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Bayram Cirak

Publications and source records attributed to Bayram Cirak.

18 recordsLinked to original sources

The influence of cervical spinal cord stimulation on induced epileptic discharges in rats.

Spinal cord stimulation (SCS), also known as dorsal column stimulation, is a novel technique used widely in pain surgery. However, its effect on other pathologies such as epileptic disorders is unknown. The aim of this study is to evaluate the influence of electrical epidural stimulation of the upper cervical region on epileptic cortical discharges. The long term goal is to elucidate and evaluate a therapeutic central nervous system (CNS) electrical stimulation methodology to treat epilepsy. Twelve Wistar female rats were randomly divided into two groups. In group 1 (six rats under general anesthesia), C2-3 laminectomies were performed and epidural electrodes were placed to perform SCS. To induce epileptic discharges, 1 ml (200 IU) penicillin G was microinjected into the left somatomotor cortex via left stereotactic parietal craniotomies, 0.01 to 0.1 mA at 2 Hz was used to stimulate the spinal cord. In group 2 (the control group, six rats under general anesthesia), C2-3 laminectomies were performed without electrode placement and epileptic discharges were induced with penicillin G microinjections, as described above. Both groups were monitored with digital electroencencephalography (EEG) for 70 min in seven stages and recordings analyzed with power spectral analysis. Spinal cord stimulation decreased penicillin-induced median values of epileptic discharges. Epileptic wave frequencies decreased significantly with increasing intensities of SCS. The results of this study suggest that SCS used for drug resistant epilepsies may be a viable alternative treatment modal.

Animals↗

A retrospective study of central nervous system shunt infections diagnosed in a university hospital during a 4-year period.

BACKGROUND: Ventriculoperitoneal (VP) shunts are used for intracranial pressure management and temporary cerebrospinal fluid (CSF) drainage. Infection of the central nervous system (CNS) is a major cause of morbidity and mortality in patients with CSF shunts. The aim of the present study was to evaluate the clinical features, pathogens, and outcomes of 22 patients with CSF shunt infections collected over 4 years. METHODS: The patients with shunt insertions were evaluated using; age, sex, etiology of hydrocephalus, shunt infection numbers, biochemical and microbiological parameters, prognosis, clinical infection features and clinical outcome. RESULTS: The most common causes of the etiology of hydrocephalus in shunt infected patients were congenital hydrocephalus-myelomeningocele (32%) and meningitis (23%). The commonest causative microorganism identified was Staphylococcus (S.) aureus, followed by Acinetobacter spp., and S. epidermidis. CONCLUSION: In a case of a shunt infection the timely usage of appropriate antibiotics, according to the antimicrobial susceptibility testing, and the removal of the shunt apparatus is essential for successful treatment.

Acinetobacter Infections↗

Does melatonin protect or treat brain damage from traumatic oxidative stress?

A variety of experimental studies have demonstrated the neuroprotective effects of melatonin, based on its antioxidant activity. In a prospective randomized study, the effects of melatonin were investigated in experimental head trauma-induced oxidative stress in rabbits. The experimental study was performed on 30 rabbits. The animals were divided into three groups. Group I (sham procedure): a right parietal craniotomy was performed on each animal, and the dura mater was left intact. Group II: experimental brain trauma (EBT) was performed on each animal using a 1 cm inner diameter x 10 cm long glass tube, through which a 20 g weight (0.5 cm diameter) was dropped onto the brain at the craniotomy site, causing a contusional head trauma. Group III: the same EBT model was performed, but 2.5 mg/kg melatonin was injected intraperitoneally four times (total dose 10 mg/kg); these injections were performed 20 min before the operation, during the trauma, 1 h later and 2 h later. The rabbits were sacrificed after the EBT at 24 h after the brain trauma. The activities of the three principal antioxidant enzymes-catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px)-were determined, and the levels of malondialdehyde (MDA), a product of lipid peroxidation, and glutathione (GSH) were measured in brain homogenates. MDA levels were found to be higher in the EBT group than in the EBT+melatonin group or the sham procedure group. The SOD activity was found to be higher in the EBT group than in the sham procedure group. Enzymatic parameters (except for SOD) were significantly higher in melatonin-treated animals than in EBT animals. GSH levels in melatonin-treated animals were decreased compared with EBT animals. In conclusion, the data indicate that melatonin protects against free radical-mediated oxidative changes in brain tissue by boosting antioxidant enzymes, and in particular lowering lipid peroxidation in rabbits with EBT.

Animals↗

Metastatic germ cell testicular tumor of the eye and brain: case report.

The aim of this report is to contribute to the clinical understanding of this rare combined pathology. Intraocular metastatic tumors are rarely encountered pathologies. Mostly encountered primary sites are breast, prostate, kidney, lung and skin. Testis as a primary site for orbital metastases is rather rare. Metastasis to orbit usually occurs to periorbital structures, but to vitreus is relatively rare. Here we describe a case of intraocular metastatic tumor to the vitreus originating from testicular embryonal cell carcinoma. Patient with intraocular tumor had also intracranial metastasis. He was operated on for intracranial lesion, after an uneventfull postoperative period he was discharged. 2 months later when he died, postmortem examination of the intraocular lesion reported as metastatic embryonal cell carcinoma. As a conclusion testicular embryonal cell carcinoma, eventhough rare, must be considered to metastasize to the eye.

Adult↗

Proton magnetic resonance spectroscopic imaging in pediatric pilomyxoid astrocytoma.

OBJECTS: A pilomyxoid astrocytoma (PmA) is considered to be either a more aggressive variant of a pediatric pilocytic astrocytoma (PA) or a tumor of a separate entity. METHODS: We present two cases of pediatric optic-chiasmatic PmA. Proton magnetic resonance spectroscopic imaging (MRSI) of the PmA revealed decreased concentrations of total choline (Cho), creatine (Cr), and N-acetyl aspartate (NAA). In contrast, proton MR spectra of PAs showed elevated Cho and decreased Cr and NAA signals. CONCLUSION: Low metabolite concentrations in PmAs detected by MRSI may therefore help to distinguish PmAs from PAs preoperatively.

Aspartic Acid↗

The effects of endothelin antagonist BQ-610 on cerebral vascular wall following experimental subarachnoid hemorrhage and cerebral vasospasm.

Endothelin, a potent vasoconstrictor, has been found to increase in the cerebrospinal fluid and serum of patients following subarachnoid hemorrhage (SAH) and to play a major role in the development of cerebral vasospasm. The aim of this study is to investigate the role of endothelin-A antagonist BQ-610 in the experimentally performed cerebral vasospasm following SAH. Thirty New Zealand rabbits were divided into three groups (each n = 10): group A, control group; Group B, SAH group; Group C, treatment (endothelin antagonist BQ-610 treated) group. In the study, the rabbits developed vasospasm after injection of intracisternal autolog blood into the cisterna magna. After cerebral vasospasm development, in group C, endothelin antagonist BQ-610 was injected intracisternally. Morphometrically, basilar artery lumen was constricted 25% and 62% compared to the control group (group A) in the endothelin treated group (group C) and the endothelin untreated group (group B), respectively. Histopathological findings of the basilar artery wall confirmed the therapeutic effect of endothelin antagonist in vasospasm development. Endothelin-A receptor antagonist BQ-610 has a therapeutic effect in the cerebral vasospasm following experimentally performed subarachnoid hemorrhage when used intracisternally.

Animals↗

Intracerebellar granulocytic sarcoma complicating acute myelogenous leukemia: a case report and review of the literature.

Granulocytic sarcoma is a solid mass composed of premature precursors of granulocytic series cells in an extramedullary region. Intraparenchymal central nervous system localization without skull or meningeal invasion is extremely rare. Although different theories have been proposed to explain the mechanism of this unusual disorder, its exact mechanism is still unclear. Some degree of improvement can be achieved after surgery and radiotherapy but its prognosis is poor and most patients die within months. Nine cases of purely intraparenchymal granulocytic sarcomas have been reported in the literature. Here, we report the tenth case and review the current literature.

Cerebellar Neoplasms↗

Spinal injuries in children.

BACKGROUND/PURPOSE: Traumatic spinal injury (TSI) is an uncommon source of morbidity and mortality in children. The aim of this study was to describe childhood TSI in a single level 1 urban pediatric trauma center. METHODS: The authors retrospectively analyzed all children younger than 14 years with TSI, treated at a level I pediatric trauma center between 1991 and 2002 (n = 406, 4% total registry). All children were stratified according to demographics, mechanisms, type and level of injury, radiologic evaluations, associated injuries, and mortality. RESULTS: The mean age was 9.48 +/- 3.81 years. The most common overall mechanism of injury was motor vehicle crash (MVC; 29%) and ranked highest for infants. Falls ranked highest for ages 2 to 9 years. Sports ranked highest in the 10 to 14 year age group. Paravertebral soft tissue injuries were 68%. The most common injury level was the high cervical spine (O-C4). The incidence of spinal cord injury without radiologic abnormality (SCIWORA) was 6%. Traumatic brain injury (37%) was the most common associated injury. Overall mortality rate was 4% in this urban catchment. CONCLUSIONS: TSI in children requires a different preventive and therapeutic logarithm compared with that of adults. The potential devastating nature of TSI warrants that the health care team always maintains a high index of suspicion for injury. Future prospective studies are needed to further elucidate injury patterns.

Accidental Falls↗

Trigeminal neuralgia caused by intracranial epidermoid tumor: report of a case and review of the different therapeutic modalities.

Trigeminal neuralgia (TGN) is characterized by recurrent paroxysms of unilateral facial pain that typically is severe, lancinating, and activated with cutaneous stimulation. Paroxysms typically last for 1 to 2 seconds. Etiology includes compression of the trigeminal nerve by vascular structures, tumors and multiple sclerosis plaques in the medulla spinalis. TGN is rather rare as a presenting symptom with intracranial tumors. Epidermoid tumors comprise 1% of all intracranial tumors. The majority of epidermoid tumors are located at the pontocerebellar angle, the third ventricle, and the suprasellar region. Symptomatology is not different from other tumors located at the same sites. Trigeminal neuralgia may be caused by tumor compressing the nerve itself, an inflammatory response to the epidermoid tumor or vascular compression of the nerve. We describe the case of a 30-year old female presenting with right-sided facial pain. Her past history revealed multiple teeth extractions done to relieve facial pain. Radiological evaluation, including magnetic resonance imaging (MRI), showed a pontocerebellar angle (PCA) epidermoid tumor. TGN resolved completely after total tumor resection. A temporary facial paralysis consequent to surgical removal of the tumor improved 6 months postoperatively, and she remained painfree, without medications.

Journal Article↗

Lipid peroxidation in cerebral tumors.

BACKGROUND: Serum and tissue concentrations of tumor markers or some metabolites are considered to be helpful in diagnosis and follow-up of the central nervous system (CNS) disease. However, markers currently available are not sufficiently sensitive and specific to be used as actual diagnostic tools. Differentiation between the malignant and benign lesions of the CNS is very important, both for determining the optimum therapeutic approach and to predict morbidity and mortality of the disease. Accurate diagnosis of a malignant disease is mostly performed through a surgical resection and histopathologic evaluation. Free oxygen radicals (FOR) are thought to take part in oncogenesis and cellular differentiation. We explored whether FORs can be used as diagnostic tumor markers. METHODS: We investigated the concentration of malondialdehyde (MDA) in the serum and tumor tissue of patients with glial tumor. We have studied 30 patients with malign glial tumor (grades III and IV astrocytoma), 30 patients with low grade glial tumor, 28 healthy individuals, and 10 patients with nontumorous lesions (lobectomy for epilepsy). RESULTS: Patients with CNS tumors showed higher serum MDA concentration compared to control groups (epilepsy patients and healthy subjects). These patients had a higher tumor tissue MDA concentration compared to lobectomy tissue from epilepsy patients. Serum and tissue MDA concentrations were also higher in the malignant glial tumor group compared to the low grade glial tumor group. CONCLUSIONS: Although not specific, tissue and serum concentrations of FORs can be used as a marker to detect the presence and grade of CNS tumors. Further studies are needed to determine the optimum cutoff value for use of serum and tissue MDA concentrations in brain tumors.

Adolescent↗

Optic nerve glioma.

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Combined Modality Therapy↗

MR imaging characteristics of pilomyxoid astrocytomas.

BACKGROUND AND PURPOSE: Pilomyxoid astrocytoma (PMA) is a recently described tumor that typically occurs in the chiasmatic-hypothalamic region in young children and has unique histopathologic and clinical characteristics. These tumors have been previously diagnosed as pilocytic astrocytoma (PA). PMA appears to have a higher rate of recurrence and CSF dissemination than typical PA. METHODS: We analyzed MR findings in four patients with PMA and compared them with those of typical chiasmatic-hypothalamic PA. RESULTS: MR findings of PMA were chiasmatic or hypothalamic enhancing solid tumor with hydrocephalus, highly homogeneous T2 signal intensity that extended into the deep white and gray matter, and CSF dissemination. CONCLUSION: Larger series are needed before the MR imaging findings of chiasmatic or hypothalamic enhancing solid tumor with hydrocephalus, highly homogeneous T2 signal intensity extending into the deep white and gray matter, and CSF dissemination can be used in the differential diagnosis of such tumors.

Astrocytoma↗

Cervical osteochondroma as a cause of spinal cord compression in a patient with hereditary multiple exostoses: Computed tomography and magnetic resonance imaging findings.

Spinal cord compression is a rare but extremely serious complication of hereditary multiple exostoses (HME). Imaging of the spine is important for surgical planning and follow up. We present CT and MR findings in a male patient with HME who developed spinal cord compression from a cervical osteochondroma. Complete recovery was achieved following surgery.

Cervical Vertebrae↗

Central nervous system lipomas.

The lipomas of the central nervous system are rare lesions of congenital origin and are located in the medial line and especially in corpus callosum. Intramedullary spinal lipomas can be seen in the life span of 30 years of age and most frequently coincide with initial puberty period. Magnetic resonance imaging and computerized tomography together with clinical trials are of crucial importance for diagnosis. The first case: A two-year-aged girl who had lipoma in quadrigeminal cistern and who suffered from encephalocraniocutaneous lipomatosis has been clinically studied. The fascial lipoma of the patient has been excised subtotally by the Plastic Surgeons; then the patient has underwent supracerebellar infratentorial operation where the intracranial lipoma has been excised by our team. The histopathology has been reported to be consisting of peripheric nerve tissue and calcification. The second case: A twenty-year-aged man with intramedullary lipoma localized between T1-T4 has been given our clinical trials. T1-T5 total laminectomy and subtotal excision were made for this patient. Due to the fact that the lipomas of central nervous system are rarely seen and are involved in nervous and calcific tissues except for fatty tissues they can be mistaken for hamartomatous masses. The total excision of the lipomas of central nervous system and especially the spinal intramedullary lipomas are quite difficult to be excised since they are tightly entangled with the neural tissue. So any attempt for total excision would be dangerous. Operation for decompression and biopsy is of primary concern.

Adult↗

Is external ventricular drainage useful in primary intraventricular hemorrhages?

Nontraumatic primary intraventricular hemorrhage (PIVH) is characterized by direct bleeding into the neuroventricular system. A very rare condition, PIVH accounts for 3% of all spontaneous intracerebral hemorrhages. Hypertension is a major cause of PIVH. Reports about PIVH in the literature are infrequent and it appears to be a relatively benign condition. Between 1998 and 2001, 15 patients with PIVH were evaluated in the Departments of Neurosurgery of Yüzüncü Yil and Pamukkale Universities; their prognosis and results of treatment with external ventricular drainage (EVD) were recorded. The diagnosis was established easily and rapidly with computed tomography. Prognoses of the patients were made by the Glasgow Coma Score (GCS). Hypertension was the most common etiology (n = 9, 60%); the prognosis for survivors (73.3%) was good (mortality, 26.6%). Elderly patients, who scored low on the GCS, and patients with coagulopathy had poor prognoses. All patients with PIVH underwent surgery with EVD within 24 hours of their hospital admission. Applying EVD had positive results and influenced the prognosis and early and late complications of PIVH accordingly.

Adult↗

Left hemisphere and male sex dominance of cerebral hemiatrophy (Dyke-Davidoff-Masson Syndrome).

Although radiological findings of cerebral hemiatrophy (Dyke-Davidoff-Masson Syndrome) are well known, there is no systematic study about the gender and the affected side in this syndrome. Brain images in 26 patients (mean aged 11) with cerebral hemiatrophy were retrospectively reviewed. Nineteen patients (73.5%) were male and seven patients (26.5%) were female. Left hemisphere involvement was seen in 18 patients (69.2%) and right hemisphere involvement was seen in eight patients (30.8%). We conclude that male gender and left side involvement are frequent in cerebral hemiatrophy disease.

Adolescent↗