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Publication Metadata only A case of drop foot due to piriformis syndrome(Springer Heidelberg, 2015) Yıldırım, Pelin; Güler, Tuba; Özer, Tülay; Gündüz, Osman Hakan; N/A; Mısırlıoğlu, Tuğçe Özekli; Doctor; N/A; Koç University Hospital; 175999N/APublication Metadata only A genetic cause for intractable seizures: atypical Gaucher disease with a novel pathological variant(WILEY, 2024) Üçem, Selen; Avcı, Şahin; Gürses, Rabia Candan; School of Medicine; Koç University HospitalPublication Metadata only A new lumbar fixation device alternative to pedicle-based stabilization for lumbar spine: in vitro cadaver investigation(Taylor & Francis, 2020) Gomleksiz, Cengiz; Erbulut, Deniz Ufuk; Can, Halil; Kodigudla, Manoj Kumar; Kelkar, Amey, V; Kasapoglu, Eser; Ozer, Ali Fahir; Goel, Vijay K.; Özer, Ali Fahir; Faculty Member; School of Medicine; 1022Context: To evaluate the stability provided by a new bilateral fixation technique using an in vitro investigation for posterior lumbar segmental instrumentation. Design: Experimental cadaver study. In this study, we propose an alternative technique for a posterior lumbar fixation technique called "inferior-oblique transdiscal fixation" (IOTF). Setting: Study performed at Engineering Center for Orthopedic Research Exellence (ECORE) in Toledo University-Ohio. Participants: Six human lumbar cadaveric specimen used in this study. Interventions: In this study, we propose an alternative technique for a posterior lumbar fixation technique called "inferior-oblique transdiscal fixation" (IOTF). As a novel contribution to the classical technique, the entry point of the screw is the supero-lateral point of the intersecting line drawn between the corpus and the pedicle of the upper vertebra. This approach enables the fixation of two adjacent vertebrae using a single screw on each side without utilizing connecting rods. Outcome Measures: Flexion (Flex), extension (Ext), right and left lateral bending (LB & RB), and right and left axial rotation (LR & RR), and the position data were captured at each load step using the Optotrak motion measurement system and compared for IOTF and posterior transpedicular stabilization. Results: The Posterior stabilization system (PSS) and IOTF significantly reduced the ROM of L4-L5 segment compared to intact segment's ROM. During axial rotation (AR) IOTF fused index segment more than PSS. Besides this, addition of transforaminal lumbar interbody fusion (TLIF) cage improved the stabilization of IOTF system during flexion, extension and lateral bending. Whereas, PSS yielded better fusion results during extension compared to IOTF with and without interbody fusion cages. Conclusions: We hypothesized that the new posterior bilateral system would significantly decrease motion compared to the intact spine. This cadaver study showed that the proposed new posterior fusion technique IOTF fused the index segment in a similar fashion to the classical pedicle screw fusion technique.Publication Metadata only A novel pathogenic variant in the 3ʹ end of the AGTPBP1 gene gives rise to neurodegeneration without cerebellar atrophy: an expansion of the disease phenotype?(Springer, 2021) Turay, Sevim; Eroz, Recep; N/A; Başak, Ayşe Nazlı; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; 1512Childhood-onset neurodegeneration with cerebellar atrophy (CONDCA) is a recently described form of the large group of infantile hereditary lower motor neuron diseases (Teoh et al. 2017), resulting from biallelic damaging variants in the AGTPBP1 gene, first described by Shashi et al. in EMBO J 37(23):e100540, 2018. AGTPBP-related neurodegeneration is a severe neurodevelopmental disorder that progresses with global developmental delay and intellectual disability, often accompanied with peripheral nerve damage and lower motor degeneration and a fatal course in the early years of life. The encoded protein is ATP/GTP-Binding Protein1, also known as cytosolic carboxypeptidase 1 (CCP1) or nervous system nuclear protein induced by axotomy (NNA1). Here we report a consanguineous family with four offspring, two of whom are affected. The index patient is a 21-month-old male with global developmental delay and hypotonia. The proband's 17-year-old sister, diagnosed with cerebral palsy, had severe hypotonia accompanied by motor and cognitive retardation. WES analysis revealed a novel homozygous c.3293G > A variant in the AGTPBP1 gene with high pathogenicity scores. Targeted Sanger sequencing confirmed the variant in both affected children and in heterozygous form in the parents. The affected siblings present with hypotonia and motor and cognitive retardation, in line with the studies previously reported. However, in our patients, no signs of cerebellar atrophy in cranial MRI were present, so the acronym CONDCA is not applicable; lower motor neuron findings were also absent. The matching and distinguishing aspects of our patients will add to the present literature and expand our understanding of this rare genetic neurodegenerative disease of early childhood.Item Metadata only A plain language summary on the effectiveness of cladribine tablets compared with other oral treatments for multiple sclerosis: results from the MSBase registry(Future Medicine Ltd, 2023) 0000-0002-8524-5087; Spelman, Tim; Ozakbas, Serkan; Alroughani, Raed; Terzi, Murat; Hodgkinson, Suzanne; Laureys, Guy; Kalincik, Tomas; Van der Walt, Anneke; Yamout, Bassem; Lechner-Scott, Jeannette; Soysal, Aysun; Kuhle, Jens; Sanchez-Menoyo, Jose Luis; Morgado, Yolanda Blanco; Spitaleri, Daniele L. A.; van Pesch, Vincent; Horakova, Dana; Ampapa, Radek; Patti, Francesco; Macdonell, Richard; Al-Asmi, Abdullah; Gerlach, Oliver; Oh, Jiwon; Tundia, Namita; Wong, Schiffon L.; Butzkueven, Helmut; MSBase Study Grp; N/A; Altıntaş, Ayşe; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; 11611What is this summary about?Patient registries contain anonymous data from people who share the same medical condition. The MSBase registry contains information from over 80,000 people living with multiple sclerosis (MS) across 41 countries.Using information from the MSBase registry, the GLIMPSE (Generating Learnings In MultiPle SclErosis) study looked at real-life outcomes in 3475 people living with MS who were treated with cladribine tablets (Mavenclad((R))) compared with other oral treatments.What were the results?Results showed that people treated with cladribine tablets stayed on treatment for longer than other treatments given by mouth. They also had fewer relapses (also called flare ups of symptoms) than people who received a different oral treatment for their MS.What do the results mean?The results provide evidence that, compared with other oral treatments for MS, cladribine tablets are an effective medicine for people living with MS.Publication Metadata only Anatomic variations of the human falx cerebelli and its association with occipital venous sinuses(Taylor & Francis, 2021) Solmaz, Bilgehan; Dalçık, Hakkı; Aydoğmuş, Evren; Kara, Erdoğan; Aslıyüksek, Hızır; N/A; Çavdar, Safiye; Tanış, Özgül; Güler, Orhan Ulaş; Altunkaya, Leyla; Faculty Member; Undergraduate Student; Undergraduate Student; Undergraduate Student; School of Medicine; School of Medicine; School of Medicine; School of Medicine; 1995; N/A; N/A; N/APurpose Human falx cerebelli is an important anatomical structure in regard to its relations with venous structures during infratentorial approach to reach cerebellar tumors, vascular malformations, traumatic hemorrhage and Chiari malformations. The present study aim to describe the different types of variations of the falx cerebelli, its morphological features and its association with occipital venous sinuses. Method In this study 49 dura mater was obtained from the Institution of Forensic Medicine. The length, width and the depth of the falx cerebelli were measured using a digital compass. The data obtained were statistically analyzed in relation to age and gender. The relations of the falx cerebelli with the occipital sinus was documented. Histological sections from the falx cerebelli were stained with Hematoxylin Eosin to evaluate the fine structure. Results Among the 49 falx cerebelli examined 36 (73.5%) were classified as normal. The average length, width and depth of the normal falx cerebelli was 3.7, 1.0 and 0.4 cm respectively. of the 49 falx cerebelli in 1 (2%) case it was absent, in 5 cases (10.2%) duplicate, in 5 cases (10.2%) triplicate, in 1 (2%) case quadruplets and in 1 case (2%) it was five-folded. The proximal and the distal attachments of the falx cerebelli showed 3 types of variations; both attachments triangular, the proximal attachments triangular and the distal ramified and distal attachments triangular and the proximal attachments ramified. The drainage of the occipital sinus of falx cerebelli with variations were evaluated. The increased number of falx cerebelli highly corresponded with the increased number of occipital sinus. Conclusions The dural-venous variation in the posterior cranial fossa can be problematic in various diagnostic and operative procedures of this region. Neurosurgeons should be aware of such variations, as these could be potential sources of haemorrhage during the midline suboccipital and infratentorial approaches.Publication Metadata only Can TRIF/TICAM-1 dependent pathway be target pathway in lumbar intervertebral disc degeneration?(Turkish Neurosurgical Society, 2023) ALIZADA, Orkhan; AKYOL, Sibel; OZLEN, Fatma; CETINTAS, Semih Can; TURK, Okan; HANCI, Murat; N/A; Akgün, Mehmet Yiğit; N/A; Koç University HospitalAIM: To elucidate the role of the TIR-domain-containing adaptor-inducing interferon-β (TRIF) dependent pathway in intervertebral disc degeneration (IVD). MATERIAL and METHODS: A total of adult male patients with low back pain (LBP) (+/- radicular pain) were further evaluated by magnetic resonance imaging (MRI) with surgical indication for microscopic lumbar disc herniation (LDH). Preoperatively, patients were classified according to Modic Changes (MC), nonsteroidal anti-inflammatory drugs (NSAIDs) use, and the presence of radicular pain in addition to the LBP. RESULTS: The age of the 88 patients ranged from 19 to 75 years (mean: 47.3 ± 19.6 years). Twenty eight of the patients were evaluated as MC I (31.8%), 40 as MC II (45.4%), and 20 as MC III (22.7%). The majority of patients (81.8%) had radicular LBP, while 16 patients (18.1%) had only LBP. Predominantly, 55.6% of all patients were taking NSAIDs. Levels of all adaptor molecules were highest in the MC I group and lowest in the MC III group. The levels of IRF3, TICAM1, TICAM2, NF-kB p65, TRAF6, and TLR4 were significantly increased in the MC I group compared to the MC II and MC III groups. The variations of the individual adaptor molecules showed no statistically significant difference in the use of NSAIDs and radicular LBP. CONCLUSION: As a result of the impact assessment, the current study clearly demonstrated for the first time that the TRIF-dependent signalling pathway plays a crucial role in the degeneration process in human lumbar intervertebral disc specimens. © 2023. All Right Reserved.Publication Metadata only Case series and descriptive cohort studies in neurosurgery: the confusion and solution(Springer, 2014) Esene, Ignatius N.; Ngu, Julius; El Zoghby, Mohamed; Sikod, Anna M.; Kotb, Ali; Dechambenoit, Gilbert; El Husseiny, Hossam; N/A; Solaroğlu, İhsan; Faculty Member; School of Medicine; 102059Case series (CS) are well-known designs in contemporary use in neurosurgery but are sometimes used in contexts that are incompatible with their true meaning as defined by epidemiologists. This inconsistent, inappropriate and incorrect use, and mislabeling impairs the appropriate indexing and sorting of evidence. Using PubMed, we systematically identified published articles that had "case series" in the "title" in 15 top-ranked neurosurgical journals from January 2008 to December 2012. The abstracts and/or full articles were scanned to identify those with descriptions of the principal method as being "case series" and then classified as "true case series" or "non-case series" by two independent investigators with 100 % inter-rater agreement. Sixty-four articles had the label "case series" in their "titles." Based on the definition of "case series" and our appraisal of the articles using Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines, 18 articles (28.13 %) were true case series, while 46 (71.87 %) were mislabeled. Thirty-five articles (54.69 %) mistook retrospective (descriptive) cohorts for CS. CS are descriptive with an outcome-based sampling, while "descriptive cohorts" have an exposure-based sampling of patients, followed over time to assess outcome(s). A comparison group is not a defining feature of a cohort study and distinguishes descriptive from analytic cohorts. A distinction between a case report, case series, and descriptive cohorts is absolutely necessary to enable the appropriate indexing, sorting, and application of evidence. Researchers need better training in methods and terminology, and editors and reviewers should scrutinize more carefully manuscripts claiming to be "case series" studies.Publication Metadata only Cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS): an important cause of late-onset ataxia with unique clinical features(Springer Heidelberg, 2022) Çakar, Arman; Şahin, Erdi; Tezel, Seden; Candayan, Ayşe; Samancı, Bedia; Battaloğlu, Esra; Bilgiç, Başar; Hanağası, Haşmet; Durmuş, Hacer; Parman, Yeşim; N/A; Başak, Ayşe Nazlı; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; 1512Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) is a late-onset, slowly progressive disorder characterized by cerebellar ataxia, sensory neuropathy and bilateral vestibulopathy. Recently, a biallelic intronic AAGGG repeat expansion, (AAGGG)(exp), in the Replication Factor C1 (RFC1) gene was identified as the cause of this disorder. In this study, we describe the phenotypic features of five patients from five different families diagnosed as CANVAS. The mean age at onset was 49.00 +/- 9.05 years (between 34 and 56 years) and the most frequent presenting symptom in CANVAS was gait ataxia, followed by sensory disturbances. Persistent coughing was prominent in three patients, and it preceded the onset of ataxia and sensory symptoms in two patients. Parental consanguinity was present in three patients. Two patients showed symptoms or signs suggesting autonomic involvement. Sural nerve biopsy revealed axonal neuropathy in two patients. The mean age at onset was 49.00 +/- 9.05 years (between 34 and 56 years) and the most frequent presenting symptom in CANVAS was gait ataxia, followed by sensory disturbances. Persistent coughing was prominent in three patients, and it preceded the onset of ataxia and sensory symptoms in two patients. Parental consanguinity was present in three patients. Two patients showed symptoms or signs suggesting autonomic involvement. Sural nerve biopsy revealed axonal neuropathy in two patients. Our study describes clinical findings, histopathological features and diagnostic clues of CANVAS from Turkey, a country with a high consanguineous marriage rate. Repeat expansion in the RFC1 gene should be considered in all cases with late-onset ataxia, especially when sensory disturbances, vestibular involvement and persistent coughing coexist.Publication Metadata only Cerebellar cognitive-affective syndrome preceding ataxia associated with complex extrapyramidal features in a Turkish SCA48 family(Springer, 2020) Kaya-Güleç, Zeynep Ece; Genç, Gencer; N/A; Palvadeau, Robin Jerome; Şimşir, Gülşah; Vural, Atay; Çakmak, Özgür Öztop; Aygün, Murat Serhat; Falay, Fikri Okan; Başak, Ayşe Nazlı; Ertan, Fatoş Sibel; Researcher; Master Student; Faculty Member; Faculty Member; Teaching Faculty; Teaching Faculty; Faculty Member; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; Graduate School of Sciences and Engineering; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; N/A; N/A; 182369; 299358; 291692; 246484; 1512; 112829SCA48 is a novel spinocerebellar ataxia (SCA) originally and recently characterized by prominent cerebellar cognitive-affective syndrome (CCAS) and late-onset ataxia caused by mutations on the STUB1 gene. Here, we report the first SCA48 case from Turkey with novel clinical features and diffusion tensor imaging (DTI) findings, used for the first time to evaluate a SCA48 patient. A 65-year-old female patient with slowly progressive cerebellar ataxia, cognitive impairment, behavioral changes, and a vertical family history was evaluated. Following the exclusion of repeat expansion ataxias, whole exome sequencing (WES) was performed. Brain magnetic resonance imaging (MRI), including DTI, and single-photon emission computed tomography (SPECT) were used to study the primarily affected tracts and regions. WES revealed the previously reported heterozygous truncating mutation in ubiquitin ligase domain of STUB1 (ENST00000219548:c.823_824delCT, ENSP00000219548:p.L275Dfs*16) leading to a frameshift. Patient's cognitive status was compatible with CCAS. Novel clinical features different from the original report include later onset chorea, dystonia, general slowness of movements, apraxia, and palilalia, some of which have been recently reported in two families with different STUB1 mutations. CCAS is a prominent and often early feature of SCA48 which may be followed years after the onset of the disease by other complex neurological signs and symptoms. DTI may be helpful for demonstrating the cerebello-frontal tracts, involved in CCAS-associated SCA48, the differential diagnosis of which may be challenging especially in its early years.