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Publication Open Access A case of Burkitt’s lymphoma mimicking peritonitis carcinomatosa(Galenos Yayınevi, 2020) Örnek, Serdar; Tecimer Tülay; Ferhanoğlu, Ahmet Burhan; Büyüktaş, Deram; Faculty Member; Faculty Member; School of Medicine; 18320; N/APublication Open Access A clinical comparison of home-based and hospital-based exercise programs following arthroscopic capsulolabral repair for anterior shoulder instability(Human Kinetics, 2020) Atalar, Ata Can; Eren, Şule Meral; Uçak, Ayla; Çerezci, Önder; Eren, İlker; Canbulat, Nazan; Demirhan, Mehmet; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 168021; 58534; 9882Context: ideal rehabilitation method following arthroscopic capsulolabral repair surgery for anterior shoulder instability has not been proven yet. Although rapid or slow protocols were compared previously, home- or hospital-based protocols were not questioned before. Objective: the aim of this prospective unrandomized controlled clinical trial is to compare the clinical outcomes of home-based and hospital-based rehabilitation programs following arthroscopic Bankart repair. Design: non-randomized controlled trial. Setting: orthopedics and physical therapy units of a single institution. Patients: fifty-four patients (49 males and 5 females) with an average age of 30.5 (9.1) years, who underwent arthroscopic capsulolabral repair and met the inclusion criteria, with at least 1-year follow-up were allocated into 2 groups: home-based (n = 33) and hospital-based (n = 21) groups. Interventions: both groups received identical rehabilitation programs. Patients in the home-based group were called for follow-up every 3 weeks. Patients in the hospital-based group admitted for therapy every other day for a total of 6 to 8 weeks. Both groups were followed identically after the eighth week and the rehabilitation program continued for 6 months. Main Outcome Measures: Clinical outcomes were assessed using Disabilities of Arm Shoulder Hand, Constant, and Rowe scores. Mann-Whitney U test was used to compare the results in both groups. Wilcoxon test was used for determining the progress in each group. Results: groups were age and gender matched (P =.61, P =.69). Average number of treatment sessions was 13.8 (7.3) for patients in the hospital-based group. Preoperative Disabilities of Arm Shoulder Hand (27.46 [11.81] vs 32.53 [16.42], P =.22), Constant (58.23 [14.23] vs 54.17 [10.46], P =.13), and Rowe (51.72 [15.36] vs 43.81 [19.16], P =.12) scores were similar between groups. Postoperative scores at sixth month were significantly improved in each group (P =.001, P =.001, and P =.001). No significant difference was observed between 2 groups regarding clinical scores in any time point. Conclusions: we have, therefore, concluded that a controlled home-based exercise program is as effective as hospital-based rehabilitation following arthroscopic capsulolabral repair for anterior shoulder instability.Publication Open Access A clinical scoring system to predict the development of bronchopulmonary dysplasia(Thieme Medical Publishers, 2015) Hayran, Mutlu; Derin, Hatice; Ovalı, Fahri; N/A; Gürsoy, Tuğba; Faculty Member; School of Medicine; 214691Objective: This study aims to develop a scoring system for the prediction of bronchopulmonary dysplasia (BPD). Methods: Medical records of 652 infants whose gestational age and birth weight were below 32 weeks and 1,500g, respectively, and who survived beyond 28th postnatal day were reviewed retrospectively. Logistic regression methods were used to determine the clinical and demographic risk factors within the first 72 hours of life associated with BPD, as well as the weights of these factors on developing BPD. Predictive accuracy of the scoring system was tested prospectively at the same unit. ResultsBirth weight, gestational age, gender, presence of respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, hypotension were the most important risk factors for BPD. Therefore, a scoring system (BPD-TM score) ranging from 0 to 13 and grouped in four tiers (0-3: low, 4-6: low intermediate, 7-9: high intermediate, and 10-13: high risk) was developed based on these factors. Below the score of 4, 4.1% of infants (18/436), above the score of 9, 100% (29/29) of the infants developed BPD. The score was validated successfully in 172 infants. Conclusion: With this easy to use scoring system, one can predict the neonate at risk for BPD at 72 hours of life and direct preventive measures toward these infants.Publication Open Access A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology(Aves, 2017) Ulaşoğlu-Yıldız, Çiğdem; Aslan, Selçuk; Talı, Erhan Turgut; N/A; N/A; Onay, Aslıhan; Eser, Hale Yapıcı; Faculty Member; School of Medicine; N/A; 134359PURPOSE: Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables. METHODS: A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps ofVBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables. RESULTS: Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05). CONCLUSION: Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior thalamic radiation and superior longitudinal fasciculus that intersects with subinsular white matter. Studies with larger sample sizes and more detailed clinical assessments are required to understand the function of insula in the neurobiology of schizophrenia.Publication Open Access A multi-center study on the efficacy of eltrombopag in management of refractory chronic immune thrombocytopenia: a real-life experience(Galenos Yayınevi, 2019) Çekdemir, Demet; Güvenç, Serkan; Özdemirkıran, Füsun; Eser, Ali; Toptaş, Tayfur; Özkocaman, Vildan; Haydaroğlu Şahin, Handan; Ermiş Turak, Esra; Esen, Ramazan; Cömert, Melda; Sadri, Sevil; Aslaner, Müzeyyen; Uncu Ulu, Bahar; Karakuş, Abdullah; Selim Bapur, Derya; Alacacıoğlu, İnci; Aydın, Demet; Tekinalp, Atakan; Namdaroğlu, Sinem; Ceran, Funda; Tarkun, Pınar; Kiper, Demet; Çetiner, Mustafa; Yenerel, Mustafa; Demir, Ahmet Muzaffer; Yılmaz, Güven; Terzi, Hatice; Atilla, Erden; Malkan, Ümit Yavuz; Acar, Kadir; Öztürk, Erman; Tombak, Anıl; Sunu, Cenk; Salim, Ozan; Alayvaz, Nevin; Sayan, Özkan; Ozan, Ülkü; Ayer, Mesut; Gökgöz, Zafer; Andıç, Neslihan; Kızılkılıç, Ebru; Noyan, Figen; Özen, Mehmet; Pepedil Tanrıkulu, Funda; Alanoğlu, Güçhan; Özkan, Hasan Atilla; Aslan, Vahap; Çetin, Güven; Akyol Erikçi, Alev; Deveci, Burak; Ersoy Dursun, Fadime; Dermenci, Hasan; Aytan, Pelin; Gündüz, Mehmet; Karakuş, Volkan; Özlü, Can; Demircioğlu, Sinan; Akay Yanar, Olga Meltem; Özatlı, Düzgün; Ündar, Levent; Tiftik, Eyüp Naci; Türköz Sucak, Ayhan Gülsan; Haznedaroğlu, İbrahim; Özcan, Muhit; Şencan, Mehmet; Tombuloğlu, Murat; Özet, Gülsüm; Bilgir, Oktay; Turgut, Burhan; Özcan, Mehmet Ali; Bahriye Payzın, Kadriye; Sönmez, Mehmet; Ayyıldız, Orhan; Dal, Mehmet Sinan; Ertop, Şehmus; Turgut, Mehmet; Soysal, Teoman; Kaya, Emin; Ünal, Ali; Pehlivan, Mustafa; Atagündüz, Işık; Tuğlular Fıratlı, Tülin; Saydam, Güray; Diz Küçükkaya, Reyhan; N/A; Çetiner, Mustafa; Öztürk, Erman; Faculty Member; Doctor; School of MedicineObjective: the aim of the present study was to evaluate the efficacy and safety of eltrombopag, an oral thrombopoietin receptor agonist, in patients with chronic immune thrombocytopenia (ITP). Materials and Methods: A total of 285 chronic ITP patients (187 women, 65.6%; 98 men, 34.4%) followed in 55 centers were enrolled in this retrospective cohort. Response to treatment was assessed according to platelet count (/mm3) and defined as complete (platelet count of >100,000/mm3), partial (30,000-100,000/mm3 or doubling of platelet count after treatment), or unresponsive (<30,000/mm3). Clinical findings, descriptive features, response to treatment, and side effects were recorded. Correlations between descriptive, clinical, and hematological parameters were analyzed. Results: The median age at diagnosis was 43.9±20.6 (range: 3-95) years and the duration of follow-up was 18.0±6.4 (range: 6-28.2) months. Overall response rate was 86.7% (n=247). Complete and partial responses were observed in 182 (63.8%) and 65 (22.8%) patients, respectively. Thirty-eight patients (13.4%) did not respond to eltrombopag treatment. For patients above 60 years old (n=68), overall response rate was 89.7% (n=61), and for those above 80 years old (n=12), overall response rate was 83% (n=10). Considering thrombocyte count before treatment, eltrombopag significantly increased platelet count at the 1st, 2nd, 3rd, 4th, and 8th weeks of treatment. As the time required for partial or complete response increased, response to treatment was significantly reduced. The time to reach the maximum platelet levels after treatment was quite variable (1-202 weeks). Notably, the higher the maximum platelet count after eltrombopag treatment, the more likely that side effects would occur. The most common side effects were headache (21.6%), weakness (13.7%), hepatotoxicity (11.8%), and thrombosis (5.9%). Conclusion: results of the current study imply that eltrombopag is an effective therapeutic option even in elderly patients with chronic ITP. However, patients must be closely monitored for response and side effects during treatment. Since both response and side effects may be variable throughout the follow-up period, patients should be evaluated dynamically, especially in terms of thrombotic risk factors. / Amaç: bu çalışmanın amacı kronik immün trombositopeni (ITP) hastalarında bir oral trombopoietin reseptör agonisti olan eltrombopagın etkinlik ve güvenirliliğini değerlendirmektir. Gereç ve Yöntemler: elli beş merkezde izlem altındaki toplam 285 kronik ITP hastası (187 kadın, %65,6) bu geriye dönük küme çalışmasına alınmıştır. Tedaviye yanıt trombosit sayısına göre değerlendirilmiş ve tam yanıt (>100.000/mm3), kısmi yanıt (30.000-100.000/mm3 veya tedaviden sonra trombosit sayısının bir kat artmış olması) ve yanıtsızlık (<30.000/mm3) olarak tanımlanmıştır. Hastaların klinik bulguları, tanımlayıcı özellikleri, tedaviye yanıt ve yan etki bilgileri toplanmış ve aralarındaki ilişki incelenmiştir. Bulgular: tanı anında yaş ortalaması 43,9±20,6 (3-95) yıl olan hastalar ortalama 18,0±6,4 (6-28,2) ay izlenmiştir. Tam ve kısmi yanıtı içeren toplam yanıt %86,7 (n=247) bulundu. Sırasıyla 182 (%63,8) ve 65 (%22,8) hastada tam ve parsiyel tedavi yanıtları gözlenmiştir. Otuz sekiz hasta (%13,4) eltrombopag tedavisine yanıt vermemiştir. Altmış yaş üzerindeki hastalarda (n=68) toplam yanıt %89,7 (n=61) bulunurken, bu oran 80 yaş üzerindeki (n=12) hastalarda %83 (n=10) olmuştur. Tedavi öncesi trombosit sayısı göz önüne alındığında, eltrombopag, tedavinin 1., 2., 3., 4. ve 8. haftalarında trombosit sayısını anlamlı şekilde artırmıştır. Kısmi veya tam cevap için gereken süre arttıkça, tedaviye cevap önemli ölçüde azaldığı saptanmıştır. Eltrombopag tedavisinden sonra maksimum trombosit sayısı ne kadar yüksekse, yan etkilerin oluşabilme ihtimalinin o kadar yüksek olabildiği dikkati çekmiştir. En sık görülen yan etkiler baş ağrısı (%21,6), güçsüzlük (%13,7) ve hepatotoksisite (%11,8) ve trombozdur (%5,9). Sonuç: Mevcut çalışmanın sonuçları, eltrombopag tedavisinin kronik ITP’de, yaşlı hastalar dahil olmak üzere, etkili bir tedavi seçeneği olduğunu göstermektedir. Bununla birlikte, hastalar tedavi sırasında yanıt ve yan etkiler açısından yakından izlenmelidir. Hem cevap hem de yan etkiler, takip süresi boyunca değişken olabileceğinden, hastalar özellikle tromboz risk faktörleri açısından dinamik olarak değerlendirilmelidir.Publication Open Access A new method to determine reflex latency induced by high rate stimulation of the nervous system(Frontiers, 2014) Karacan, İlhan; Çakar, Halil İ.; Cidem, Muharrem; Kara, Sadık; N/A; Yılmaz, Gizem; Sebik, Oğuz; Türker, Kemal Sıtkı; PhD Student; Researcher; Faculty Member; School of Medicine; N/A; N/A; 6741High rate stimulations of the neuromuscular system, such as continuous whole body vibration, tonic vibration reflex and high frequency electrical stimulation, are used in the physiological research with an increasing interest. In these studies, the neuronal circuitries underlying the reflex responses remain unclear due to the problem of determining the exact reflex latencies. We present a novel 'cumulated average method" to determine the reflex latency during high rate stimulation of the nervous system which was proven to be significantly more accurate than the classical method. The classical method, cumulant density analysis, reveals the relationship between the two synchronously recorded signals as a function of the lag between the signals. The comparison of new method with the classical technique and their relative accuracy was tested using a computer simulation. In the simulated signals the EMG response latency was constructed to be exactly 40 ms. The new method accurately indicated the value of the simulated reflex latency (40 ms). However, the classical method showed that the lag time between the simulated triggers and the simulated signals was 49 ms. Simulation results illustrated that the cumulated average method is a reliable and more accurate method compared with the classical method. We therefore suggest that the new cumulated average method is able to determine the high rate stimulation induced reflex latencies more accurately than the classical method.Publication Open Access A possible role of prolonged whirling episodes on structural plasticity of the cortical networks and altered vertigo perception: the cortex of sufi whirling dervishes(Frontiers, 2017) Çakmak, Yusuf Ö.; Ekinci, Gazanfer; Heinecke, Armin; N/A; Çavdar, Safiye; Faculty Member; School of MedicineAlthough minutes of a spinning episode may induce vertigo in the healthy human, as a result of a possible perceptional plasticity, Sufi Whirling Dervishes (SWDs) can spin continuously for an hour without a vertigo perception.This unique long term vestibular system stimulation presents a potential human model to clarify the cortical networks underlying the resistance against vertigo. This study, therefore, aimed to investigate the potential structural cortical plasticity in SWDs. Magnetic resonance imaging (MRI) of 10 SWDs and 10 controls were obtained, using a 3T scanner. Cortical thickness in the whole cortex was calculated. Results demonstrated significantly thinner cortical areas for SWD subjects compared with the control group in the hubs of the default mode network (DMN), as well as in the motion perception and discrimination areas including the right dorsolateral prefrontal cortex (DLPFC), the right lingual gyrus and the left visual area 5 (V5)/middle temporal (MT) and the left fusiform gyrus. In conclusion, this is the first report that warrants the potential relationship of the motion/body perception related cortical networks and the prolonged term of whirling ability without vertigo or dizziness.Publication Open Access A retrospective study of 39 patients treated with anterior approach of thoracic and lumbar spondylodiscitis clinical manifestations, anterior surgical treatment, and outcome(Lippincott Williams and Wilkins (LWW), 2015) Yaldız, Can; Özdemir, Nail; Yaman, Onur; Feran, Hamit Güneş; Tansuğ, Tuğrul; Minoğlu, Mustafa; N/A; Yaman, Onur; Doctor; School of MedicineThe aim of this study is to report our 39 patients treated with anterior debridement and autologous iliac bone grafting with or without anterior instrumentation, which is the presumed treatment of choice for thoracic or lumbar spondylodiscitis.Our patients underwent surgical treatment of spondylodiscitis using anterior debridement and autologous iliac bone grafting with or without anterior instrumentation and were analyzed with a mean follow-up of 8 years (range, 2-11 years). Kaneda 2-rod system instrumentation was used in 12 patients, in total. Clinical outcomes were assessed by the Frankel grade. Radiographic fusion was characterized based on 3-dimensional computed tomography.Of the whole group, 20 patients suffered from tuberculous spondylodiscitis and 19 suffered from hematogenous spondylodiscitis. Pathogens responsible for pyogenic infection included Staphylococcus aureus (4 patients), Pseudomonas aeruginosa (3 patients), and Brucella melitensis (1 patient). Fifteen patients had thoracic involvement, 20 had lumbar involvement, and 4 had thoracolumbar junction involvement. Preoperative neurological deficits were noted in 13 of the 39 patients. In terms of Frankel grade, 8 patients have improved, 4 have remained the same, and 1 patient has worsened during the follow-up period. Imaging-documented fusion was achieved in 23 of 27 patients in the graft group (85% fusion rate) and 11 of 12 patients in the graft+Kaneda instrumentation group (91% fusion rate).There was no instrumentation failure, loosening, or graft-related complication such as slippage or fracture of the graft. This approach demonstrated a good recovery rate of neurological functions and a high fusion rate.
Publication Metadata only A risk grouping algorithm for predicting factors of persistently elevated prostate-specific antigen in patients following robot-assisted radical prostatectomy(Wiley, 2021) Micoogullari, Uygar; Cakici, Mehmet Caglar; Kisa, Erdem; Kilic, Furkan Umut; Ardicoglu, Arslan; Altinova, Serkan; Atmaca, Ali Fuat; Akbulut, Ziya; N/A; Balbay, Mevlana Derya; Canda, Abdullah Erdem; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 153320; 116202Objective: After radical prostatectomy, prostate-specific antigen(PSA) value measuring >= 0.1 ng/mL is defined as persistent PSA(pPSA) and in many studies, it was found to be associated with aggressive disease and poor prognosis. Our aim in this study is to point out the pathological and clinical factors affecting pPSA among the patients who underwent robot-assisted radical prostatectomy(RARP) in an experienced academic centre and to make a useful risk grouping algorithm that can predict pPSA value based on operative data. Methods: We examined records of 1273 patients who underwent RARP retrospectively. Preoperative, operative and postoperative data were collected. Based on the PSA values (ng/mL) measured after 4-to-8 weeks of RARP, patients were divided into two groups as pPSA group (Group1)(n = 97) with PSA values >= 0.1 ng/mL and undetectable PSA group (Group2)(n = 778) with PSA values <0.1 ng/mL. Later on, Group1 was further divided into Group1a (PSA:0.1-0.2 ng/mL) and Group 1b (PSA >= 0.2 ng/mL) to evaluate biochemical recurrence(BCR). Results: Multivariate logistic regression analyses of the collected data revealed that preoperative PSA >= 20 ng/mL, operation time, a postoperative international society of urological pathology (ISUP) grade of >= 4, pT 3-4 and pN were independently associated with pPSA. Based on these results, a risk grouping algorithm predicting pPSA was developed. By looking at the risk grouping algorithm pPSA was found in 98.9% of the cases with a preoperative PSA value of >= 20 ng/mL, an operation time of 150 min, a postoperative ISUP grade of 4-5, a positive lymphovascular invasion (LVI) status, pT3-T4, and pN+; while pPSA was found in 25.5% of the cases with a preoperative PSA value of <20 ng/mL, an operation time of 100 min, a postoperative ISUP grade of <4-5, a negative LVI status, pT<3-4 and pN-. The estimated BCR-free survival time was 16.3 months in Group 1a and 57.0 months in Group2 (P < .001). Adjuvant treatment ratio was 64.9% in Group1 and 7.1% in Group2 (P < .001). Conclusion: For the patients who underwent RARP, factors associated with aggressive disease can predict the PSA persistence. To plan our treatment modalities accurately, an applicable risk grouping algorithm in daily practice would be useful.Publication Open Access Anatomical variations of the hepatic artery: a closer view of rare unclassified variants(Via Medica Journals, 2021) Karataş, Cihan; Mecit, Nesimi; Karakaya, Afak Durur; Yıldırımoğlu, Turan; Kalayoğlu, Münci; Kanmaz, Turan; Faculty Member; Faculty Member; Koç University HospitalBackground: defining the hepatic artery anatomy is of great importance for both surgeons and radiologists. Michel classification was designed to classify hepatic artery variations. Nevertheless, there are variations that do not fit into this classification. In this study, we aim to define the incidence of all variations in a healthy liver donor by reviewing their CT scan with special emphasis on variations that do not fit in any of the Michel classes. Materials and methods: a retrospective analysis of CT scan of donors and potential liver donors who were evaluated by triphasic CT scan. The CT scans were reviewed independently by a radiologist and two transplant surgeons. Cases that did not fit in any of the Michel classes were classified as class 0. Results: out of 241 donors, 210 were classified within the Michel classification, of which 60.9 % were class I and 9.1% class II. Thirty-one donors (12.9%) classified as class 0. Of which, nine, three, two and three had replaced right hepatic artery from pancreaticoduodenal artery, gastroduodenal artery, aorta and celiac artery, respectively. Two and 6 donors had accessory right hepatic artery from pancreaticoduodenal artery and gastroduodenal artery respectively. Segment 4 artery originated from left and right hepatic artery in 56.8% and 31.9%, respectively. Conclusions: a great caution should be taken when evaluating the hepatic artery anatomy, clinicians should anticipate and be familiar with the rare unclassified variations of the hepatic artery.