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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
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Publication Metadata only Anatomical parameters of percutaneous, minimally invasive, direct intralaminar pars screw fixation of spondylolysis(Elsevier Science Inc, 2024) Gudu, Burhan Oral; Aydin, Ahmet Levent; Mercan, Necip Engin; Dilbaz, Suna; Cirak, Musa; N/A; Özer, Ali Fahir; School of Medicine- OBJECTIVE: To investigate the anatomical parameters of the ideal screw trajectory for percutaneous intralaminar screw fixation of a pars defect in lumbar spondylolysis using computed tomography scans. - METHODS: Using advanced radiological software, the ideal intralaminar screw trajectory was determined. The anatomical parameters of this trajectory were analyzed using a total of 80 single-level lumbar tomography scans in patients with spondylolysis at the lumbar 4 vertebrae and lumbar 5 vertebrae levels. The ideal intralaminar screw trajectory started from the inferolateral edge of the lamina and was between the intralaminar region, pars defect, and defective pars neck and pedicle. Along this trajectory, the skin-lamina distance, intralaminar screw length, isthmic lamina length and width, defective pars neck width, lateral entry distance of the screw to the center of the spinous process, and sagittal and coronal screw application angles were analyzed. - RESULTS: When comparing the lumbar 4 vertebrae and lumbar 5 vertebrae parameters, the mean skin-to-lamina distances were 11-9 cm ( P = 0.000), intralaminar screw lengths 3.5-3.6 cm ( P = 0.067), isthmic lamina lengths 22 cm ( P = 0.698), mid-lamina widths 1-1 cm ( P = 0.941), defective pars neck widths 1-1 cm ( P = 0.674), screw lateral entry distances according to the spinous process 1-1.5 cm ( P = 0.000), sagittal screw angles 45 degrees-45 degrees ( P = 0.870), and coronal screw angles 10 degrees-20 degrees ( P = 0.000), respectively. There were no differences based on age and gender ( P < 0.05). - CONCLUSIONS: Percutaneous intralaminar rigid screw fixation of a pars defect in spondylolysis provides minimally invasive, low-profile instrumentation. In spondylolysis, a screw length of 3-4 cm and a screw diameter of 45 mm may be sufficient for pars fixation with intralaminar screws.Publication Metadata only Association of TaqI (rs731236) polymorphism of vitamin D receptor gene with lumbar degenerative disc disease(Elsevier Science Inc, 2024) Serifoglu, Luay; Yilmaz, Seda Gulec; Karaaslanli, Abdulmutalip; Etli, Mustafa Umut; Ozdogan, Selcuk; N/A; Düzkalır, Ali Haluk; N/A; Koç University Hospital- BACKGROUND: Lumbar degenerative disc disease (LDDD) significantly contributes to low back pain, with a complicated etiology involving genetic and environmental facts. The aim of study was to investigate the association between the Taq I (rs731236) polymorphism of the vitamin D receptor ( VDR ) gene with LDDD. - METHODS: In total, 248 patients with symptomatic LDDD and 146 control subjects were examined. The evaluation of clinical features of patients with LDDD comprised radiodiagnostic magnetic resonance imaging, neurologic examinations, pain scores including the visual analog scale (VAS), and disability investigation with Oswestry Disability Index (ODI). Genotyping of the VDR gene polymorphism was conducted using polymerase chain reaction ebased methods.- RESULTS: Individuals of the LDDD group who were VDR TaqI AA genotype carriers were significantly greater than the other group ( P = 0.014), whereas those with GG genotype were significantly lower ( P = 0.028) in the patient group. In addition, VAS and ODI scores were significantly lower in the GG genotype carrier group, whereas AA genotype carriers had the greatest scores ( P = 0.004). Carrying the G allele decreased the risk of LDDD 1.7 times ( P = 0.014) and carrying the A allele enhanced the risk 1.8 times ( P = 0.028). Moreover, G-allele carriers had significantly lower VAS ( P = 0.002) and ODI scores ( P < 0.0001). - CONCLUSIONS: VDR Taq I (rs731236) GG genotype and G allele have protective potential, whereas the AA genotype and A allele are risk factors for LDDD. The findings reveal a statistically significant association of the Taq I (rs731236) polymorphism of VDR gene polymorphism with LDDD. This result highlights the potential role of genetic factors in developing LDDD and suggests avenues for future research in genetic screening and personalized treatment strategies.Publication Metadata only The relationship between inflammatory processes and apoptosis in lumbar disc degeneration(Elsevier Inc., 2024) Cetintas, Semih Can; Akyol, Sibel; Alizada, Orkhan; Tahmazoglu, Burak; Hanci, Murat; Isler, Cihan; N/A; Akgün, Mehmet Yiğit; N/A; Koç University HospitalObjective: Degenerative Disc Disease (DDD) is a common health problem in the population. There are recent studies focusing on relationship between DDD and immunological factors. However, there is still a lack of data on the role of apoptosis in DDD pathophysiology. Therefore, we aimed to investigate the relationship between Modic-type changes and the apoptosis in DDD. Materials and Methods: Ninety adult male patients who presented with low back and/or radicular pain and were operated on due to lumbar disc herniation were included. Three groups were formed based on Modic type degeneration observed on magnetic resonance imaging. Specific parameters involved in the intrinsic and extrinsic pathways of apoptosis were assessed in excised disc materials using the enzyme-linked immunosorbent assay method. Results: All three groups formed according to Modic degeneration types were homogenous in all variances. Cytochrome-C was significantly decreased only in the Modic type-3 group, whereas Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor-1, B-Cell Lymphoma-2 (Bcl-2) Homologous Antagonist Killer-1, Direct Inhibitor of Apoptosis-Binding Protein with Low Pi, and Bcl-2 Associated X Apoptosis Regulator levels were significantly different in both Modic type-2 and -3 groups. However, BH3 interacting domain death agonist and Bcl-2 levels were similar across all groups. Conclusions: In conclusion, this study suggests that Direct Inhibitor of Apoptosis-Binding Protein with Low Pi, cytochrome - c, Bcl-2 Associated X Apoptosis Regulator, Bcl-2 Homologous Antagonist Killer-1, and Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor-1proteins play important roles in the development and progression of DDD and are correlated with Modic types. Further studies are needed to explore the potential therapeutic role of inhibiting these apoptotic proteins in DDD. © 2024 Elsevier Inc.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 Is the modular dynamic system as effective as classical dynamic systems in long segment dynamic thoracolumbar stabilization?(Turkish Neurosurgical Society, 2024) N/A; Günerbüyük, Caner; Akgün, Mehmet Yiğit; Özer, Ali Fahir; School of Medicine; Koç University HospitalAIM: To evaluate the outcomes of dynamic stabilization in the multilevel degenerative spondylotic spine, and to compare the two dynamic systems (Dynesys (R) and Orthrus (R)) to reveal the increasing role of dynamic systems in the management of the degenerative spine. MATERIAL and METHODS: A total of 74 patients who received dynamic stabilization for degenerative pathologies were retrospectively analyzed. Demographic details: preoperative data including neurological status, pain scores, and radiology; and intraoperative data including blood loss, duration of surgery, complications, and postoperative data including the neurologic status, duration of hospital stay, and pain scores were examined. RESULTS: Patients in both groups showed statistically significant improvements in their Visual Analog Scale and Oswestry Disability Index scores. Significant corrections of thoracic kyphosis (T2 -T12), the sagittal vertical axis, and T10 -L2 thoracolumbar kyphosis were obtained in our cohort (p<0.05). A total of 4 patients received revision surgery due to screw loosening. Patients were discharged after 3-4 days and mobilized on the first postoperative day. CONCLUSION: We did not experience any serious issues in terms of stabilization in the cases in which we employed both systems. Our patients' clinical results were satisfactory in both systems. Existing systems can be used safely even in long -segment stabilization surgeries.Publication Metadata only Transient ageusia and dysgeusia following thalamic cyst drainage(Turkish Neurosurgical Society, 2024) N/A; Nokay, Aziz Emre; Erden, Mert Emre; Samancı, Mustafa Yavuz; Peker, Selçuk; School of MedicineTaste consists of sensation and perception. Specific neural structures transmit a stimulus from the taste buds to the gustatory cortex to generate taste sensation. Any disruption of this pathway, whether it affects sensation or perception, can result in taste disorders. Stereotactic procedures involving the thalamus may result in gustatory complications. A 41-year-old female patient who underwent stereotactic drainage of a thalamic cyst suffered transient ageusia. Subsequently, she developed metallic taste perception. When her stereotactic plan was re-evaluated, it was noted that the posteromedial ventral thalamus nucleus was in the path of the needle tract and the needle had passed through it. Follow-up was recommended and her symptoms completely resolved within 2 months following surgery. Modern imaging techniques allow for the visualization of neural structures related to the sense of taste. Additionally, care must be taken when planning stereotactic procedures for such lesions.Publication 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 The past, present, and future statuses of formerly classified "atypical pituitary adenomas": a clinicopathological assessment of 101 cases in a cohort of more than 1,000 pure endoscopically treated patients in single center(Thieme Medical Publ Inc, 2021) Bal, Ercan; Ayhan, Selim; Soylemezoglu, Figen; Berker, Mustafa; N/A; Kulaç, İbrahim; Faculty Member; School of Medicine; Koç University Hospital; 170305Objective This study was aimed to assess the clinical aggressiveness of pituitary neoplasms that were previously defined as atypical adenomas. Methods A total of 1,042 pituitary adenomas were included in the study and 101 of them were diagnosed as atypical adenoma. Demographic characteristics, radiological evaluations, and clinical information were obtained from a computer-based patient database. Cases were categorized as atypical or typical using the criteria listed in 2004 Classification of Tumors of Endocrine Organs. Results The cure and reoperation rates did not show any statistically significant difference between the typical and atypical adenomas. However, a higher K (i) -67 labeling index was found to be associated with a higher rate of reoperation ( p =0.008) in atypical adenomas. of note, cavernous sinus invasion or parasellar extension was found to be associated with lower cure rates in patients with atypical pituitary adenomas ( p <0.001 and p =0.001, respectively). Conclusion Although atypical pituitary adenomas are known to be more invasive, this study demonstrated that the reoperation and cure rates are the same for typical and atypical adenomas. Our findings advocate for omitting the use of atypical adenoma terminology based solely on pathological evaluation. As stated in the 4th edition of the World Health Organization (WHO) classification, accurate tumor subtyping, evaluation of proliferation by means of mitotic count and K (i) -67 labeling index, and radiological and intraoperative assessments of tumor invasion should be taken into consideration in the management of such neoplasms.Publication Metadata only A multicenter international study to evaluate different aspects of relationship between MS and pregnancy(Sage, 2019) Zakaria, M.; Alroughani, R.; Moghadasi, A. N.; Terzi, M.; Sen, S.; Koseoglu, M.; Efendi, H.; Soysal, A.; Gozubatik-Celik, G.; Ozturk, M.; Sahraian, M.; Akinci, Y.; Kaya, Z. E.; Saip, S.; Siva, A.; N/A; Department of Industrial Engineering; Altıntaş, Ayşe; Gönen, Mehmet; Faculty Member; Faculty Member; Department of Industrial Engineering; School of Medicine; College of Engineering; 11611; 237468N/APublication 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.