Person: BUĞDAYCI, ONUR
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BUĞDAYCI
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Publication Metadata only Radyolojik değerlendirmede genel prensipler(2018-04-22) BUĞDAYCI, ONUR; BUĞDAYCI O.Publication Metadata only Primer kemik sarkomlarında görüntüleme bulguları(2018-10-24) BUĞDAYCI, ONUR; BUĞDAYCI O.Publication Open Access Dual-Phase ADC Modelling of Breast Masses in Diffusion-Weighted Imaging: Comparison with Histopathologic Findings(AVES, 2018-05-16) BUĞDAYCI, ONUR; Ertas, Gokhan; Onaygil, Can; Bugdayci, Onur; Aribal, ErkinObjective: To investigate the diagnostic value of dual-phase apparent diffusion coefficient (ADC) compared to traditional ADC values in quantitative diffusion-weighted imaging (DWI) for differentiating between benign and malignant breast masses. Materials and Methods: Diffusion-weighted images of pathologically confirmed 88 benign and 85 malignant lesions acquired using a 3.0T MR scanner were analyzed. Small region-of-interests focusing on the highest signal intensity of lesions were used. Lesion ADC estimates were obtained separately from all b-value images (ADC; b=50, 400 and 800s/mm(2)), lower b-value images (ADC low; b=50 and 400s/mm2) and higher b-value images (ADC(high); b=400 and 800s/mm(2)). A set of dual-phase ADC (dpADC) models were constructed using ADC low, ADC high and a perfusion influence factor ranging from 0 to 1. Results: Strong positive correlation is observable between ADC and all dpADCs (rho=0.80-1.00). Differences in ADC and dpADCs between the benign and the malignant lesions are all significant (p<0.05). In detecting malignancy, traditional lesion ADC provides a good performance (AUC=89.9%) however dpADC(0.5) (dpADC with a factor of 0.5) accomplishes a better performance (AUC=90.8%). At optimal thresholds, ADC achieves 94.1% sensitivity, 72.7% specificity and 83.2% accuracy while dpADC(0.5) leads to 92.9% sensitivity, 79.5% specificity and 86.1% accuracy. Conclusion: Dual-phase ADC modelling may improve the accuracy in breast cancer diagnosis using DWI. Further prospective studies are needed to justify its benefit in clinical setting.Publication Metadata only El ve ayak bilek(2018-12-23) BUĞDAYCI, ONUR; BUĞDAYCI O.Publication Metadata only Üst ekstremitede kemik ve kıkırdak patolojileri(2017-12-17) BUĞDAYCI, ONUR; BUĞDAYCI O.Publication Open Access A very rare case of cervicothoracic vertebral synostosis spanning eight adjacent segments: congenital vs acquired(MARMARA UNIV, FAC MEDICINE, 2018-02-26) BUĞDAYCI, ONUR; Cengic, Ismet; Tureli, Derya; Altas, Hilal; Bugdayci, OnurAn elderly female presented with acute post-traumatic neck pain. Cervical roentgenogram revealed a long-segment cervicothoracic vertebral fusion spanning 8 adjacent spinal levels. The patient was evaluated with computed tomography (CT) and magnetic resonance (MR) imagings of the spine, electromyography (EMG) and growth differentiation factor 6 (GDF6) gene mutation analysis. Imaging findings were atypical for congenital block vertebrae and there was no GDF6 mutation. A revision of very old medical records and patient's recollections revealed long-term stay in sanatorium for rehabilitation of chronic partially-treated brucella spondylodiscitis during adolescence. Block vertebrae spanning several levels have previously been reported; but, this is the first report of an acquired cervicothoracic fusion spanning 8 adjacent vertebral bodies.Publication Metadata only Comparison of Doppler ultrasound and transient elastography in the diagnosis of significant fibrosis in patients with nonalcoholic steatohepatitis(SPRINGER, 2016) ÇELİKEL, ÇİĞDEM; Ergelen, Rabia; Yilmaz, Yusuf; Asedov, Ruslan; Celikel, Cigdem; Akin, Hakan; Bugdayci, Onur; Altun, Ersan; Tuney, DavutBackground: Liver fibrosis is an important prognostic determinant in patients with nonalcoholic steatohepatitis (NASH). Hepatic artery resistivity index (HARI) is a doppler ultrasonography (US) parameter that is used to follow up microcirculatory resistance in fatty liver. We aimed to asses whether it is possible to demonstrate significant fibrosis by means of doppler US in comparison with transient elastography (TE) and liver biopsy in NASH patients. Patients and methods: A total of 63 (mean age 47.1 +/- 8.4 years, 39 male, 24 female) biopsy-proven NASH patients were enrolled in this prospective study. The study population was classified into two groups: significant and no-significant fibrosis patients. Doppler US and TE were performed in two groups. Results: HARI and TE values were significantly higher in significant fibrosis group (0.81 +/- 0.05 vs. 0.63 +/- 0.14, p < 0.0005; 15.9 +/- 4.8 vs. 6.2 +/- 2.6 kilopascals, p < 0.0005; respectively). Based on the ROC curve, the optimal cut-off value of HARI for a significant fibrosis was >0.75, which yielded a sensitivity of 78% and a specificity of 75%, with the area under the curve at 0.90. The optimal cut-off value of TE for a significant fibrosis was >9.8 kilopascals, which yielded a sensitivity of 90% and a specificity of 91%, with the area under the curve at 0.95. HARI values were moderately correlated with TE values (r = 0.53, p < 0.001). Conclusion: Doppler US has moderate % sensitivity and % specificity, which is lower compared with TE for the diagnosis significant fibrosis. However, it may be used as an alternative method for the assessment of fibrosis in patients with NASH who are not good candidates for TE evaluation.Publication Metadata only The effectiveness of ultrasonography and ultrasonographic elastography in the diagnosis of carpal tunnel syndrome and evaluation of treatment response after steroid injection(ELSEVIER IRELAND LTD, 2018) EKİNCİ, GAZANFER; Asadov, Ruslan; Erdal, Ayse; Bugdayci, Onur; Gunduz, Osman Hakan; Ekinci, GazanferPurpose: To evaluate if there is a place for ultrasonography (US) and ultrasonographic elastography (UE) in the diagnosis and follow up of carpal tunnel syndrome treatment. Materials and methods: The study was performed on 25 patients (study group) and 17 healthy volunteers (control group). Measured US and UE criteria were median nerve area (MNA), proximal median nerve area (pMNA), difference between MNA and pMNA (dMNA) and strain values of carpal tunnel content (CTC) and median nerve (MN). Patients in the study group were also evaluated using the Boston questionnaire, Visual Analogue Scale (VAS) and nerve conduction studies. Thirty-three wrists in 23 patients received steroid injections on the same day. Patients were re-evaluated 6 weeks after steroid injection. To establish a cut off value for MNA, ROC Curve analysis was used. Results: Mean MNA and dMNA values in the control group were significantly lower than in the study group (7.33 +/- 1.31 vs. 15.44 +/- 5.10; p = < 0.05 and 1.58 +/- 0.75 vs. 8.91 +/- 4.93; p = 0.00 respectively). Median nerve and CTC strain indices were significantly higher in the control group (p = 0.00 and p = 0.036). Decrease in MNA and dMNA values after treatment was meaningful (p = 0.00). While there was no significant change in MN elasticity, mean CTC strain index of the study group (4.680 +/- 1.664) decreased significantly after treatment (3.621 +/- 1.054 p = 0.002). This decrease in the CTC index was more pronounced in patients who benefited from treatment (p = 0.001). Conclusion: US and UE can be useful in the diagnosis of CTS and its response to treatment, if used together with clinical and electroneurophysiological tests.Publication Metadata only Thyroid fine needle aspiration biopsy: Do we really need an on-site cytopathologist?(ELSEVIER IRELAND LTD, 2014) TÜRELİ, DERYA; Cengic, Ismet; Tureli, Derya; Ahiskali, Rengin; Bugdayci, Onur; Aydin, Hilal; Aribal, ErkinPurpose: The aim of this single center study is to evaluate the effectiveness of performing ultrasound-guided thyroid fine-needle aspiration biopsies (FNAB) performed by the radiologist alone without an on-site cytopathologist. Materials and methods: In this prospective randomized study, 203 patients with single nodules measuring 10 mm or more underwent ultrasound-guided FNAB: 102 patients underwent FNAB performed by the radiologist accompanied by a cytopathologist (control group); 101 patients underwent FNAB by the radiologist alone (study group). In both groups biopsy time, specimen adequacy ratio, total aspiration number, cytopathologist's cytological diagnosis time (t1), cytopathologist's total time consumption (t2) were evaluated. Results: Mean total biopsy time was 8.74 +/- 2.31 min in the study group and was significantly shorter than the control group's 11.97 +/- 6.75 min (p = 0.004). The average number of aspirations per patient in the study group was 4.00 +/- 0; compared to the control group's 3.56 +/- 1.23 this was significantly higher (p = 0.001). t1 of the study group was 307.48 +/- 226.32 s; compared to 350.14 +/- 247.64 s in the control group, there was no statistically significant difference (p = 0.137). t2 of the study group was 672.93 +/- 270.45 s; compared to the control group (707.03 perpendicular to 258.78 s) there was no statistically significant difference (p = 0.360). Diagnostic adequacy of aspirated specimens was reassessed in the pathology laboratory. In the study group, 84 out of 101 aspirations and in the control group 89 out of 102 aspirations was determined as adequate with no statistically significant difference (p = 0.302). Conclusions: We believe that in centers where a cytopathologist is not available, ultrasound-guided thyroid FNAB can be adequately performed by an experienced radiologist who was effectively trained in smear preparation. (C) 2014 Elsevier Ireland Ltd. All rights reserved.Publication Open Access Ultrasound and MRI features of lipomatosis of the median nerve: A case study(MARMARA UNIV, FAC MEDICINE, 2018-10-31) GÜNDOĞMUŞ, CEMAL AYDIN; Gundogmus, Cenral Aydin; Bugdayci, Onur; Aribal, Mustafa ErkinWe present a case of a 10 year-old girl with slowly enlarging, painless mass at the volar aspect of her left hand. The lesion had been present since infancy. Diagnosis was lipomatosis of the median nerve which is a very rare, benign tumor involving peripheral nerves. Magnetic resonance imaging (MRI) and ultrasound (US) features of this lesion are discussed.