Erkin Ogur
Fırat University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Erkin Ogur.
Psychological Medicine | 2007
Murad Atmaca; Hanefi Yildirim; Huseyin Ozdemir; Erkin Ogur; Ertan Tezcan
BACKGROUND No study to date has examined the effects of mood stabilizer alone and the combination of mood stabilizer and atypical antipsychotic, quetiapine, on hippocampal neurochemical markers of bipolar disordered patients concurrently. We therefore undertook a proton magnetic resonance spectroscopy (1H MRS) study of drug-free patients with bipolar disorder (drug-free group), patients undergoing valproate treatment (valproate group), patients administered valproate+quetiapine (valprote+quetiapine group) and healthy controls, focusing on the in vivo neuroanatomy of the hippocampus. METHOD Thirty patients from the Firat University School of Medicine Department of Psychiatry and 10 healthy controls gave written informed consent to participate in the study. The patients and controls underwent proton magnetic resonance spectroscopic imaging (1H MRSI), and measures of N-acetylaspartate (NAA), choline-containing compounds (CHO), and creatine+phosphocreatine (CRE) in hippocampal regions were obtained. RESULTS The drug-free patients had significantly lower NAA/CRE and NAA/CHO ratios compared with the valproate and valproate+quetiapine groups and the healthy controls. The lower NAA/CRE and NAA/CHO ratios remained statistically significant even after covarying for age or whole brain volume compared with the valproate and valproate+quetiapine groups and healthy controls. In post hoc comparisons, a significant difference was found between the valproate+quetiapine group and the valproate group only with regard to NAA/CHO. CONCLUSION Our findings suggest that valproate has a neuroprotective effect. In post hoc comparisons, a significant difference was found between the valproate+quetiapine and the valproate group with regard to NAA/CHO, indicating that the addition of quetiapine further increases the level of NAA and provides an additional neuroprotective effect.
European Journal of Radiology | 2003
Adem Kiris; Salih Ozgocmen; Ercan Kocakoc; Ozge Ardicoglu; Erkin Ogur
OBJECTIVE Ankylosing spondylitis (AS) is a chronic inflammatory disease mainly affecting the axial skeleton and pulmonary involvement is a well known feature of the disease. The aim of this study was to investigate the pulmonary high resolution computed tomography (HRCT) findings of patients with early AS. The relationship between pulmonary function tests (PFT) and HRCT findings was also determined. SUBJECTS AND METHODS Twenty-eight patients with AS (mean age 30.8+/-7.4 and disease duration 7.0+/-2.6) were included in the study. Patients with a disease duration of >10 years or had other pulmonary diseases were excluded. All patients underwent plain chest radiography (posteroanterior and lateral views), thoracic HRCT and PFT. RESULTS All chest radiographs were normal and HRCT revealed abnormalities in 18 patients. The most common abnormalities seen on HRCT were mosaic pattern (ten of 28), subpleural nodule (seven of 28) and parenchymal bands (five of 28). Seven of ten patients with mosaic pattern revealed air trapping areas on end expiratory scans. Twelve patients had abnormal PFT and all had restrictive type of involvement. Ten of these 12 patients had abnormal HRCT and the remaining two patients had normal HRCT. On the other hand, eight patients with normal PFT had abnormalities on HRCT. CONCLUSION Patients with early AS frequently have abnormalities on HRCT, even though they have normal PFT and chest X-ray. Small airway involvement was found as frequent as interstitial lung disease in early AS.
Progress in Neuro-psychopharmacology & Biological Psychiatry | 2006
Murad Atmaca; Hanefi Yildirim; Huseyin Ozdemir; A. Kursad Poyraz; Ertan Tezcan; Erkin Ogur
Based on earlier structural and functional neuroimaging studies, we specifically wanted to assess N-acetylaspartate (NAA), choline-containing compounds (CHO), and creatine+phosphocreatine (CRE) levels in brain hippocampus previously demonstrated to be involved in the pathophysiology of bipolar disorder which have not been evaluated in first-episode patients. Twelve patients meeting DSM-IV criteria for bipolar disorder who consecutively applied to our department and 12 healthy controls were studied. The patients and controls underwent proton magnetic resonance spectroscopy ((1)H MRS), and measures of NAA, CHO, and CRE in hippocampal regions were obtained. ANOVA revealed in the hippocampus a significant effect of diagnosis for NAA/CRE and for NAA/CHO but not for CHO/CRE. Post hoc analysis showed that patients had a significant bilateral reduction of NAA/CRE and of NAA/CHO. No significant correlation was found between hippocampus volume and ratio measures. Correlation analyses exhibited significant correlation between NAA values and the YMRS for both side of the hippocampus, but not any other clinical variables (age, age at onset, and duration of illness). In summary, hippocampal neuronal abnormalities seem to be present at the onset of bipolar I disorder. These data suggest that neuronal abnormalities in hippocampus may be associated with the severity of bipolar I disorder. As these data were obtained in patients in their first-episode (all the patients were manic), they cannot be explained by chronicity of illness or pharmacological treatment.
Journal of Ultrasound in Medicine | 2012
Mehmet Ruhi Onur; Ahmet Kursad Poyraz; Esra Ercin Ucak; Zulkif Bozgeyik; Ibrahim Hanifi Ozercan; Erkin Ogur
This study was designed to determine the utility of semiquantitative strain elastography in differential diagnosis of solid liver masses.
Journal of Magnetic Resonance Imaging | 2012
Ahmet Kursat Poyraz; Mehmet Ruhi Onur; Ercan Kocakoc; Erkin Ogur
To investigate the effect of fat infiltration on the apparent diffusion coefficient (ADC) of liver, and assess the relationship between ADC and hepatic fat fraction (HFF).
Journal of Medical Systems | 2004
Hanefi Yýldýrým; Hasan Baki Altýnsoy; Necaattin Barýpçý; Uçman Ergün; Erkin Ogur; Fırat Hardalaç; İnan Güler
For the classification of left and right Internal Carotid Arteries (ICA) stenosis, Doppler signals have been received from the patients with coroner arteries stenosis by using 6.2–8.4 MHz linear transducer. To be able to classify the data obtained from LICA and RICA in artificial intelligence, MLP and RBF neural networks were used. The number of obstructed veins from the coroner angiography, intimal thickness, and plaque formation from the power Doppler US and resistive index values were used as the input data for the neural networks. Our findings demonstrated that 87.5% correct classification rate was obtained from MLP neural network and 80% correct classification rate was obtained from RBF neural network. MLP neural network has classified more successfully when compared with RBF neural network.
Journal of Magnetic Resonance Imaging | 2012
Mehmet Ruhi Onur; Fatma Öztürk; Cem Aygun; Ahmet Kursad Poyraz; Erkin Ogur
To evaluate the role of the apparent diffusion coefficient (ADC) measurement made using diffusion‐weighted magnetic resonance imaging (DWMRI) in the differential diagnosis of benign and malignant gastric wall thickening.
Journal of Medical Systems | 2004
Uçman Ergün; Necaattin Barýþçý; Ahmet Tevfik Ozan; Selami Serhatlýoðlu; Erkin Ogur; Fırat Hardalaç; İnan Güler
For the classification of Middle Cerebral Artery (MCA) stenosis, Doppler signals have been received from the diabetes and control group by using 2 MHz Transcranial Doppler. After the Fast Fourier Transform (FFT) analyses of the Doppler signals, Power Spectrum Density (PSD) estimations have been made and Multilayer Perceptron (MLP) and Radial Basis Function (RBF) have been dealt to apply to the neural networks. PSD estimations of Doppler signals received from MCA of 104 subjects have been successfully classified by MLP (correct classification = 94.2%) and RBF (correct classification = 88.4%) neural network. As we have seen in the area under ROC curve (AUC), MLP neural network (AUC = 0.934) has classified more successfully when compared with RBF neural network (AUC = 0.873).
Pediatric Cardiology | 2008
Ayse Murat; Hakan Artas; Erdal Yilmaz; Erkin Ogur
Absence of the pericardium can vary from partial to complete absence. Patients with complete absence of the pericardium are either asymptomatic or have nonspecific chest pain, and no treatment is needed. Patients with partial absence of the pericardium are at risk for possible symptomatic herniation of the left atrial appendage or left ventricle, leading to fatal myocardial strangulation. Therefore, it is very important to differentiate partial from complete absence of the pericardium. A 7-year-old girl presented with isolated congenital absence of the pericardium, which generally has a good prognosis. It is a relatively asymptomatic anomaly that usually requires no treatment. Some cases involve complications that require operative treatment. Absence of the pericardium can be precisely defined by computed tomography and magnetic resonance imaging.
The Eurasian Journal of Medicine | 2012
Mehmet Ruhi Onur; Muammer Akyol; Ahmet Kursad Poyraz; Ercan Kocakoc; Erkin Ogur
OBJECTIVE The purpose of our study was to evaluate the utility of the apparent diffusion coefficient (ADC) value measurement in the diagnosis of peritoneal metastases on diffusion weighted magnetic resonance imaging. MATERIALS AND METHODS Diffusion weighted imaging with conventional magnetic resonance imaging sequences was performed on twenty consecutive oncology patients (group I) with peritoneal metastases. The ADC values of the metastases, the peritoneal fat around the metastases (group I) and the peritoneal fat in patients with no malignancy (group II) at b(0-100), b(0-600), and (b 0-1000) s/mm(2) gradients were measured and compared. RESULTS The apparent diffusion coefficient values of three gradients in peritoneal metastases (2.27±0.4; 1.67±0.7 and 1.09±0.4×10(-3) mm(2)/s at b 100, 600 and 1000 gradients, respectively) were significantly lower than the ADC values of the peritoneal fat around metastases (3.07±0.4; 2.07±0.4; 1.33±0.3×10(-3) mm(2)/s at b 100, 600 and 1000 gradients, respectively) (p<0.05). There was no significant difference between the ADC values of peritoneal fat in the patients of group I and group II at the 3 diffusion gradients (p>0.05). CONCLUSION The measurement of ADC values may be used as a complementary diagnostic method in differentiating peritoneal metastases from peritoneal fat on Diffusion Weighted MRI (DWMRI DWMRI).