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Öğe Brain Perfusion MRI Findings in Patients with Behcet's Disease(Hindawi Publishing Corporation, 2012) Alkan, Alpay; Goktan, Asli; Karincaoglu, Yelda; Kamisli, Suat; Dogan, Metin; Oztanir, Namik; Turan, NergizObjective. To search brain perfusion MRI (pMRI) changes in Behcet's disease (BD) with or without neurological involvement. Materials and Method. The pMRI were performed in 34 patients with BD and 16 healthy controls. Based on neurologic examination and post-contrast MRI, 12 patients were classified as Neuro-Behcet (group 1, NBD) and 22 patients as BD without neurological involvement (group 2). Mean transit time (MTT), time to peak (TTP), relative cerebral blood volume (rCBV), and relative cerebral blood flow (rCBF) were obtained and compared to those of healthy control group (group 3). Results. There was a significant difference in the MTT and rCBF within the pons and parietal cortex in groups 1 and 2. rCBV increased in cerebral pedicle in group 1 compared with groups 2 and 3. In the temporal lobe white matter, prolonged MTT and decreased rCBF were found in groups 1 and 2. In the corpus striatum, internal capsule, and periventricular white matter, rCBF increased in group 1 compared with group 3 and decreased in groups 1 and 2. Conclusion. Brain pMRI is a very sensitive method to detect brain involvement in patients with BD and aids the clinical diagnosis of NBD, especially in patients with negative MRI findings.Öğe Can diffusion weighted magnetic resonance imaging (DW-MRI) be an alternative to 18f-FDG PET/CT (18f fluorodeoxyglucose positron emission tomography) in nasopharyngeal cancers?(Scientific Publishers India, 2017) Yildirim, Ismail Okan; Ekici, Kemal; Dogan, Metin; Temelli, Oztun; Kekilli, Ersoy; Saglik, Semih; Erbay, FatihObjective: This study aimed to evaluate correlations, if any, between the ADC (Apparent Diffusion Coefficient) measurements in MRI (Magnetic Resonance Imaging) and SUV max (Standardized Uptake Value) in F-18-FDG PET/CT in patients with nasopharyngeal cancers and to investigate whether DW-MRI (Diffusion Weighted MRI) can be an alternative to F-18-FDG PET/CT in the evaluation of the response to treatment and prognosis in those patients. Methods: This study was performed between January 2015 and February 2016 at Inonu University Medical Faculty, Department of Radiology on 22 patients who were diagnosed with nasopharyngeal cancer by histopathological evaluation at Department of Pathology of the same faculty. Diffusion weighted images were obtained using 1.5 T MRI in all patients. F-18-FDG PET/CT images were obtained approximately 1-2 weeks after the diffusion-weighted images. Results: Two groups were created according to the histological subtypes as keratinized (n: 8) and non-keratinized (n: 14) among the 22 cases with a definitive histopathological diagnosis of nasopharyngeal cancer. No statistical difference was found between the groups in terms of SUVmax, SUVmean and ADC mean values (p> 0.05). ADC mean values measured in patients with nasopharyngeal cancer were statistically significantly and negatively correlated with SUV max (r=-0.619, p< 0.001) and SUV mean values (r=-0.677, p< 0.001). Conclusion: Even though there are anatomic and patient-related limitations of the DW-MRI in nasopharyngeal cancers, we suggest that it may be a complementary and alternative method of F-18-FDG PET/CT in the evaluation of treatment response and prognosis detection in nasopharyngeal cancers.Öğe Comparison of brain apparent diffusion coefficient value in naturally and assisted conceived newborns(Taylor & Francis Ltd, 2012) Aslan, Mehmet; Dogan, Metin; Celik, Onder; Karsavuran, Nazan; Dogan, Derya Gumus; Botan, Edin; Alkan, AlpayBackground: Our aim was to assess the value of brain apparent diffusion coefficient (ADC) in Intra Cytoplasmic Sperm Injection (ICSI) and spontaneously conceived preterm singletons. Methods: Twenty ICSI-conceived preterm singletons and 20 gestational age matched spontaneously conceived preterm singletons were studied. All subjects underwent diffusion-weighted imaging (DWI). The main outcome measure was the brain ADC value in the in ICSI-conceived and naturally conceived newborns. Results: Children born after ICSI had an increased ADC value than the controls. The ADC values of ICSI-conceived singletons were higher than those of spontaneously conceived singletons at cerebellum, corpus striatum, frontal lobe, occipital lobe, and temporal lobe white matter. The mean Apgar score, birth weight, height, and head circumference of ICSI children were found to be similar to naturally conceived children. Conclusions: Measuring ADC value may be a promising marker in identifying neurological outcome of ICSI-conceived newborns.Öğe Comparison of the effects of PRP and hyaluronic acid in promoting peripheral nerve regeneration An experimental study with vascular conduit model in rats'(Edizioni Luigi Pozzi, 2016) Firat, Cemal; Aytekin, Ahmet Hamdi; Durak, Mehmet Akif; Geyik, Yilmaz; Erbatur, Serkan; Dogan, Metin; Elmas, OmerAIM: Peripheral nerve defects generally occur due to mechanical, chemical, thermal and pathologic causes and the reconstruction is still a challenging problem. In the present study, we aimed to compare the effects of platelet rich plasma (PRP) that has high levels of growth factors and hyaluronic acid (HA) that is known to have positive effects on nerve regeneration by decreasing scar formation in a rat model where they were injected through allogeneic aorta graft in peripheral nerve defects using histopathologic and functional methods. MATERIAL AND METHODS: The study involved 20 Wistar Albino male rats that weighed 200 to 250 grams and aged about 1 year old. Of the rats, two were used as donor for PRP and aorta graft harvest. Three random groups of 6 rats were composed. In all of the groups, the left sciatic nerves were used and 1 cm of defects were created. The right sciatic nerves were used as control groups. Group I was the group repaired with autograft, Group 2 was the group repaired with HA injected through aorta graft and Group 3 was the group repaired with PRP injected through aorta graft. The findings were evaluated in terms of functional (electromyography and walk test analysis) and histopathologic parameters at 12 weeks. RESULTS: In all of the groups varying degrees of axonal regeneration was observed. Group I was the closest group to the control group showing highest rate of nerve regeneration followed by Group 3 where PRP was injected through aorta graft and group 2 where ha was used respectively. CONCLUSION: The study demonstrates that PRP enhances peripheral nerve regeneration more than HA when used in a vascular conduit model.Öğe Congenital Agenesis of Right Internal Carotid Artery: A Report of Two Cases(Ubiquity Press Ltd, 2016) Kahraman, Aysegul Sagir; Kahraman, Bayram; Ozdemir, Zeynep Maras; Dogan, Metin; Kaya, Mehmet; Gormeli, Cemile Ayse; Durak, Mehmet AkifCongenital unilateral agenesis of the internal carotid artery (ICA) is a rare anomaly. Due to proper sufficient collateral circulation via the circle of Willis most cases are asymptomatic, but patients can also present with ischemic or hemorrhagic cerebrovascular insults. The absence of the bony carotid canal is essential to differentiate this anomaly from chronic ICA occlusion. Awareness of this situation by clinicians and radiologists is essential because these patients have an increased incidence of various intracranial pathologies. We report two cases of this rare developmental congenital abnormality occurring in two young patients and describe the presentation, diagnosis, determined developmental causes, imaging findings, and complications.Öğe Detecting the Shape Differences of the Corpus Callosum in Behcet's Disease by Statistical Shape Analysis(Wiley, 2011) Colak, Cemil; Ercan, Ilker; Dogan, Metin; Ozdemir, Senem Turan; Sener, Serpil; Alkan, AlpayThe aim of this study was to assess the shape differences of the corpus callosum (CC) in patients with Behcet's disease using statistical shape analysis (SSA). Additionally, an attempt was made to investigate the changes in CC size according to disease duration. Twenty-five adults with clinically diagnosed Behcet's disease and 25 age-and gender-matched controls were examined by high-resolution structural magnetic resonance imaging. The data obtained from the coordinate of landmarks were analyzed with Euclidean distance matrix analysis and a thin-plate spline analysis. SSA and growth curve models were performed to investigate group differences and to fit the curves. A significant difference was determined between CC shape of Behcet patients and controls (P = 0.006). Based on the analysis, a decrease occurred in the CC size of the Behcet patients as the duration of disease increased. Maximum deformations were determined in the landmarks of interior notch of the splenium, inferior tip of the splenium, posterior-most point of the CC, and topmost point of the CC. Similarly, the landmark of anterior-most point of the CC was identified as having the minimum deformation. Behcet patients had significantly different CC shapes from control subjects. The results suggest that SSA is a promising tool for distinguishing Behcet patients from normal subjects, and that it can give useful information to assist clinicians. Additionally, SSA might be applied to detect shape differences in anatomical structures that are affected by a broad range of neurological diseases. Anat Rec, 294: 870-874, 2011. (C) 2011 Wiley-Liss, Inc.Öğe Diagnostic accuracy of cascade stomach by upper gastrointestinal endoscopy in patients with obscure symptoms: A multi-center prospective trial(Elsevier Masson, 2011) Gulsen, Murat Taner; Koruk, Irfan; Dogan, Metin; Beyazit, YavuzAim: Cascade stomach (CS) is a deformity of stomach, capable of leading dyspepsia, and its actual incidence is unknown. We investigated its frequency and performed a preliminary study to determine endoscopic diagnostic criteria. Material and methods: One thousand four hundred and seventy-five consecutive patients were enrolled to this study. A criteria for CS in endoscopy was defined as follow: A fundal pouch after cardia, difficulty in passage from fundus to corpus and/or requiring a manoeuvre, an angulation separating fundus-corpus. Cases having all three criteria were considered as complete CS (CCS) only the third one as borderline CS (BCS). Results: CS was diagnosed endoscopically in 33 (2.5%) and radiologically in 32 (2.4%) of patients with dyspepsia. Among endoscopically diagnosed CS patients, CCS was found to be present in 17 and BCS was found to be in 16 patients. Patients in whom CS was diagnosed endoscopically, radiological examination revealed CCS in 18 patients, BCS in 14 patients, and 1 patient with normal findings were detected. There were no significant differences between these two groups (P = 0.559). Conclusion: CS can be presented with various upper abdominal symptoms, and it can easily be diagnosed when endoscopic criteria are considered. (C) 2011 Elsevier Masson SAS. All rights reserved.Öğe Diffusion-weighted imaging (DWI) of the liver in assessing chronic liver disease: effects of the presence and the degree of ascites on ADC values(Springer, 2016) Kahraman, Aysegul Sagir; Kahraman, Bayram; Ozdemir, Zeynep Maras; Gormeli, Cemile Ayse; Ozdemir, Fatih; Dogan, MetinPurpose: The aim of this study was to determine the correlation between the liver and spleen apparent diffusion coefficient (ADC) values of patients with chronic liver disease and the presence and the degree of ascites. Materials and method: In this retrospective study, we assessed 107 patients with chronic liver disease and 39 control subjects who underwent upper abdominal MR imaging including echo-planar diffusion-weighted imaging (DWI). Among the 107 cirrhotic patients, 56 were classified as group 1, 25 as group 2, and 26 as group 3 according to the absence, the presence of minimal, and the presence of massive ascites, respectively. The scores of model for end-stage liver disease (MELD) were matched between groups as the standard reference. The liver ADC, spleen ADC, and normalized liver ADC values were compared between the control group and patients' groups. Results: Patients with massive ascites had significantly higher MELD score compared with the other groups. The MELD score was also significantly higher in patient groups than in control group. The liver and normalized liver ADCs of patients' groups were significantly lower than that of the control group. With some overlap among groups, the measured ADC values decreased as the amount of the ascites increased, and these relationships were statistically significant. Furthermore, compared to control group, patients with massive ascites had significantly higher spleen ADCs. Conclusion: Our results indicate that the ADC value of the liver and spleen correlates with the presence and the degree of ascites in patients with chronic liver disease, and merits further study.Öğe Effects of contrast material on the metabolite ratios in single-voxel MR Spectroscopy of intraaxial brain tumors(Churchill Livingstone, 2012) Alkan, Alpay; Burulday, Veysel; Oztanir, Namik; Dogan, Metin; Erbay, Mehmet Fatih; Kocak, Ayhan; Aralasmak, AyseAim: The purpose of our study was to determine whether the administration of contrast material affects the results of MR Spectroscopy (MRS) in different intraaxial brain tumors. Materials and methods: Thirty-three patients (median range 46.72 +/- 2.95, range 9-77) with intraaxial brain tumors underwent MRS before and 5 min after intravenous administration of gadolinium based contrast material at the standard dose of 0.1 mmol/kg (Gadodiamide or Gd-DOTA). Metabolite ratios (N-acetyl aspartate (NAA)/Creatine (Cr), Choline (Cho)/Cr. and NAA/Cho) were calculated. Results: There was no significant difference between the pre and postcontrast MRS spectra as regards to NAA/Cr (p:0.4), Cho/Cr (p:0.2), and NAA/Cho (p:0.2) ratios obtained from the intraaxial brain tumors. Conclusion: Contrast material administration did not change the metabolite ratios of MRS. Contrast administration would be useful in guiding voxel localization in MRS evaluation of intraaxial brain tumors. (C) 2012 Elsevier Ltd. All rights reserved.Öğe Evaluation of metabolite changes in visual cortex in diabetic retinopathy by MR-Spectroscopy(Elsevier Science Inc, 2012) Ozsoy, Ercan; Doganay, Selim; Dogan, Metin; Alkan, Alpay; Firat, Penpe GulPurpose: To evaluate metabolite changes in the visual cortex of diabetic patients with nonproliferative or proliferative diabetic retinopathy by Magnetic Resonance Spectroscopy (MRS). Materials and Methods: 15 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. Results: There 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). Conclusion: Although 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. (c) 2012 Elsevier Inc. All rights reserved.Öğe Evaluation of Vertebral Artery Involvement by Doppler Sonography in Patients With Behcet Disease(Wiley, 2014) Tasolar, Sevgi; Dogan, Metin; Tasolar, Hakan; Kahraman, Aysegul; Kamisli, Suat; Dogan, Adil; Yildirim, OkanObjectives-Neurologic lesions in Behcet disease are most frequently observed in areas supplied by the vertebrobasilar system. We aimed to evaluate possible vertebral artery involvement by Doppler sonography in patients with Behcet disease. Methods-Forty-five patients with Behcet disease and 29 healthy volunteers had Doppler sonography of the vertebral arteries. Patients were grouped according to neurologic examination and magnetic resonance imaging findings as follows: group 1, Behcet disease without neurologic involvement; group 2, neuro-Behcet disease; and group 3, control. Results were assessed with a 95% confidence interval. Results-The main findings of our study were as follows: (1) total vertebral artery volume flow was significantly lower in the patient groups than the control group (P < .05); (2) total volume flow was lower in group 2 than group 1, although the difference was not statistically significant; (3) peak systolic and end-diastolic velocity values were significantly lower in the patient groups than the control group; (4) right and left mean volume values were lower in group 2; and (5) resistive and pulsatility index values for the left vertebral artery were significantly higher in group 2, but no statistically significant differences were found in the resistive and pulsatility index values for the right vertebral artery. Conclusions-Doppler sonography of the vertebral arteries in Behcet disease shows alterations that may aid in the diagnosis and treatment of this condition.Öğe The Evaluation of Vertebrobasilar Artery System in Neuro-Behcet and Behcet Disease using Magnetic Resonance Angiography(Wiley, 2014) Kose, Evren; Kamisli, Suat; Dogan, Metin; Tasolar, Sevgi; Kahraman, Aysegul; Oztanir, Mustafa Namik; Sener, SerpilThe aim of this study is the evaluation of the vertebrobasilar artery system in patients with Behcet's and Neuro-Behcet's disease. For this aim; 20 adults with clinically diagnosed Behcet's disease, 20 adults with Neuro-Behcet's disease, and 19 age-and gender-matched controls were examined by magnetic resonance angiography (MRA). During MRA, diameters of left vertebral artery (LVA), right vertebral artery (RVA), basilar artery (BA), and proximal segment (P1) of posterior cerebral artery between origin and junction with the posterior communicating artery were measured. In all groups, LVA was dominant than RVA (P < 0.05). The diameters of BA and right P1 of Neuro-Behcet's disease were larger than the other groups (P < 0.05). In addition, the diameters of left P1 of Neuro-Behcet's disease were larger but not statistically significant. There is no difference between the groups in terms of gender. Behcet's disease can affect vascular structures; therefore vertebrobasilar artery system should be examined in patients with Behcet's and Neuro-Behcet's disease. (C) 2014 Wiley Periodicals, Inc.Öğe Fludrocortisone therapy in a newborn with cerebral salt wasting due to hypernatremia and severe hyperbilirubinemia(Churchill Livingstone, 2010) Karadag, Ahmet; Tabel, Yilmaz; Dogan, Derya Gumus; Aktas, Mumtaz; Aslan, Mehmet; Dogan, Metin[Abstract Not Available]Öğe Foramen magnum meningioma: The midline suboccipital subtonsillar approach(Elsevier Science Bv, 2016) Dogan, Metin; Dogan, Derya Gumus[Abstract Not Available]Öğe HETEROTOPIC OSSIFICATION; CASE REPORT(Aves, 2011) Oguzturk, Hakan; Turtay, Muhammet Gokhan; Dogan, Metin; Akgun, Feride SinemHeterotrophic ossification is the development of bone in abnormal areas like muscle tissue. Neurogenic, traumatic and congenital are just a few of the causes which vary a lot. The most significant factor affecting prognosis is prolonged immobilization. Emergency departments are places where immobile patients most frequently apply due to their varied complaints. In this report we presented an immobile patient with heterotrophic ossification and reviewed the literature. Heterotrophic ossification should be taken into consideration while assessing the possible causes of the complaints such as joint or extremity pain, restriction of movement in patients with immobilization.Öğe Investigation of a weak magnetic field effect on the in vitro catalytic activity of adenosine deaminase and xanthine oxidase(General Physiol And Biophysics, 2011) Batcioglu, Kadir; Dogan, Metin; Uyumlu, Ayse B.; Satilmis, Basri; Bayri, Nevzat; Atalay, Selcuk; Demirtas, HakanThe effect of a weak magnetic field (MF) on adenosine deaminase (ADA) and xanthine oxidase (XOD) activities have been investigated. A 50 Hz uniform MF was generated, and the magnitude of the field was kept constant at 5.8 mT. The changes in ADA activity over time were significantly different in and out of the MF; MF caused a steeper decline in ADA activity compared to the situation when no MF is present. In addition, MF caused a significant increase in XOD activity. There were no significant time-related changes for either enzyme in the absence of the MF. We suggest that a weak MF affects enzymatic systems.Öğe Jeune Sendromu(İnönü Üniversitesi Tıp Fakültesi Dergisi, 2011) Celiloglu, Ozgu Suna; Dogan, Metin; Ak, Muharrem; Dogan, Derya Gumus; Celiloglu, Can; Sigirci, Ahmet; Karadag, AhmetJeune sendromu; diğer adıyla ‘Asfiksik Torasik Displazi’ (ATD) daralmış göğüs kafesi, ekstremite anomalileri, solunum yetmezliği ve kayda değer yenidoğan mortalitesi ile karakterize otozomal resesif kalıtım gösteren nadir bir kondrodisplazidir. Bu sendrom bulunan çocukların çoğu şiddetli solunumsal yetmezlik gösterir ve erken süt çocukluğu döneminde ciddi ventilatör desteğine ihtiyaç duyabilir. Sendromun renal displazi, retinitis pigmentosa, hepatik ve pankreatik fibrozu içerebilen geniş bir klinik spektrumu mevcuttur. Doğum öncesi akondroplazi tanısı bulunan ve doğum sonrası ciddi solunumsal yetmezlik gösteren ve Jeune sendromu tanısı konulan bir hastayı sunduk.Öğe Letter to the Editor regarding recurrent sebaceous carcinoma of the eyelid: Outcome after postoperative reirradiation(Wiley-Blackwell, 2016) Dogan, Metin; Yildirim, Ismail Okan[Abstract Not Available]Öğe Letter to the Editor: regarding Lipomatous ependymoma: report of a rare differentiation pattern with a comprehensive review of literature(Springer Japan Kk, 2016) Dogan, Metin; Yildirim, Ismail Okan; Dogan, Derya Gumus[Abstract Not Available]Öğe Letter to the Editor: Regarding Neurologic Complications Caused by Epstein-Barr Virus in Pediatric Patients(Sage Publications Inc, 2016) Dogan, Metin; Dogan, Derya Gumus[Abstract Not Available]
