Tıp Fakültesi / Faculty of Medicine
Permanent URI for this collectionhttps://hdl.handle.net/11727/1403
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Item Magnetic Resonance Tagging for Diagnosis of Focal Hypertrophic Cardiomyopathy in A Child(2015) Coban, Gokcen; Yildirim, Muge Afsar; Donmez, Fuldem Yildirim; Tarhan, Nefise Cagla; Erdogan, Ilkay; Coskun, Mehmet; 0000-0001-5630-022X; 0000-0001-6887-3033; 0000-0003-4502-106X; 0000-0002-4010-2883; 0000-0001-9877-7106; 26012424; AAM-4120-2021; AAJ-2305-2021; ABB-2220-2021; AAE-5528-2021; P-7533-2014Magnetic resonance imaging has become an important diagnostic tool in the differential diagnosis of lesions for evaluation of cardiovascular disorders. In magnetic resonance tagging (MRt), tissue elements are magnetically labeled so that their positions can be tracked as a function of time. Thus, MRt evaluates heart wall motion both qualitatively and quantitatively. We present herein the case of a 12-year-old boy who had chest pain, dyspnea on effort and murmur. On cardiac computed tomography, there was focal thickening of the left ventricular posterior wall, similar to a mass. MRt indicated active displacement and deformation of the tags at the level of the hypertrophic myocardium during systole, as with normal myocardium. Thus, the tagged images supported the diagnosis of focal hypertrophic cardiomyopathy (HCM). In view of these results, MRt should be considered as a useful technique for differentiating between a mass-like focal lesion such as neoplasm and HCM.Item Diaphragmatic Hernia After Pediatric Liver Transplant(2015) Kirnap, Mahir; Akdur, Aydincan; Ozcay, Figen; Soy, Ebru; Coskun, Mehmet; Moray, Gokhan; Haberal, Mehmet; 0000-0002-3462-7632; 0000-0002-8726-3369; 0000-0003-2498-7287; 0000-0002-5214-516X; 0000-0001-5630-022X; 0000-0002-0993-9917; 26450470; AAJ-8097-2021; AAA-3068-2021; AAE-1041-2021; ABG-5684-2020; AAM-4120-2021; AAC-5566-2019; AAH-9198-2019Diaphragmatic hernia is an unusual complication after pediatric liver transplant. Nearly half of bowel obstruction cases, which require surgical intervention in liver transplant patients, are caused by diaphragmatic hernia. The smaller patients are at risk for higher rates of diaphragmatic complication after pediatric liver transplant, but diaphragmatic hernia has not been reported as a unique occurrence. Here, we report 3 cases of diaphragmatic hernia after liver transplant and discuss the possible contributing factors. Diaphragmatic hernia should nevertheless be added to the list of potential complications after liver transplant in the pediatric population. Pediatric transplant physicians and surgeons should be aware of this complication so that it is recognized promptly in both acute and nonacute settings and appropriate action is taken.Item Stereotactic Ablative Body Radiotherapy as a Bridge to Liver Transplant for Hepatocellular Carcinoma: Preliminary Results of Baskent University Experience(2022) Yavas, Guler; Soy, Ebru Hatice Ayvazoglu; Coskun, Mehmet; Onal, Cem; Boyvat, Fatih; Haberal, Mehmet; https://orcid.org/0000-0002-3462-7632; 35384806; HOC-5611-2023; AAJ-8097-2021Objectives: Hepatocellular carcinoma is the most common primary liver tumor, with curative treatment options being liver transplant and resection. However, approximately 20% to 30% of patients have substantial disease progression while awaiting transplant. Here, we report our initial experience on stereotactic ablative body radiotherapy as a bridge to liver transplant for patients with hepatocellular carcinoma. Materials and Methods: Seven patients with 9 lesions received stereotactic ablative body radiotherapy as a bridge treatment to transplant. All patients underwent radiofrequency ablation, transcatheter arterial chemoembolization, or hepatic resection before stereotactic ablative body radiotherapy. Magnetic resonance imaging was used to evaluate radiographic responses 1 month later. Results: Median age of patients was 65 years (range, 63-71 years), median stereotactic ablative body radiotherapy dose was 45 Gy (range, 30-54 Gy; delivered in 3-5 fractions), and median tumor diameter was 17 mm (range, 12-30 mm). Before stereotactic ablative body radiotherapy, all patients underwent liver-directed therapies, including transcatheter arterial chemoembolization for 3 lesions, transcatheter arterial chemoembolization and radiofrequency ablation for 4 lesions, surgical resection for 1 lesion, and surgical resection plus transcatheter arterial chemoembolization for the remaining lesion. Patients showed no evidence of gastrointestinal toxicity or radiation-induced liver disease. Acute toxicity was negligible; all patients completed the treatment course. One month after stereotactic ablative body radiotherapy administration, response rates were assessed with magnetic resonance imaging, with complete responses obtained in 5 lesions (55.5%), partial responses for 2 lesions, and stable disease for 2 lesions. No disease progression was shown following stereotactic ablative body radiotherapy application. Conclusions: Stereotactic ablative body radiotherapy is an effective, safe, and tolerable bridging therapy option. Although we observed an early response after treatment, exact response rates will not be known for at least 3 months following stereotactic ablative body radiotherapy. Thus, our findings should be confirmed through additional prospective studies with longer follow-up.Item Hepatocellular Carcinoma in the Cirrhotic Liver: Evaluation Using Computed Tomography and Magnetic Resonance Imaging(2017) Coskun, Mehmet; 0000-0001-5630-022X; 28301997; AAM-4120-2021Hepatocellular carcinoma is the fifth most common tumor in patients worldwide and the third most common cause of cancer-related death, after lung and stomach cancer. Cirrhosis of the liver is the strongest predisposing factor for hepatocellular carcinoma, with approximately 80% of cases of hepatocellular car-cinoma developing in a cirrhotic liver. The annual incidence of hepatocellular carcinoma is 2.0% to 6.6% in patients with cirrhosis compared with 0.4% in patients without cirrhosis. The 5-year survival rates of patients undergoing curative therapies for hepato cellular carcinoma, including liver transplant, hepatic resection, and percutaneous ablative techniques, range between 40% and 75%. Orthotropic liver transplant offers the prima facie cure for both hepatocellular carcinoma and liver cirrhosis. In hepatocellular carcinoma confined to the liver without macrovascular invasion, patients with a single tumor <= 5 cm or up to 3 tumors <= 3 cm each had a 5-year survival rate of 75% and a disease-free survival rate of 83%. In the adult population, liver transplant for hepatocellular carcinoma yields good results for patients whose tumor masses do not exceed the Milan criteria. The diagnosis of hepatocellular carcinoma using imaging tests has had a substantial impact on transplant decisions. Radiologists should be aware of this responsibility and exercise the utmost scrutiny before making a diagnosis of hepatocellular carcinoma. Erroneous diagnosis of hepatocellular carcinoma based on imaging tests could deny deserving patients the opportunity of a life-saving liver transplant and result in unnecessary liver transplants for others. Contrast-enhanced magnetic resonance imaging and helical computed tomography are the best imaging techniques currently available for the noninvasive diagnosis of hepatocellular carci noma. With techno-logical advances in hardware and software, diffusion-weighted imaging can be readily applied to the liver with resulting improved image quality.Item Coronary Artery Disease Detected by Coronary Computed Tomography Angiography is Associated with Red Cell Distribution Width(2016) Karacaglar, Emir; Bal, Ugur; Hasirci, Senem; Yilmaz, Mustafa; Doganozu, Ersin; Coskun, Mehmet; Atar, Ilyas; Yildirir, Aylin; Muderrisoglu, Haldun; 0000-0002-2538-1642; 0000-0002-9446-2518; 0000-0002-8342-679X; 0000-0002-2557-9579; 0000-0001-8750-5287; 0000-0002-9635-6313; 27774965; ABI-6723-2020; AAK-4322-2021; AAK-7805-2021; S-6973-2016; A-4947-2018; AAG-8233-2020Objective: Increased red blood cell distribution width (RDW) is associated with severity of coronary artery disease (CAD). The aim of the present study was to retrospectively evaluate the relationship between CAD detected by coronary computed tomography angiography (CCTA) and RDW. Methods: Records of 291 patients who underwent 16-slice CCTA due to the presence of angina-like chest pain were retrospectively evaluated. Exclusion criteria were applied. Clinical characteristics, risk factors for CAD, and RDW values on CCTA were noted. Results: RDW levels in patients with CAD were significantly higher than in those with normal coronary arteries (NCAs) (15.50 +/- 1.57 compared to 14.80 +/- 1.41, p=0.001). Diabetes mellitus, hypertension, and history of smoking were significantly more common in the CAD group (p=0.018, p=0.007, and p=0.013, respectively). On multivariate logistic regression analysis, RDW (p=0.009 [odds ratio (OR): 1.352; 95% confidence interval (CI): 1.081-1.683]), age (p<0.001 [OR: 1.063; 95% CI 1.031-1.090]), and history of smoking (p=0.003 [OR: 2.672; 95% CI: 1.360-5.232]) were shown to be independent predictors for CAD detected by CCTA. Conclusion: The present results suggest that higher RDW levels are independently associated with presence of CAD detected by CCTA in patients without known CAD. Further studies are warranted to clarify the exact role of RDW in risk stratification.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 Acute Pancreatitis Caused by Primary Pancreatic Lymphoma in A Geriatric Patient with Sarcoidosis: Report of A Complex Case(2017) Ozer Etik, Digdem; Suna, Nuretdin; Tepeoglu, Merih; Coskun, Mehmet; Selcuk, Haldun; 0000-0002-4724-0728; 0000-0001-6234-7788; 0000-0002-9894-8005; 0000-0001-5630-022X; 0000-0002-8445-6413; AAJ-4707-2021; AAI-8822-2021; AAK-5222-2021; AAM-4120-2021; AAJ-6976-2021The purpose of reporting this case is to raise the awareness of the rapid worsening clinical presentation of acute pancreatitis in an older patient, unexpected encounter with pancreatic lymphoma, and sarcoidosis-lymphoma syndrome. An 80-year-old woman was diagnosed with sarcoidosis 16 years ago. Following recent hospitalization because of acute pancreatitis, non-obstructive and non-invasive pancreatic mass was found on radiological images. Histopathology confirmed the mass to be diffuse large B-cell lymphoma. We report this case because of its complicated the etiology of acute pancreatitis in an older patient, presentation of pancreatic lymphoma, and immune pathogenesis of sarcoidosis-lymphoma syndrome.Item Subcutaneous and Muscular Metastasis of Pancreatic Adenocarcinoma(2017) Haberal, Kemal Murat; Donmez, Fuldem Yildirim; Ayva, Ebru Sebnem; Coskun, Mehmet; 0000-0002-8211-4065; 0000-0003-4502-106X; 0000-0002-2280-8778; R-9398-2019; AAE-5528-2021; AAK-1967-2021Soft tissue metastasis from pancreatic cancer is a very rare entity. We reported a case presenting with multiorgan and soft tissue metastasis on computed tomography. Computed tomography scan showed a hypovascular mass in the pancreatic body and tail. Computed tomography guided biopsy from muscle metastases diagnosed an undifferentiated tumor. Based on clinical, radiological and pathological correlation, the diagnosis of pancreatic adenocarcinoma was established. There are few reported cases of skeletal muscle metastasis from pancreatic cancer. Immunohistochemical staining and imaging findings should be used together to determine the correct diagnosis.Item Virtual contrast enhancement for CT scans of abdomen and pelvis(2022) Liu, Jingya; Tian, Yingli; Duzgol, Cihan; Akin, Oguz; Agildere, A. Muhtesem; Haberal, K. Murat; Coskun, Mehmet; 0000-0002-8211-4065; 35914340; R-9398-2019Contrast agents are commonly used to highlight blood vessels, organs, and other structures in magnetic resonance imaging (MRI) and computed tomography (CT) scans. However, these agents may cause allergic reactions or nephrotoxicity, limiting their use in patients with kidney dysfunctions. In this paper, we propose a generative adversarial network (GAN) based framework to automatically synthesize contrast-enhanced CTs directly from the non-contrast CTs in the abdomen and pelvis region. The respiratory and peristaltic motion can affect the pixel-level mapping of contrast-enhanced learning, which makes this task more challenging than other body parts. A perceptual loss is introduced to compare high-level semantic differences of the enhancement areas between the virtual contrast-enhanced and actual contrast-enhanced CT images. Furthermore, to accurately synthesize the intensity details as well as remain texture structures of CT images, a dual-path training schema is proposed to learn the texture and structure features simultaneously. Experiment results on three contrast phases (i.e. arterial, portal, and delayed phase) show the potential to synthesize virtual contrast-enhanced CTs directly from non-contrast CTs of the abdomen and pelvis for clinical evaluation.Item Use of Computed Tomography Volumetry to Assess Liver Weight in Patients With Cirrhosis During Evaluation Before Living-Donor Liver Transplant(2021) Haberal, Kemal Murat; Rahatli, Feride Kural; Turnaoglu, Hale; Ozgun, Gonca; Coskun, Mehmet; 0000-0002-8211-4065; 0000-0002-4226-4034; 0000-0002-0781-0036; 0000-0001-5630-022X; 30398100; R-9398-2019; AAL-9808-2021; AAK-8242-2021; AAM-4120-2021Objectives: Computed tomography liver volumetry has been widely used to detect total and segmental liver volume in living-donor liver transplantation. However, use of this technique to evaluate the cirrhotic liver remains unclear. In this study, we evaluated the accuracy of freehand computed tomography volumetry to assess total liver volume by comparing weights of total hepatectomy specimens in patients with cirrhosis. For our analyses, we considered the density of a cirrhotic liver to be 1.1 kg/L. Materials and Methods: Liver volume was measured using a freehand computed tomography technique in 52 patients with cirrhosis from different causes and who had no solid lesions before transplant. Measurements were made with a 16-slice multidetector computed tomography scanner (Siemens Somatom Sensation 16, Erlangen, Germany). For volumetric measurements, 10-mm-thick slices with 10-mm reconstruction intervals were preferred. Total hepatectomy weights of explant livers and computed tomography volumetry data were compared. Results: We excluded 3 cirrhotic patients with Budd-Chiari syndrome due to wide variations in scatterplot results. In the 49 patients included in the final analyses, average estimated liver volume by computed tomography was 721 +/- 398 mL and actual cirrhotic liver weight was 727.8 +/- 415 g. No significant differences were shown between these measurements. A simple regression analysis used to analyze correlations between estimated liver volume by computed tomography and real cirrhotic liver weight showed correlation of 0.957 (P < .001). When computed tomography liver volumetry as the independent variable and cirrhotic liver weight as dependent variable were considered, regression analyses showed R-2 = 0.915. Conclusions: Freehand computed tomography liver volumetry can be confidently used to evaluate liver volume in cirrhotic liver patients similar to use of this technique to estimate actual weights in normal livers. This technique can also be valuable during pretransplant and liver resection evaluations to ensure a more successful outcome.