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World Neurosurgery | 2013

Toward Changing of the Pathophysiologic Basis of Acute Hydrocephalus After Subarachnoid Hemorrhage: A Preliminary Experimental Study

Ayhan Kanat; Osman Turkmenoglu; Mehmet Dumlu Aydin; Coskun Yolas; Nazan Aydin; Nesrin Gürsan; Levent Tumkaya; Recep Demir

BACKGROUND Acute hydrocephalus (ventricular enlargement within 72 hours) is a common complication in patients with aneurysmal subarachnoid hemorrhage (SAH). Cerebrospinal fluid (CSF) secretion may be increased in the early phases of SAH, but it has not been proved definitively. We studied the histologic features of choroid plexus (CP) in the early and late phases of SAH. METHODS This study was conducted on 20 rabbits, with 5 rabbits in the control group, 5 rabbits in the sham group, and 10 rabbits in the SAH group. In the SAH group, five of the animals were decapitated after 2 days of cisternal blood injections, and the other five animals were decapitated after 14 days of injections. The CP of lateral ventricles were obtained from coronary sections of brains at the level of the temporal horns of the lateral ventricles. Sections were stained with hematoxylin and eosin and Masson trichrome for SAH-related damage and examined stereologically to discern water-filled vesicles, which were counted. Sections were compared statistically. RESULTS The mean numbers of water vesicles were different after SAH between the early decapitated group (group III) and the late decapitated group (group IV). The mean numbers of water vesicles were 2.80 (± 0.05) in the control group (group I), 2.76 (± 0.02) in the sham group (group II), 14.68 (± 0.06) in the early decapitated group (group III), and 4.78 (± 0.13) in the late decapitated group (group IV). Total number of fluid-filled vesicles of CP was also assessed stereologically; the total numbers were 840 (± 16) in group I, 828 (± 7) in group II, 4404 (± 19) in group III, and 1434 (± 41) in group IV. The numbers of water-filled cisterns were significantly increased in the early phases of SAH (P < 0.05). CONCLUSIONS In SAH with aneurysm rupture, increased CSF secretion seems to be triggered by hemorrhage in the early phase, but it is not possible in the late phase because of CP degeneration. In the early phase of hemorrhage, CSF secretion may be stimulated by the irritant receptor glossopharyngeal and vagal nerve endings, which innervate the healthy CP epithelium and arteries. Our findings may be accepted as being causative. It is likewise possible that CSF blockage per se leads to hydrocephalus, and the morphologic changes are sequelae that occur later in the course of disease. This is the first study to show the water vesicles of CP as a causative factor in the development of acute hydrocephalus after SAH.


World Neurosurgery | 2011

Surgical Results of Large and Giant Pituitary Adenomas with Special Consideration of Ophthalmologic Outcomes

Ahmet Murat Müslüman; Tufan Cansever; Adem Yilmaz; Ayhan Kanat; Ersin Oba; Halit Çavuşoğlu; Deniz Şirinoğlu; Yunus Aydin

OBJECTIVE To analyze functioning and nonfunctioning pituitary adenomas (PAs)>3 cm, with special emphasis on preoperative and postoperative visual functions. METHODS The cases consisted of 49 women and 54 men with mean age of 43.2 years (range 19-66 years). All cases had a macroadenoma >3 cm in diameter. The transsphenoidal approach was performed in 117 procedures, and the transcranial approach was performed in 8 procedures. Radical tumor excision was achieved in 50 of 103 patients. Postoperative evaluation was done in 88 patients. Preoperative and postoperative visual acuity, visual field, and ocular fundi and their relationship with the pattern and duration of the symptoms and the size of the tumor were evaluated. RESULTS Normalization of visual acuity was obtained in 71.5% of patients, improvement occurred in 13.6%, symptoms persisted in 13.6%, and symptoms worsened in 1%. Postoperative improvement of visual field defects (VFDs) was observed in 74.1% of patients, and visual impairment score improved postoperatively in 92% of patients. Patients operated on <6 months before the onset of vision loss had better and more sustained visual improvement. One patient died, and 15.5% of patients experienced surgery-related complications. CONCLUSIONS This study shows that patients with severe visual impairment may have remarkable improvement if surgical decompression is done early. The transsphenoidal approach should be performed to correct the patients visual impairment and to relieve the pressure on the optic apparatus caused by macroadenoma of any size.


Experimental Neurology | 2011

The role of ischemic neurodegeneration of the nodose ganglia on cardiac arrest after subarachnoid hemorrhage: an experimental study.

Mehmet Dumlu Aydin; Ayhan Kanat; Adem Yilmaz; Murteza Cakir; Mucahit Emet; Zeynep Cakir; Sahin Aslan; Sare Altas; Cemal Gundogdu

BACKGROUND The heart is innervated by several systems that contribute to the control of the hearts rhythm. The cardiac fibers of the vagus nerve have an important role in the regulation of heart rhythm under many emotional and physical conditions. Severe electrocardiographic disturbances have been reported following subarachnoid hemorrhage (SAH), but ischemic neuronal degeneration of the nodose ganglion of the vagus nerve has not been previously investigated. We examined if there is a relationship between ischemic injury of the nodose ganglion of the vagus nerve and the severity of heart rhythm disorders after subarachnoid hemorrhage. METHODS This study was conducted on 20 rabbits. Four rabbits were used as a baseline group. Experimental subarachnoid hemorrhage was applied to half of the remaining animals (n = 8) by injecting homologous blood into the cisterna magna, and the others (SHAM group, n = 8) were injected with isotonic saline solution in the same manner. For 20 days after the injection, heart rhythm changes were observed daily. After the experiment, normal and ischemic neuron densities in the nodose ganglia of the vagus nerves were examined stereologically. The number of heart rhythm irregularities and the number of degenerated neurons in the nodose ganglia were compared statistically. RESULTS The normal heart rhythm rate was 280 ± 45/min. At the beginning of the SAH, the average heart rate was 220 ± 30/min; about 10 hours later, it decreased to 189 ± 30/min, indicating severe bradycardia. However, after 7 days, the average heart rate had increased to 350 ± 30/min. Six animals died due to irregularities in cardiac function and respiration. Histopathological examinations showed that the average density of normal neurons in the nodose ganglion was 10,500 ± 2500 in the baseline animals and the SHAM group, but the normal neuron density was 8250 ± 1500 in survivors and 6450 ± 1330 in dead animals. The ischemic neuronal degeneration in the nodose ganglia was more severe in the dead animals than in the survivors (p < 0.0001). CONCLUSION Afferent vagus nerves originating from the nodose ganglia have an important role in regulating heart rhythm via their afferent fibers and efferent connections. If neurons of the nodose ganglia are lesioned due to ischemic insult during subarachnoid hemorrhage, heart rhythm regulation by vagus afferent reflexes is disturbed. Vagus pathway paralysis may result in indirect sympathetic overactivity. The development of tachycardia causes depletion of the hearts reserves, and cardiac arrest may be inevitable following extensive subarachnoid hemorrhage.


World Neurosurgery | 2016

Transorbital Ultrasonographic Measurement of Optic Nerve Sheath Diameter for Intracranial Midline Shift in Patients with Head Trauma

Hizir Kazdal; Ayhan Kanat; Hüseyin Fındık; Ahmet Sen; Bulent Ozdemir; Osman Ersegun Batcik; Ozcan Yavasi; Mehmet Fatih İnecikli

OBJECTIVE Measurement of the optic nerve sheath diameter (ONSD) by using sonography is a straightforward, noninvasive technique to detect an increased intracranial pressure, which can even be conducted at the bedside. However, the correlation between ONSD and intracranial midline shift has not been studied. METHODS The authors performed a prospective, blinded observational study in an intensive care unit. Forty-five patients were divided into groups. Of those, 19 patients had a midline shift, whereas 26 had no intracranial pathology or shift and served as control individuals. RESULTS Spearman rank correlation coefficient of difference of ONSD and midline shift was 0.761 (P < 0.0005), demonstrating a significant positive correlation between patients with midline shift and control group. CONCLUSIONS Despite small numbers and selection bias, this study suggests that bedside ultrasound may be useful in the diagnosis of midline intracranial shift by measurement of ONSD.


Asian journal of neurosurgery | 2017

First report of important causal relationship between the Adamkiewicz artery vasospasm and dorsal root ganglion cell degeneration in spinal subarachnoid hemorrhage: An experimental study using a rabbit model

Osman Turkmenoglu; Ayhan Kanat; Coskun Yolas; Mehmet Dumlu Aydin; Naci Ezirmik; Cemal Gundogdu

Background: The blood supply of the lower spinal cord is heavily dependent on the artery of Adamkiewicz. The goal of this study was to elucidate the effects of lumbar subarachnoid hemorrhage (SAH) on the lumbar 4 dorsal root ganglion (L4DRG) cells secondary to Adamkiewicz artery (AKA) vasospasm. Materials and Methods: This study was conducted on 20 rabbits, which were randomly divided into three groups: Spinal SAH (n = 8), serum saline (SS) (SS; n = 6) and control (n = 6) groups. Experimental spinal SAH was performed. After 20 days, volume values of AKA and neuron density of L4DRG were analyzed. Results: The mean alive neuron density of the L4DRG was 15420 ± 1240/mm3 and degenerated neuron density was 1045 ± 260/mm3 in the control group. Whereas, the density of living and degenerated neurons density were 12930 ± 1060/mm3 and 1365 ± 480/mm3 in serum saline (SS), 9845 ± 1028/mm3 and 4560 ± 1340/mm3 in the SAH group. The mean volume of imaginary AKAs was estimated as 1,250 ± 0,310 mm3 in the control group and 1,030 ± 0,240 mm3 in the SF group and 0,910 ± 0,170 mm3 in SAH group. Volume reduction of the AKAs and neuron density L4DRG were significantly different between the SAH and other two groups (P < 0.05). Conclusion: Decreased volume of the lumen of the artery of Adamkiewicz was observed in animals with SAH compared with controls. Increased degeneration the L4 dorsal root ganglion in animals with SAH was also noted. Our findings will aid in the planning of future experimental studies and determining the clinical relevance on such studies.


World Neurosurgery | 2016

Unraveling of the Effect of Nodose Ganglion Degeneration on the Coronary Artery Vasospasm After Subarachnoid Hemorrhage: An Experimental Study.

Coskun Yolas; Ayhan Kanat; Mehmet Dumlu Aydin; Ender Altaş; Ilyas Ferit Kanat; Hizir Kazdal; Aslihan Duman; Betul Gundogdu; Nesrin Gürsan

BACKGROUND Cardiac arrest is a major life-threatening complication of subarachnoid hemorrhage (SAH). Although medullary cardiocirculatuar center injury and central sympathetic overactivity have been suspected of initiating coronary artery spasm-induced cardiac arrest, we aimed to elucidate the effects of vagal ischemia at the brainstem on coronary vasospasm and sudden death in SAH. METHODS Twenty-six rabbits were randomly divided into 3 groups. Control (n = 5); SHAM (n = 8), and SAH group (n = 13). Experimental SAH was applied by injecting homologous blood into the cisterna magna, and the SHAM group was injected with isotonic saline solution also in the cisterna magna., Twenty-one days after the injection, histopathologic changes of the neuron density of nodose ganglia, the vasospasm index values of the coronary arteries, and the electrocardiographic events were analyzed. RESULTS Increased vasospasm index of the coronary arteries and degenerated neuron density of nodose ganglion were significantly different between animals with SAH, control, and SHAM groups (P < 0.005). If neurons of the nodose ganglia are lesioned due to ischemic insult during SAH, the heart rhythm regulation by vagus afferent reflexes is disturbed. CONCLUSIONS We found that there is causal relationship between nodose ganglion degeneration and coronary vasospasm. Our finding could be the reason that many cardiac events occur in patients with SAH. Vagal pathway paralysis induced by indirect sympathetic overactivity may trigger coronary vasospasm and heart rhythm disturbances. Our findings will aid in the planning of future experimental studies and in determining the clinical relevance of such studies.


Turkish Neurosurgery | 2011

The effect of choroidal artery vasospasm on choroid plexus injury in subarachnoid hemorrhage: experimental study.

Adem Yilmaz; Aydin; Ayhan Kanat; Musluman Am; Altas S; Aydin Y; Muhammet Calik; Nesrin Gürsan

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.


Journal of Craniovertebral Junction and Spine | 2014

Describing a new syndrome in L5-S1 disc herniation: Sexual and sphincter dysfunction without pain and muscle weakness

Nezih Akca; Bulent Ozdemir; Ayhan Kanat; Osman Ersagun Batcik; Ugur Yazar; Orhan Ünal Zorba

Context: Little seems to be known about the sexual dysfunction (SD) in lumbar intervertebral disc herniation. Aims: Investigation of sexual and sphincter dysfunction in patient with lumbar disc hernitions. Settings and Design: A retrospective analysis. Materials and Methods: Sexual and sphincter dysfunction in patients admitted with lumbar disc herniations between September 2012-March 2014. Statistical Analysis Used: Statistical analysis was performed using the Predictive Analytics SoftWare (PASW) Statistics 18.0 for Windows (Statistical Package for the Social Sciences, SPSS Inc., Chicago, Illinois). The statistical significance was set at P < 0.05. The Wilcoxon signed ranks test was used to evaluate the difference between patients. Results: Four patients with sexual and sphincter dysfunction were found, including two women and two men, aged between 20 and 52 years. All of them admitted without low back pain. In addition, on neurological examination, reflex and motor deficit were not found. However, almost all patients had perianal sensory deficit and sexual and sphincter dysfunction. Magnetic resonance imaging (MRI) of three patients displayed a large extruded disc fragment at L5-S1 level on the left side. In fourth patient, there were not prominent disc herniations. There was not statistically significant difference between pre-operative and post-operative sexual function, anal-urethral sphincter function, and perianal sensation score. A syndrome in L5-S1 disc herniation with sexual and sphincter dysfunction without pain and muscle weakness was noted. We think that it is crucial for neurosurgeons to early realise that paralysis of the sphincter and sexual dysfunction are possible in patients with lumbar L5-S1 disc disease. Conclusion: A syndrome with perianal sensory deficit, paralysis of the sphincter, and sexual dysfunction may occur in patients with lumbar L5-S1 disc disease. The improvement of perianal sensory deficit after surgery was counteracted by a trend toward disturbed sexual function. Further researches are needed to explore the extent of this problem.


Autonomic Neuroscience: Basic and Clinical | 2011

Role of neuron density of the stellate ganglion on regulation of the basilar artery volume in subarachnoid hemorrhage: An experimental study

Selim Kayaci; Ayhan Kanat; Mehmet Dumlu Aydin; Ahmet Murat Müslüman; Mete Eseoglu; Mustafa Karalar; Cemal Gundogdu

BACKGROUND The role of neuron density (of the stellate ganglion) in basilar artery vasospasm after subarachnoid hemorrhage (SAH) has not previously been investigated. This subject was studied. METHODS This study was conducted on 24 rabbits. Four of them were used as the baseline control group. Experimental SAH was applied to the 15 animals; the remaining five of them were used as a sham group injecting by the serum physiologic saline (PS) and followed up twenty days later. Stellate ganglion neuron densities were estimated stereologically. Vasospasm index (VSI) was used to assess the severity of vasospasm. The value of VSI between 1 and 1.5 was accepted as no vasospasm, 1.5-2 was accepted as light vasospasm and 2 or greater than 2 was accepted as severe vasospasm. Results were compared statistically. RESULTS The mean basilar artery VSI in the control group (n: 4) was calculated as 1.24±0.39 and the neuron density of stellate ganglion was calculated as 8320±675/mm(3). These values in the PS group (n: 5) were calculated as 1.26±0.37 and 8380±680/mm(3). In animals with light basilar artery vasospasm (n: 6), the basilar artery VSI and neuron density of stellate ganglion were 1.65±0.37, 9210±460/mm(3) consecutively, but the basilar artery VSI was 2.07±0.40 and neuron density was 12,075±950/mm(3) in animals with severe vasospasm (n: 9). CONCLUSION The neuron density of stellate ganglion may play an important role in the development of basilar artery vasospasm. The beneficial effect of sympathectomy for the prevention of cerebral vasospasm may be explained through this mechanism.


Journal of the Neurological Sciences | 2014

Important casual association of carotid body and glossopharyngeal nerve and lung following experimental subarachnoid hemorrhage in rabbits. First report

Coskun Yolas; Ayhan Kanat; Mehmet Dumlu Aydin; Osman Turkmenoglu; Cemal Gundogdu

OBJECT The glossopharyngeal nerves (GPNs) and carotid bodies (CBs) have an important role in the continuation of the cerebral autoregulation and cardiorespiratory functions. The relationship between degenerative injury of CB and the GPN in subarachnoid hemorrhage (SAH) was studied. METHODS Twenty rabbits were included in this study. Five of them (n=5) were used as control group. The remaining animals (n=15) were exposed to experimental SAH. In the six animals of the SAH group, severe signs of illness were observed, and these six animals were killed in the first week after SAH. Others animals (n=9) were followed for 20 days and then sacrificed. GPNs and CBs were examined and, the live and degenerated GPN axon number, and of CB neuron numbers were stereologically estimated. RESULTS The mean number of live neurons in CBs was 4206.67±148.35 and live axons of GPNs were 1211.66±14.29 in the animals of the control group. The number of degenerated neurons of CBs was 2065±110.27 and the number of degenerated axons of GPNs was 530.83±43.48 in early killed animals with SAH. The number of degenerated neurons of CBs and the number of degenerated axons of GPNs were found as 1013.89±4184 and 2270.5±134.38 in the living animals with SAH, respectively. CONCLUSIONS High number of degenerated axons of GPN and neurons of CBs of the early killed animals suggest that the mortality in early SAH might be due to GPNs injury secondary to compression of their axons or supplying vessels by the probably herniated brainstem, and secondary denervation injury of CBs, and lung.

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Bulent Ozdemir

Recep Tayyip Erdoğan University

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Hizir Kazdal

Recep Tayyip Erdoğan University

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Ugur Yazar

Karadeniz Technical University

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Adem Yilmaz

University of Texas Southwestern Medical Center

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Mehmet Sabri Balik

Recep Tayyip Erdoğan University

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