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    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-9398-2019
    Contrast 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.
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    A case of primer angiosarcoma in a young woman: lessons from multi-modality imaging
    (2022) Coskun, Mehmet; Hasirci, Senem Has; Ozdemir, Handan; Coskun, Mehmet; Sezgin, Atilla; Muderrisoglu, I. Haldun; Sade, Leyla Elif; 0000-0002-7528-3557; X-8540-2019
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    17 Years Of Pediatric Liver Transplantation Experience For Cirrhosis And Hepatocellular Carcinoma
    (2022) Ozcay, Figen; Sezer, Oya Balci; Sarialioglu, Faik; Boyvat, Fatih; Coskun, Mehmet; Reyhan, Nihan Haberal; Haberal, Mehmet; https://orcid.org/0000-0002-3462-7632; AAJ-8097-2021
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    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-4120-2021
    Objectives: 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.
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    Prognostic Value of Magnetic Resonance Imaging in the Evaluation of Physical Therapy Outcomes in Patients with Adhesive Capsulitis
    (2021) Cosar, Sacide Nur Saracgil; Ozen, Selin; Coskun, Mehmet; Yemisci, Oya Umit; Kurtcebe, Ali Niyazi; 0000-0001-8306-463X; 0000-0002-7290-8558; 0000-0002-0501-5127; 34396065; AAF-1085-2021; ABC-1305-2020; AAJ-8820-2021
    Objectives: This study aims to investigate whether the treatment outcomes of patients with a clinical diagnosis of adhesive capsulitis (AC) and magnetic resonance imaging (MRI) findings consistent with AC undergoing physical therapy (PT) differs to those with AC in the absence of these MRI findings. Patients and methods: Between January 2012 and October 2012, a total of 30 patients (8 males, 22 females; mean age 55.6 +/- 12.1 years; range, 35 to 85 years) with a clinical diagnosis of AC underwent MRI of the index shoulder. The MRI scans were evaluated for findings associated with AC: intensity of the inferior glenohumeral ligament (IGHL) and rotator interval (RI). All patients received a total of 15 sessions of PT: hot pack, transcutaneous electrical nerve stimulation, ultrasound, and shoulder exercises. The patients were assessed for shoulder range of motion (ROM) using the Visual Analog Scale ( VAS) for shoulder pain, Quick Disabilities of the Arm Shoulder and Hand (Q-DASH), and Health Assessment Questionnaire (HAQ) prior to and following completion of PT. Results: Of the patients, 21 had no MRI findings consistent with AC (Group 1), nine patients had changes in the IGHL and/or RI characteristic of AC (Group 2). In both groups, there was a significant improvement in active and passive shoulder ROM and VAS scores for shoulder pain at rest (Group 1: p<0.001, Group 2: p=0.017) with movement (Group 1: p<0.001, Group 2: p=0.007) and at night (Group 1: p<0.001, Group 2: p=0.012) following PT. However, there was no significant inter-group difference in scores. Similar findings were recorded for Q-DASH and HAQ. Conclusion: Based on these study findings, the presence of characteristic MRI findings of AC with a clinical diagnosis do not predict clinical response to physical therapy.
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    Diagnostic importance of maximum intensity projection technique in the identification of small pulmonary nodules with computed tomography
    (2020) Guleryuz Kizil, Pinar; Hekimoglu, Koray; Coskun, Mehmet; Akcay, Sule; 0000-0002-0805-0841; 0000-0001-5630-022X; 0000-0002-8360-6459; 32755123; AAD-9097-2021; AAM-4120-2021; AAB-5175-2021
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    Diagnostic importance of maximum intensity projection technique in the identification of small pulmonary nodules with computed tomography
    (2020) Guleryuz Kizil, Pinar; Hekimoglu, Koray; Coskun, Mehmet; Akcay, Sule; 0000-0001-5630-022X; 0000-0002-0805-0841; 0000-0002-8360-6459; 32718138; AAM-4120-2021; AAD-9097-2021; AAB-5175-2021
    Introduction: In this retrospective study, the aim is to determine the sensitivity of maximum intensity projection (MIP) technique to 3 mm-thick axial sections in patients with small pulmonary nodules identified via examination using computed tomography (CT), and to identify whether this technique provides significant reduction in duration of nodule evaluation. Materials and Methods: A total of 69 patients (339 nodules) who underwent thoracic tomography due to various complaints and in whom pulmonary nodules were identified as a result of the examination were included in the study. Their axial sections that are 3 mm-thick and MIP sections obtained in the axial plane were evaluated by two different radiologists at different times by keeping time. the dimensions and evaluation times of the nodules were recorded separately for each method. Results: Evaluation compatibility between the radiologists was found to be 86.8% and it was considered to be perfectly compatible. Sensitivity of the 1st radiologist in the detection of nodules with MIP was 81.4%, whereas the sensitivity of the 2nd radiologist was 83.4%. In the evaluation for the reporting periods, when the duration of evaluation of MIP images were compared with the gold standard, a statistically significant reduction was found in the reporting times of both radiologists (p< 0.01). Conclusion: It was found that utilization of MIP images as an alternative method to detect pulmonary modules reduces the duration of evaluation significantly and provides the ability to detect nodules with high sensitivity. According to these data, MIP imaging may be preferred as an adjunct method in the evaluation of lung nodules as it provides fast and reliable information besides classical axial sections.
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    Liver and Kidney Transplant During a 6-Month Period in the COVID-19 Pandemic: A Single-Center Experience
    (2020) Akdur, Aydincan; Karakaya, Emre; Soy, Ebru H. Ayvazoglu; Karakayali, Feza Yarbug; Yildirim, Sedat; Torgay, Adnan; Sayin, Cihat Burak; Coskun, Mehmet; Moray, Gokhan; Haberal, Mehmet; 0000-0002-1874-947X; 0000-0002-6829-3300; 0000-0002-8726-3369; 0000-0002-0993-9917; 0000-0002-3462-7632; 0000-0002-5735-4315; 0000-0002-4879-7974; 0000-0003-2498-7287; 0000-0001-5630-022X; 33143601; AAB-3888-2021; AAJ-5221-2021; AAA-3068-2021; AAC-5566-2019; AAJ-8097-2021; AAF-4610-2019; AAD-5466-2021; AAE-1041-2021; AAM-4120-2021
    Objectives: With the declaration of COVID-19 as a pandemic, many studies have indicated that elective surgeries should be postponed. However, post-ponement of transplants may cause diseases to get worse and increase the number in wait lists. We believe that, with precautions, transplant does not pose a risk during pandemic. Here, we aimed to evaluate our transplant results, which we safely performed during a 6-month pandemic period. Materials and Methods: Until September 2020, 3140 kidney and 667 liver transplants have been performed in our centers. We evaluated 38 kidney transplants and 9 liver transplants procedures performed during the pandemic (March 1 to September 2, 2020). Recipient and donor candidates were screened for COVID-19 with polymerase chain reaction and thoracic computed tomography. All recipients had routine immunosuppressive protocol. During hospitalization at our COVID-19-free transplant facility, we restricted the interactions during multidisciplinary rounds. Results: During the pandemic, 38 kidney transplants with an average length of hospital stay of 8.1 days were performed. Mean serum creatinine values of recipients were 0.91, 0.86, and 0.74 mg/dL on postoperative days 7, 30, and 90, respectively. During the pandemic, 9 living donor liver transplants (1 adult, 8 pediatric) were performed with an average length of hospital stay of 17.1 days. Mean serum total bilirubin levels were 0.9, 0.5, and 0.4 mg/dL on postoperative days 7, 30, and 90, respectively. Mean serum aspartate aminotransferase levels were 38.1, 28.3, and 22.3 U/L on postoperative days 7, 30, and 90, respectively. All recipients and donors were successfully discharged. Only 1 liver recipient died (on day 55 after discharge as a result of oxalosis-induced heart failure). Conclusions: According to our results, when precautions are taken, transplant does not pose a risk to patients during the pandemic period. We attribute the safety and success shown to our newly developed protocol in response to the COVID-19 pandemic.
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    Our Living Donor Protocol for Liver Transplant: A Single-Center Experience
    (2020) Karakaya, Emre; Akdur, Aydincan; Soy, Ebru H. Ayvazoglu; Harman, Ali; Coskun, Mehmet; Haberal, Mehmet; 0000-0002-0993-9917; 0000-0002-4879-7974; 0000-0002-3462-7632; 0000-0002-8726-3369; 0000-0001-5630-022X; 33187462; K-9824-2013; AAC-5566-2019; AAD-5466-2021; AAJ-8097-2021; AAA-3068-2021; AAM-4120-2021
    Objectives: The shortage of deceased donor organs is a limiting factor in transplant. The growing discrepancy between the wait list demand versus the supply of deceased donor organs has created an incentive for consideration of living donor liver transplant as an alternative. Here, we describe our evaluation process and donor complications. Materials and Methods: Since 1988, we have performed 659 (449 living donor and 210 deceased donor) liver transplants. The most important evaluation criteria is the relationship between donor and recipient, and we require that the donor must be related to the recipient. The evaluation protocol has 5 stages. Donor complications were defined as simple, moderate, and severe. Results: We retrospectively investigated data for 1387 candidates, and 938 (67.7%) were rejected; subsequently, 449 living donor liver transplants were performed. There were no complications in 398 of the donors (88.7%). Total complication rate was 11.3%. Simple complications were seen in 31 patients (6.9%). Moderate complications were seen in 19 patients (4.2%). We had only 1 severe complication, ie, organ failure from unspecified liver necrosis, which resulted in death. Conclusions: The relationship between donor and recipient and donor safety should be the primary focus for living donor liver transplant. Donor selection should be made carefully to minimize complications and provide adequately functional grafts.
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    LONG-TERM FOLLOW UP OF THE ORTHOPIC RENAL TRANSPLANT CASE WITH SPLENORENAL ANASTOMOSIS
    (2020) Soy, Ebru H. Ayvazoglu; Bovyat, Fatih; Coskun, Mehmet; Sezgin, Atilla; Haberal, Mehmet A.