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Featured researches published by Tayfun Hakan.


Neuropathology | 2005

Accuracy and diagnostic yield of stereotactic biopsy in the diagnosis of brain masses: Comparison of results of biopsy and resected surgical specimens

Fügen V. Aker; Tayfun Hakan; Selhan Karadereler; Murat Erkan

The aim of this retrospective study was to investigate the diagnostic yield and accuracy of stereotactic biopsy in patients harboring brain mass. Stereotactic biopsy was performed in 130 patients between 1995 and 2000 in an educational and research hospital in Turkey. The results of histological analysis were compared to the resected specimens in 23 patients. The lesions were lobar in 62% of cases and deep‐seated in 38% of cases. During the biopsy procedures, the pathologist was in the operating theatre and a very small fragment was used for cytological examination. No frozen section was used in any of the cases. Samples were diagnostic in 122 cases. The overall diagnostic yield of the procedure was 94%. A definitive histological diagnosis was not made in eight patients. The histological diagnoses of the two procedures were identical (complete agreement) in 16 cases. In three cases, the histological diagnoses between the two procedures were slightly different without impact on patient care (minor disagreement). The diagnosis of the stereotactic biopsy was completely changed after craniotomy in four cases (major disagreement). The accuracy of the histological diagnosis was 83%. There was only one major complication, which involved intracerebral hemorrhage. Despite the limited number of patients who underwent resection, our data suggest that stereotactic biopsy of brain masses is a safe and accurate technique that can obtain adequate tissue for histological diagnosis, thus providing the best avaible treatment for patients. Cytological evaluation of the streotactic biopsy also is a highly effective tool for obtaining sufficient material during the procedure in many cases.


Free Radical Research | 2009

The protective effect of alpha lipoic acid against traumatic brain injury in rats.

Hale Z. Toklu; Tayfun Hakan; Necat Biber; Seyhun Solakoglu; Ayliz Velioğlu Öğünç; Goksel Sener

Traumatic brain injury (TBI) was induced by a weight-drop device using 300 g–1 m weight-height impact. The study groups were: control, alpha-lipoic acid (LA) (100 mg/kg, po), TBI, and TBI + LA (100 mg/kg, po). Forty-eight hours after the injury, neurological scores were measured and brain samples were taken for histological examination or determination of thiobarbituric acid reactive substances (TBARS) and glutathione (GSH) levels, myeloperoxidase (MPO) and Na+-K+ ATPase activities, whereas cytokines (TNF-α, IL-1β) were determined in blood. Brain oedema was evaluated by wet–dry weight method and blood–brain barrier (BBB) permeability was evaluated by Evans Blue (EB) extravasation. As a result, neurological scores mildly increased in trauma groups. Moreover, TBI caused a significant decrease in brain GSH and Na+-K+ ATPase activity, which was accompanied with significant increases in TBARS level, MPO activity and plasma proinflammatory cytokines. LA treatment reversed all these biochemical indices as well as histopathological alterations. TBI also caused a significant increase in brain water content and EB extravasation which were partially reversed by LA treatment. These findings suggest that LA exerts neuroprotection by preserving BBB permeability and by reducing brain oedema probably by its anti-inflammatory and antioxidant properties in the TBI model.


Journal of Neuro-oncology | 2005

Cerebellar liponeurocytoma/lipidized medulloblastoma.

Fugen Vardar Aker; Selvinaz Özkara; Pinar Eren; Önder Peker; Serdar Armağan; Tayfun Hakan

Cerebellar liponeurocytoma that has been recently identified as a distinct entity by the World Health Organization is characterized by areas of lipomatous differentiation and apparently by a favorable prognosis. In this paper, we described a case of 49-year-old female showing progressive clinical course inspite of a low labeling/mitotic index. We also review the relevant literature. Although, basically all reported cases share a similar histological pattern, i.e. focal accumulations of adiposities in an otherwise typical small cell tumor like central neurocytoma, some clinical properties such as (age, proliferative potential, therapy and survival) are not uniform. The exact biological behavior of this special variant tumor is established. Yet, this needs further confirmation on a large number of cases with longer follow-up periods.


Brain Injury | 2009

Cysteinyl-leukotriene receptor antagonist montelukast decreases blood–brain barrier permeability but does not prevent oedema formation in traumatic brain injury

Necat Biber; Hale Z. Toklu; Seyhun Solakoglu; Mıne Gultomruk; Tayfun Hakan; Zafer Berkman; F. Gul Dulger

Introduction: Traumatic brain injury is highly associated with the over-production of reactive oxygen species. The aim of this study was to investigate the putative neuroprotective effect of montelukast, a cysteinyl-leukotriene receptor antagonist, in a rat model of traumatic brain injury (TBI). Methods: Sprague Dawley rats were subjected to TBI with a weight-drop device using 300 g-1 m weight-height impact. The groups were: control (saline), montelukast (10 mg kg −1 per day, ip), trauma and trauma + montelukast. Two days post-trauma, neurological examination scores were measured and animals were decapitated and the brain tissues were taken for the histologic and biochemical [malondialdehyde (MDA)—an index for lipid peroxidation, reduced glutathione (GSH), myeloperoxidase (MPO)—an index for neutrophil infiltration and Na +/K +-ATPase activity] evaluations. Brain oedema and blood–brain barrier (BBB) permeability were also evaluated. Results: The neurological examination scores mildly increased in trauma groups at 48 hours. Although the scores were decreased in the montelukast treated group, they were still significantly higher than the control. The trauma caused a significant increase in brain water content and Evans blue (EB) extravasation. Montelukast treatment reduced BBB permeability. It also decreased lipid peroxidation and MPO activity. Conclusion: The present study suggests that montelukast may have beneficial effects against TBI-induced oxidative stress of the brain.


Journal of Spinal Cord Medicine | 2010

Neuroprotective Effects of Alpha-Lipoic Acid in Experimental Spinal Cord Injury in Rats

Hale Z. Toklu; Tayfun Hakan; Hasan Celik; Necat Biber; Can Erzik; Ayliz Velioğlu Öğünç; Dilek Akakin; Esra Çikler; Sule Cetinel; Mehmet Erşahin; Goksel Sener

Abstract Background: Oxidative stress is a mediator of secondary injury to the spinal cord following trauma. Objective: To investigate the putative neuroprotective effect of α-lipoic acid (LA), a powerful antioxidant, in a rat model of spinal cord injury (SCI). Methods: Wistar albino rats were divided as control, vehicle-treated SCI, and LA-treated SCI groups. To induce SCI, a standard weight-drop method that induced a moderately severe injury (100 g/cm force) at T10 was used. Injured animals were given either 50 mg/kg LA or saline at 30 minutes postinjury by intraperitoneal injection. At 7 days postinjury, neurologic examination was performed, and rats were decapitated. Spinal cord samples were taken for histologic examination or determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and DNA fragmentation. Formation of reactive oxygen species in spinal cord tissue samples was monitored by using a chemiluminescence (CL) technique. Results: SCI caused a significant decrease in spinal cord GSH content, which was accompanied with significant increases in luminol CL and MDA levels, MPO activity, and DNA damage. Furthermore, LA treatment reversed all these biochemical parameters as well as SCI-induced histopathologic alterations. Conversely, impairment of the neurologic function caused by SCI remained unchanged. Conclusion: The present study suggests that LA reduces SCI-induced oxidative stress and exerts neuroprotection by inhibiting lipid peroxidation, glutathione depletion, and DNA fragmentation.


Neurological Research | 2010

Effect of COX-2 inhibitor meloxicam against traumatic brain injury-induced biochemical, histopathological changes and blood–brain barrier permeability

Tayfun Hakan; Hale Z. Toklu; Necat Biber; Huseyin Ozevren; Seyhun Solakoglu; Pelin Demirtürk; Fügen V. Aker

Abstract Objective: The overproduction of reactive oxygen species and resultant damage to cellular proteins or lipids of cell membranes and DNA by free radicals are the underlying mechanisms of many neuropathologies. Cyclooxygenase-2 (COX-2) inhibitors have been suggested to be neuroprotective by reducing prostanoid and free radical synthesis, or by directing arachidonic acid metabolism through alternate pathways. This study investigated the putative neuroprotective effect of the COX-2 inhibitor, meloxicam, in a rat model of diffuse brain injury. Methods: Sprague–Dawley rats were subjected to traumatic brain injury with a weight-drop device using 300 g−1 m weight–height impact. The groups were: control, meloxicam (2 mg/kg, i.p.), trauma and trauma + meloxicam (2 mg/kg, i.p.). Forty-eight hours after the injury, neurological examination scores were measured, the animals were decapitated and brain tissues were taken. Brain edema and blood–brain barrier (BBB) permeability were evaluated by wet–dry weight method and Evans blue (EB) extravasation respectively. In brain tissues, malonedialdehyde, glutathione, myeloperoxidase and Na/K-ATPase levels were measured. Results: The neurological examination scores mildly increased in trauma groups 48 hours after the induction of trauma. Meloxicam treatment improved the altered neurological status. The trauma caused a significant increase in brain water content that was partially reversed by meloxicam. Meloxicam also reduced the EB extravasation indicating the preservation of the BBB integrity. Meloxicam treatment also significantly reduced the increase in malondialdehyde and myeloperoxidase levels and restored glutathione content of the brains that had been significantly increased after trauma. Conclusion: Meloxicam exerts neuroprotective effect by preserving BBB permeability and by reducing brain edema (probably by its anti-inflammatory properties) in the diffuse brain injury model.


International Journal of Neuroscience | 2011

Meloxicam Exerts Neuroprotection on Spinal Cord Trauma in Rats

Tayfun Hakan; Hale Z. Toklu; Necat Biber; Hasan Celik; Can Erzik; Ayliz Velioğlu Öğünç; Şule Çetinel; Göksel Şener

ABSTRACT Traumatic injury to the central nervous system results in the delayed dysfunction and neuronal death. Impaired mitochondrial function, generation of reactive oxygen species (ROS), and lipid peroxidation occur soon after traumatic spinal cord injury (SCI), while the activation of compensatory molecules that neutralize ROS occurs at later time points. The aim of the current study was to investigate the putative neuroprotective effect of the COX2 inhibitor meloxicam in a rat model of SCI. In order to induce SCI, a standard weight-drop method that induced a moderately severe injury (100 g/cm force) at T10, was used. Injured animals were given either 2 mg/kg meloxicam or saline 30 min postinjury by intraperitoneal injection. At seven days postinjury, neurological examination was performed and rats were decapitated. Spinal cord samples were taken for histological examination or determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and DNA fragmentation. Formation of ROS in spinal cord tissue samples was monitored by using a chemiluminescence (CL) technique. SCI caused a significant decrease in spinal cord GSH content, which was accompanied with significant increases in CL, MDA levels, MPO activity, and DNA damage. On the other hand, meloxicam treatment reversed all these biochemical parameters as well as SCI-induced histopathological alterations. Furthermore, impairment of the neurological functions due to SCI was improved by meloxicam treatment. The present study suggests that meloxicam, reduces SCI-induced oxidative stress and exerts neuroprotection by inhibiting lipid peroxidation, GSH depletion, and DNA fragmentation.


Turkish Neurosurgery | 2011

The safety and diagnostic value of frame-based and CT-guided stereotactic brain biopsy technique.

Mehmet Erşahin; Numan Karaaslan; Mehmet Sabri Gürbüz; Tayfun Hakan; Mehmet Zafer Berkman; Osman Ekinci; Nazim Denizli; Fugen Vardar Aker

AIM The aim of our study was to examine the effects of the use of Transcutaneous Electrical Nerve Stimulation (TENS) in patients who had undergone spinal surgery on pain, functionality, depression and consumption of analgesic agents. MATERIAL AND METHODS Fifty-Four patients were randomized and placed into two groups, patient-controlled analgesia (PCA) plus TENS and only PCA. To assess the pain levels of the patients, the Visual Analog Scale (VAS) was used. In the assessment of their functional levels, the Timed Up and Go test (TUG) was utilized and in the assessment of their depression, the Beck Depression Inventory (BDI) was used. The measurements were performed before the operation and on the first and second postoperative days. The side effects were recorded from the analgesic agents. RESULTS During the first and second days after the operation, a decrease in the pain levels was noticed in the TENS group (p 0.05). CONCLUSION TENS was effective in reducing analgesic agent-related side effects and in reducing analgesic consumption. In addition, TENS also decreased activity related pain.Fungal infections of the central nervous system (CNS) are uncommon and occur mainly in immunocompromised patients. We describe a case of central nervous system aspergilloma without any evidence of systemic or paranasal foci in a diabetic but otherwise immunocompetent 71-year-old female treated successfully with surgical resection and medical therapy with voriconazole. Magnetic resonance imaging (MRI) after 6 months of voriconazole showed improvement and no evidence of residual or recurrent disease. Given its good CNS penetration, voriconazole along with surgical resection appears to be promising in treatment of these infections. Our case also demonstrates the importance of surgical intervention in the diagnosis and management of these atypical cases.AIM: Zygapophysial joints have been a well-recognized source of low back pain. This paper compares the efficacy of lumbar zygapophysial joints blockage and medical therapy in terms of pain relief, loss of working days and recurrence of pain in a population with mechanical low back pain. MATERIAL AND METHODS: 80 patients suffering from low back pain were included in the study. Patients were divided into 2 groups. Patients in Group I were given diclofenac sodium, thiocolchicoside and were recommended bed rest. Patients in Group II received zygapophysial joints blockage by prilocaine, bupivacaine and methylprednisolone acetate. Both of the groups were evaluated with a Oswestry low back pain disability questionnaire and visual analog scale for pain. RESULTS: Posttreatment VAS and ODQ scores were significantly lower than pretreatment scores. The decrease in these scores in Group II was greater than those of Group I. CONCLUSION: Blockage of the lumbar facet joints is a rapid and effective way to reduce pain originating from lumbar facet joints.AIM Synovial cysts are relatively common in the lumbar spine and very uncommon in the cervical spine. Several case reports and a few small series have been reported in the literature over the past four decades. There are two distinct cervical spine synovial cyst categories: atlantoaxial and the subaxial cervical spine. The surgical treatments are very different. MATERIAL AND METHODS We report eleven patients undergoing transoral resection and posterior fusion for histologically confirmed symptomatic atlantoaxial synovial cysts. This represents a retrospective review over 18 years. The authors analyzed the literature of patients who underwent surgical treatment for symptomatic atlantoaxial synovial cysts. RESULTS There were four male and seven female patients with a mean age of 76 years (range 54-84 years). All patients presented with cervical myelopathy. Patients were neurologically assessed pre- and postoperatively and outcome reported using the Modified Rankin Outcome score. Mean follow-up period was 22 months (range 6-120 months). Ten of the eleven patients had improvement in their postoperative assessment and one patient remained unchanged. CONCLUSION Myelopathy is the presenting symptom in the vast majority of these patients. Surgical resection and decompression of the neural structures can be an effective treatment for symptomatic atlantoaxial synovial cysts.AIM Surgery is the treatment of choice for children who had tethered cord syndrome (TCS). However, a detailed technique for the release of spinal cord is not described yet. The aims of this study are to present our series of TCS in children and to focus on the details of surgical technique. MATERIAL and METHODS Forty-nine children with tethered cord syndrome underwent surgical treatment for the release of spinal cord between 2004 and 2009. The mean age was 4.6 years (2 days-13 years). Twenty (40.8%) patients were female and 29 (59.2%) were male. Among the 49 children, 41 (83.7%) had different spinal malformations and 8 (16.3%) had no associated lesion. Sectioning of the filum terminale, cutting the arachnoid and fibrous bands, protection of the rootlets and correction of the associated malformations was the standard surgical method to release the spinal cord. RESULTS Neurological improvement was observed in 4 (8.2%) patients, while the neurological status was unchanged in the others. Cerebrospinal fluid fistula was the main complication and was observed in 3 patients. No mortality or neurological deterioration was encountered. CONCLUSION Spinal cord release with appropriate technique seems to be beneficial in maintaining neurological functioning in children with TCS.AIM Postlaminectomy epidural fibrosis is the formation of scar tissue over the dura mater following posterior spinal surgery. This devastating complication is responsible for the substantial amount of failed back syndromes. MATERIAL and METHODS Twenty male Wistar-Albino rats each weighing 350-400 grams were used. Following L3-L5 laminectomy, the rats were randomly divided into 2 groups, with 10 rats in each group. In the control group, only a laminectomy was performed. In the drug group, 5 mg/ml tacrolimus was topically applied with a cotton pad soaked with the drug solution for 5 minutes. The animals were killed on the 30th postoperative day injecting a lethal dose (250 mg/kg) of pentobarbital and the involved dural segments were removed for histopathological and ultrastructural evaluations. RESULTS Epidural scar thickness and the density were significantly lower in the animals treated with tacrolimus than those of the control group. CONCLUSION Promising evidence regarding the anti-scar potential of tacrolimus merits further research to optimize the dosage and the usage of the drug.AIM The aim of this study is to evaluate the changes between the initial and late cranial CT scans in patients with mild-to-moderate head trauma. MATERIAL and METHODS Of the two thousand six hundred and forty-four patients hospitalized for head trauma within a two-year period, 112 (4.24%) patients scored 8 or above in the Glasgow coma scale and there were changes between initial and late head CT. RESULTS Of these, 103 had worsening CT findings. Neurological status deteriorated in 30% of these cases. Forty-six patients required surgery based on findings seen on the delayed scans. Neurological status was stable in 50% of the cases. All the eight patients who expired had abnormal CT scans initially and had progression in their late scans. CONCLUSION In patients with mild-to-moderate head trauma, serial CT scanning may independently modify treatment decisions in a subgroup of patients. Judgment for delayed scans should be made on an individual basis by taking the risk factors into account.AIM: Anterior cervical fusion procedures are among the most commonly performed spinal operations. Investigators have reported pseudoarthrosis rates ranging from 3 to 36% following anterior cervical fusion operations. The diagnosis of pseudoarthrosis has been based on the triad of pain, radiographic evidence of instability, and loss of correction or fixation. Scintigraphic imaging may be involved in pseudoarthrosis investigation by increase of nuclear agent uptake at the operated level but today it is not used in clinical practice as a routine imaging modality. MATERIAL AND METHODS: Nine cases operated for degenerative disc disease on single level but suffering postoperative prolonged neck pain were involved in the study. All cases underwent 99mTc-hydroxymethylene diphosphonate (HMDP) bone SPECT later than postoperative twelfth month. RESULTS: Results showed a correlation between severity of neck pain and fusion status. CONCLUSION: Increased and prolonged uptake of nuclear agent should cause a suspicion on so-called fusion, proven by radiology.Grisels syndrome designates subluxation of atlanto-axial joint unrelated to trauma or bone disease. Atlanto-axial subluxation is seen after the upper neck inflammatory processes of head and neck region. Moreover, this rare clinical entity has been observed after various otolaryngological surgical approaches including adenoidectomy, tonsillectomy and mastoidectomy. An 8-year-old girl and 14 year-old boy presented with complaints of painful torticollis. The first patient was operated on at another health center due to adenoid hypertrophy. She was referred to our clinic on the postoperative 5th day with painful torticollis. The diagnosis was established by computerized tomography and three-dimensional reconstructions. The second patient had a history of throat infection. Radiological investigation demonstrated atlantoaxial subluxation. The patients were treated with external fixation, antibiotic therapy, muscle relaxants, and anti-inflammatory therapy. Early diagnosis and appropriate treatment resulted in a good outcome in our patients. Grisels syndrome must be considered in the differential diagnosis in children with painful torticollis associated with upper respiratory tract infection and after various otolaryngological surgical procedures. We report two cases of Grisels syndrome which emphasize on the importance of early diagnosis for appropriate and successful treatment.AIM: Spinal cord injury (SCI) leads to an inflammatory response that generates substantial secondary damage within the tissue besides the primary damage. Ghrelin, 28 amino-acid peptide, has been shown to modulate the release of proinflammatory cytokines and exert antiinflammatory effects. The aim of the current study was to investigate the anti-inflammatory effects of ghrelin, in a rat model of SCI. MATERIAL AND METHODS: Wistar albino rats were divided as control, SCI, and ghrelin-treated (10 μg/kg/day, ip) SCI groups. In order to induce SCI, a standard weight-drop method that induced a moderately severe injury (100 g/cm force) at T10, was used. Injured animals were given either ghrelin or saline 15 min post-injury. RESULTS: In plasma samples, neuron-specific enolase (NSE) and S-100β protein levels were evaluated. Spinal cord samples were taken for histological examination or determination of myeloperoxidase (MPO) activity and DNA fragmentation. SCI caused significant increases in plasma NSE and S-100β levels and tissue MPO activity and DNA damage. On the other hand, ghrelin treatment improved histological findings as well as biochemical parameters while it failed to improve the impairment of the neurological functions due to SCI. CONCLUSION: The present study suggests that ghrelin could reduce SCI-induced oxidative stress and exert anti-inflammatory effects in the spinal cord following trauma.BACKGROUND Lhermitte-Duclos disease is typified by a hamartomatous lesion of the cerebellum. It is usually seen in females. The usual presentation is of raised intracranial pressure along with cerebellar signs. CASE REPORT We report an 18-year-old female patient who presented to us with history of headache and gait ataxia and was observed to have Lhermitte-Duclos disease with cervical cord syrinx on imaging. DISCUSSION To our knowledge this is the fifth case of Lhermitte-Duclos disease with syringomyelia in the pediatric age group. The treatment of this condition is decompression of the lesion. Malignant transformation never occurs and the prognosis is excellent.AIM: The aim of this study was to determine the relationship between ischemic neurodegeneration, of the petrosal ganglion of the glossopharyngeal nerve, and BP fluctuations, after subarachnoid hemorrhage (SAH). MATERIAL AND METHODS: Twenty-four rabbits had their blood pressure and heart rhythms studied daily over 20 days. Then, the histopathology of the petrosal ganglion was examined in all animals. Normal and apoptotic neuron density of the petrosal ganglion and blood pressure values were compared statistically. RESULTS: Mean total volume of the petrosal ganglia was calculated as 0.9 ± 0.34/mm3. BP level of control group was 96.1 ± 2.1 mmHg; 116.5 ± 4 mmHg of mild hypertension (HT) group and 128.1 ± 3.6mmHg in the severe HT group. When the groups were compared to each other they were significantly different. The level of normal-apoptotic neuron in control group was 11,240 ± 802/mm³ -40 ± 6.3/mm³; 9730 ± 148.7/mm³ - 1560 ± 256.2/mm³ in the mild HT group and 6870 ± 378.8/mm³-4240 ± 628.2/mm³ in the severe HT group. When the groups were compared to each other there was significantly difference. CONCLUSION: Blood pressure variability observed in this study may be explained by ischemic neurodegeneration of petrosal ganglia caused by SAH. The results of this study suggest that petrosal ganglion ischemia has potential implications for the development of hypertension. These findings suggest that new treatment strategies should be considered for the treatment of SAH.AIM Concordance of EEG findings and MRI is best correlated with favored surgical outcome in patients with unilateral mesial temporal sclerosis (MTS). If there is no evidence for unilateral focus with scalp EEG, invasive recordings are undertaken. In this report we describe the investigation process for epilepsy surgery in patients with unilateral MTS and contralateral ictal scalp EEG findings. MATERIAL AND METHODS The data of all adult patients who had undergone videoEEG recording with subdural and/or depth electrodes at our center in almost 7.5 years, were reviewed. Four patients with unilateral MTS and contralateral ictal onset on scalp EEG were included. Their invasive EEG recordings and surgical outcomes were examined. RESULTS Four patients met the inclusion criteria. Invasive recordings demonstrated ictal onset in the mesial temporal lobe ipsilateral to MRI findings. In one patient we have also proven the false lateralization of scalp EEG simultaneously during the recordings with depth electrodes. All operated cases are seizure free during follow-up. CONCLUSION Before the decision of epilepsy surgery we have to identify the semiology and ictal EEG findings in patients with unilateral MTS and concordant IEDs. Bilateral depth recordings must be considered to show the ipsilateral hippocampal epileptogenic focus.AIM To assess the efficacy of the far lateral approach, without drilling of the occipital condyle, in the management of anterior intradural tumors at the craniocervical junction. MATERIAL AND METHODS Ten patients suffering from foramen magnum tumors were operated upon via the far lateral approach without drilling of the occipital condyle. All patients underwent postoperative CT scan of the brain. An MRI and CT of the craniocervical junction were done 3 months postoperatively to assess the extent of tumor and bone removal respectively. RESULTS The far lateral approach was found adequate for complete excision in eight out of ten cases of foramen magnum tumors. In the remaining two cases, the tumors were found adherent to the brain stem so complete excision was not done. CONCLUSION The far lateral approach (without drilling of the occipital condyle) proved adequate for excision of most cases of anteriorly situated foramen magnum tumors.AIM Knowing the distance between the superior and inferior border of Parkinsons triangle and the location of the abducent nerve within the cavernous sinus is important to decrease the complications which may occur during surgery. We aimed to investigate the cavernous sinus to decrease the complications that may occur during surgery to this area. MATERIAL AND METHODS Fifty MRIs without pituitary gland abnormality were chosen for radiological assessment of CS. These images were from 18 males and 32 females, with ages ranging from 9 to 58 years and a median age of 28 years. We evaluated structures within and on the lateral wall of the cavernous sinus (especially Parkinsons triangle) with magnetic resonance imaging. The position of the abducent nerve and its level according to the cranial nerves running close the lateral wall were examined. RESULTS At the level of pituitary stalk, the distance between the trochlear nerve and the ophthalmic nerve ranged from 1 to 4 mm bilaterally. The abducent nerve was located between the trochlear and the ophthalmic nerves in 30% cases bilaterally. CONCLUSION The knowledge of the position of the abducent nerve will provide a great benefit in minimizing the rate of complications that may occur during the resection of tumors of the cavernous sinus.AIM Foramina transversaria (FT) are located on the transverse processes of cervical vertebrae. These foramina are known to exhibit variations with regard to size, shape and may even be absent or duplicated. The aims of this study are to investigate the shape, size and variations of FT in an ancient population and to point out the importance of double FT in the human anatomy. MATERIAL and METHODS 262 ancient skeletons, dated 6th c AD, were unearthed from the Iasos Archaeological site between 1979 and 1987. Of these skeletons, 22 cervical vertebrae belonging to 21 individual skeletons were examined for the variations of FT. RESULTS Fifteen (68.2%) of the skeletons were male and 6 were female. All of the FT were round in shape. Among the 22 cervical vertebrae, double FT was found in 5 (22.7%) vertebrae, while unilateral in 3 and bilateral in 2. Asymmetrical FT was observed only in one (4.5%) vertebra. The mean diameter of FT was 6.2 mm in the right side and 6.4 mm in the left. CONCLUSION Double FT exists since the antiquity. The recognition of this variation provides safety and effectiveness for the posterior approaches of the cervical spine.Basically Chiari type III malformation is a combination of encephalocele with of brain stem and cerebellar abnormality. Although Klippel-Feil syndrome may be associated with other congenital anomalies, this syndrome is mainly associated with varying degrees of cervical vertebral fusion anomalies. In this study, we reported the association of Chiari type III malformation and Klippel-Feil syndrome with the mirror movement by imaging studies. The main involvement in Chiari type III malformation and Klippel-Feil syndrome is in the craniocervical junction. In such a small area, the emergence of these complex pathologies in our case was remarkable. Our patient had reconstruction surgery of the posterior fossa and his encephalocele was excised successfully. Hydrocephaly and/or deterioration in the functions of other posterior fossa structures have not been seen in the patients follow-up.AIM To evaluate the long-term outcomes for the surgical treatment of thoracic and thoracolumbar spinal tuberculosis with anterior radical debridement and reconstruction with titanium mesh cages (TMCs). MATERIAL AND METHODS 69 patients with thoracic and thoracolumbar spinal tuberculosis were retrospectively analyzed. Outcomes data included VAS back pain, subjective clinical results, and radiographic data. RESULTS All patients had resolution of their infections, obtained solid bony fusions without failure of fixation, experienced improvement of neurological function, and improved in their VAS back pain scores at final long-term follow-up. In the thoracic spine group, 92.3% of patients had good or excellent subjective clinical results. The loss of kyphotic angle correction and intervertebral height was 9.6% and 3.8%, respectively. In the thoracolumbar spine group, 93.3% of patients had good or excellent subjective clinical results. The loss of kyphotic angle correction and intervertebral height was 12.8% and 4.2%, respectively. CONCLUSION Anterior radical debridement and reconstruction using TMCs for the treatment of thoracic and thoracolumbar spinal tuberculosis is an acceptable treatment option. Solid bony fusion, good clinical outcomes as well as improvement of neurological function can be achieved although TMCs subsidence can occur.AIM: Chronic subdural hematoma is a frequently encountered entity in neurosurgery in particular in elderly patients. There in a high variance in the treatment in literature. MATERIAL AND METHODS: We report our experience of percutaneous evacuation of chronic subdural hematoma in 28 patients. RESULTS: From January 2007 to July 2009, 28 patients underwent percutaneous evacuation. 27 of the 28 patients (96.4%) became asymptomatic or improved clinically. Six weeks later, the scan showed the hematoma had completely disappeared in 18 of the cases. We did not have any postoperative infection. CONCLUSION: Treatment of chronic subdural hematoma using a percutaneous operative technique is a minimally invasive method with sufficient outcome and a therapeutic alternative to the craniotomy.The fifth lumbar vertebra has massive transverse processes that are continuous with the pedicle and encroach the body of the vertebra. These processes are mainly meant for the attachment of the iliolumbar ligament. With increasing age, the iliolumbar ligament can undergo secondary degenerative changes such as calcification, hyalinization, and myxoid degeneration. The authors present the incidental discovery of extremely elongated transverse processes of the fifth lumbar vertebra in a 45-year-old woman who underwent surgery for an intervertebral disc herniation. We also propose a possible pathogenesis to explain this rare condition and conclude that this unusual variant may be caused by calcification of the iliolumbar ligament rather than a congenital anomaly.AIM To confirm and compare the therapeutic efficacies and adverse effects of Chinese botulinum toxin type A (CBTX-A, Lanzhou Biological Products Institute, China) and current Botox (Allergan Inc., CA, USA) in the treatment of blepharospasm (BS) and hemifacial spasm (HFS). MATERIAL AND METHODS We performed an open, prospective, comparative trial comparing CBTX-A and Botox for the treatment of BS and HFS in 273 patients since 2006. 107 patients were treated with current Botox and 166 with CBTX-A, with the age, disease durations and severity of spasm matched. The patients enrolled were followed up for 6 months. RESULTS There were no significant differences in the clinical effects of the two preparations, including the onset of response, peaked effect time and duration of effects (p > 0.05). The Cohen scores showed a significant reduction after BTX-A injections. Considerable improvement of symptoms for the BS and HFS patients was observed 7 days, 4 weeks, 12 weeks, and 24 weeks after the injection with either current Botox or CBTX-A (p 0.05). No statistical differences were noted in adverse reactions between them (p > 0.05). CONCLUSION The two preparations were both simple and effective for the patients with blepharospasm and hemifacial spasm.Subtentorial subdural empyema is a rare form of intracranial suppuration. We present two cases treated at our department within the last 11 years. The common source was an ear infection. Both patients presented with headache, fever, vomiting and stiff neck. Only one patient had disturbed consciousness. Both patients received aggressive antibiotic therapy. The first patient was treated with suboccipital craniectomy and evacuation of pus collection, while the second patient was treated conservatively with antibiotics and ventriculoperitoneal shunt for his associated supratentorial hydrocephalus. Both blood cultures and empyema collection were sterile. Neuroimaging with computed tomography and magnetic resonance imaging permitted accurate diagnosis and localization of the purulent collections. At follow up of 11 years for the first case and 10 months for the second, both patients had complete neurological recovery except for right mild sixth nerve palsy in the patient with conservative treatment.AIM: Surgical removal of spinal meningiomas is usually not difficult. In neurosurgical practice, their locations and growing patterns may affect surgical results. Ventrally located and en plaque meningiomas may not be removed totally. The aim of this study was to present the results of surgery in cases with spinal meningiomas, and reveal the factors affecting outcome. MATERIAL AND METHODS: There were 46 cases operated between January 1995 and December 2009 in single clinic. There were 33 female and 13 male patients. The mean age was 52. All patients underwent microsurgical resection using posterior approach. RESULTS: Total resection was obtained in 38 patients (82%). Twenty-eight (61%) patients experienced clinical improvement after surgery. The tumor was completely dorsal to the spinal cord in 30 cases, dorsolateral in nine and ventral to the spinal cord in seven cases. We experienced eight recurrences (17%). Recurrences were seen most commonly seen in ventrally located tumors (62%). CONCLUSION: Complete resection of spinal meningiomas seems to produce a good clinical outcome. Recently, advances in microneurosurgery and neuroimaging techniques have resulted in decreases in morbidity and recurrence rates in spinal meningiomas.AIM: Histopathological diagnosis is always necessary to make an effective treatment plan for intracranial mass lesions. This study aimed to evaluate the diagnostic efficacy, and associated mortality and morbidity of CT-guided stereotactic biopsy procedures in a large number of patients with intracranial lesions. MATERIAL AND METHODS: A total of 290 cases undergoing CT-guided stereotactic biopsy for intracranial lesions were included in this retrospective study. Clinical, radiological and histological data in patient records were examined. RESULTS: The mean age of the patients was 46.6 years (range: 2-82 y). Pediatric patients comprised 6.3% (n=13) of the total population. Examination of paraffin embedded histological preparations revealed a tumoral mass in 240 (82.8%), a non-tumoral mass in 37 (12.8%), and non-definable lesions in 13 (4.5%). Therefore, the diagnostic value in this series was 95.5%. Postoperative mortality rate was 0.8% (n=2). When histopathological diagnoses made after biopsy and surgical resection were compared in 42 patients with available data, a complete or partial agreement was present in 90.5%. CONCLUSION: Our findings support that frame based-stereotactic biopsy is a safe and valuable technique that allows the neurosurgeon to obtain tissue samples for histopathological diagnosis of intracranial mass lesions in almost any region.: Intaosseous meningiomas (IM) are the one of the less frequent benign tumors of the skull. The etiology of IM has not been cleared yet. The frontoparietal and orbital regions are the most common locations for IM. The average age for IM diagnosis is 50.5. A 16-year-old girl with a right frontoparietal mass was referred to our outpatient clinic. Cranial CT revealed a mass lesion which resulted in expansion in the right parietal and posterior frontal bone, having lytic and sclerotic regions inside with accompanying irregular cortex in inner and outer tables of the calvarium. Prediagnosis was osteosarcoma according to the imaging studies and after the performed biopsy and consecutive surgery, the lesion was diagnosed as IM. Though CT with bone windows is often useful, it is not always diagnostic. Biopsy plays an important role in calvarial vault lesions for planning the treatment. In our case, malignant criteria in radiology did not match the benign histology revealed. Radiological preoperative misdiagnosis of meningioma is possible.The involvement of spinal column in cyst hydatid disease is rare and hard to treat. The gold standard treatment is total removal of the cysts without rupture. However, recurrence after surgery is almost inevitable and reoperations carries technical difficulties and higher morbidity. We present a 69-year-old woman with two cystic masses at the T12 level, which compress the spinal cord causing severe paresis in her left leg. Under local anestesia, the cysts were aspirated and irrigated with 20% hypertonic saline solution via bilateral T12 transpedicular route. We aimed to report that percutaneous CT guided treatment should be considered as an alternative therapeutic option in case of recurrent spinal cyst hydatid.Calvarial cavernous hemangiomas (CHs) comprise 0.2% of benign neoplasms of the skull and frequently occur in the second and fourth decades. Their occurrence in infancy is extremely rare and they can initially be misdiagnosed as cephal hematoma or caput succadeneum that can occur due to the birth trauma, but trauma is not a predisposing factor. CT scan is more helpful than other neuro-imaging studies and untreated CHs of the skull may show progression. Only two cases of congenital primary CH of the skull without intracranial invasion have been reported in the literature. Herewith we reported a 4-month-old infant operated on due to a CH of the parietal bone and discussed the diagnostic and therapeutic modalities.AIM Cerebral arteriovenous malformations (AVMs) are congenital lesions which rarely recur after complete microsurgical excision. MATERIAL AND METHODS This case report presents a 35-year-old woman who had been referred with a hemorrhagic AVM five years ago. This patient has recently undergone microsurgical excision for her left parieto-occipital Grade II AVM and surgical clipping of the left posterior inferior cerebellar artery (PICA) aneurysm which was concomitantly detected. She is the oldest case reported whose AVM recurred as Grade III, which is bigger than her first AVM associated with an aneurysm. CONCLUSION Although some authors do not propose routine additional follow-up in adults after the initial negative postoperative angiogram, we believe that such patients should be followed clinically and radiologically.AIM Genetic absence epilepsy rats from Strasbourg (GAERS) provide a model of absence epilepsy. Although excessive GABA mediation within the thalamo-cortico-thalamic circuit has been shown to play a role in absence epilepsy, neuronal networks of hippocampus have recently received attention. Glutamic acid decarboxylase (GAD) was previously shown to be increased after convulsive seizures in the mossy fiber terminals (MFTs) of hippocampus. The aim of the present study was to investigate whether the change in the level of this enzyme in convulsive seizures is also observed in rats having genetic absence epilepsy. MATERIAL AND METHODS Hippocampal CA3 and dentate regions were processed for transmission electron microscopic evaluations. Thin sections were incubated with anti-GAD65/67 antibody. The NIH Image Analysis program was used for the quantitative analysis. RESULTS It was observed that GAD65/67 immunoreactivity was positive in CA3 and dentate gyrus MFTs of both groups and the difference in the density of immunolabeling between the groups was not statistically significant. CONCLUSION The present study demonstrated that GABA synthesizing enzyme, GAD, is found in MFTs of Wistar and GAERS hippocampus and this enzyme does not show an increase in these terminals in absence epilepsy, in contrast to convulsive seizures.AIM We examined whether vasospasm of choroidal arteries (ChAs) may be resulted in ischemic injury in choroid plexus (CP) after subarachnoid hemorrhage (SAH). MATERIAL AND METHODS This study has been conducted on 30 rabbits. Eight, fourteen and eight of them were used as control, SAH and SHAM groups, respectively. The volumes of choroidal arteries were examined and measured by using the micrometric microscope barr. Ischemic morphological changes of the choroid plexus cells and villus were examined as follows: cellular shrinkage (1 point), cytoplasmic condensation (2 points), angulation (3 points) and villus desquamation (4 points) were considered as 1st, 2nd, 3rd, 4th degree downward choroid plexus degeneration criteria. Degeneration scores of 1 to 4 criteria were calculated by summing the exacerbated ones with the existing one. RESULTS Choroidal artery diameter&volume, and CP degeneration scores in three groups were evaluated: The mean volumes were 1.080 ± 0.650 mm³, 0.907 ± 0.330 mm³, 0.480 ± 0.175 mm³ and the degeneration scores of choroidal plexuses were scored as 0 and 1- 1, and 4- 3 and 10 in the control, SHAM and SAH groups respectively. A significant correlation between the degree of vasospasm and CP degeneration was found. CONCLUSION Vasospasm of choroidal arteries may be at a serious degree in cases with SAH incurs damages on choroid plexuses, and affects structures which play important roles in immune, endocrine, detoxifying, thermoregulatory, and secretory functions of the brain resulting in worsened prognosis.AIM: Nitrogen Mustard (NM) is an alkylating agent that damages cellular nuclear DNA after penetrating tissue. This results in cytostatic, mutagenic and cytotoxic effects. We used biochemical analyses to investigate the effect of NM gas administered through the dermal and respiratory routes, on the brain cortex of rats and also tried to show whether the antioxidant Proanthocyanidin (PC) could decrease this effect. MATERIAL AND METHODS: A total of 30 rats were randomized into three groups: Group I: Control group, Group II: NM group, and Group III: NM + PC group. The rats were sacrificed 3 days after NM gas exposure. A segment of the cortical tissue was prepared for biochemical analyses. RESULTS: Biochemical analyses of cortical neural tissue regarding the Enzymatic Antioxidant Defense against NM were performed. The results of these analyses implied that PC was effective for healing of cortical neural tissue. CONCLUSION: These findings imply that structural changes induced by mustard gas can be prevented and restored by proanthocyanidin treatment.AIM: There is no clear knowlegde in the literature about two-level vertebral corpectomy using the iliac bone crest for fusion and rigid plate fixation. We present our experience with two-vertebral level cervical corpectomy and reconstruction. MATERIAL AND METHODS: Each patient was graded according to the Nuricks Grade (1972) and the modified Japanese Orthopaedic Association (mJOA) Scale (1991), and the recovery rates were calculated. All patients had two-level vertabral corpectomy. Anterior iliac crest bone graft with titanium plate fixation was applied to all patients. RESULTS: Postoperatively the mJOA score raised up to 15.5. Mean recovery rate was 69%. Average 25.2 degrees correction of kyphosis was achieved in 21 patients. Among the postoperative complications, three cases (12%) had temporary C5 nerve palsy that was resolved in three weeks, two cases had (8 %) graft malposition and infection, and three cases (%12) had temporary donor site pain. CONCLUSION: Excellent fusion rates can be achieved following two-level corpectomy with iliac bone graft repacement. This techique is easy, cost effective and safe. If the bone graft is harvested from the iliac crest by standart approach and between anatomical landmarks, most patients do not experience persistent pain at the donor site.


Turkish Neurosurgery | 2010

Pseudoaneurysm of the superficial temporal artery following revision of a middle cerebral artery aneurysm clipping: case report and review of the literature.

Tayfun Hakan; Mehmet Erşahin; Hakan soMAy; Fugen Vardar Aker

Pseudoaneurysms of the superficial temporal artery are mostly traumatic in origin. Here, a case of a superficial temporal artery aneurysm that emerged following a recraniotomy is presented. A 59-year-old woman was admitted with subarachnoid hemorrhage. She underwent a pterional craniotomy and clipping of a saccular aneurysm of middle cerebral artery bifurcation. A control digital subtraction angiography on the 3rd postoperative day revealed partial filling of the aneurysm and a revision was performed. The second control digital subtraction angiography on the 4th postoperative day of the revision showed a pseudoaneurysm of the left superficial temporal artery. The pseudoaneurysm was excised successfully under local anesthesia. In conclusion, pseudoaneurysm of the superficial temporal artery should be considered among the early postoperative complications of the surgical procedures at the superficial temporal artery territory. Although some conservative approaches are used, excision of the aneurysm is recommended for treatment.


Turkish Neurosurgery | 2010

Diagnostic and therapeutic role of CT-guided stereotactic surgery in the management of intracranial tuberculomas.

Mehmet Erşahin; Tayfun Hakan; Erdoğan Ayan; Zafer Berkman; Osman Ekinci; Nurgul Ceran; Fugen Vardar Aker

AIM CT-guided stereotactic methods have long been used for the diagnosis and treatment of intracranial masses. Intracranial tuberculoma is a rare form of extrapulmonary tuberculosis. Histological confirmation is the gold standard for a correct diagnosis. However, histopathological diagnosis and excision of these lesions have advantages over open surgical methods. This study presents our experience on the use of stereotactic biopsy and excision in the management of intracranial tuberculomas. MATERIAL AND METHODS Thirteen patients with intracranial masses underwent stereotactic procedures for tissue samples to establish histopathological diagnosis. In 6 suitable patients, stereotactic microsurgical excision was performed for both diagnostic and therapeutic purposes, whereas only stereotactic biopsy was conducted in the remaining subjects. RESULTS The tuberculoma diagnosis was established in 12 out of 13 cases (92%). Seizure control was achieved in all patients admitted with a history of seizures. There was no procedure-related mortality, none of the patients suffered permanent disability and most procedures were uneventful. Total resection without any residual mass was done. All patients responded to antituberculous treatment with complete lesion disappearance. CONCLUSION These findings suggest that CT-guided stereotactic surgery of intracranial tuberculomas has advantages over other methods, with a potential to become the first-line modality, particularly as a diagnostic tool, in the management of these lesions.

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Mehmet Erşahin

Istanbul Medeniyet University

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