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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
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Publication Metadata only Clinical results of anterior odontoid screw fixation for type II odontoid fractures(Turkish Neurosurgical Society, 2014) Keskin, Fatih; Gomleksiz, Cengiz; Sasani, Mehdi; Oktenoglu, Tunc; Suzer, Tuncer; Özer, Ali Fahir; Faculty Member; School of Medicine; 1022AIM: In this study, 31 patients with a diagnosis of Type II odontoid fractures were reported. All patients were treated with anterior transodontoid screw fixation and clinical outcomes were reported. MATERIAL and METHODS: In this study, the retrospective clinical analysis of 31 patients with traumatic type II odontoid fractures who were treated through anterior transodontoid fixation in Neurosurgery Department at VKV American Hospital between 1998 and 2012 was performed. The age, sex, cause of injury, diagnosis time, neurological examination before and after surgery, follow-up period were evaluated. The neurological status of patients was classified according to the Frankel scale. RESULTS: In 4 patients, 2 transodontoid screws were inserted. The mean hospital stay was 3.35 days. Posterior occipito-cervical fusion was done in 1 patient due to the lack of fusion in the first operation. No vascular injury, screw malposition, infection, neurologic deterioration, or complications were observed during the peroperative and postoperative stage. The mean postoperative follow-up period was 36 months after surgery. Radiological imaging of patients were performed at the early and late postoperative stage. CONCLUSION: We found satisfying fusion rates and better patient comfort during the postoperative period. We think that stabilization and fusion through a transodontoid screw is a minimal invasive method.AMAÇ: Çalışmada, Tip II odontoid fraktürü tanısı alan 31 olgu bildirilmiştir. Olguların hepsi anterior transodontoid vida fiksasyonu ile tedavi edilmiş ve klinik sonuçları bildirilmiştir. YÖNTEM ve GEREÇLER: Çalışma, VKV Amerikan Hastanesi Nöroşirürji Bölümü’nde 1998-2012 yılları arasında travmatik tip II odontoid kırığı nedeniyle anterior transodontoid fiksasyon ile cerrahi tedavi uygulanan 31 hastanın retrospektif klinik analizleri yapılmıştır. Tüm olguların yaş, cinsiyet, travma nedeni, teşhis zamanı, cerrahi girişim öncesi ve sonrasında nörolojik muayeneleri, takip süresi değerlendirilmiştir. Olguların nörolojik durumları Frankel skalasına göre sınıflandırılmıştır. BULGULAR: Dört hastaya 2 adet transodontoid vidası yerleştirildi. Hastanede kalış süresi ortalama 3,35 gün idi. 1 hastada postop takibinde füzyon oluşmaması nedeniyle ikinci bir operasyon ile posteriordan oksipitoservikal füzyon yapıldı. İşlem sırasında ve sonrasında damar yaralanması, vida malpozisyonu, enfeksiyon, nörolojik bozulma gibi komplikasyonlar izlenmedi. Hastalar ameliyat sonrasında ortalama 36 ay takip edildi. Hastaların erken ve geç dönemde radyolojik görüntülemeleri yapıldı. SONUÇ: Postoperatif dönemde hastaların takiplerinde tatmin edici füzyon oranı ve hasta konforunun daha iyi olduğunu saptadık. Tip II odontoid kırıklarının cerrahi tedavisinde minimal invaziv yöntem olan transodontoid vida ile fiksasyonun yüksek avantajlarından dolayı ilk seçenek olabileceğini düşünüyoruz.Publication Metadata only Peripapillary choroidal vasculature in pediatric eyes with type 1 diabetes mellitus(Kare Yayıncılık, 2022) N/A; N/A; Hasanreisoğlu, Murat; Kesim, Cem; Uzunay, Nur Sena; Taş, Ayşe Yıldız; Karslıoğlu, Melisa Zişan; Şahin, Afsun; Faculty Member; Teaching Faculty; Undergraduate Student; Faculty Member; Doctor; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; School of Medicine; School of Medicine; School of Medicine; N/A; School of Medicine; N/A; N/A; N/A; N/A; Koç University Hospital; N/A; 182001; 387367; N/A; 200905; N/A; 171267Objectives: choroidal vasculature change in children with diabetes mellitus is not investigated enough although it could reflect clinical outcome. Methods: pediatric Type 1 diabetes mellitus (T1DM) patients and healthy controls were retrospectively evaluated. Peripapillary retinal nerve fiber layer optical coherence tomography (OCT) images of the right eyes were analyzed. Choroidal parameters including total choroidal area, luminal area, stromal area, and choroidal vascularity index were measured through image binarization. Results: twenty eyes of 20 patients were compared with 46 eyes of 46 healthy controls. Mean total choroidal area, luminal area, and stromal area were 1.59±0.35, 1.10±0.24, and 0.50±0.13 mm2 in patients’ eyes and 1.52±0.49, 1.05±0.34, and 0.47±0.17 mm2 in healthy eyes. No difference was found in choroidal vascularity indices between patients and healthy eyes (68.8±3.9% vs. 69.4±4.4%, p=0.521). Temporal choroidal vascularity index was significantly higher than its nasal counterpart in healthy eyes (71.8±5.0% vs. 68.6±4.9%, p<0.001) which was not significant in patients’ eyes (70.7±4.0% vs. 68.9±5.1%, p=0.067). Temporal quadrant had the highest choroidal vascularity index score among all quadrants in healthy controls (all p<0.05), whereas no choroidal vascularity index difference between quadrants was detected in patients (p=0.75). Conclusion: peripapillary choroidal vasculature has shown subtle sectoral changes which did not reflect the overall peripapillary OCT section in pediatric T1DM patients when compared with healthy controls.Publication Metadata only Large-n analysis in the study of conflict(Center Foreign Policy & Peace Research, 2019) Department of International Relations; Akça, Belgin San; Faculty Member; Department of International Relations; College of Administrative Sciences and Economics; 107754In this paper; I examine the generation and use of large-N datasets and issues related to operationalization and measurement in the quantitative study of inter-state and infra-state conflict. Specifically, I critically evaluate the work on transnational dimensions of internal conflict and talk about my own journey related to my research on interactions between states and nonstate armed groups. I address the gaps in existing research, the use of proxy measures in large-N data analysis, and talk in detail about observational data collection and coding. I argue that future research should bridge the gap between studies of conflict across the fields of Comparative Politics and International relations. I make suggestions laying the standards of academic scholarship in collecting data and increasing transparency in research.Publication Metadata only Impact of COVID-19 pandemic on academic research and being demotivated(AVES, 2020) N/A; Aydemir, Duygu; Ulusu, Nuriye Nuray; PhD Student; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Graduate School of Health Sciences; School of Medicine; N/A; 6807N/APublication Metadata only The effect of thyroid eye disease on corneal biomechanical properties(Kare Yayıncılık, 2022) N/A; Cömert, Melis Cansu; Yılmaz, Sezen Güçlü; Taş, Ayşe Yıldız; Şahin, Afsun; Undergraduate Student; Undergraduate Student; Faculty Member; Faculty Member; School of Medicine; School of Medicine; School of Medicine; School of Medicine; N/A; N/A; 200905; 171267Objectives: the aim of this study was to identify corneal biomechanical parameters measured by ORA in patients with TED compared to the healthy group. The NOSPECS classification of patients is used to assess the relation between biomechanical changes and disease severity. Methods: we included 22 TED patients, diagnosed with TED for more than five years, and 43 healthy participants. The NOSPECS classification was assessed as mild (grade 1-3) and severe (grade 4-6) disease. For each group, corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), Goldmann-correlated intraocular pressure (IOPg) and corneal compensated intraocular pressure (IOPcc) parameters were measured by ORA. Results: the mean age was 38.8±11.6 years for the TED patients and 42.9±15.58 years for the control group. For TED patients and healthy volunteers, the mean levels of CRF, CH, and CCT were measured as follows: 10.43±2.04 vs 10.28±1.91mmHg, p=0.67; 10.18±1.81 vs 10.21±1.68 mmHg, p=0.90; 550.31±35.73 vs 545.23±37.91 µm, p=0.47, respectively. These values were not significant between groups, but they were significantly higher in females compared to males in TED patients [CRF;10.68 (IQR: 9.49-12.14) vs 8.96 (IQR: 8.04-9.92) mmHg, p=0.002, CH; 10.43 (IQR: 9.48-11.25) vs 8.58 (IQR: 7.90-9.95) mmHg, p=0.003 and CCT; 554.25 (IQR: 536.05-579.52) vs 527.40 (IQR: 492.25-545.90) μm, p=0.014]. CRF values were negatively correlated with NOSPECS score (r=-0.317, p=0.036) and significantly higher CRF was observed in mild patients compared to severe disease (11.43 (IQR: 10.14-12.87) vs 9.46 (IQR: 8.75-10.28) mmHg, p=0.008). Conclusion: we found a significant gender effect on corneal biomechanical parameters of TED patients. CRF, CH and CCT values were significantly higher in females compared to males with TED. The clinical severity score of TED showed negative correlation with CRF. CRF value might be a useful parameter in follow-up of TED patients in clinical practice.Publication Metadata only Gamma knife radiosurgery for hemorrhagic brainstem cavernomas(Turkish Neurosurgical Soc, 2019) Üçüncü Kefeli, Ayşegül; Şengöz, Meriç; N/A; Peker, Selçuk; Faculty Member; School of Medicine; Koc University Hospital; 11480AIM: To assess treatment results of gamma knife radiosurgery (GKRS) for hemorrhagic brainstem cavernous malformations (BSCMs). MATERIAL and METHODS: A retrospective review of patients with hemorrhagic BSCMs, who were treated at the Acibadem Kozyatagi Hospital GKRS unit from May 2007 to October 2015 was performed. RESULTS: In total, 82 patients were identified. All patients had experienced at least one hemorrhagic event (range 1-3), and all of them presented with radiological evidence of hemorrhage. The median target volume was 0.3 ml, and the median marginal radiation dose was 12 Gy. The mean durations before and after surgery were 25.5 (range 1-204) months, and 50.3 (range 13-113) months, respectively. Pre-treatment hemorrhage rates were calculated from the date of first hemorrhage to the date of radiosurgery. There were 97 bleeds over 174.4 patient-years during the observation period, with an annual hemorrhage rate of 55.7%. If the first bleed is excluded, the annual hemorrhage rate was 8.6%. Only three patients demonstrated re-bleeding, which occurred at 3, 12 and 79 months after radiosurgery. Over a total follow up time of 344 patient-years the annual re-bleeding rate was therefore 0.87%, indicating that the risk of BSCM hemorrhage was significantly decreased by radiosurgery. CONCLUSION: GKRS was a safe and effective treatment for symptomatic low volume BSCMs when a low marginal dose is used. A randomized controlled trial is needed that compares GKRS to observation if we want to establish the true efficacy of this treatment.Publication Metadata only Endoscopic papillectomy of benign ampullary lesions: outcomes from a multicenter study(Aves, 2018) Parlak, Erkan; Alper, Emrah; Disibeyaz, Selcuk; Cicek, Bahattin; Odemis, Bulent; N/A; Attila, Tan; Faculty Member; School of Medicine; 118342Background/Aims: Endoscopic papillectomy (EP) has emerged as an alternative to surgery in the management of ampullary lesions. The aim of this study is to evaluate feasibility, efficacy, safety, outcome, and impact of EP in the management of benign ampullary lesions. Materials and Methods: This is a multicenter, retrospective study of 44 patients who had EP of benign ampullary lesions. Results: Over the 11-year period, 44 (55.7%) of 79 patients underwent EP for benign ampullary lesions. Complete resection was achieved in 40 patients (91%). An underlying adenocarcinoma was the only risk factor for incomplete resection. Twenty-eight lesions (63.6%) were resected en-bloc and 16 lesions (36.4%) were resected in piecemeal fashion. Post-papillectomy histopathologic diagnoses were tubular adenoma in 14 patients (32%), invasive adenocarcinoma in 9 patients (20.5%), tubullovillous adenoma in 7 patients (16%), tubullovillous adenoma with carcinoma limited to the mucosal layer in 5 patients (11.3%), adenoma with high-grade dysplasia in 4 patients (9%), neuroendocrine tumor in 1 patient (2.3%), ganglioneuroma in 1 patient (2.3%), hamartomatous polyp in 1 patient (2.3%), adenofibroma in 1 patients (2.3%), and Brunner gland hyperplasia in 1 patient (2.3%). Seven (15.9%) procedure-related complications occurred: 3 (6.8%) bleeding, 2 (4.5%) pancreatitis, 1(2.3%) abdominal pain, and 1 (2.3%) stent migration to the pancreatic duct. Seven patients (17%) had recurrence. Conclusion: Endoscopic papillectomy is a safe and effective method and can be considered as a first-line approach in patients with benign ampullary lesions with intent for cure. It also allows for correct histological diagnosis and staging.Publication Metadata only Regulation and harmonisation of innovation policy in European Union Law(Hacettepe Üniversitesi Hukuk Fakültesi, 2019) N/A; Ayata, Zeynep; Faculty Member; Law School; 186694Innovation has been one of the most debated concepts of recent years and many see it as the most important motor for economic growth. As innovation affects many areas such as economic structure, consumer protection, environmental issues, labour markets, competition, global inequality, etc. public intervention and regulation is necessary. Furthermore because of its characteristics (diversity of relevant areas and stakeholders, rapid change, necessity of expertise, etc) innovation requires a different system of regulation. This system known as flexible regulation, recommended by the European Union, provides the advantages of being responsive to needs but does also have drawbacks. This article discusses the conceptual framework of flexible regulation and its criticism. The European Union while competing with both developed (United States of America) and developing (China) countries has been incentivising innovation through regulation and intervening in these processes to protect the public interest. This article also examines these interferences undertaken by different stakeholders and institutions. The discussion on how the European Union regulates, problems related to harmonisation and the success criteria is elaborated through examples in three different areas. The article concludes that the limits of the European Union’s harmonisation capacity and the complexity of decision making processes prevents the achievement of a uniform success throughout the member states. / Yenilik son dönemlerde çok tartışılan ve birçok kesim tarafından ekonomik büyümenin en önemli motoru olarak görülen bir kavram olmuştur. Yeniliğin ekonomik yapıdan tüketici haklarına, çevre sorunlarından iş gücü piyasalarına, uluslararası eşitsizlikten rekabetçi yapılara kadar varan çok taraflı etkilerinin olması bu alanda kamunun müdahalesini ve düzenlemesini de zorunlu kılmaktadır. Ayrıca yenilik, niteliği (çok çeşitli alanda ve çok paydaşlı olması, hızla değişmesi ve uzmanlık bilgisi gerektirmesi gibi) gereği farklı bir düzenleme sistemi ihtiyacı doğurmaktadır. Avrupa Birliği tarafından da önerilen, esnek hukuki yapı olarak tarif edilen bu sistem, ihtiyaca çabuk cevap vermeyi kolaylaştırmakta ama bazı sakıncaları da beraberinde getirmektedir. Makalede esnek hukukun kuramları ve onlara getirilen eleştiriler tartışılmaktadır. Gelişmiş ülkelerle (Amerika Birleşik Devletleri) ve hatta gelişmekte olan ülkelerle (Çin) rekabet halinde olan Avrupa Birliği son yıllarda düzenleme yoluyla yenilikçiliğe destek vermekte ve bu süreçlere kamu yararına müdahale etmektedir. Farklı paydaşlar ve kurumlar aracılığı ile yapılan bu düzenlemeler makalenin bir diğer odak noktasını oluşturmaktadır. Üç ayrı alan temelinde örneklenerek yapılan bu tartışmada Avrupa Birliği’nin ne şekilde düzenleme oluşturduğu, uyumlaştırma sorunları ve başarı ölçütleri tartışılmaktadır. Sonuç olarak Avrupa Birliği’nin içinde yaşanılan uyumlaştırma sorunları ve karar alma süreçlerinin karmaşıklığının üye ülkeler arasında yeknesak bir başarı olmamasına yol açtığına işaret edilmektedir.Publication Metadata only Graft versus host disease after liver transplantation: a case report(Kare Yayıncılık, 2022) Acar, Sencan; Arat, Mutlu; Tecimer, Tulay; Polat, Kamil Yalcin; Akyıldız, Murat; Faculty Member; School of Medicine; 123080Graft Versus Host Disease (GVHD) is a severe immunological-clincopathological condition mediated by healthy T-lymphocytes in donor tissue against the immunosuppressed host tissue and rarely seen after solid organ transplantation (SOT). A 72-year old male patient underwent cadaveric liver transplantation. On day 34 of the postoperative follow-up, the patient developed fever, generalized skin rash and hemorrhagic lesions in the oropharynx. Skin biopsy was consistent with GVHD. Despite high-dose corticosteroid treatment, he died on postoperative day 51. Although it is seen rarely after liver transplantation, GVHD is an important clinical entity for which early diagnosis is critical due to its high rates of mortality.Publication Metadata only Cornerstones of biochemistry in stamps(Walter De Gruyter Gmbh, 2016) N/A; Ulusu, Nuriye Nuray; Faculty Member; School of Medicine; 6807N/A