Person:
BUĞDAYCI, ONUR

Profile Picture

Email Address

Birth Date

Research Projects

Organizational Units

OrgUnit Logo
Organizational Unit

Job Title

Last Name

BUĞDAYCI

First Name

ONUR

Name

Filters

2006 - 200932010 - 201919
Reset filters

Settings

End date: 2019 ×

Search Results

Now showing 1 - 10 of 22
  • No Thumbnail Available
    PublicationMetadata only
    Radyolojik değerlendirmede genel prensipler
    (2018-04-22) BUĞDAYCI, ONUR; BUĞDAYCI O.
  • No Thumbnail Available
    PublicationMetadata only
    Nodüler tiroid hastalıklarında USG ve renkli doppler USG bulgularının histopatolojik ve sitolojik bulgularla korelasyonu
    (2006-09-10) BUĞDAYCI, ONUR; GÜLLÜOĞLU, MAHMUT BAHADIR; AHISKALI, ASİYE RENGİN; ASLAN A., SANCAK S., aslan m., BUĞDAYCI O., GÜLLÜOĞLU M. B. , AHISKALI A. R. , akalın s., arıbal e.
  • No Thumbnail Available
    PublicationMetadata only
    Primer kemik sarkomlarında görüntüleme bulguları
    (2018-10-24) BUĞDAYCI, ONUR; BUĞDAYCI O.
  • Thumbnail Image
    PublicationOpen 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, Erkin
    Objective: 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.
  • No Thumbnail Available
    PublicationMetadata only
    El ve ayak bilek
    (2018-12-23) BUĞDAYCI, ONUR; BUĞDAYCI O.
  • No Thumbnail Available
    PublicationMetadata only
    Ultrasonografi̇ ile tanimlanan sternum kırığı
    (2006-10-16) LAÇİN, TUNÇ; BUĞDAYCI, ONUR; ÇİMŞİT, NURİ ÇAGATAY; BOSTANCI, KORKUT; YÜKSEL, MUSTAFA; CENGİÇ İ., LAÇİN T., BUĞDAYCI O., AKPINAR İ. N. , ÇİMŞİT N. Ç. , BOSTANCI K., YÜKSEL M.
  • No Thumbnail Available
    PublicationMetadata only
    Üst ekstremitede kemik ve kıkırdak patolojileri
    (2017-12-17) BUĞDAYCI, ONUR; BUĞDAYCI O.
  • Thumbnail Image
    PublicationOpen 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, Onur
    An 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.
  • No Thumbnail Available
    PublicationMetadata 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, Davut
    Background: 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.
  • No Thumbnail Available
    PublicationMetadata only
    Siroz hastalarında hepatosellüler karsinom taramasında altı ayda bir yapılan batın ultrasonografi ve serum alfa-feto protein ölçümüne ek olarak, yılda bir kez yapılan batın manyetik rezonans görüntülemesinin erken tanıya olan katkısı
    (2006-10-11) BUĞDAYCI, ONUR; GÜNDÜZ, FEYZA; ÖZDOĞAN, OSMAN CAVİT; TÜNEY, DAVUT; BUĞDAYCI O., Sever A., DİLBER F., KEDRAH A. E., TİFTİKÇİ A., AKIN H., ERZEN T. C., TÖZÜN A. N., ÖZDOĞAN O. C., TÜNEY D.