Publications without Fulltext
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
Browse
254 results
Filters
Advanced Search
Filter by
Settings
Search Results
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 Determination of thyroglobulin levels by radioimmunoassay method in anti thyroglobulin positive differentiated thyroid patients: one center clinical experience(Pergamon-Elsevier Science Ltd, 2020) Uçar, Burcu; Şen, Melis; Acar, Tayfun; N/A; Demirkol, Mehmet Onur; Faculty Member; School of Medicine; 196946It is very crucial to determine Tg accurately and precisely in thyroid cancer cases. Although there are many studies on the detection of Tg in thyroid cases in the literature, there are no sufficient clinical studies examining many cases with different features by using RIA methodology. Here, a radiometric and chromatographic method has been studied for the first time to eliminate the interference from anti-Tg positive patients. In this paper, radioimmunoassay (RIA) and immunoradiometric (IRMA) techniques were used for the analysis of 302 sera collected from patients for Tg and TgAb quantification. By the RIA technique, a reliable result was obtained by calculating the real Tg value quantitatively in 41 patients showing TgAb positivity out of 208 patients. Our findings show that the RIA assay is the most suitable approach for detection of changeable (low or undetectable) Tg value and metastases detected by post-therapeutic imaging in early-stage DTC cases showing preoperative and postoperative TgAb positivity. The new immunoradiometric method allows the real (%) Tg value to be reached in a part of TgAb-positive DTC. Even if TgAb positive in the metastatic and nonmetastatic DTC patient group. This allows the accurate clinical follow-up of patients.Publication Metadata only Resonant channel-dropping filter with integrated detector system based on optical fiber coupler and microsphere(IOP Publications, 2004) İşci, Şenol; Yılmaz, Yiğit; Department of Physics; Serpengüzel, Ali; Kurt, Adnan; Bilici, Temel; Faculty Member; Teaching Faculty; N/A; Department of Physics; College of Sciences; N/A; 27855; 194455; N/APublication Metadata only Basilar artery occlusion management: an international survey of middle versus high-income countries(Sage, 2022) Drumm, Brian; Herning, Ana; Klein, Piers; Raymond, Jean; Abdalkader, Mohamad; Huo, Xiaochuan; Chen, Yimin; Siegler, James E.; Peacock, Meabh; Schonewille, Wouter J.; Liu, Xinfeng; Hu, Wei; Ji, Xunming; Li, Chuanhui; Alemseged, Fana; Liu, Liping; Nagel, Simon; Strbian, Daniel; Rebello, Leticia C.; Yaghi, Shadi; Qureshi, Muhammad M.; Fischer, Urs; Tsivgoulis, Georgios; Kaesmacher, Johannes; Yamagami, Hiroshi; Puetz, Volker; Sylaja, Pn; Marto, Joao Pedro; Sacco, Simona; Kristoffersen, Espen Saxhaug; Demeestere, Jelle; Conforto, Adriana B.; Meyer, Lukas; Kaiser, Daniel P. O.; Reiff, Tilman; Romoli, Michele; Diana, Francesco; Lobotesis, Kyriakos; Roi, Dylan; Masoud, Hesham E.; Ma, Alice; Mohammaden, Mahmoud H.; Doheim, Mohamed F.; Zhu, Yuyou; Sang, Hongfei; Sun, Dapeng; Ton, Mai Duy; Raynald; Li, Fengli; Lapergue, Bertrand; Hanning, Uta; Yang, Qingwu; Lee, Jin Soo; Thomalla, Gotz; Yang, Pengfei; Liu, Jianmin; Campbell, Bruce C., V; Chen, Hui-Sheng; Zaidat, Osama O.; Qiu, Zhongming; Nogueira, Raul G.; Miao, Zhongrong; Nguyen, Thanh N.; Banerjee, Soma; N/A; Aydın, Kubilay; Doctor; N/A; Koç University Hospital; N/ABackground and Purpose: Two early basilar artery occlusion (BAO) randomized controlled trials (RCTs) did not establish the superiority of endovascular thrombectomy (EVT) over medical management. Yet many providers continued to recommend EVT. The goal of the present article is to compare physicians' diagnostic and management strategies of BAO among middle-income and high-income countries (MICs and HICs, respectively). Methods: We conducted an international survey from January to March 2022 regarding management strategies in acute BAO, to examine clinical and imaging parameters influencing clinician management of patients with BAO. We compared responses between physicians from HIC and MIC. Results: Among the 1245 respondents from 73 countries, 799 (64.2%) were from HIC, with the remaining 393 (31.6%) from MIC. Most respondents perceived that EVT was superior to medical management for acute BAO, but more so in respondents from HIC (98.0% vs. 94.2%, p < 0.01). MIC respondents were more likely to believe further RCTs were warranted (91.6% vs. 74.0%, p < 0.01) and were more likely to find it acceptable to enroll any patient who met a trial's criteria in the standard medical treatment arm (58.8% vs. 38.5%, p < 0.01). Conclusions: In an area where clinical equipoise was called into question despite the lack of RCT evidence, we found that respondents from MIC were more likely to express willingness to enroll patients with BAO in an RCT than their HIC counterparts.Publication Metadata only Indications, effectiveness and safety of percutaneous endoscopic gastrostomy: a single center experience and literature review(H E C Press, Healthy Eating Club Pty Ltd, 2021) Saka, Bulent; Zirtil, Cansu; Erten, Sebile Nilgün; Altınkaynak, Mustafa; Akyüz, Filiz; Çavuş, Bilger; Özmen, Bahar; Büyükdemir, Serpil; Taşçıoğlu, Cemil; N/A; Akpınar, Timur Selçuk; Faculty Member; School of Medicine; 216646Background and Objectives: Percutaneous endoscopic gastrostomy (PEG) has been widely used since 1980 in enteral feeding of patients that are not able to be fed orally for a long time. The aim of this study is to evaluate the PEG indications, effectiveness and PEG related complications from a single center in Istanbul, Turkey. Methods and Study Design: 265 patients with PEG who were followed up by the clinical nutrition team of a university hospital between 2010-2018 were evaluated retrospectively. Nutritional Risk Screening-2002 (NRS-2002) test, anthropometric measurements, bioelectrical impedance analysis and laboratory data were used to evaluate the patients' nutritional status. Results: The most common indications for PEG were dementia (35.1%), amyotrophic lateral sclerosis (22.6%), stroke (15.8%), and cancer (14%). The mean body weight of the patients was increased after PEG (63.5 +/- 12.2 vs 62.0 +/- 12.7 kg). Mid upper arm circumference and calf circumference of the patients increased after PEG (27.5 +/- 2.5 vs 25.4 +/- 3.1 cm and 32.2 +/- 7.9 vs 29.6 +/- 5.9 cm, respectively). Serum albumin of the patients was increased significantly after PEG (3.34 +/- 0.69 g/dL to 3.64 +/- 0.65 g/dL) without any significant change in serum CRP. Subgroup analyses showed a significant increase in the mean serum albumin of patients with dementia after PEG (3.23 +/- 0.67 g/dL to 3.54 +/- 0.58 g/dL). Local insertion site infection occurred in 15 patients (5.6%) and only 3 patients had systemic inflammatory symptoms after local infection (1.1%). Conclusions: The results of our study showed that long-term enteral feeding with PEG is an effective and safe method that provides improvement in nutritional status.Publication Metadata only Understanding follicle growth in vitro: are we getting closer to obtaining mature oocytes from in vitro-grown follicles in human?(Wiley, 2017) Güzel, Yılmaz; N/A; Öktem, Özgür; Faculty Member; School of Medicine; 102627Obtaining and fertilizing mature oocytes from immature follicles that were grown outside the body has conceptually attracted scientists for centuries, with initial attempts first documented in the 19th century. Significant progress has been made since then, due in part to a better understanding of folliculogenesis and improved techniques of in vitro follicle growth. Indeed, in vitro growth is now considered a reasonable approach to preserve or restore fertility when immature follicles and their oocytes need to be grown and matured outside the body. Certain patients would benefit from in vitro follicle growth, particularly those who carry a risk of cancer re-seeding after grafting of frozen-thawed ovarian tissue or who are at the risk of premature ovarian failure due to several intrinsic ovarian defects and genetic mutations that lead to accelerated follicle atresia and early exhaustion of the ovarian reserve. This review provides an update on the current status of in vitro growth of preantral human follicles, from initial efforts to the most recent achievements.Publication Metadata only Jendrassik maneuver effect on spinal and brainstem reflexes(Springer, 2019) Kumru, Hatice; Opisso, Eloy; Valls-Sole, Josep; Cecen, Serpil; N/A; Ertuğlu, Lale Aslıhan; Aydın, Aslı; Türker, Kemal Sıtkı; Undergraduate Student; Undergraduate Student; Faculty Member; School of Medicine; School of Medicine; School of Medicine; Koç University Hospital; N/A; N/A; 6741The effect of Jendrassik Maneuver (JM) has been extensively studied on monosynaptic reflexes in numerous muscles below the level at which the maneuver was performed. Here we hypothesize that the effect of JM could be observed also on other reflexes, indicating a widespread influence of performing a motor act such as the JM. We examined polysynaptic reflexes caudal (i.e., the withdrawal reflex of the lower extremities) and rostral (i.e., the blink reflex to supraorbital nerve stimulation) to the level of JM contraction. We have assessed soleus tendon (T) reflex; withdrawal reflex in tibialis anterior and soleus muscle; blink reflex (BR), blink reflex excitability recovery curve (BR-ER) and prepulse inhibition of the blink reflex. Our results showed that (1) T-reflex amplitude increased during JM and decreased just after and 15 min after JM; (2) no change in the withdrawal reflex; (3) R2 area of BR reduced significantly just after or 15 min after JM; (4) Prepulse inhibition in BR reduced significantly during JM; (5) no change in BR-ER. Our results indicate that JM leads to generalized effects on neural excitability at both caudal and rostral levels. Furthermore, JM has a selective effect on excitability of reflex circuitries.Publication Metadata only Structures and properties of NbOF3 and TaOF3 - with a remark to the O/F ordering in the SnF4 type structure(Wiley-V C H Verlag Gmbh, 2002) Köhler, J; Simon, A; van Wullen, L; Cordier, S; Roisnel, T; Poulain, M; Department of Chemistry; Somer, Mehmet Suat; Faculty Member; Department of Chemistry; College of Sciences; 178882Powder samples of NbOF3 und TaOF3 were prepared by heating mixtures of NbO2F and NbF5 or TaO2F and TaF5, respectively, in the corresponding stoichiometric ratio in platinum crucibles under argon atmosphere (180-220degreesC). Both oxide fluorides are coulourless with a slight greyish tinge. They are sensitive to moisture and decompose in air at room temperature within hours. Both, NbOF3 and TaOF3 crystallize as a variant of the SnF4 type structure, space group 14/mmm. The structures have been refined from X-ray powder diffraction data using the Rietveld method (a = 3.9675(1) Angstrom, c = 8.4033(1) Angstrom, R-B = 3.60%, R-p = 4.58% for NbOF3 and a = 3.9448(1) Angstrom, c = 8.4860(1) Angstrom, R-a = 2.07%, R-p = 2.44% for TaOF3). Characteristic building units are sheets of corner sharing MX6 octahedra which are stacked via van der Waals interactions to a three dimensional framework. The occupancy of the two crystallographic sites for the anions by O and F is discussed on the basis of structure refinements, bond order summations, IR and NMR data and calculations of the Madelung parts of the lattice energy.Publication Metadata only Late tricuspid regurgitation after percutaneous transcatheter closure of ventricular septal defect: an educational presentation(Sociedade Brasileira de Cirurgia Cardiovascular, 2021) Sarkışlalı, Kamil; N/A; Kalangos, Afksendiyos; Faculty Member; School of Medicine; 286247Transcatheter closure of ventricular septal defects (VSD) is not out of complications. Late complications are rare, but important, and sometimes require surgical correction. Herein, we report a case of tricuspid regurgitation as a complication of transcatheter VSD closure. The patient underwent successful surgery. Postoperative course was satisfactory. Echocardiographic examination revealed well-functioning tricuspid valve. We present this case since valve regurgitation after transcatheter procedure requiring surgery is an uncommon but significant complication due to heart failure risk. Even in the absence of any clinical finding, post-procedural close follow-up is important for early diagnosis of the problem to prevent the aforementioned risk.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.