Tıp Fakültesi / Faculty of Medicine
Permanent URI for this collectionhttps://hdl.handle.net/11727/1403
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Item Diagnostic Value of T2*-Weighted Gradient-Echo MRI for Segmental Evaluation in Cerebral Venous Sinus Thrombosis(2015) Altinkaya, Naime; Demir, Senay; Alkan, Ozlem; Tan, Meliha; 0000-0002-4209-9075; 0000-0003-1348-8167; 0000-0001-7526-3460; 25148696; AAK-9310-2021; AAM-5169-2021; AAM-4169-2021Objective: We evaluated the diagnostic value of gradient-echo (GRE) imaging in patients with "cerebral venous and sinus thrombosis" (CVST). Materials and Methods: In total, 130 thrombosed venous segment signal intensities in 45 patients with CVST were analyzed retrospectively using magnetic resonance imaging and magnetic resonance venography. Results: The T2* GRE sequence had a diagnostic value for detecting acute and subacute superior sagittal sinus (SSS) thrombosis and thrombosis of the deep veins (DVs), and cortical veins (CVs; P<.05). Conclusions: The T2* GRE sequence had a high diagnostic value for detecting both acute and subacute SSS, DV, and CV thromboses. (C) 2015 Elsevier Inc. All rights reserved.Item Uterine Perforation During 3-Dimensional Image-Guided Brachytherapy in Patients With Cervical Cancer Baskent University Experience(2014) Onal, Cem; Guler, Ozan Cem; Dolek, Yemliha; Erbay, Gurcan; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0002-1706-8680; 24407583; HOC-5611-2023; AAC-5654-2020; AAK-5370-2021Objectives This study aimed to determine the incidence and characteristics of uterine perforation at our department using 3-dimensional computed tomography (CT)-based brachytherapy (BRT). The characteristics of the patients presenting with perforation and impact of the perforation on the treatment course were also analyzed. Materials and Methods The clinical and radiologic data of 200 patients with biopsy-proven cervical cancer treated using CT-based BRT were retrospectively evaluated. All patients had undergone tandem-based intracavitary BRT, and 67 patients had undergone magnetic resonance imaging (MRI) before BRT. Results Of the 200 patients, 17 (8.5%) had uterine perforation. Of the 626 applications with CT images, 30 (4.8%) resulted in uterine perforation. The median age of patients with perforation was higher (68 years; range, 44-89 years) than that of the patients without perforation (59 years; range, 21-87 years), and the mean (SD) tumor size at diagnosis was larger in patients with perforation (7.0 [1.5] cm) than in patients without perforation (5.0 [1.5] cm). The most frequent perforation site was the posterior uterine wall (8 patients), followed by the fundus (5 patients) and anterior wall (4 patients). Of the 7 patients with a retroverted uterus, 4 had uterine perforation during BRT. In 67 patients with MRI delivered before BRT, only 3 (4%) had uterine perforation, and 2 of the 3 patients with uterine perforation had a retroverted uterus. However, of the 133 patients with no MRI evaluation before BRT, 14 (11%) had uterine perforation. No life-threatening complications or signs of intraperitoneal tumor cell seeding were observed. Conclusions Older age, larger tumors, a retroverted uterus, and a stenotic cervical os were all predisposing factors for uterine perforation during BRT. Preoperative MRI is a feasible and safe method to decrease the risks of uterine perforation and could be used preoperatively in centers where intraoperative ultrasonography is not used in routine practice.Item Utility of Diffusion-Weighted MRI to Detect Changes in Liver Diffusion in Benign and Malignant Distal Bile Duct Obstruction: The Influence of Choice of b-Values(2016) Karan, Belgin; Erbay, Gurcan; Koc, Zafer; Pourbagher, Aysin; Yildirim, Sedat; Agildere, Ahmet Muhtesem; 0000-0003-0987-1980; 0000-0002-5735-4315; 0000-0002-1706-8680; 0000-0003-4223-7017; 27592163; S-8384-2016; AAF-4610-2019; AAK-5370-2021; AAB-5802-2020Purpose: The study sought to evaluate the potential of diffusion-weighted magnetic resonance imaging to detect changes in liver diffusion in benign and malignant distal bile duct obstruction and to investigate the effect of the choice of b-values on apparent diffusion coefficient (ADC). Methods: Diffusion-weighted imaging was acquired with b-values of 200, 600, 800, and 1000 s/mm(2). ADC values were obtained in 4 segments of the liver. The mean ADC values of 16 patients with malignant distal bile duct obstruction, 14 patients with benign distal bile duct obstruction, and a control group of 16 healthy patients were compared. Results: Mean ADC values for 4 liver segments were lower in the malignant obstruction group than in the benign obstruction and control groups using b = 200 s/mm(2) (P < .05). Mean ADC values of the left lobe medial and lateral segments were lower in the malignant obstruction group than in the benign obstructive and control groups using b = 600 s/mm2 (P < .05). Mean ADC values of the right lobe posterior segment were lower in the malignant and benign obstruction groups than in the control group using b = 1000 s/mm(2) (P < .05). Using b = 800 s/mm(2), ADC values of all 4 liver segments in each group were not significantly different (P > .05). There were no correlations between the ADC values of liver segments and liver function tests. Conclusion: Measurement of ADC shows good potential for detecting changes in liver diffusion in patients with distal bile duct obstruction. Calculated ADC values were affected by the choice of b-values.Item Comparison of Three-Dimensional Ultrasound and Magnetic Resonance Imaging Diagnosis in Surgically Proven Mullerian Duct Anomaly Cases(2016) Ergenoglu, Ahmet Mete; Sahin, Cagdas; Simsek, Deniz; Akdemir, Ali; Yeniel, Ahmet Ozgur; Yerli, Hasan; Sendag, Fatih; https://orcid.org/0000-0003-2463-1758; 26699099; AAK-9572-2021Objective: To determine and compare the diagnostic accuracy of 3-dimensional ultrasound (3D US) and magnetic resonance imagining (MRI) in patients with surgically diagnosed Mullerian duct anomaly (MDA). Study design: Charts of patients with MDA were retrospectively evaluated. Patients who underwent both laparoscopic and hysteroscopic surgery and had 3D US and MRI examinations were included in the study. The diagnoses achieved via 3D US and MRI were compared with the surgical diagnoses to determine the diagnostic accuracy of these imagining techniques. Results: Twenty-nine patients were included in the study. Three-dimensional ultrasound detected 28 out of 29 (96%) patients correctly. Only one patient was diagnosed with a uterine septum instead of uterine arcuatus. Magnetic resonance imaging detected 23 out of 29 patients correctly (79%). The Kappa indexes of the 3D US and MRI were 0.896 and 0.592, respectively. Conclusion: Our results indicate that 3D US has a higher diagnostic accuracy level than MRI in evaluating MDA, especially when used in experienced hands. However, additional, well-designed studies are needed to better compare the diagnostic accuracy of the 3D US and MRI. Crown Copyright (C) 2015 Published by Elsevier Ireland Ltd. All rights reserved.Item A Comparison of Magnetic Resonance Imaging and Electroneuromyography for Denervated Muscle Diagnosis(2017) Tepeli, Betul; Karatas, Metin; Coskun, Mehmet; Yemisci, Oya Umit; https://orcid.org/0000-0002-0501-5127; 27893494; AAJ-8820-2021Purpose: The aim of this study was to evaluate the diagnostic value of magnetic resonance imaging (MRI) for muscle denervation due to focal lesions of the median nerve and to compare electrophysiological findings with MRI findings. Methods: Twenty-six patients with electrophysiological studies diagnosed for focal lesions of the median nerve were included in this study. Electrophysiological studies and MRI were conducted on 34 patients' hands. Patients' hands were divided into two groups based on edema findings revealed by the MRI: group 1 (edema-negative group; n = 24) and group 2 (edema-positive group; n = 10). Results: Positive correlations were found between the existence of edema in MRI and fibrillation, positive sharp waves, denervation, and the level of reduced recruitment pattern. In median nerve conduction studies, amplitude of compound muscle action potential and palm-to-wrist segment mixed-nerve action potentials were significantly lower, and also the third-digit wrist sensory nerve conduction velocity and mixed-nerve palm-wrist conduction velocity were significantly slower in group 2. Conclusions: For muscle denervation resulting from median nerve lesions, MRI findings correlated with electrophysiological findings; further study is required for the use of MRI.Item Utility of Diffusion Weighted Magnetic Resonance Imaging with Multiple B Values in Evaluation of Pancreatic Malignant and Benign Lesions and Pancreatitis(2018) Karadeli, Elif; Erbay, Gurcan; Parlakgumus, Alper; Koc, Zafer; https://orcid.org/0000-0002-0352-8818; https://orcid.org/0000-0002-1706-8680; https://orcid.org/0000-0003-0987-1980; 29394967; AAK-5399-2021; AAK-5370-2021; S-8384-2016Objective: To determine the feasibility of diffusion-weighted imaging in evaluation of pancreatic lesions and in differentiation of benign from malignant lesions. Study Design: Descriptive study. Place and Duration of Study: Baskent University Adana Teaching and Research Center, Adana, Turkey, between September 2013 and May 2015. Methodology: Forty-three lesions [pancreas adenocarcinoma (n = 25)], pancreatitis (n = 10), benign lesion (n = 8)] were utilized with diffusion-weighted magnetic resonance imaging with multiple b-values. Different ADC maps of diffusion weighted images by using b-values were acquired. Results: The median ADC at all b values for malignant lesions was significantly different from that for benign lesions (p < 0.001). When ADCs at all b values were compared between benign lesions/normal parenchyma and malignant lesions/normal parenchyma, there was a significant statistical difference in all b values between benign and malignant lesions except at b 50 and b 200 (p<0.05). The lesion/normal parenchyma ADC ratio for b 600 value (AUC=0.804) was more effective than the lesion ADC for b 600 value (AUC=0.766) in differentiation of benign and malignant lesions. The specificity and sensitivity of the lesion/normal parenchyma ADC ratio were higher than those of ADC values of lesions. When the ADC was compared between benign lesions and pancreatitis, a significant difference was found at all b values (p<0.001). There was not a statistically significant difference between the ADC for pancreatitis and that for malignant lesions at any b value combinations (p>0.05). Conclusion: Diffusion-weighted magnetic resonance images can be helpful in differentiation of pancreatic carcinoma and benign lesions. Lesion ADC / normal parenchyma ADC ratios are more important than lesion ADC values in assessment of pancreatic lesions.Item Can Breast Magnetic Resonance Imaging Prevent Biopsy or Change the Management of BI-RADS (R) Category 4 Breast Lesions?(2018) Turnaoglu, Hale; Ozturk, Emine; Yucesoy, Cuneyt; Teber, Mehmet Akif; Turan, Aynur; Ozbalci, Aysu Basak; Seker, Ebru Gaye; Onal, Binnur; Hekimoglu, Baki; 0000-0002-0781-0036; AAK-8242-2021The BI-RADS (R) category 4 includes suspicious breast lesions which requires biopsy. The aim of this study is to investigate the contribution of breast magnetic resonance imaging to the management of BI-RADS (R) category 4 breast lesions detected by mammography and/or ultrasonography. Thirty-four lesions classified as BI-RADS (R) category 4A, 4B, or 4C by conventional methods were evaluated with magnetic resonance imaging. All lesions were coded by using the American College of Radiology BI-RADS (R) lexicon. Each lesion was verified with the result of pathology. Lesions were evaluated as BI-RADS (R) category 1 in 1 patient (2.9%), category 3 (20.6%) in 7 patients, category 4 in 25 patients (73.6%), and category 5 in 1 patient (2.9%) with breast magnetic resonance imaging. Only the BI-RADS (R) 4A lesion categories were changed by breast magnetic resonance imaging, and these lesions were pathologically diagnosed as benign. The negative predictive value of breast MRI for BI-RADS (R) category 4A lesions was calculated as 100%. In all BI-RADS (R) category 4 lesions, pathologically 4 lesions found to be high risk and 3 lesions found to be malignant. The sensitivity, specificity, positive predictive, and negative predictive value of breast magnetic resonance imaging in BI-RADS (R) category 4 lesions were calculated as 100, 29.6, 26.9, and 100%, respectively. The area under the ROC curve was calculated 0.648. Breast magnetic resonance imaging is promising to be used as a problem-solving modality in BI-RADS (R) category 4A breast lesions.Item The prognostic value of mean apparent diffusion coefficient measured with diffusion-weighted magnetic resonance image in patients with prostate cancer treated with definitive radiotherapy(2022) Onal, Cem; Erbay, Gurcan; Guler, Ozan Cem; Oymak, Ezgi; 35753556Purpose: To assess the correlation between initial tumor apparent diffusion coefficient (ADC) values and clinicopathological parameters in prostate cancer (PCa) patients treated with definitive radiotherapy (RT). Additionally, the prognostic factors for freedom from biochemical failure (FFBF) and progressionfree survival (PFS) in this patient cohort were analyzed. Materials and methods: The clinical data of 503 patients with biopsy-confirmed PCa were evaluated retrospectively. All patients had clearly evident tumors on diffusion-weighted magnetic resonance imaging (DW-MRI) for ADC values. Univariable and multivariable analyses were used to determine prognostic factors for FFBF and PFS. Results: The median follow-up was 72.9 months. The 5-year FFBF and PFS rates were 93.2% and 86.2%, respectively. Significantly lower ADC values were found in patients with a high PSA level; advanced clinical stage; higher ISUP score, and higher risk group than their counterparts. Receiver operating characteristic (ROC) curve analysis revealed an ADC cut-off value of 0.737 x 10-3 mm2/sec for tumor recurrence. Patients who progressed had a lower mean ADC value than those who did not (0.712 +/- 0.158 vs. 1.365 +/- 0. 227 x 10-3 mm2/sec; p < 0.001). There was a significant difference in 5-year FFBF (96.3% vs. 90%; p < 0.001) and PFS rates (83.8% vs. 73.5%; p = 0.002) between patients with higher and lower mean ADC values. The FFBF and PFS were found to be correlated with tumor ADC value and ISUP grades in multivariable analysis. Additionally, older age was found to be a significant predictor of worse PFS. Conclusions: Lower ADC values were found in patients with high-risk characteristics such as a high serum PSA level, stage or grade of tumor, or high-risk disease, implying that ADC values could be used to predict prognosis. Lower ADC values and higher ISUP grades were associated with an increased risk of BF and progression, implying that treatment intensification may be required in these patients. (c) 2022 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 173 (2022) 285-291Item Predictors of progression in primary progressive multiple sclerosis in a large Turkish cohort(2020) Vural, Atay; Derle, Eda; Sayat-Gurel, Guliz; Karabudak, Rana; Tuncer, Asli; 0000-0003-2122-1016; 31743849; AAI-8830-2021Background: Studies on the predictors of progression for primary progressive multiple sclerosis (PPMS) are limited and there is no information in the literature for populations outside Europe and North America. In this study, we aimed to identify predictors of progression in a large Turkish PPMS cohort. Methods: We analyzed a cohort of 157 PPMS patients to investigate the effect of age of onset, gender, onset symptoms, presence or absence of relapses, and baseline gadolinium-enhancing lesions on the rate of progression to EDSS6 by using Kaplan-Meier analysis and multivariate Cox regression. Results: Older age of onset and presence of spinal motor symptoms at onset were associated with a shorter time to EDSS6 and presence of supratentorial signs at onset was associated with a longer time to EDSS6 according to Kaplan-Meier analysis. These factors remained significant after multivariate Cox-regression analysis. Clinical relapses were present in 22.3% and gadolinium-enhancing lesions on baseline MRI were present in 28% of patients, but these factors were not predictive of time to EDSS6. Conclusion: We identified age of onset and symptom at onset as predictors of progression in Turkish PPMS patients. Presence of clinical relapses or baseline gadolinium-enhancing lesions did not affect PPMS progression rate.Item Is fetal magnetic resonance imaging indicated in patients with isolated ventriculomegaly?(2019) Durdag, Gulsen Dogan; Baran, Safak Yilmaz; Kalayci, Hakan; Alkan, Ozlem; 0000-0001-5874-7324; 31228676; ABF-6439-2020Objective: Ventriculomegaly is one of the most common anomalies encountered at obstetric ultrasound and it necessitates follow up. Fetal magnetic resonance imaging (MRI) can be used to confirm the ultrasound diagnose or to detect additional anomalies. Aim of this study is to assess follow up and management of fetal ventriculomegaly shown by ultrasound, and to evaluate additional diagnostic contribution of MRI. Study Design: This study was conducted retrospectively including 89 patients who had fetal MRI subsequent to ultrasound diagnose of ventriculomegaly in between 2011-2017. Medical records of patients were investigated and accompanying anomalies, congenital infection. chromosomal examination, degree and progression of ventriculomegaly, neonatal imaging and diagnose, and neurodevelopmental findings on follow up were evaluated. Patients were classified in two groups as isolated and nonisolated ventriculomegaly, and subgroups mild, moderate, severe were formed according to their findings. SPSS 23.0 programme was used for statistical analysis. Results: Ultrasound and following MRI was performed in a range of 18-35 th gestational weeks, diagnoses were isolated ventriculomegaly for 56 patients and nonisolated ventriculomegaly for 33 patients. Progression and neurodevelopmental delay was higher in severe nonisolated ventriculomegaly group. There was not significant contribution of MRI in the follow up of isolated ventriculomegaly (p < 0.001), and diagnostic imaging findings declined in neonatal period with proceeding normal neurodevelopment in 92.7% of patients followed with diagnosis of isolated ventriculomegaly. Conclusion: When isolated ventriculomegaly is detected, ultrasound performed by an experienced team is mostly sufficient. MRI can be used in suspicious cases or when ventriculomegaly progresses. (C) 2019 Elsevier B.V. All rights reserved.