6 results on '"Koray, Özduman"'
Search Results
2. Ventricular Meningiomas: Surgical Strategies and a New Finding That Suggest an Origin From the Choroid Plexus Epithelium
- Author
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Mustafa Güdük, Abuzer Güngör, Ahmet Akbaş, M. Necmettin Pamir, Koray Özduman, Murat Şakir Ekşi, and Ayça Erşen Danyeli
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Adolescent ,Intraoperative ultrasonography ,Neurosurgical Procedures ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Choroid Plexus Epithelium ,Humans ,Trigone of urinary bladder ,Medicine ,Aged ,Retrospective Studies ,Tissue microarray ,urogenital system ,business.industry ,Middle Aged ,Treatment Outcome ,Hemiparesis ,IVMS ,030220 oncology & carcinogenesis ,Choroid Plexus ,embryonic structures ,Immunohistochemistry ,Female ,Surgery ,Choroid plexus ,Neurology (clinical) ,medicine.symptom ,Meningioma ,Tomography, X-Ray Computed ,business ,Cerebral Ventricle Neoplasms ,030217 neurology & neurosurgery - Abstract
Background The aim of this study is to share our experiences on a series of 21 patients with intraventricular meningiomas (IVMs). Histopathologic examinations are reviewed in detail and the cell of origin of IVMs is discussed. Methods We retrospectively reviewed 1372 patients with intracranial meningioma who were surgically treated between September 1986 and July 2018. From this cohort, 21 patients with IVM were identified. The clinical, radiologic, surgical, and follow-up records were analyzed. The archival pathologic specimens were reviewed. Tissue microarray blocks were performed from the formalin-fixed, paraffin-embedded samples of all IVM cases, 2 choroid plexus tissue adjacent to the tumors, and 10 extraventricular fibrous meningioma cases selected as control randomly. Immunohistochemical staining with the antibodies S-100, SOX10, NGFR, and OTX2 was performed according to the protocols indicated by the manufacturers. Results Surgical complications included hemiparesis in 1 patient (5%), postoperative seizure in 1 patient (5%), sensorial aphasia in 1 patient (5%), and preexisting headache in 1 patient (5%). Seventeen (81%) of the IVMs had grade I pathology and 4 (19%) had grade II pathology. The immunoprofile of IVMs is identical to the immunoprofile of normal choroid plexus epithelium. Conclusions Transcortical approaches using intraoperative ultrasonography and intraoperative monitoring with avoidance of eloquent cortical areas can achieve good outcomes. Resection of the choroidal attachments should be attempted. Our results indicate that IVMs do not show arachnoid cap cell phenotype and the findings support that IVMs originate from the choroid plexus epithelium or the progenitors of the choroid plexus epithelium.
- Published
- 2019
3. Meningiomas Display a Specific Immunoexpression Pattern in a Rostrocaudal Gradient: An Analysis of 366 Patients
- Author
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Ayça Erşen Danyeli, Ege Ülgen, Pınar Kuru Bektaşoğlu, Deniz Baycin Hizal, M. Necmettin Pamir, Koray Özduman, M. Aydın Sav, and Özge Can
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Adolescent ,CD34 ,Meningioma ,Young Adult ,03 medical and health sciences ,Meninges ,0302 clinical medicine ,Cranial vault ,Progesterone receptor ,Meningeal Neoplasms ,otorhinolaryngologic diseases ,medicine ,Humans ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Middle Aged ,medicine.disease ,Immunohistochemistry ,Survival Analysis ,Skull ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Embryology ,Female ,Surgery ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Secretory Meningioma ,Follow-Up Studies - Abstract
Background Meningiomas are heterogeneous, with differences in anatomical, histopathological, and clinical characteristics. Such spatial variability in meningioma biology is thought to result from differences in the expression of critical developmental regulators. We hypothesized that the variability in meningioma biology would follow gradients such as in embryology and tested a cohort of 366 meningiomas for histopathological and immunohistochemical gradients. Methods The medical records from 366 patients treated for meningiomas from 2003 to 2016 were retrospectively analyzed for age, gender, anatomical localization, recurrence-free survival, overall survival, histopathological diagnosis, and immunohistochemistry findings for 6 markers: epithelial membrane antigen (EMA), progesterone receptor (PR), CD34, S100, p53, and Ki-67 labeling index. Results EMA, PR, S100, p53, and CD34 were expressed in 94%, 73%, 49%, 26%, and 23% of the tumors, respectively. p53 expression correlated positively with Ki-67 and World Health Organization (WHO) grade (rτ = 0.31 and rτ = 0.4, respectively). PR positivity correlated inversely with S100, p53, Ki-67, and WHO grade (rτ = −0.19, rτ = −0.14, rτ = −0.15, and rτ = −0.16, respectively). All secretory meningiomas were positive for EMA and PR and negative for S100, and this pattern exhibited a rostrocaudal gradient. The overall proportion of EMA+PR+S100− cases was significantly lower in the cranial vault (30.3%) than in the skull base (45.89%; P = 0.021). The proportion of WHO grade II-III tumors was greater in cranial vault than in skull base meningiomas. Conclusions Unsupervised methods detected an association between the anatomical location and tumor biology in meningiomas. Unlike the categorical associations that former studies had indicated, the present study revealed a rostrocaudal gradient in both the cranial vault and the skull base, correlating with human developmental biology.
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- 2019
4. Mutations and copy number alterations in diffuse gliomas are shaped by different mechanisms
- Author
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Kaya Bilguvar, Şirin Yüksel, Cengiz Yakicier, Cemaliye B Akyerli, S. Karacan, Osman Ugur Sezerman, Tarik Tihan, Mustafa Pamir, Özge Can, Umut Gerlevik, Koray Özduman, Ayça Erşen-Danyeli, and Ege Ülgen
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Cancer Research ,Oncology ,business.industry ,Cancer research ,Medicine ,business - Published
- 2020
5. Sporadic Spinal Hemangioblastomas Can be Effectively Treated by Microsurgery Alone
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M. İmre Usseli, Koray Özduman, H Ibrahim Sun, Serdar Özgen, and M. Necmettin Pamir
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Adult ,Male ,Microsurgery ,medicine.medical_specialty ,Cord ,medicine.medical_treatment ,Neurosurgical Procedures ,Young Adult ,Lumbar ,Hemangioblastoma ,medicine ,Humans ,Syrinx (medicine) ,Cyst ,Spinal Cord Neoplasms ,Karnofsky Performance Status ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Cervical Cord ,Magnetic resonance imaging ,Middle Aged ,Spinal cord ,medicine.disease ,Surgery ,medicine.anatomical_structure ,Spinal Cord ,Female ,Neurology (clinical) ,business ,Follow-Up Studies - Abstract
Objective Clinical characteristics and management of hemangioblastomas of the spinal cord associated with von Hippel-Lindau syndrome have been extensively covered in the literature. This report aims to analyze the characteristics and surgical treatment results of sporadic spinal hemangioblastomas (SSHB). Methods This is a retrospective analysis of 14 patients with SSHB (8 men and 6 women) operated on during a span of 23 years. The median age was 41.5 years (24–70 years). von Hippel Lindau syndrome was excluded by imaging in all patients. The median follow-up was 4 years (1–23 years). We also conducted a meta-analysis of all 271 SSHB cases reported in the English-speaking language literature from 1967 to 2011. Results Nine (64.3%) lesions were cervical, 3 (28.5%) were thoracic, and 1 (7.1%) was lumbar. Eight (57.1%) tumors were dorsal intramedullary, 4 (28.6%) were exophytic, 1 (7.1%) was intradural extramedullary, and 1 (7.1%) was completely extradural. Diffuse segmental cord enlargement was present in 7 patients (50%) and a cyst/syrinx was present in 7 (50%). These 14 patients underwent 15 operations, and gross total resection was achieved in all operations. There was no mortality. Symptoms improved after 8 (53.3%) of 15 operations, remained the same after 5 (33.3%), and worsened after 2 (13.3%). The mean Karnofsky performance score improved from 79.3 (± 17.5) to 87.3 (± 12.2) after 6 months of follow-up. There was one recurrence 15 years after magnetic resonance imaging confirmed total resection. Conclusions The SSHBs occur most often in the upper spinal cord. Excellent surgical results and long-term outcome can be achieved using microsurgery alone with only rare recurrences.
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- 2014
6. The galenic venous system: Surgical anatomy and its angiographic and magnetic resonance venographic correlations
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Koray Özduman, M. Necmettin Pamir, Turker Kilic, Safiye Çavdar, and M. Memet Özek
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Adult ,Cerebral veins ,medicine.medical_specialty ,Pineal Gland ,Patient Care Planning ,Magnetic resonance angiography ,Corpus Callosum ,Cohort Studies ,Cerebellum ,Image Processing, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Vein ,Basal vein ,medicine.diagnostic_test ,business.industry ,Angiography, Digital Subtraction ,General Medicine ,Digital subtraction angiography ,Middle Aged ,Cerebral Veins ,Temporal Lobe ,medicine.anatomical_structure ,medicine.vein ,Case-Control Studies ,Child, Preschool ,Angiography ,cardiovascular system ,Occipital Lobe ,Radiology ,Internal Occipital Vein ,business ,human activities ,Lower limbs venous ultrasonography ,Magnetic Resonance Angiography - Abstract
Objective: This study aims at evaluating the adequacy of digital subtraction angiography and magnetic resonance venography in imaging of the galenic venous system for surgical planning of approaches to the pineal region. Anatomical dissections were carried out in 10 cadavers of several age groups and these were compared to imaging findings in 10 living subjects. Methods: The presence or absence of 10 predetermined veins or vein groupings belonging to the galenic venous system were prospectively analyzed in 10 cadaver dissections and imaging findings of 10 age matched human subjects. The studied vessels were the vein of galen, the internal cerebral veins, both basal vein of Rosenthals, internal occipital vein, occipitotemporal veins, precentral cerebellar veins, tectal veins, pineal veins, superior vermian veins (including superior cerebellar veins (SCVs)) and posterior pericallosal veins. Each of the subjects had both digital subtraction angiography and magnetic resonance venography studies performed. Diagnostic digital subtraction angiography was performed using the transfemoral route and the venous phase was used for the study. Magnetic resonance venography was performed in 1.5 T MRI equipment using the 2D-TOF sequence. All studies were reported to be normal. Results: There was wide variation in the anatomy of the galenic venous system. There were interpersonal, intrapersonal and age related variations. Both the digital subtraction angiography and the magnetic resonance venography were efficient at demonstrating large veins. However, smaller veins were less readily demonstrated in either study. The general sensitivities of the digital subtraction angiography and the magnetic resonance venography for the galenic venous system were 45.5% and 32.5%, respectively. Surgically important veins were missed in most studies. Conclusions: Anatomically, the galenic venous system is highly variable. This variability is caused by interpersonal, intrapersonal and age related differences and causes each individual galenic venous system to be unique. Therefore, modern neurosurgical procedures require anatomical information on individual differences. Current radiological methods of digital subtraction angiography and magnetic resonance venography fail short of providing the necessary information. New and more sophisticated MRI technology may fulfill this need.
- Published
- 2005
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