Person: ÖNGEN, GÖKHAN
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ÖNGEN
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GÖKHAN
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Publication Non-contrast magnetic resonance venography with inhance 3D Velocity: Diagnostic performance for intracranial venous thrombosis(Springer, 2021-04-06) Özpar, Rifat; Tonkaz, Mehmet; Erkal, Duygu; Öngen, Gökhan; Hakyemez, Bahattin; ÖZPAR, RİFAT; TONKAZ, MEHMET; ERKAL TONKAZ, DUYGU; ÖNGEN, GÖKHAN; HAKYEMEZ, BAHATTİN; 0000-0001-6649-9287; 0000-0002-8201-1568; 0000-0002-3425-0740; AAH-5062-2021; DZJ-5260-2022; EUK-9600-2022; FQR-8472-2022; AAI-2318-2021Purpose The aim of this study was to evaluate the diagnostic performance of Inhance 3D Velocity (I3DV) in intracranial venous thrombosis and investigate the possible impact of venous sinus hypoplasia/aplasia on false thrombosis diagnosis made with I3DV. Methods This study included 540 patients. Contrast-enhanced magnetic resonance venography combined with conventional sequences was considered the gold standard test (GST), while I3DV was considered as diagnostic test. We accessed the diagnostic success of I3DV for intracranial venous thrombosis detection, thrombosed vessel identification, and total/partial thrombus distinction. The possible relationship between false-positive thrombus diagnosed by I3DV and venous sinus hypoplasia or aplasia diagnosed by GST was investigated. Results The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of I3DV in the detection of intracranial venous thrombosis were 95.7%, 92.1%, 64.1%, 99.3%, and 92.6%, respectively. A significant association was observed between I3DV and GST in terms of thrombosis detection and total/partial thrombus distinction (p < 0.001). A significant relationship was observed between false-positive thrombosis diagnosis in I3DV and hypoplasia in the left transverse sinus (p < 0.001). Conclusion Intracranial venous thrombosis may be diagnosed faster and more accurately than traditional phase contrast magnetic resonance angiography in I3DV. This technique can be used in situations where contrast medium application is contraindicated. As in other non-contrast magnetic resonance venography techniques, left transverse sinus hypoplasia can be diagnosed as a thrombosed vessel in I3DV.Publication An assessment of slap type 5 lesions using proton density oblique sagittal imaging in magnetic resonance arthrography(Sage Publications, 2021-12-10) Öngen, Gökhan; Gökalp, Gökhan; Nas, Ömer Fatih; ÖNGEN, GÖKHAN; GÖKALP, GÖKHAN; NAS, ÖMER FATİH; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Radyoloji Anabilim Dalı.; 0000-0002-3682-2474; FQR-8472-2022; GMO-0473-2022; AAG-8561-2021Background Bankart lesions accompany superior labrum anteroposterior (SLAP) lesions; these are called SLAP type 5. Purpose To compare SLAP type 5 lesions using routine magnetic resonance arthrography (MRA) and thin-slice oblique sagittal proton density (PDW) sequences and correlation operation results. Material and Methods In total, 181 patients were admitted with shoulder instability. The study was completed with 44 patients. The presence or absence of isolated Bankart and SLAP type 5 lesions in routine MRA and PDW oblique sagittal images were evaluated separately. Absence of rupture scored 0 points, suspected ruptures scored 1 point, and apparent ruptures scored 2 points. The two scores were compared with the shoulder arthroscopy findings. Results According to the findings in the shoulder arthroscopy, 40 patients had Bankart lesions and 17 patients had accompanying SLAP type 5 lesions. To detect a Bankart lesion, there was no significant difference between routine MRA sequences and PDW oblique sagittal images (P = 0.061). Routine MRA sensitivity was 95%, specificity 25%, positive predictive value (PPV) 92%, negative predictive value (NPV) 33%, while for PDW oblique sagittal images, sensitivity was 75%, specificity 100%, PPV 100%, and NPV 28.5%. In 8/17 type 5 SLAP lesions, routine MRA detected sensitivity 47%, specificity 92.6%, PPV 80%, and NPV 73.5%; in 14/17 SLAP type 5 lesions, PDW oblique sagittal images detected sensitivity 82%, specificity 100%, PPV 100%, and NPV 90% (P = 0.015). Conclusion The PDW oblique sagittal images may play a significant role in assessing the anterior and superior extent of the tears.Publication The association between the CT severity index and the pulmonary artery area in COVID-19 pneumonia(Sage Publications Ltd, 2022-01-24) Ongen, Gökhan; Gökalp, Gökhan; Nas, Ömer Fatih; Özpar, Rıfat; Candan, Selman; ÖNGEN, GÖKHAN; GÖKALP, GÖKHAN; NAS, ÖMER FATİH; ÖZPAR, RİFAT; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Radyoloji Anabilim Dalı.; 0000-0001-6649-9287; FQR-8472-2022; GMO-0473-2022; AAG-8561-2021; AAH-5062-2021Background The pulmonary artery area (PAA) is a valuable non-invasive method for the diagnosis of pulmonary hypertension. Purpose To compare the change in PAA in patients with COVID-19 with the computed tomography (CT) severity index using follow-up imaging. Material and Methods A total of 81 patients who were followed up and underwent CT assessment more than once at our hospital's pandemic department were evaluated retrospectively. Patients with progression were separated into three groups: progression ranging from mild-to-mild infiltration (Group A, CT severity index of 0-2); progression from mild to severe infiltration (Group B, CT severity index of 0-2 to 3-5); and progression from severe-to-severe infiltration (Group C, CT severity index of 3-5). The PAAs were calculated separately. Results The mean age was 56 +/- 12 years. In terms of those patients showing progression in the CT images, the number of patients in Groups A, B, and C was 29, 40, and 12 in the right lung; 32, 45, and 4 in the left lung; 23, 45, and 13 on both lungs, respectively. There was no significant difference between the main, right, and left PAAs in Group A (P > 0.05). In Group B, there were significant increases in the areas of the main, right, and left PAAs (P < 0.05). There were also significant increases in the areas of the right and main pulmonary arteries in Group C (P < 0.05). Conclusion PAAs increase as disease involvement advances in cases with COVID-19 pneumonia, which is thought to be correlated with progression.Publication Right- versus left-sided approach for transhepatic tunneled catheter placement: Is there a difference?(Springer, 2021-04-08) Nas, Ömer F.; Candan, Selman; Öztepe, Muhammed F.; Kandemirli, Sedat G.; Bilgin, Cem; İnecikli, Mehmet F.; Özkaya, Güven; Gökalp, Gökhan; Öngen, Gökhan; Erdoğan, Cüneyt; NAS, ÖMER FATİH; CANDAN, SELMAN; Öztepe, Muhammed F.; İNECİKLİ, MEHMET FATİH; ÖZKAYA, GÜVEN; GÖKALP, GÖKHAN; ÖNGEN, GÖKHAN; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Radyoloji Anabilim Dalı.; Bursa Uludağ Üniversitesi/Sağlık Bilimleri Enstitüsünde/Biyoistatistik Bilim Dalı.; 0000-0003-0297-846X; 0000-0002-3682-2474; AAK-5124-2020; HHS-7433-2022; GVS-7682-2022; AAG-8561-2021; DLB-1623-2022; IVU-2672-2023; GMO-0473-2022; FQR-8472-2022Objective We aimed to compare the technical difficulties, complications, long-term efficacy, and risks between right- and left-sided approach transhepatic tunneled catheterization. Methods We retrospectively evaluated transhepatic tunneled catheter placement cases in our institution between May 2012 and November 2019. Demographic and procedural parameters were recorded. Statistical tests were used to compare the complication rates of right- and left-sided approach. Furthermore, Cox regression analyses were used to investigate the relationship between functional catheter days and included parameters. Results A total of 83 procedures were performed in 46 patients, with a female to male ratio of 1.88 and a mean age of 55.5 +/- 18.2 years. Indication for catheter placement was chronic renal insufficiency and loss of central venous access through traditional routes in all cases. Median functional catheter durations were 28 days (1-382) and 55.5 days (1-780) for right-sided and left-sided access, respectively. Complication rates were similar for both sides. There was no difference between primary and revision procedures in terms of safety and efficacy outcomes. In univariate Cox regression analysis, gender was the only variable which was found to be statistically significant (HR = 2.014 (1.004-4.038)) for functional catheter days. In multivariate Cox regression model, gender and access side were included which failed to reach statistical significance. Conclusions In our study, both right- and left-sided approaches provided similar safety and efficacy outcomes, suggesting that both techniques can be employed based on physician's preference.Publication Effect of locoregional treatments in hepatocellular carcinoma: What are the pathologic/radiologic Milan Criteria?(Başkent Üniversitesi, 2023-10-01) Aksoy, Fuat; Dündar, Halit Ziya; Çelik, Fatih; Öngen, Gökhan; Nas, Ömer Fatih; Sağlam, Kutay; Gürlüler, Ercüment; Kıyıcı, Murat; Kaya, Ekrem; AKSOY, FUAT; DÜNDAR, HALİT ZİYA; ÇELİK, FATİH; ÖNGEN, GÖKHAN; NAS, ÖMER FATİH; SAĞLAM, KUTAY; GÜRLÜLER, ERCÜMENT; KIYICI, MURAT; KAYA, EKREM; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Organ Nakli Merkezi.; 0000-0001-5808-9384; 0000-0003-2728-9521; HII-8895-2022; X-7425-2018; EWI-3634-2022; JYY-5340-2024; FQR-8472-2022; JJS-3965-2023; JSD-3843-2023; FHW-0015-2022; JSF-3184-2023Objectives: Milan criteria is the most commonly used criteria for patients with hepatocellular carcinoma awaiting liver transplant. The effects of locoregional therapy on downstaging or bridging before liver transplant on survival remain controversial. Considering that the tumor size may change with locoregional therapy and formalin fixation after explantation, we aimed to evaluate the effects of locoregional therapy on radiological and pathological Milan criteria and survival.Materials and Methods: Demographic data, etiology, preoperative alpha-fetoprotein value, Child-Pugh and Model for End-Stage Liver Disease-Na scores, status of being inside or outside of radiological Milan criteria, status of being inside or outside of Milan criteria in explant (pathological Milan criteria), and the locoregional therapy types and combinations were evaluated for their effects on inclusion in Milan criteria and survival.Results: During the study period, 396 patients underwent liver transplant at our center, with 97 because of cirrhosis and hepatocellular carcinoma. When we viewed patients according to preoperative radiologic evaluations, 67.9% were within Milan criteria and 32.1% were outside. When we viewed according to explant (pathological) evaluations, 80.7% of patients were within Milan criteria. Among 97 patients, 71 (73.2%) had locoregional therapy (22 [30.9%] for downstaging, 49 [69.0%] for bridging to transplant), and 12 patients (12.3%) were within Milan criteria on explant examination while outside of Milan criteria before LT. One-year, 3-year, and 5-year survival rates were 80.7%, 76.1%, and 71.6%, respectively. Conclusions: As a result of radiological evaluations, in patients who were outside of Milan criteria and underwent locoregional therapy, explant pathology within Milan criteria had a positive effect on survival; however, after locoregional therapy, there was no significant effect on survival in patients who were still outside of Milan criteria.Publication Morphometric shape analysis of corpus callosum in children with down syndrome(Sage Publications Inc, 2023-08-31) Gürsel, Başak Erdemli; Ercan, İlker; Şahin, İbrahim; Öngen, Gökhan; ERDEMLİ GÜRSEL, BAŞAK; ERCAN, İLKER; Şahin, İbrahim; ÖNGEN, GÖKHAN; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Radyolog Anabilim Dalı.; Bursa Uludağ Üniversitesi/Sağlık Bilimleri Enstitüsü/Biyoistatistik Anabilim Dalı.; 0000-0002-2382-290X; 0000-0002-0047-1780; AAH-6568-2021; HII-7787-2022; ABF-2367-2020; JJO-9241-2023Down syndrome (DS) is characterized by varying degrees of mental retardation and delay in neurocognitive functions. Herein, we analyzed the morphometric shape of the corpus callosum (CC) in children with DS. Twenty-three DS cases underwent magnetic resonance imaging and have grossly normal CC, and 23 control group cases were included in this retrospective study (2012-2020). The CC was obtained from T2-weighted mid-sagittal images, and certain anatomical points were marked on the CC. Statistical geometric shapes and deformations of CC were evaluated for both groups. The age range of patients with DS and control group was 6 to 42 months. A statistically significant difference was found in the shape of CC between the groups (P < .001). Deformation was most evident in the splenium in the DS group.Publication Internal versus external biliary drainage in malignant biliary obstructions: Is there a difference in the rate of infection?(Sage Publications Ltd, 2023-08-23) Öngen, Gökhan; Nas, Ömer Fatih; Hacıkurt, Kadir; Dündar, Halit Ziya; Özkaya, Güven; Kaya, Ekrem; Hakyemez, Bahattin; ÖNGEN, GÖKHAN; NAS, ÖMER FATİH; ÖZKAYA, GÜVEN; KAYA, EKREM; HAKYEMEZ, BAHATTİN; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Radyoloji Anabilim Dalı.; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Genel Cerrahi Anabilim Dalı.; 0000-0002-3425-0740 ; 0000-0002-9562-4195; FQR-8472-2022; JJS-3965-2023; IVU-2672-2023; AAG-7319-2021; AAI-2318-2021Background: Percutaneous biliary drainage is a frequently used method to provide biliary decompression in patients with biliary obstruction.Purpose: To investigate the between drainage type and infection risk in patients treated with internal-external and external biliary drainage catheterization for malignant biliary obstruction.Material and Methods: A total of 410 patients with malignant biliary obstruction who underwent internal-external or external biliary drainage catheterization between January 2012 and October 2016 were retrospectively evaluated. We investigated the correlation between percutaneous biliary drainage technique and infection frequency by evaluating patients with clinical findings, bile and blood cultures, complete blood counts, and blood biochemistry.Results: There was no statistically significant difference between the selected patient groups (internal-external or external biliary drainage catheter placed) in terms of age, sex, primary diagnosis, receiving chemotherapy, catheter sizes, and outpatient-patient status. After catheterization, catheter-related infection was observed in 49 of 216 (22.7%) patients with internal-external and 18 of 127 (14.2%) patients with external biliary drainage catheters, according to the defined criteria. There was no difference in infection rate after the biliary drainage in the two groups (P > 0.05). There was also no difference concerning frequently proliferating microorganisms in bile cultures.Conclusion: Internal-external biliary drainage catheter placement does not bring an additional infection risk for uninfected cholestatic patients whose obstruction could be passed easily in the initial drainage.