabekülektomi sonrası GDx parametrelerinde değişiklik izlenmezken TopSS parametrelerinden NRRA ve c/d oranlarında meydana gelen değişiklikler, trabekülektomi’den sonra GİB düşüşü ile birlikte OSB üzerindeki mekanik basının kalkması ve lamina kribrozanın öne doğru yer değiştirmesi ile açıklanabilir.
