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Publication Metadata only Abo and rh blood groups and risk of myelomeningocele(Turkish Neurosurgical Soc, 2020) Isik, Semra; Cevik, Serdar; Turhan, Ali Haydar; Hanimoglu, Hakan; N/A; Baygül, Arzu Eden; Faculty Member; School of Medicine; 272290AIM: To investigate the relationship between the distribution of ABO or Rhesus (Rh) blood group antigens and the incidence of myelomeningocele. MATERIAL and METHODS: A retrospective data was reviewed for all myelomeningocele patients operated at a tertiary academic hospital between years 2014 and 2019. Age, sex, delivery method, physical and neurological examination findings, and radiological findings alongside with blood type of each patient were recorded. The data of blood group distribution among the study patients was compared to the data of healthy individuals in the same region. RESULTS: Patients with group B and AB showed a higher chance of developing myelomeningocele. Rh-positive blood group was associated with high incidence of myelomeningocele (93.5%), whereas Rh-negative blood group showed least association (6.5%). Rh-positive blood group was also found to be more frequent in patients with myelomeningocele with hydrocephalus and Chiari malformation. CONCLUSION: The findings of this study show that ABO and Rh blood groups have an effect on the development of myelomeningocele under the influence of environmental or genetic factors.Publication Open Access Antimuscarinic-induced convulsions in fasted rats after food intake: EEG patterns of fasting, scopolamine treatment, and convulsions(Galenos Yayınevi, 2022) Türkmen, Aslı Zengin; Nurten, Asiye; Edis, Bilge Özerman; Özen, İlknur; Kara, İhsan; Karamürsel, Sacit; Faculty Member; School of Medicine; 19597Objective: antimuscarinic treatment in fasted mice and rats causes clonic convulsion soon after food intake. This study was designed to evaluate the electrophysiological markers of these convulsions and fasting in electrocorticograms in rats. Methods: Male Wistar albino rats were stereotaxically implanted with 10 cortical electrodes, and baseline electroencephalogram recordings were taken for 10 minutes. After weighing, rats were deprived of food for 52 hours. At the 24th and 52nd hours of deprivation, continuous electroencephalogram recordings were repeated. After the deprivation period, animals were treated with saline or scopolamine (3 mg/kg). Twenty minutes after injections, animals were given food pellets. After eating food, electroencephalogram recordings were taken for 60 minutes and all animals were observed simultaneously to determine the incidence and onset of convulsions. Results: these results show that food deprivation for 52 hours decreased the amplitude of the gamma band when compared to basal (P <.05) and 24 hours (P <.008) food deprivation. And the amplitude of the beta band in the 52nd hour decreased when compared to the 24th hour of food deprivation (P <.05). The treatment with scopolamine changes the effects of food deprivation on the electroencephalogram. As a typical epileptiform manifestation, refeeding after scopolamine treatment caused a series of high-voltage polyspikes and synchronized spikes with a predominant frequency in the 1-3 Hz range. Conclusions: it was revealed that the behavioral patterns of rats and the electroencephalogram properties in these convulsions are in accordance with each other.Publication Metadata only Assessment of the MRI and behavioral test results in a focal cerebral ischemia-reperfusion model in the rat after separate and combined use of mouse-derived neural progenitor cells, human-derived neural progenitor cells and atorvastatin(Turkish Neurosurgical Soc, 2018) Tanta, Alican; Izgi, Nail; Erdag, Ece; Aras, Yavuz; Genc, Cetin; N/A; Önder, Tuğba Bağcı; Faculty Member; School of Medicine; 184359AIM: To assess the efficacy of Neural progenitor cell (NPC) transplantation in ischemic stroke, and to investigate whether atorvastatin enhances therapeutic potency of NPC after stroke. MATERIAL and METHODS: The focal cerebral ischemia-reperfusion model was performed by transient occlusion of middle cerebral artery. Rats were assigned randomly to receive intracerebral transplantation of mouse NPC alone (mNPC), human NPC alone (hNPC), mouse NPC plus oral atorvastatin (mNPC+A), human NPC plus oral atorvastatin (hNPC+A), oral atorvastatin alone, or intracerebral Dulbecco's Modified Eagle's medium injection (control group). Adhesive removal, rotarod, cylinder tests, and magnetic resonance imaging (MRI) were used for assessment of rats during 4 weeks. After sacrification on 28th day, rats were investigated by immunofluorescent staining. RESULTS: The hNPC and mNPC groups showed significantly improved functional outcome and reduced infarct area ratio compared with the control group. The hNPC group had significantly better performance and lower infarct area ratio than the mNPC group. Addition of atorvastatin to stem cell therapy significantly improved functional outcome, although it did not affect the infarct area ratio on MRI. Anti-inflammatory response in the infarct area was higher in the mNPC group. NPC transplantation significantly reduced the amount of microglia and a significant increase in the amount of astrocytes. CD8a+ T lymphocyte and granzyme B activities were not detected in any of the subjects. CONCLUSION: Both hNPC and mNPC treatments significantly improved functional outcome, and reduced infarct area ratio after stroke. Atorvastatin enhanced the therapeutic potency of NPCs, including neurological improvement.Publication Metadata only Biomechanical effect of graded facetectomy on asymmetrical finite element model of the lumbar spine(Turkish Neurosurgical Soc, 2014) N/A; Erbulut, Deniz Ufuk; Researcher; School of Medicine; 37661AIM: Facetectomy is a leading surgical method for stenosis treatment. The objective of this study was to investigate biomechanical effect of graded facetectomy on the lumbar spine using an asymmetrical finite element model. MATERIAL and METHODS: A validated 3-dimensional asymmetrical finite element model of lumbar L1-L5 was developed based on computerized tomography (CT) scans. All components were assigned material properties mimicking original spinal components. Graded facetectomy was performed by removing facet elements along with surrounding capsular ligaments. RESULTS: All three planes of motion were simulated and resulting range of motion at the index level, L4-L5, was compared with the intact model. Left unilateral facetectomy caused increase in range of motion by 14.6%, 87.4%, 94.5%, 10.5%, 6.3% and 8.8% for flexion, extension, left and right axial rotation, and left and right lateral bending, respectively. Total bilateral facetectomy resulted in an increase in motion by 33.6%, 238.7%, 120.4, 151.3%, 15.6% and 12.4% for flexion, extension, left and right axial rotation, and left and right lateral bending, respectively. CONCLUSION: Extension and axial rotation were found to be affected by the facet removal whereas flexion and lateral bending were mildly affected.Publication Open Access Changes in the expression of c-fos and AQP4 in the hippocampus and amygdala regions of rats with kainic acid-induced temporal lobe epilepsy and their role in the pathogenesis of disease(Galenos Yayınevi, 2022) Taşkıran, Emine; Yılmaz, Canan Uğur; Orhan, Nurcan; Kaya, Mehmet; Arıcan, Nadir; Bahçeci, Metin Berkant; Kaya, Mehmet; Gürses, Rabia Candan; Ahıshalı, Bülent; Faculty Member; Faculty Member; Faculty Member; School of Medicine; 10486; 110149; N/AObjective: aquaporin4 is the main water channel in the brain that is associated with neurological disorders. The role and the expressive changes of aquaporin4 in epilepsy are still limited and controversial. The study aims to evaluate the expression of c-fos and aquaporin4 during epileptogenesis after systemic kainic acid-induced status epilepticus in the temporal lobe epilepsy animal model and to investigate their alterations in both hippocampus and amygdala. Methods: intraperitoneal injections of kainic acid (5-15 mg/kg) by repeated low kainic acid protocol were given to young adult 32 Wistar albino rats for status epilepticus. Aquaporin4 and c-fos were investigated in the hippocampus and amygdala on days 1 and 60 after status epilepticus by immunostaining methods in brain slices. Results: the intensity of c-fos immunostaining rose considerably in the hippocampus CA1 area of rats during the acute period (P < 0.05) and in the amygdala during the chronic period. The immunostaining intensity of aquaporin4in the hippocampus of rats with acute kainic acid increased significantly (P <.05). It was also raised in the hippocampal region of the rats in the acute sham and chronic kainic acid groups. Discussion: the results of this study support a link between aquaporin4 and epilepsy. It can be speculated that aquaporin4 change is primarily a defense mechanism immediately after status epilepticus, and then, it can evolve into a causal factor with exhaustion as a result of overuse.Publication Open Access Clinical and molecular genetic findings of cerebral arteriopathy with subcortical infarcts and leukoencephalopathy(Galenos Yayınevi, 2021) Rüstemoğlu, Burcu Sevinç; Samancı, Bedia; Tepgeç, Fatih; Kürtüncü, Murat; Gündüz, Tuncay; Sayın, Gözde Yeşil; Gürvit, Hakan; Bilgiç, Başar; Toksoy, Güven; Eraksoy, Mefkure; Hanagasi, Hasmet; Uyguner, Zehra Oya; Altunoğlu, Umut; Avcı, Şahin; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 126174; N/AObjective: most lacunar strokes are sporadic, and hypertension, diabetes, smoking, and cardiovascular diseases are among its main risk factors. Strokes caused by small vessel diseases are generally associated with single-gene disorders with familial dominant and recessive inheritance. The most common condition is cerebral autosomal dominant arteriopathy, with subcortical infarcts and leukoencephalopathy (CADASIL), associated with the NOTCH3 gene. An infrequent form of this disease is the cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), revealed with pathogenic HTRA1 gene variants related to distinct molecular pathways. The neurological and cranial magnetic resonance imaging (MRI) findings are very similar to CADASIL; however, earlier than expected onset of common alopecia in man, low back pain, and more severe memory impairment are the differences in terms of clinical presentations. Clinical findings of 22 patients from 16 families with widespread white matter lesions in the periventricular field in the brain were investigated with molecular genetic findings. Materials and Methods: clinical examination results and cranial MRI findings are reported, and NOTCH3 and HTRA1 genes are sequenced stepwise by Sanger and next-generation sequencing techniques. Results: missense changes in epidermal growth factor (EGF)-like domain in the NOTCH3 are found in 18 cases from 14 families. Two different homozygous pathogenic missense and non-sense variants, in the HTRA1 gene, were detected in four patients from two families. The disease onset age was approximately 16 years earlier in cases carrying pathogenic variants located in the encoding region of EGF-like domains 1-6 of NOTCH3. Conclusion: In the NOTCH3 gene with c.382T>C (p.C128R), c.555T>G (p.C185W), and c.1903C>T (p.R635C) and in the HTRA1 gene c.235C>T (p.Q79*) are presented for the first time in this study. Molecular genetic investigation of CADASIL and CARASIL is important to support the clinical diagnosis, determine the inheritance model, provide patient and family counseling, manage disease process, and evaluate possible treatment strategies.Publication Metadata only Clinical and molecular genetic findings of cerebral arteriopathy with subcortical infarcts and leukoencephalopathy(Turkish Neurosurgical Society, 2021) Rüstemoğlu, Burcu Sevinç; Samancı, Bedia; Tepgeç, Fatih; Kürtüncü, Murat; Gündüz, Tuncay; Sayın, Gözde Yeşil; Gürvit, Hakan; Bilgi, Başar; Eraksoy, Mefkure; Hanağası, Haşmet; Uyguner, Zehra Oya; N/A; Altunoğlu, Umut; Avcı, Şahin; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 126174; N/AObjective: Most lacunar strokes are sporadic, and hypertension, diabetes, smoking, and cardiovascular diseases are among its main risk factors. Strokes caused by small vessel diseases are generally associated with single-gene disorders with familial dominant and recessive inheritance. The most common condition is cerebral autosomal dominant arteriopathy, with subcortical infarcts and leukoencephalopathy (CADASIL), associated with the NOTCH3 gene. An infrequent form of this disease is the cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), revealed with pathogenic HTRA1 gene variants related to distinct molecular pathways. The neurological and cranial magnetic resonance imaging (MRI) findings are very similar to CADASIL; however, earlier than expected onset of common alopecia in man, low back pain, and more severe memory impairment are the differences in terms of clinical presentations. Clinical findings of 22 patients from 16 families with widespread white matter lesions in the periventricular field in the brain were investigated with molecular genetic findings. Materials and Methods: Clinical examination results and cranial MRI findings are reported, and NOTCH3 and HTRA1 genes are sequenced stepwise by Sanger and next-generation sequencing techniques. Results: Missense changes in epidermal growth factor (EGF)-like domain in the NOTCH3 are found in 18 cases from 14 families. Two different homozygous pathogenic missense and non-sense variants, in the HTRA1 gene, were detected in four patients from two families. The disease onset age was approximately 16 years earlier in cases carrying pathogenic variants located in the encoding region of EGF-like domains 1-6 of NOTCH3. Conclusion: In the NOTCH3 gene with c.382T>C (p.C128R), c.555T>G (p.C185W), and c.1903C>T (p.R635C) and in the HTRA1 gene c.235C>T (p.Q79*) are presented for the first time in this study. Molecular genetic investigation of CADASIL and CARASIL is important to support the clinical diagnosis, determine the inheritance model, provide patient and family counseling, manage disease process, and evaluate possible treatment strategies./ Öz:Amaç: Laküner inmelerin çoğu sporadik olup, hipertansiyon, diyabet, sigara ve kardiyovasküler hastalıklar önemli risk faktörleri arasındadır. Küçük damar hastalıklarının yol açtığı inmeler ise genel olarak ailevi özellik taşıyan dominant ve resesif kalıtım modelleriyle gözlenen tek gen hastalıklarıyla ilişkilidir. En yaygın bilineni NOTCH3 genindeki patojenik varyantlarla ortaya çıkan subkortikal enfarkt ve lökoensefalopati ile giden otozomal dominant serebral arteriyopati (CADASIL) hastalığıdır. Bu hastalığın çok daha nadir bir kliniği ise patojenik HTRA1 gen değişimleri ile gözlenen resesif (CARASIL) formudur. Nörolojik ve kraniyal manyetik rezonans görüntüleme (MRG) bulguları CADASIL’e çok benzer olan CARASIL, moleküler patolojik yolakların farklı olması, hafıza disfonksiyonunun daha ağır seyretmesi, özellikle erkeklerde beklenenden daha erken yaşta başlayan yaygın alopesi görülmesi, bağ dokusunun etkilenmesi ve hastaların önemli bir oranında bel ağrısı yakınmaları gibi özellikleri temelinde CADASIL’den farklı bir klinik seyir izler. Bu çalışmada beyinde periventriküler alanda yaygın ak madde lezyonlarının gözlendiği 16 aileden 22 olgunun klinik bulguları moleküler genetik bulguları eşliğinde araştırıldı. Gereç ve Yöntem: Olguların klinik muayene sonuçları ile kraniyal MRG bulguları raporlandı, NOTCH3 ve HTRA1 genleri kademeli olarak Sanger ve yeni nesil dizi yöntemleriyle incelendi. Bulgular: On dört aileden 18 olguda NOTCH3 geninde epidermal büyüme faktörü (EGF)-like domain bölgesinde sistein dozunu değiştiren heterozigot yanlış anlamlı değişimler ve iki aileden dört hastada HTRA1 geninde, biri anlamsız diğeri yanlış anlamlı tipte iki farklı homozigot patojenik varyant saptandı. NOTCH3’ün 1-6 EGF-like domain yapısını kodlayan bölgede patojenik varyant taşıyan olgularda hastalık bulgularının yaklaşık 16 yıl daha erken başladığı gözlendi. Sonuç: NOTCH3 geninde tespit edilen c.382T>C (p.C128R), c.555T>G (p.C185W), c.1903C>T (p.R635C) ile HTRA1 geninde saptanan c.235C>T (p.Q79*) ilk kez bu çalışmada gösterildi. CADASIL ve CARASIL olgularında moleküler genetik tanı, klinik tanıyı desteklemek, kalıtım modelini belirlemek, hasta ve ailelerine danışmanlık hizmeti sunmak, hastalık sürecini yönetmek ve olası tedavi stratejilerini değerlendirmek için önemlidir.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 Complications of 2-level dynamic stabilization: a correlative clinical and radiological analysis at two-year follow-up on 103 patients(2018) Yılmaz, Atilla; Erbulut, Deniz Ufuk; N/A; Çıplak, Necati Mert; Süzer, Süleyman Tuncer; Şentürk, Salim; Yaman, Onur; Sasani, Mehdi; Öktenoğlu, Bekir Tunç; Özer, Ali Fahir; Doctor; Doctor; Doctor; Doctor; Faculty Member; Faculty Member; Faculty Member; N/A; N/A; N/A; N/A; School of Medicine; School of Medicine; School of Medicine; Koc University Hospital; N/A; 221691; N/A; 219524; 219451; 220898; 1022AIM: To investigate the postoperative complications, such as screw loosening, screw breakage and adjacent segment disease (ASD), in patients who underwent surgery with 2-level dynamic stabilization systems. MATERIAL and METHODS: Postoperative complications, clinical improvements and radiological parameters in patients who underwent surgery using a dynamic system for 2-level lumbar stabilization were retrospectively reviewed. A total of 103 patients with lumbar degenerative spinal instability underwent 2-level dynamic stabilization. Clinical findings were reviewed at 2-year follow-up. Screw breakage and loosening were evaluated during this duration together with clinical findings. ESULTS: Visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were significantly decreased at the four-month evaluation, and they were also decreased at the 1-year follow up and at the 24th postoperative month. ASD was diagnosed in twelve (8 females, 4 males) of the 103 patients in the follow-up radiological and clinical controls. There were 9 screw breakages and 4 screw loosening cases. The complication rate of 2-level dynamic stabilization was high in this study. CONCLUSION: Our results showed that complications (screw loosening or breakage and adjacent segment disease) are not rare after 2-level dynamic stabilization, unlike the acceptable results with the single-level dynamic system. The most probable explanation is that the instrument system behaves more rigidly with every additional segment.Publication Metadata only Dynamic stabilization of the lumbar spine using the Dynesys® system(Turkish Neurosurgical Soc, 2020) Cevik, Orhun Mete; Akyoldaş, Göktuğ; Süzer, Süleyman Tuncer; Sasani, Mehdi; Öktenoğlu, Bekir Tunç; Özer, Ali Fahir; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; 203677; 221691; 219451; 220898; 1022AIM: To present the clinical results in patients with minor instability with "Dynesys (R)"a soft spinal stabilization system. Material and Methods: A total of 83 patients were operated upon and the Dynesys (R) system was applied. Indications for surgery included painful degenerative disc disease, degenerative spondylolisthesis and lumbar canal stenosis. Results: The results for the Dynesys (R) system were satisfactory, and we have calculated the overall complication rate to be 20.4% (n=17), which is in agreement with the literature. Conclusion: The Dynesys (R) dynamic stabilization system effectively protects lumbar motion and achieves lumbar stability in patients with lumbar spinal problems. Our clinical result support literature that Dynesys (R) system is a strong alternative to fusion and instrumentation system in patient with chronic instabilities.
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