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Featured researches published by Özgür Demir.


Scandinavian Journal of Rheumatology | 2006

Characteristics of vascular involvement in Behçet's disease.

Nurşen Düzgün; Aşkın Ateş; Olcay Tiryaki Aydintug; Özgür Demir; Ümit Ölmez

Objective: Behçets disease (BD) is a multisystemic inflammatory disorder classified among the vasculitides, which can affect all types and sizes of blood vessels. Vascular involvement may be seen in 25–50% of BD patients. In this study, we examined the characteristics of vascular involvement in patients with BD. Methods: One hundred and eighty patients with BD were included in the study. The diagnosis of vascular involvement was made on clinical signs, by Doppler ultrasonography and/or angiography using computed tomographic or magnetic resonance techniques where appropriate. Detailed clinical characteristics were recorded for each patient. Results: Seventy‐one patients (39.4%) had vascular involvement. In patients with vascular lesions, the frequency of male sex was significantly higher than in patients without vascular lesions (89.8% vs. 63.3%, respectively; p<0.001). Of 71 BD patients with vascular involvement, 68 had venous lesions (95.8%). Three patients had arterial lesions without venous thrombosis. Eleven patients had arterial involvement with venous thrombosis. The most frequent type of vascular involvement was deep venous thrombosis in the lower extremities (n = 56, 78.9%). There was a significant association between deep venous thrombosis and superficial thrombophlebitis (r = 0.325, p<0.01). Twenty‐four patients (33.8%) had vena cava thrombosis and two had vena hepatica thrombosis. In patients with vascular involvement, the frequency of erythema nodosum was significantly higher (p = 0.001) and the frequency of ocular involvement was significantly lower (p<0.05) than in patients without vascular involvement. Conclusion: Our study illustrates the frequency and significance of vascular involvement in BD.


Thyroid | 2012

Ultrasound Elastography Is Not Superior to Grayscale Ultrasound in Predicting Malignancy in Thyroid Nodules

Uğur Ünlütürk; Murat Faik Erdogan; Özgür Demir; Sevim Gullu; Nilgun Baskal

BACKGROUND Several studies have evaluated the ability of ultrasound elastography (USE) to diagnose malignant nodules. However, these studies had important limiting factors, selection bias and small sample size. The aims of the present study were to prospectively assess, in a large group of patients, the diagnostic power of USE for detecting malignancy in thyroid nodules, and to compare this technique with B-mode grayscale ultrasonography (BUS) and power Doppler ultrasonography (PD). METHOD There were 194 patients with 237 thyroid nodules who were examined using BUS, PD, and USE. USE scores were classified according to the elasticity: score 1 as high, score 2 as intermediate, and score 3 as low (i.e., a high degree of stiffness). Fine-needle aspiration cytology (FNAC) was performed in all nodules at least two different times. Nodules having two benign FNAC readings that did not change the diameter during a 6-month follow-up period were classified as benign. Patients having thyroid nodules with indeterminate, suspicious, or malignant cytology had total or hemithyroidectomy to remove the nodule and treat the malignancy. RESULTS Fifty eight (25%) nodules in 45 (23%) patients were found to be malignant. USE had a limited sensitivity and a positive predictive value in detecting malignant thyroid nodules and was not superior to BUS. USE had almost the same specificity and a negative predictive value as BUS. A power Doppler type-3 pattern was not of sufficient sensitivity to detect malignancies in thyroid nodules. CONCLUSIONS In contrast to earlier reports, this current study noted a lower sensitivity and specificity of USE for the diagnosis of malignancy in thyroid nodules than previously reported.


Archives of Medical Science | 2013

Metabolic syndrome prevalence according to ATP III and IDF criteria and related factors in Turkish adults.

Kursat Gundogan; Fahri Bayram; Vedia Tonyukuk Gedik; Ahmet Kaya; Ahmet Karaman; Özgür Demir; Tevfik Sabuncu; Derya Kocer; Ramazan Coskun

Introduction The aim of this study is to investigate the prevalence of metabolic syndrome (MS) and its components according to Adult Treatment Panel III (ATP III) and International Diabetes Federation (IDF) criteria and the risk factors affecting MS. Metabolic syndrome prevalence was evaluated according to certain quintet age groups, altitude, location and demographic features. Material and methods This study was a cross-sectional survey conducted in 24 provinces from the 7 regions of Turkey. A total of 4309 adults from 7 regions participated in the study (1947 males, 45.2%). Results The mean age of participants was 47 ±14 years. Metabolic syndrome prevalence was found as 36.6% according to ATP III and 44.0% according to IDF. The MS rate was found to be higher in females compared to males in both groups (p < 0.01). According to both criteria, MS prevalence was found to be higher in subjects who lived in coastal regions when evaluated according to altitude and in subjects who lived in district centers when evaluated according to location. The MS risk is 1.62-fold higher in females compared to males. Metabolic syndrome risk increases as age increases and is highest in the 61-65 age group. Metabolic syndrome risk increases 2.75-fold in the overweight compared to normal weighing subjects and 7.80-fold in the obese. Conclusions Metabolic syndrome prevalence was found to be high in Turkey according to both criteria. Metabolic syndrome prevalence increases as age and body mass index (BMI) increase. Age, female gender and obesity are independent risk factors for MS development.


Thyroid | 2009

More Than a Decade of Iodine Prophylaxis Is Needed to Eradicate Goiter Among School Age Children in a Moderately Iodine-Deficient Region

Murat Faik Erdogan; Özgür Demir; Ahmet Nuri Kamel; Gurbuz Erdogan

BACKGROUND There are many studies regarding the effect of iodine supplementation on goiter, but relatively few reports on the duration of iodine supplementation required to eradicate goiter in iodine-deficient regions. In the current study, we aimed to determine goiter prevalence as determined by sonographic methods, as it relates to changes in median urinary iodine concentrations (UIC) among school age children (SAC), ages 9-11. METHODS This study was performed in Ankara, Turkey, before and 5-10 years after mandatory iodination of table salt. Three hundred to 400 SAC from the same primary schools were studied every year by measurement of UIC as part of Turkish Iodine Surveys. Sonographically determined thyroid volume of the SAC had been measured before the mandatory iodination in 1997 and 5-10 years afterward, in 2002 and 2007. The prevalence of goiter in children was evaluated using World Health Organization/International Council for the Control of Iodine Deficiency Disorders recommendations for age and sex. RESULTS Moderate iodine deficiency was present in 1997 (median UIC, 25.5 microg/L), and it improved to mild iodine deficiency in 2001 (median UIC, 87 microg/L). Sufficient iodine intake (median UIC, 117 microg/L) was achieved by the year 2004. Goiter prevalence was 25% in 1997, 12.3% in 2001, and decreased to 1.3% in 2004. CONCLUSION The time required to normalize the prevalence of goiter in SAC living in a moderately iodine-deficient environment was at least a decade. To achieve a goiter rate of less than 5% among SAC, it may require that, as a population, they were born and grew up under conditions of iodine sufficiency.


Clinical Endocrinology | 2012

The role of ultrasound elastography in preoperative localization of parathyroid lesions: a new assisting method to preoperative parathyroid ultrasonography.

Uğur Ünlütürk; Murat Faik Erdogan; Özgür Demir; Cavit Culha; Sevim Gullu; Nilgun Baskal

Background  After the definition of minimally invasive procedures, preoperative localization of parathyroid lesions is now crucial. False‐positive results up to 30% were reported by B‐mode grayscale ultrasonography (US) in localization of parathyroid lesions. Parathyroid adenomas are relatively stiff lesions. Ultrasound elastography (USE) can accurately evaluate tissue stiffness and might detect the stiff parathyroid lesions.


Nuclear Medicine Communications | 2016

Clinical significance of thyroid incidentalomas identified by 18F-FDG PET/CT: correlation of ultrasonograpy findings with cytology results.

Özgür Demir; Naziyet Köse; Elgin Ozkan; Uğur Ünlütürk; Gulseren Aras; Murat Faik Erdogan

AimThe aim of this study was to investigate the clinical importance of incidental focal or diffuse fluorine-18 fluorodeoxyglucose (18F-FDG) uptake in the thyroid gland on positron emission tomography (PET)/computed tomography (CT) and to evaluate the additive value of thyroid ultrasonography (US) in defining the malignancy potential of thyroid incidentalomas. Patients and methodsA total of 1450 patients, who had undergone a PET/CT scan for staging or restaging of various malignancies, were screened retrospectively and 52 (3.6%) patients with focal or diffuse 18F-FDG uptake in the thyroid gland on PET/CT were enrolled in the study. None of the patients had any history of thyroid diseases. Thyroid US with elastography for a thyroid nodule was performed for all the patients cross-sectionally. Thyroid fine-needle aspiration biopsy (FNAB) was also applied at the same time as the thyroid US to 34 patients with a nodule(s) 10 mm or more in diameter or less than 10 mm, but with malignancy potential ultrasonographically. The cytology results were compared with the thyroid US and 18F-FDG PET/CT findings. ResultsAlthough 39 patients had focal (group 1) 18F-FDG uptake in the thyroid gland, the remaining 13 patients had diffuse (group 2) uptake. In group 1, FNAB was performed in 32 patients. In 10 of 32 (31%) patients, FNAB results were concordant with malignant cytology (seven primary thyroid malignancy and three metastasis to thyroid). In group 2, in one of two patients who had undergone FNAB, malignant cytology (metastasis to thyroid) was detected. Although the difference between the maximum standardized uptake value (SUVmax) of malignant and benign nodules was statistically significant (10.2±8.9 vs. 5.6±3.0, P=0.013), the difference between the nodule sizes was not statistically significant (20.0±7.3 vs. 16.7±7.4, P=0.923). The presence of suspicious US findings and a high elastography score (≥4) were also statistically significant (P<0.001 and P=0.035, respectively). In the receiver–operator characteristic analysis, a 5.3 cut-off SUVmax was calculated with 82% sensitivity and 65% specificity for predicting malignant cytology. ConclusionFocal 18F-FDG uptake was associated with a higher prevalence of malignant thyroid nodule compared with diffuse 18F-FDG uptake. In particular, if a focal thyroid incidentaloma with high SUVmax (>5.5), suspicious US findings, and a high elastography score (≥4) is detected, a pathological diagnosis, either by histology or by cytology examination, should be made, especially when the patient has a long life expectancy.


Turkish Neurosurgery | 2012

Improvement in remission rates of the first operation in acromegalic patients.

Özgür Demir; Gedik; Demet Corapcioglu; Unlu Ma; Murat Faik Erdogan; Sevim Gullu; Ali Riza Uysal; Nilgun Baskal

AIM The aim of the study was to determine the remission rates of the first operation with respect to the number of surgeons and the parameters important for the prediction of the success. MATERIAL AND METHODS The study cohort consisted of 180 acromegalic patients who presented over a 29 year. All the patients had undergone transnasal transsphenoidal adenomectomy and then octreotide treatment and/or radiotherapy were applied to the patients who were not cured. Remission criteria was accepted as nadir GH < 1 μg/L with oral glucose tolerance test (OGTT) and normal IGF-1 with respect to age and gender. RESULTS The postoperative median follow up period was 84 months (range 6-372 months). The remission rate of the first operation before 2003 was 20%, but this rate increased to 51% after 2003 (p=0.018). The most impressive improvement was due to the single experienced surgeon (49% vs. 5.3%) (p < 0.001). The success of the first operation was determined by the tumor size, microadenomas were more successfully treated than macroadenomas (p=0.014). The prevalence of discordance between GH and IGF-1 was 24% in patients cured after first surgery. CONCLUSION The clinical recognition of acromegaly and outcomes of single experienced surgeons in specialized centers have significantly improved over the last years.


Archives of Medical Science | 2012

Hypothyroidism, new nodule formation and increase in nodule size in patients who have undergone hemithyroidectomy

Reyhan Ersoy; Cuneyd Anil; Özgür Demir; Murat Faik Erdogan; Sevim Gullu; Dilek Berker; Kamile Gul; Uğur Ünlütürk; Gurbuz Erdogan

Introduction The current medical literature has conflicting results about factors related to hypothyroidism and nodular recurrences during follow-up of hemithyroidectomized patients. We aimed to evaluate factors that may have a role in new nodule formation, hypothyroidism, increase in thyroid lobe and increase in nodule volumes in these patients with and without Hashimotos thyroiditis (HT), and with and without levothyroxine (LT4) use. Material and methods We enrolled 140 patients from five different hospitals in Ankara and evaluated their thyroid tests, autoantibody titre results and ultrasonographic findings longitudinally between two visits with a minimum 6-month interval. Results In patients with HT there was no significant difference between the two visits but in patients without HT, thyroid stimulating hormone (TSH) levels and nodule volume were higher, and free T4 levels were lower in the second visit. Similarly, in patients with LT4 treatment there was no difference in TSH, free T4 levels, or lobe or nodule size between the two visits, but the patients without LT4 had free T4 levels lower in the second visit. Regression analysis revealed a relationship between first visit TSH levels and hypothyroidism during follow-up. Conclusions Patients who have undergone hemithyroidectomy without LT4 treatment and without HT diagnosis should be followed up more carefully for thyroid tests, new nodule formation and increase in nodule size. The TSH levels at the beginning of the follow-up may be helpful to estimate hypothyroidism in hemithyroidectomized patients.


Endocrine Practice | 2016

DISCORDANCE BETWEEN GH AND IGF-1 LEVELS IN TURKISH ACROMEGALIC PATIENTS

Ethem Turgay Cerit; Kemal Agbaht; Özgür Demir; Mustafa Şahin; Vedia Tonyukuk Gedik; Cem Özcan; Demet Corapcioglu

OBJECTIVE Discordance between insulin-like growth factor-1 (IGF-1) and growth hormone (GH) levels is an important problem in the follow-up of patients diagnosed with acromegaly. Our aims were to evaluate the discordance between IGF-1 and GH levels and compare the performance of different cut-off levels for the nadir in GH (GHn) in acromegalic patients. METHODS The study included 63 acromegalic patients in a follow-up at a tertiary care university hospital facility. Levels of IGF-1, IGF binding protein-3 (IGFBP-3), and GH were investigated. The baseline GH and GHn levels were evaluated after an oral glucose tolerance test (cut-offs of 0.4 and 1 ng/mL, respectively). The discordance rates between GHn and IGF-1 levels, and IGF-1/IGFBP-3 ratios were determined. RESULTS We first adopted a GHn cut-off value of 1 ng/mL and found that 27 patients (42.9%) exhibited biochemical remission (BR) (IGF-1 <95th percentile, GH <1), and 25 patients (39.7%) had no BR (NBR) (IGF-1 ≥95th percentile, GH >1). Discordance in the presence of normal IGF-1 and nonsuppressed GH (DC1) occurred in 2 of 63 (3.2%) patients; discordance in the presence of high IGF-1 and suppressed GH (DC2) occurred in 9 of 63 (14.3%) patients. If the GHn cut-off value adopted was 0.4 ng/mL, the distributions were 17 of 63 (27.0%) patients in BR, 29 of 63 (46.0%) patients in NBR, 12 of 63 (19.0%) in DC1, and 5 of 63 (7.9%) patients in DC2. If only the baseline GH values were considered, the distributions were very similar to those with a GHn cut-off value of 0.4 ng/mL. The IGF-1/IGFBP-3 ratio was lowest in the BR group. CONCLUSION Adopting a GHn cut-off value of 0.4 ng/mL did not increase the test performance compared with baseline GH only. In contrast, in the follow-up of acromegalic patients, the IGF-1/IGFBP-3 ratio might be a useful measurement when discordance between IGF-1 and GH levels occurs. We propose that these values be considered in clinical practice. ABBREVIATIONS BR = biochemical remission DC1 = discordance group 1 DC2 = discordance group 2 DM = diabetes mellitus GH = growth hormone GHn = nadir in GH IGF-1 = insulin-like growth factor-1 IGFBP-3 = IGF binding protein-3 LAR = long-acting release NBR = not in biochemical remission OGTT = oral glucose tolerance test.


Clinical Endocrinology | 2018

Diagnostic accuracy of parathyroid hormone levels in washout samples of suspicious parathyroid adenomas: A single‐centre retrospective cohort study

Asena Gokcay Canpolat; Mustafa Şahin; Elif Ediboğlu; Murat Faik Erdogan; Sevim Gullu; Özgür Demir; Demet Corapcioglu

Minimally invasive surgery is an alternative surgical approach for primary hyperparathyroidism with less surgical trauma and anaesthesia complications. When combined with intraoperative measurement of parathyroid hormone (PTH), cure rates are exceeding 97%. Preoperative intact PTH determination in washout samples is really very useful when parathyroid lesions cannot be easily distinguished from thyroid lesions or sometimes lymph nodes. Herein, we aimed to report our institutional experience about parathyroid fine‐needle aspiration (FNA) method and suggest a cut‐off ratio for this purpose.

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Erol Öksüz

Gaziosmanpaşa University

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