Objectives: The aim of this study was to investigate the relationship between pathological classification of parotid gland tumors and conventional magnetic resonance imaging (MRI) – diffusion weighted imaging (DWI) findings and also contribute the possible effect of apparent diffusion coefficient (ADC) to diagnosis. Methods: Sixty patients with parotid masses diagnosed using histopathology and/or cytology were enrolled in this retrospective study. All patients were evaluated using a 1.5 Tesla MRI. Demographic features, conventional MRI findings, and ADC values (mean, minimum, maximum, and relative) were recorded. MRI findings and ADC values were compared between benign-malignant groups and pleomorphic adenoma versus Warthin’s tumor groups. Results: Sixty tumors (48 benign, 12 malignant) were evaluated in a total of 60 patients (39 males, 21 females). The mean age was 59 (±14, 18–86) years old; the mean lesion size was 26 (±10, 11–61) mm. On the texture of conventional MRI, T2 dominantly hyperintense/with hypointensity signal was seen in 87% of pleomorphic adenomas and T2 dominantly hypointense/with hyperintesity signal was encountered in 64% of all Warthin’s tumors. Seven (28%) Warthin’s tumors were misdiagnosed as pleomorphic adenomas and two others (8%) as malignant tumors. The commonly used mean ADC value was 1.6 ± 0.6 × 10–3 mm2 sec−1 for benign tumors, 0.8 ± 0.3 × 10–3 mm2 sec−1 for malign tumors, 1 (0.9–1.8) × 10–3 mm2 sec−1 for Warthin’s tumors, and 1.9 ± 0.3 × 10–3 mm2 sec−1 for pleomorphic adenomas. There was a statistically significant difference in ADC values between benign-malignant tumors and pleomorphic adenomas-Warthin’s tumors. Conclusions: Warthin’s tumor may occasionally be misdiagnosed as pleomorphic adenoma and malignant tumor because of variable morphologic features. In addition to benign-malignant differentiation, the added ADC measurement may also be useful for differentiating Warthin’s tumors from pleomorphic adenomas.

Introduction:The purpose of this study was to determine the primary patency rate of endovascular interventions in hemodialysis patients who had central venous stenosis or occlusion. Material and methods: Twenty-seven hemodialysis patients, who underwent endovascular intervention between January 2013 and January 2018 for central venous stenosis or total obstruction, were included in the study. Endovascular interventions consisted of percutaneous transluminal angioplasty (PTA) or stent implantation. Primary patency rate of endovascular intervention at the sixth and twelfth months were evaluated. Results: Stent implantation and PTA were used in 5 patients and 22 patients, respectively. Fourteen patients had stenosis and 13 patients had occlusion. The total procedural success rate was 81%, 86% in stenosis and 77% in occlusion. There was no procedure-related complication. The primary patency for PTA at 6 and 12 months were 40% and 10%, respectively. For stent implantation, primary patency rate at 6 and 12 months was 70% and 30%, respectively. Conclusion: Endovascular interventions for central venous stenosis and occlusion are safe, with low rates of technical failure and they can be first-line treatment for central venous stenosis or occlusion in hemodialysis patients.

Objective:To investigate the association between the morphologic and kinetic results obtained with the dynamic contrast-enhanced magnetic resonance imaging (MRI), and the apparent diffusion coefficient (ADC) values obtained using diffusion-weighted imaging (DWI) in breast cancer with the histopathologic subtypes of tumors. Material and Methods: The MRI results of 271 breast lesions of 258 patients were retrospectively evaluated. Lesion morphology and contrast-enhancement characteristics were evaluated using conventional MRI, and ADC measurements were performed with DWI. Results: An association was detected between regular margins in the masses, the presence of intratumoral necrosis, and annular contrast enhancement with triple-negative type (TN), spiculated margin luminal A type. Higher histological grade was mostly detected in TN (45.7%), and human epidermal growth factor receptor 2 positive (HER2+) tumors (47.1%) (p<0.001). The mean ADC value was measured as 1001x10 -6 mm 2 /second. No significant difference was detected in molecular subtypes considering the ADC values (p=0.396). No correlation was detected between the Ki-67 proliferation index and the mean ADC values (p=0.207). Conclusion: Although the morphological results of dynamic contrast-enhanced breast MRI indicated particular molecular subtypes, it may be suggested that the ADC values obtained using DWI were not decisive in identifying molecular subtypes.

The aim of this study was to determine the relationship between histopathological results and conventional magnetic resonance imaging (MRI), diffusion-weighted imaging findings of parotid gland tumors and the possible contribution of apparent diffusion coefficient (ADC) to diagnosis. Material and Methods: Sixty patients with parotid masses diagnosed using histopathology and/or cytology were enrolled in this retrospective study. All patients were evaluated using a 1.5 Tesla MRI. Demographic features, conventional MRI findings, and ADC values (mean, minimum, maximum, and relative) were recorded. MRI findings and ADC values were compared between benign-malignant groups and pleomorphic adenoma versus Warthin's tumor groups. Results: Sixty tumors (48 benign, 12 malignant) were evaluated in a total of 60 patients (39 males, 21 females). The mean age was 59 (±14, 18-86) years; the mean lesion size was 26 (±10, 11-61) mm. On the texture of conventional MRI, T2 dominantly hyperintense/with hypointensity signal was seen in 87% of pleomorphic adenomas and T2 dominantly hypointense/with hyperintesity signal was encountered in 64% of all Warthin's tumors. Seven (28%) Warthin's tumors were misdiagnosed as pleomorphic adenomas and two others (8%) as malignant tumors. Commonly used mean ADC value was 1.6±0.6×10−3 mm2/s for benign tumors, 0.8±0.3×10-3 mm2/s for malign tumors, 1 (0.9-1.8)×10-3 mm2/s for Warthin's tumors, and 1.9±0.3×10-3 mm2/s for pleomorphic adenomas. There was a statistically significant difference in ADC values between benign-malignant tumors and pleomorphic adenomas-Warthin's tumors. Conclusion: Warthin's tumor may occasionally be misdiagnosed as pleomorphic adenoma and malignant tumor because of variable morphologic features. In addition to benign-malignant differentiation, the added ADC measurement may also be useful for differentiating Warthin's tumors from pleomorphic adenomas.