Aslan Guzel
Dicle University
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Publication
Featured researches published by Aslan Guzel.
British Journal of Neurosurgery | 2005
Mehmet Tatli; Aslan Guzel; Adnan Ceviz; Özen Karadağ
Posterior epidural migration of free disc fragments is rare, and posterior migration of the free fragments causing cauda equina syndrome is exceptionally rare. This report describes a 53-year-old man with disc fragment extrusion at the levels of L3–4 and a 54 -year-old man with disc fragment extrusion at L5–S1 intervertebral space. The patients responded well to the operative therapy with complete relief of the symptoms. The pathological examination confirmed that the specimen was a degenerated intervertebral disc. Early surgery should be the first choice of therapy in patients with large posteriorly migrated sequestered disc fragments, to prevent severe neurological deficits such as cauda equina and conus medullaris syndromes.
Pediatric Neurosurgery | 2007
Aslan Guzel; Mehmet Tatli; Murad Bavbek
The authors report a 7-year-old girl who presented with progressive quadriparesis which had started a month before admission. Magnetic resonance imaging of the spine revealed an intramedullary cystic lesion extending from C2 to C4. After performing a C2–5 laminectomy, the cyst was drained and anatomically fenestrated with the subarachnoid space by a 1-cm vertical median myelotomy without using a stent. The histopathological findings revealed arachnoid cyst. In the first month after operation, the neurological deficits disappeared gradually, except for a slight left upper paresis. Cervical spinal intramedullary arachnoid cyst is extremely rare and should be considered in the differential diagnosis of intramedullary cystic lesions in childhood. Recovery is possible after subtotal excision and fenestration of the cyst to allow communication with the subarachnoid space even if neurological deficits are present for a long time.
Brain Research | 2007
Mehmet Tatli; Aslan Guzel; Göksel Kızıl; Vatan Kavak; Murat Yavuz; Murat Kızıl
Both maternal protein malnutrition and intrauterine growth restriction (IUGR) have deleterious effects on brain development, but a comparison of these effects has not been previously reported. The objectives of this study were to investigate and compare the effects of both factors on the oxidative status of the central nervous system (CNS), including the spinal cord, in offspring rats. We evaluated various parameters of oxidative status and antioxidant enzyme activities of superoxide dismutase and catalase (CAT) in different regions of the CNS from 60-day-old rats subjected to prenatal and postnatal protein restrictions [middle protein restriction 12%, severe protein restriction (SPR) 4%] or IUGR produced by uterine artery ligation. Furthermore, we compared these study groups to each other and to control rats fed an isocaloric 24% protein diet. Results were analyzed using one-way ANOVA followed by Tukeys post hoc test. Both protein restrictions and IUGR altered various parameters of oxidative status. In all evaluated structures, protein restrictions resulted in increases in thiobarbituric acid-reactive substances level and index of lipid peroxidation (P<0.001), and in decreases in antioxidant enzyme activities (P<0.005). IUGR also increased lipid peroxidation levels in the blood samples (P<0.04) and protein oxidative damage in the cerebellum and cerebral cortex (P<0.005); however, no effects were detected on the spinal cord. The greatest decrease in CAT activity was in the cerebellum of rats fed with SPR diet (P<0.001). This study suggests that not only severe but also middle protein malnutrition have deleterious effects on CNS structures, including the spinal cord. Protein restriction has a greater effect on the redox state of the CNS than IUGR.
Clinical Neurology and Neurosurgery | 2006
Ümit Özkan; Mustafa Ozates; Serdar Kemaloğlu; Aslan Guzel
We report the case of a 20-year-old man with a gunshot injury as an example of spontaneous migration of a metallic foreign body within the brain. Computed tomography (CT) showed the bullet in the left temporoparietal region. At 10 days follow-up, CT revealed that the bullet had migrated posteriorly, due to the effect of gravity, lodging in the occipital lobe. Although there are a few literature reports of spontaneous migration of a bullet within the brain, this case was unique as the patient was fully conscious without any neurological deficit.
Acta Neurochirurgica | 2015
Ali İhsan Ökten; Yurdal Gezercan; Kerem Mazhar Özsoy; Tuncay Ates; Guner Menekse; Ali Aslan; Eralp Çetinalp; Aslan Guzel
BackgroundTwo different techniques of short-segment instrumentation, with and without a pedicle screw at the fracture level, were compared in thoracolumbar burst fractures in neurologically intact (ASIA-E) patients. The sagittal index, kyphosis angle (Cobb), canal compromise ratio, and compression ratio of the anterior vertebral height were analyzed.MethodsSeventy patients who underwent short-segment stabilization for thoracolumbar (T11-L2) burst fractures in our clinic between 2008 and 2012 were included in this retrospective study. In 35 patients (group 1), a pedicle screw was placed only one level down and one level up from the fracture level. In another 35 patients (group 2), a screw was placed at the fracture level in addition to the short segment. Only neurologically intact patients with burst fractures according to the Denis classification were included. The patients were evaluated according to their age/gender, trauma etiology, and fracture level. Their preoperative and most recent postoperative follow-up radiographs and CTs were evaluated in terms of the sagittal index, kyphosis angle (Cobb), ratio of canal compromise, and anterior vertebral height.ResultsThe two groups were similar in their ages, follow-up periods, and severity of the deformity and fracture. When the pedicle screw was placed at the fracture level in addition to short-segment stabilization, statistically significant improvements in the sagittal index (p < 0.001), local kyphosis (Cobb) angle (p = 0.006), and compression ratio of the anterior vertebral height (p = 0.002) were observed. Concerning the ratio of canal compromise according to the CT findings (p = 0.189), moderate differences were found.ConclusionsShort-segment stabilization in thoracolumbar burst fractures with additional screws at the level of the fracture results in an improved kyphosis correction, sagittal index, and compression ratio of the anterior vertebral height. However, long-term follow-up is needed to determine the clinical significance of these findings.
Pediatric Neurosurgery | 2007
Aslan Guzel; Mehmet Tatli; Uygur Er; Murad Bavbek
A 3-month-old girl was admitted to the hospital with a 2.5 ! 3 ! 2 cm, posterior parietal vertex midline cystic lesion. The smooth lesion was a round pulsating swelling. Neurological examination was within normal limits according to the patient’s age. Her delivery had been via the spontaneous vaginal route with no accompanying anomalies. There was no family history of congenital central nervous system lesions. Magnetic resonance imaging (MRI) was performed, which demonstrated a posterior parietal extra-axial lesion on sagittal T 1 -weighted images. The lesion was isointense similar to cerebrospinal fluid (CSF) on T 1 -weighted sequences ( fig. 1 ). At surgery, a smooth mass was found filled with CSF, which contained no neural or glial tissue within the lesion. No associated venous structure or any other visible venous abnormality was detected. The lesion was excised totally at the dural junction, dura and overlying skin were repaired. A postoperative MRI showed no abnormality except normal postoperative changes ( fig. 2 ). The patient had an uneventful recovery and was discharged without any complication.
American Journal of Medical Genetics Part A | 2007
Aslan Guzel; Mehmet Tatli; Kaya Bilguvar; Michael L. DiLuna; Betul Bakkaloglu; Ali K. Ozturk; Fatih Bayrakli; Murat Gunel
We report on an apparently new syndrome in a consanguineous family with seven members, three of whom have cerebral anomalies including pachygyria and arachnoid cysts along with mental retardation and seizures. The two patients with seizure disorders also had multiple enlarged perivascular spaces seen in the white matter of the centrum semiovale. Our data provide a contribution to the accumulating knowledge on familial cerebral anomalies including arachnoid cysts and lissencephaly. Given the lack of mutation in known lissencephaly genes such as LIS1, 14‐3‐3ε, and DCX, this syndrome may constitute a new phenotype with autosomal recessive inheritance.
Spine | 2008
Senem Senturk; Aslan Guzel; Ebru Guzel
Study Design. Case report. Objective. To report an adult female patient with idiopathic spinal cord herniation presenting with pain without symptoms of myelopathy. Summary of Background Data. Idiopathic spinal cord herniation is a rare but increasingly recognized cause of myelopathy that can be successfully diagnosed with the almost pathognomonic findings on magnetic resonance imaging. There are over 90 cases that were treated surgically reported in the literature. Methods. A 38-year-old woman presented with a 6-month history of chest pain radiating through to the back in bilateral T4 dermatome. Her neurologic examination was normal. Magnetic resonance study revealing ventral displacement and adherence of spinal cord at T4 level led to the diagnosis of idiopathic spinal cord herniation. Mild spinal cord atrophy with the dilatation of dorsal subarachnoid space was determined. Results. The patient is observed-up on conservative treatment for pain. Conclusion. Idiopathic spinal cord herniation is 1 of the causes of unexplained atypical thoracic pain with or without signs and symptoms of myelopathy. Magnetic resonance imaging is recommended to establish the diagnosis in patients, particularly age ranged from 36 to 59, whose clinical and laboratory findings are inconclusive.
Acta Neurochirurgica | 2012
Fatih Bayrakli; Ali İhsan Ökten; Ugur Kartal; Guner Menekse; Aslan Guzel; İbrahim Öztoprak; Ergun Pinarbasi; Hamit Zafer Kars
BackgroundArachnoid cysts are congenital fluid-filled compartments within the cerebrospinal fluid cisterns and cerebral fissures. They most commonly occur sporadically, and familial occurrence has rarely been reported. In this study, we showed the first genetic linkage in the literature in a pure intracranial arachnoid cyst family with autosomal recessive trait.MethodsWe identified an intracranial arachnoid cyst family in southern Turkey whose six of seven offspring had intracranial arachnoid cysts in different localizations, and collected venous blood from seven offspring of the family. Whole-genome linkage analysis was performed in all offspring.ResultsA theorical maximum logarithm of the odds score of 4.6 was identified at chromosome 6q22.31-23.2. This result shows strong genetic linkage to this locus.ConclusionsWe present the first genetic linkage analysis result in a pure intracranial arachnoid cyst family in literature. Further investigation of this linkage area can reveal a causative gene causing the intracranial arachnoid cyst phenotype and can illuminate the pathogenesis of this disease.
Pediatric Neurology | 2014
Ahmet Okay Caglayan; Jacob F. Baranoski; Fesih Aktar; Wengi Han; Beyhan Tüysüz; Aslan Guzel; Bulent Guclu; Hande Kaymakçalan; Berrin Aktekin; Gozde Tugce Akgumus; Phillip B. Murray; Emine Z. Erson-Omay; Caner Caglar; Mehmet Bakırcıoğlu; Yildirim Bayezit Sakalar; Ebru Guzel; Nihat Demir; Oğuz Tuncer; Senem Senturk; Barış Ekici; Frank J. Minja; Nenad Sestan; Katsuhito Yasuno; Kaya Bilguvar; Hüseyin Çaksen; Murat Gunel
BACKGROUND Knobloch syndrome is a rare, autosomal recessive, developmental disorder characterized by stereotyped ocular abnormalities with or without occipital skull deformities (encephalocele, bone defects, and cutis aplasia). Although there is clear heterogeneity in clinical presentation, central nervous system malformations, aside from the characteristic encephalocele, have not typically been considered a component of the disease phenotype. METHODS Four patients originally presented for genetic evaluation of symptomatic structural brain malformations. Whole-genome genotyping, whole-exome sequencing, and confirmatory Sanger sequencing were performed. Using immunohistochemical analysis, we investigated the protein expression pattern of COL18A1 in the mid-fetal and adult human cerebral cortex and then analyzed the spatial and temporal changes in the expression pattern of COL18A1 during human cortical development using the Human Brain Transcriptome database. RESULTS We identified two novel homozygous deleterious frame-shift mutations in the COL18A1 gene. On further investigation of these patients and their families, we found that many exhibited certain characteristics of Knobloch syndrome, including pronounced ocular defects. Our data strongly support an important role for COL18A1 in brain development, and this report contributes to an enhanced characterization of the brain malformations that can result from deficiencies of collagen XVIII. CONCLUSIONS This case series highlights the diagnostic power and clinical utility of whole-exome sequencing technology-allowing clinicians and physician scientists to better understand the pathophysiology and presentations of rare diseases. We suggest that patients who are clinically diagnosed with Knobloch syndrome and/or found to have COL18A1 mutations via genetic screening should be investigated for potential structural brain abnormalities even in the absence of an encephalocele.