Browsing by Author "Gunduz, Ali Mahir"
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Article Anterior Cerebral Artery and Anterior Communicating Artery Variations: Assessment With Magnetic Resonance Angiography(Elsevier Science inc, 2021) Yokus, Adem; Toprak, Nursen; Gunduz, Ali Mahir; Akdeniz, Huseyin; Akdemir, Zulkuf; Dundar, Ilyas; Arslan, HarunBACKGROUND: Although anterior cerebral artery (ACA) and anterior communicating artery (AcomA) variations have been frequently investigated by contrast enhanced angiography, the number of studies performed with magnetic resonance angiography is quite low. Our aim in this study is to investigate ACA and AcomA variations with time of flight magnetic resonance angiography (TOF MRA). METHODS: Source and maximum intensity projection images of 581 adult patients (273 males, 308 females) who were scanned for intracranial arteries with the TOF MRA method were retrospectively analyzed. RESULTS: We found the typical configuration rate of the ACA and AcomA complex to be 40.6%. The most common structural anatomic variations out of typical configuration were AcomA aplasia (18.9%) and AcomA hypoplasia (17.9%), respectively. The least frequent variation that we found was duplicated AcomA (0.9%). When we examined gender comparatively, unilateral A1 segment aplasia was found to be higher in males and azygos ACA was found to be higher in females (P = 0.001 and P = 0.029, respectively). CONCLUSIONS: In this study, in which we used the TOF MRA technique, we detected high rates of anatomic variations of ACA and AcomA. This method, which is noninvasive, does not require contrast material and does not contain ionizing radiation, can be preferred especially in the evaluation of patients with kidney disease and contrast allergy.Article Assessment of Stromal Elastin Fibers in Breast Cancer and Fibroadenomas: Is There a Correlation With Ultrasound Elastography Findings(Galenos Yayincilik, 2022) Toprak, Nursen; Aras, Ibrahim; Toktas, Osman; Yokus, Adem; Gunduz, Ali MahirObjective: The stiffness of a breast lesion provides information on the likelihood of malignancy. The most important factor affecting this stiffness is the composition of the extracellular matrix (ECM). The aim of this study was to assess the elastin fiber contents of malignant breast lesions and fibroadenomas and investigate any relationship between the shear wave velocity (SWV) measured by ultrasonography, and the elastin fiber content of lesions. Materials and Methods: Consecutive patients with breast lesions were enrolled. The SWV values of the lesions were analyzed. Histopathological analysis of elastin in excised lesions was performed by the method of Shivas and Douglas. Breast cancer patients were reviewed according to their lymph node status and tumor diameter. The relationship between SWV value and tissue elastin fiber score was analyzed. The correlation between breast cancer grade and elastin fiber score in malignant lesions was investigated. Results: A total of 167 consecutive breast lesions in 167 patients were included in this study (75 invasive cancer, 92 fibroadenomas). High elastic fiber score was significantly more common (p = 0.001) in malignant lesions (n = 61; 81.3%) than fibroadenomas (n = 13; 14.1%). There was a negative correlation between the mean SWV and the elastin fiber score of fibroadenomas (p = 0.001). A low grade in breast cancer was associated with high elastin fiber score (p = 0.01). Conclusion: Malignant lesions tend to have higher elastin fiber scores than fibroadenomas. Elastin fiber assessment may provide additional prognostic information in malignant lesions. Changes in elastin fiber content may account for the variation in elasticity in fibroadenomas.Article Comparing the Interpretation of Diffusion-Weighted Magnetic Resonance Images Made by Emergency Physicians and On-Call Radiologists(Emergency Medicine Physicians Assoc Turkey, 2018) Sasmaz, Muhammed Ikbal; Akca, Ali Haydar; Guven, Ramazan; Altan, Burak; Baraz, Nuri; Kirpat, Vedat; Gunduz, Ali MahirAim: Stroke is a leading cause of adult disability and death worldwide. It is very important to determine the ischemic tissue at risk in stroke patients. Although brain computed tomography (CT) is the first and standard imaging technique, diffusion-weighted magnetic resonance imaging (DW-MRI) is superior to CT and is the optimal imaging technique for the diagnosis of acute ischemic stroke. In our study, we aimed to compare the interpretation of DW-MRI between emergency physicians (EP) and on-call radiologists (OCRs). Materials and Methods: This multi-centered, prospective study was conducted at three central hospitals from June 1, 2016 to May 31, 2017. DW-MRI images of the patients were first interpreted by the EP and then by the OCR. Finally, DW-MRI images were interpreted by a definitive result team comprised of two radiologists who were blinded to the study. Sensitivity, specificity, positive predictive value, negative predictive value, and. coefficient were calculated. Results: In total, 315 patients' DW-MRI images were examined. The interpretation sensitivity and specificity rates of the DW-MRI images for EPs were 95.1% and 98.7%, respectively, whereas those for OCRs were 98.8% and 98%, respectively. There was almost perfect agreement (kappa value > -0.80) regarding DW-MRI interpretations of both OCRs and EPs. Conclusion: Our study showed that EPs were very successful in interpreting DW-MRI after a short-term training.Article Does Arfi Elastography Complement B-Mode Ultrasonography in the Radiological Diagnosis of Idiopathic Granulomatous Mastitis and Invasive Ductal Carcinoma(Sage Publications Ltd, 2022) Toprak, Nursen; Toktas, Osman; Ince, Suat; Gunduz, Ali Mahir; Yokus, Adem; Akdeniz, Huseyin; Ozkacmaz, SercanBackground Idiopathic granulomatous mastitis (IGM) is a chronic, unpleasant autoimmune inflammatory condition and is clinically and radiologically often confused with breast malignancy. Purpose To investigate the contributions of qualitative and quantitative aspects of acoustic radiation force impulse (ARFI) elastography to the differential diagnosis between IGM and invasive ductal carcinoma (IDC) in the breast. Material and Methods Ninety-four women with IDC and 39 with IGM were included in the study. Shear wave velocity (SWV) was calculated for all lesions using quantitative elastography. Next, each lesion's correspondence on qualitative elastographic images to those on the B-mode images was evaluated: pattern 1, no findings on elastography images; pattern 2, lesions that were bright inside; pattern 3, lesions that contained both bright and dark areas; and pattern 4, lesions that were dark inside. Pattern 4 was subdivided into 4a (dark area same size as lesion) and 4b (dark area larger than lesion size). Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were calculated. Results The mean SWV based on ARFI elastography was 3.78 +/- 1.26 m/s for IGM and 5.34 +/- 1.43 m/s for IDC lesions (P < 0.05). Based on qualitative ARFI elastography, IDC lesions were mostly classified as pattern 4b, while IGM lesions were mostly classified as pattern 1 or 2 (P = 0.01). Evaluation of both the qualitative and quantitative aspects of ARFI elastography yielded a sensitivity of 89% and specificity of 84%. Conclusion ARFI elastography may facilitate the differential diagnosis between IGM and IDC.Article Does Chronic Delta Hepatitis Increase Risk of Celiac Disease(Allied Acad, 2017) Temur, Atilla; Gunduz, Ali Mahir; Dulger, Ahmet Cumhur; Akca, Ali HaydarCeliac disease is a small intestinal malabsorption syndrome whose importance remains underappreciated. This is underestimated by the fact that it remains under recognized in almost 90% of patients. Hepatitis D virus (HDV) infection is a serious health problem leading to cirrhosis and hepatocellular carcinoma. Furthermore, the impact of on the clinical picture in patients with chronic HDV infection, with regards to laboratory parameters is not clear. So, we examined this relationship using recent hospital-based data. We analyzed data from 50 delta hepatitis patients (mean age 52.5 +/- 12.8 years; 30 male). 21 of them had cirrhosis. Both groups were screened for serum tissue transglutaminase antibodies and immunoglobulin A, and those antibody-positive were further investigated by intestinal biopsy. Histopathological examination was performed according to Marsh classification. Demographic features and laboratory data were compared between groups. There were six (28.5%) seropositivity of TTG IgG among patients with delta hepatitis related cirrhosis. No patient tested positive for TTG IgA in cirrhotic group whereas, there were no positive results for both TTG IgA and G among non-cirrhotic delta hepatitis group. In cirrhotic group, the rate of TTG IgG seropositivity was higher than those without cirrhosis (p=0.036). Seropositivity of TTG IgG was correlated with higher MELD scores (p<0.05). Higher rate of seropositivity of TTG IgG antibodies and CD among patients with chronic HDV-related cirrhosis may reflect a unique phenomenon that requires further investigation to determine underlying causative factors.Article The Effect of Computed Tomography on Oxidative Stress Level and Some Antioxidant Parameters(Sage Publications Ltd, 2021) Gunduz, Ali Mahir; Demir, Halit; Toprak, Nursen; Akdeniz, Huseyin; Demir, Canan; Arslan, Ayse; Goya, CemilBackground X-rays are defined as ionizing radiation and hydrolyze the water, causing free radical formation. Oxidative stress is the damage that occurs in cells due to the lack of antioxidants, which detoxifies them, with the increased production of free radicals that occur during normal cellular metabolism. Purpose To examine the acute effects of computed tomography (CT), i.e. ionizing radiation, on oxidative stress and antioxidant defense mechanisms. Material and Methods The study included a total of 53 patients that were selected among the patients that underwent non-contrast full-body CT. Malondialdehyde (MDA) and reduced glutathione (GSH) levels and superoxide dismutase (SOD) and catalase (CAT) activities were investigated in blood samples taken from patients. Results The post-scan levels of MDA increased significantly while the post-scan levels of GSH, SOD, and CAT decreased significantly compared to their pre-scan levels. Conclusion CT, which is a widely used X-ray imaging technique and has numerous known side effects, was found to increase the levels of MDA, which is an indicator of oxidative stress, and to decrease the levels of some antioxidants including GSH, SOD, and CAT.Article Evaluation of Distal Femoral Cartilage by B-Mode Ultrasonography and Shear Wave Elastography in Patients With Knee Osteoarthritis: a Preliminary Study(Sage Publications Ltd, 2021) Yokus, Adem; Toprak, Murat; Arslan, Harun; Toprak, Nursen; Akdeniz, Huseyin; Gunduz, Ali MahirBackground Degenerative change in articular cartilage is one of the most important factors in the development of osteoarthritis. Shear wave elastography can be used to identify pathologic cartilage. Purpose To evaluate distal femoral cartilage by shear wave elastography in patients with symptomatic knee osteoarthritis. Material and methods Twenty patients with bilateral knee osteoarthritis (study group) and 20 volunteers with the same demographic characteristics but without symptomatic knee pain (control group) were included in the study. A total of 80 knee joints of 40 individuals were evaluated. At the medial, intercondylar, and lateral condylar levels distal femoral cartilage thickness was measured by B-mode ultrasonography and stiffness was measured by shear wave elastography. Results The medial, intercondylar, and lateral cartilage thickness measurements were similar between the two groups and no statistically significant difference was observed (P = 0.711,P = 0.766, andP = 0.575, respectively). The shear wave velocity values in the medial and intercondylar cartilage were significantly higher in the study group (P = 0.002). Shear wave velocity values measured from lateral cartilage were higher in the study group and the difference between the groups had a borderline statistical significance (P = 0.053). Conclusion Shear wave elastography seems to be a reliable, non-invasive, and acceptable method for the assessment of pathologic cartilage.Article The Role of Elastography in Reducing Unnecessary Biopsies in Bi-Rads 4a and 4b Breast Lesions(Springer india, 2024) Toprak, Nursen; Yokus, Adem; Gunduz, Ali Mahir; Durmaz, Fatma; Ilik, Zehra AkmanMany benign breast lesions in the Breast Imaging Reporting and Data System (BI-RADS) 4 category defined by ultrasonography (US) undergo unnecessary biopsies. This study aims to investigate the efficiency of acoustic radiation for impulse elastography (ARFI) in diagnosing BI-RADS 4 breast lesions. The ARFI elastography technique was utilized to assess the lesions both qualitatively and quantitatively. By using quantitative elastography measurement, we found that the shear wave velocity (SWV) of BI-RADS 4a lesions was significantly lower compared to the SWV of BI-RADS 4b and 4c lesions (p = 0.00). In qualitative evaluation, pattern 1 only defined benign lesions, and a negative predictive value (NPV) of 100% was obtained. Using quantitative, qualitative and combined methods, the Likelihood ratios was determined to be 1.81, 2.8 and 4.7 respectively. In addition to the ultrasound examination of BI-RADS 4 lesions, the addition of combined elastography assessment increases the accuracy of BI-RADS. BI-RADS 4a lesions can be followed in a similar way as BI-RADS 3 lesions.Article Use of Virtual Touch Tissue Quantification Elastography Technique in Fetal Lung Maturation(Lippincott Williams & Wilkins, 2023) Arslan, Harun; Kucukbas, Gokce Naz; Turkoglu, Saim; Akdemir, Zulkuf; Yokus, Adem; Gunduz, Ali Mahir; Sahin, Hanim GulerThis study is an analysis of fetal lung stiffness by virtual touch tissue quantification (VTTQ) elastography to predict fetal lung maturation. Evaluation of fetal lungs was first performed in B mode, and fetal lungs were analyzed at 3 different periods at third trimester in each pregnant woman, at 28 to 31, 32 to 36, and 37 to 41 weeks. Fetal lung elastography was performed at regions with the least acoustic shadow and far from ribs and heart. Each fetal lung assessment were done by taking mean lung stiffness obtained by measuring stiffness of both left and right fetal lungs. T test analysis showed no significant difference in fetal lung stiffness between male and female fetuses among 3 gestational periods. Analysis of variance was performed to evaluate fetal lung stiffness of the fetuses at 3 different gestational periods (28-31, 32-36, and 37-41 weeks). This analysis showed significant difference (P < 0.01). Duncan multiple comparison analysis did not show significant difference in fetal lung stiffness between 28 and 31 weeks and 32 and 36 weeks, whereas fetal lung stiffness of fetuses at 37 to 41 weeks were significantly greater (P < 0.01). This study is first step to analyze fetal lung maturation noninvasively using VTTQ elastography technique by measuring fetal lung stiffness.