Evaluation of tenoxicam on prevention of arachnoiditis in rat laminectomy model.

Post laminectomy arachnoiditis has been shown by experiments with rats and post operative radiological imaging in humans. The purpose of this experimental study was to determine the efficacy of tenoxicam in preventing arachnoiditis in rats. Twenty-four Wistar rats were divided into two groups, and L3 laminectomy was performed. In the tenoxicam group, 0.5 mg/kg tenoxicam was applied intraperitoneally. Normal saline was applied intraperitoneally in the control group. Later, the rats were killed at weeks 3 and 6, and the laminectomy sites were evaluated pathologically for arachnoiditis. The results showed that 6 weeks after surgery, the tenoxicam group showed lowest arachnoiditis grades. However, statistically significant difference was not found in arachnoiditis between the control group and the tenoxicam group. Based on these findings it is concluded that application of the tenoxicam after lumbar laminectomy did not effectively reduce arachnoiditis. Performing the most effective surgical technique without damage around tissue in a small surgical wound and having meticulous hemostasis in surgery seem to be the key for preventing arachnoiditis effectively.

Infliximab administration reduces neuronal apoptosis on the optic pathways in a rabbit hydrocephalus model: a preliminary report.

OBJECT: This study was designed to explore the effects of infliximab on the optic pathway in kaolin induced hydrocephalus rabbit model. METHODS: After injection of kaolin to the cisterna magna of 12 New Zealand rabbits for induction of hydrocephalus, animals were divided into 2 groups and received either infliximab or normal saline. The intracranial pressure measurement was performed 2 times; firstly, before kaolin injection and secondly, before decapitation to ensure that the rabbits had hydrocephalus. After 2 weeks, animals were decapitated. RESULTS: Apoptotic cells in the lateral geniculate body, optic radiation, and optic disc were counted with TUNEL method. Apoptotic cell counts of the lateral geniculate body and the optic radiation were showed statistically significant difference between the infliximab group and the control group. CONCLUSIONS: This study suggests that infliximab may have a neuroprotective effect through its anti-apoptotic property on hydrocephalus induced optic pathways injury.

Radiological and histopathological comparison of microporous polysaccharide hemospheres and oxidized regenerated cellulose in the rabbit brain: a study of efficacy and safety.

AIM: Topical hemostatic agents are widely used in brain surgery but they have some disadvantages such as foreign body reaction, being a focus for infection and causing artifacts in radiological examinations. The purpose of this study is to compare the effectiveness and safety of microporous polysaccharide hemospheres (MPH) with a well known agent, oxidized regenerated cellulose (ORC), histopathologically and radiologically. MATERIAL AND METHODS: Standard brain lesions (4x1mm) were created in 24 hemispheres in 12 New-Zealand rabbits. Animals were divided into three groups; control, ORC and MPH. Twenty-four hours later, all rabbits magnetic resonance brain imaging. After imaging, the animals were sacrificed and the brains were removed for histopathological analysis. RESULTS: Histopathological analysis showed no significant difference between the groups. Radiological examination showed no significant difference between the MPH and ORC groups in terms of edema but the edema in control group was significantly prominent than MPH and ORC groups (p < 0.001). CONCLUSION: A new agent (MPH) provides safe and effective hemostasis in the brain in this study. The most important advantage of microporous polysaccharide hemospheres is their rapid clearance from the surgical field and therefore having the potential of causing less imaging artifacts.

Fractionated gamma knife radiosurgery for optic nerve tumors: a technical report.

AIM: The main purpose of this report is to demonstrate the effects of fractionated radiosurgery regimens in the management of optic gliomas MATERIALS and METHODS: Two patients suffering from progressive loss of vision due to optic nerve gliomas were treated with Gamma Knife radiosurgery in three fractions within three consecutive days instead of a single dose regimen. Patients were followed for 42 and 39 months respectively. RESULTS: The treatment modality was well tolerated by the patients with radiological and neurological tumor control after 42 and 39 months of follow up. There were no additional complications. CONCLUSION: Fractionated regimens of Gamma Knife surgery offer a very good alternative for lesions such as optic glioma and optic nevre sheath meningioma.

Neuroprotective effects of infliximab in experimental spinal cord injury.

BACKGROUND: The aim of the study is to assess the effects of infliximab, a TNF-alpha receptor blocker, in a spinal cord clip compression injury model. METHODS: Clip compression injury model was used for producing spinal cord injury on 32 adult, male Wistar rats (Gazi University Animal Research Laboratory, Ankara, Turkey). After exposing the vertebral column between T7 and T10, total laminectomy was performed with the assistance of a high-speed drill and a surgical microscope. The dura was left intact. Spinal cord injury was performed on all rats with application of a 70-g closing force aneurysm clip for 1 minute. The rats were randomly allocated into 4 groups. Control group received no further therapy, whereas the other 3 groups received methylprednisolone (30 mg/kg intraperitoneal), infliximab (5 mg/kg subcutaneous), and a mixture of these 2 agents. All rats were killed 72 hours later, and the level of lipid peroxides in traumatized spinal cord tissue were measured as thiobarbituric acid-reactive material and determined using the method of Mihara and Uchiyama (Determination of malonaldehyde precursor in tissue by thiobarbituric acid test. Anal Biochem 1978;86(1):271-8). RESULTS: Treatment with infliximab and methylprednisolone decreased MDA levels in rats with spinal cord injury with a statistically significant difference. In addition, combined therapy achieved a more profound decrease in tissue MDA levels, which was also statistically significant. CONCLUSIONS: Infliximab is found as effective as methylprednisolone on spinal cord clip compression injury. Moreover, the combination of these 2 agents demonstrated higher efficacy suggesting a synergistic effect between these 2 agents. However, further studies regarding functional and behavioral analyses as well as biochemical markers are required.

Intracerebral tension pneumocephalus complicating endoscopic sinus surgery: case report.

BACKGROUND: Various forms of intracranial air have been described in the literature. AIM: This report aims to present clinical, radiological and intraoperative findings of a rare intracranial air entrapment case after endoscopic sinus surgery.

A comparison of the effectiveness of waxed paper and Gore-Tex on the minimally invasive epidural fibrosis model.

STUDY DESIGN: Experimental animal study. OBJECTIVE: The authors conducted a study to determine the effectiveness of waxed paper in preventing postlaminectomy epidural fibrosis in rats. SUMMARY OF BACKGROUND DATA: Extensive epidural fibrosis after lumbar surgery may be the underlying cause in most cases of failed back surgery syndrome. Various materials have been used to prevent epidural fibrosis, but only moderate success has been shown. METHODS: Laminectomies were performed at the fourth lumbar vertebra (L-4) in 30 rats. Waxed paper or Gore-Tex was applied in a blinded fashion to the operative sites. In the control group, only the L-4 laminectomy was performed. The rats were killed 28 days after surgery. RESULTS: The extent of epidural fibrosis was evaluated by histologic analysis. There was a meaningful statistical difference among the waxed paper group and the Gore-Tex group compared with the control group, but there was no difference when the effectiveness of waxed paper was compared with that of Gore-Tex. CONCLUSIONS: In this experimental model, the waxed paper applied locally effectively reduced epidural fibrosis, completely avoided dural adherence, and induced no side effects.

A comparison of the local effectiveness of mitomycin C, aprotinin, and Adcon-L in experimental peridural fibrosis.

BACKGROUND: Peridural fibrosis and leptomeningeal adhesion formation are among the common causes of FBSS. Various materials have been used to prevent the compressive effect of postoperative PF on neural structures. We investigated and compared the effects of 3 agents--aprotinin, mitomycin C, and Adcon-L--to PF after lumbar laminectomy in rabbits. METHODS: Four groups each including 8 rabbits were formed: Adcon-L, aprotinin, mitomycin C, and control groups. L3 laminectomy was performed on each animal. One of the 3 agents was administered locally to laminectomy areas in each group. All the animals were killed 4 weeks after the surgery. Peridural fibrosis, arachnoidal fibrosis, and dural adhesions were evaluated histologically and graded. The results were compared statistically by using a standard chi2 test. RESULTS: There were significant differences in the PF grades among the experimental groups and the control group (P < .05). When the fibroblast density and the inflammatory cell density were evaluated, the grades of the experimental groups were better compared with the grades of the control group, but the difference was not statistically significant (P > .05). CONCLUSION: Various materials have been used to prevent the compressive effect of postoperative PF on the neural structures. Aprotinin, mitomycin C, and Adcon-L are effective in preventing PF and dural adhesions in postlaminectomy areas. However, mitomycin C and Adcon-L were more effective than aprotinin in preventing peridural scarring.

Neuroprotective Effects of Vigabatrin on Spinal Cord Ischemia-Reperfusion Injury.

OBJECTIVE: Spinal cord ischemia is a serious and catastrophic clinicopathologic condition. Despite studies reported over the last 20 years, alternative and efficient treatment options remain unclear. We examined the neuroprotective effects of vigabatrin on a spinal ischemia-reperfusion model. METHODS: We divided 24 New Zealand rabbits into 4 groups (control, ischemia reperfusion, and low-dose and high-dose vigabatrin). The control group underwent only abdominal surgery, whereas an abdominal aortic cross-clamp model of spinal ischemia was performed in the other groups. Clips were removed after 30 minutes and 50 and 150 mg/kg vigabatrin was administered intraperitoneally to the low-dose and high-dose groups, respectively. Neurologic examination was performed for 48 hours, after which the rabbits were sacrificed and a blood sample obtained. Biochemical examination of malondialdehyde, advanced oxidation protein products, total nitric oxide, and glutathione levels and superoxide dismutase activities in plasma and tissue sample, and histopathologic examination of the spinal cord were performed and statistical results compared between the groups. RESULTS: Low-dose vigabatrin had statistically significant effects of neuroprotection on spinal ischemia. Although high-dose vigabatrin had similar effects, the results were not statistically significant for all parameters of biochemical analysis. In addition, histopathologic examination showed some toxic effects of high-dose vigabatrin. CONCLUSIONS: Neuroprotective effects of vigabatrin are shown. For clinical use, further studies are needed.

Transcranial arrow injury: a case report.

As demonstrated in various studies, with mortality and morbidity rates reaching 90%-100%, penetrating brain injuries are among the most devastating subjects of neurosurgery. Shell and sharapnell fragments are the most common cause of this type injuries; although rarely reported in "modern times", transcranial arrow injuries may also be the cause. In this report, a 37 year-old male patient, who was shot by an "arrow" accidentally, was evaluated regarding clinical presentation, treatment and clinical progress.

Ischemic stroke complicated by a brain abscess: a case report and review of the literature.

Ischemic stroke and brain abscess are life threatening, severe medical conditions requiring urgent and comprehensive evaluation. Brain abscess is a very rare and dangerous complication of ischemic stroke that can be treated successfully when diagnosed. Association of these two life threatening condition may cause catastrophic results. In this report, we present our experience with an ischemic stroke case complicated by a brain abscess under the light of previous literature. A 64-year-old patient with a cerebral infarction complicated by a cerebral abscess is reported with its clinical and radiological features. Because of their insidious and opportunistic nature, brain abscess complicating cerebral infarcts are pathologies requiring a high index of suspicion for proper treatment and favorable results.

Effect of Iloprost on endothelin-1-induced free radical activation in rabbit brain stem.

Iloprost, a stable analogue of prostacyclin, was used to reverse the early period of vasoconstriction provoked by Endothelin-1 by administering into the rabbit basilar artery. We observed if this produced an effect on the central nervous system parenchyma mediated by free radical system. The red neurons were counted in brain stem sections stained with haematoxylin and eosin, while superoxide dismutase and malondialdehyde levels were measured in brain stem tissue samples as a marker of reactive oxygen metabolites; both 30 and 90 min after administration of either Endothelin-1 (0.25 ng) alone or Endothelin-1 followed by Iloprost (0.5 microg/kg) into the basilar artery. Endothelin-1 significantly increased the number of red neurons, while Iloprost significantly reduced them after 30 and 90 min. However, regarding the reactive oxygen metabolites; a similar reversing effect of Iloprost was not observed although superoxide dismutase levels were significantly decreased after Endothelin-1 infusion.

Topical mitomycin C-induced inhibition of postlaminectomy peridural fibrosis in rabbits.

OBJECT: The authors conducted a study to determine the effectiveness of mitomycin C in preventing postlaminectomy peridural fibrosis in rabbits. METHODS: Laminectomies were performed at L-4 in 12 rabbits. Color-coded cotton pads soaked either with 0.02% mitomycin C or saline were applied in a blinded fashion to the operative sites, with saline-treated laminectomy sites serving as controls. The rabbits were killed 30 days after surgery. The extent of peridural fibrosis was evaluated by histological analysis. The mitomycin C-treated sites showed significantly decreased peridural fibrosis. CONCLUSIONS: Peridural fibrosis can be a devastating condition that develops after laminectomy. Topical application of mitomycin C may be a successful method of preventing postlaminectomy peridural fibrosis.

Intravenous and local intraarterial tissue-plasminogen activator in a rabbit model of acute thromboembolic stroke: angiographic comparison.

The aim of early thrombolytic therapy in acute stroke is to obtain early recanalization of occluded cerebral arteries and prevent or reduce irreversible ischemic brain damage. In this study, Seldinger technique and digital subtraction angiography were used to verify thromboembolic occlusion of the common carotid artery by an autologous 12-hour-old thrombus in 28 rabbits. Thirty minutes after embolization, 2 mg/kg of recombinant tissue-plasminogen activator (rt-PA) was delivered intravenously by way of the femoral vein in group A (n = 8) and through a local intraarterial infusion in group B (n = 8). Twelve control animals received an equivalent volume of saline intravenously (group C, n = 6) or by local intra-arterial infusion (group D, n = 6). A comparison of posttreatment angiographs of the treatment groups and the control groups was used to demonstrate reperfusion induced by thrombolytic therapy. None of the control animals showed any evidence of recanalization. Both intravenously (group A) and intra-arterially (group B) treated animals achieved 100% recanalization, although the average time to recanalization was significantly longer in group A (P = .01; 123.7 vs 82.5 min). These results suggest that local intra-arterial administration of rt-PA within 30 minutes produces more rapid reperfusion compared with the intravenous route. Further studies and additional treatments are needed to widen the therapeutic window and decrease hemorrhagic side effects.

Management of brain metastases from non-small cell lung cancer.

PURPOSE: The purpose of the following study is to evaluate the treatment modalities, clinical status and prognostic factors affecting survival rates in patients with newly diagnosed brain metastasis from non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: NSCLC patients with a new diagnosis of one to four brain metastasis evaluated retrospectively for the effects of treatment regimens on local failure-relapse-free survival (LRFS) and overall survival (OS). The relationship between age, gender, performance status, recursive partitioning analysis (RPA) classification, the primary tumor under control, number of metastatic tumors in the brain and total volume of brain metastasis and prognosis is analyzed. RESULTS: Out of a total of 138 (121 male and 17 female) patients, nearly 44.2% received only gamma-knife (GK); 24.6% were received both GK and whole brain radiotherapy (WBRT), 2.9% had GK and surgery, 3.6% received GK, surgery and WBRT, 10.9% had surgery and WBRT and 12.3% received only WBRT for treatment. Median LRFS of surgery plus WBRT group was significantly higher when compared with WBRT group (P<0.0001). The OS was significantly longer for surgery plus WBRT group than the other treatment groups (P=0.037). When median survival of WBRT-only group compared with surgery plus WBRT, it was significantly higher (29.6 months vs. 16.7 months, P=0.006). Median OS of surgery plus WBRT group was significantly higher than GK plus WBRT group (29.6 months vs. 9.3 months, P=0.007). CONCLUSION: WBRT is still the most effective treatment method following surgery in selected patients according to their age, performance status and spread of the primary disease with NSCLC had limited number brain metastasis. Adding WBRT treatment after surgery significantly improved OS and LRFS.

Effects of phenytoin sodium on dura mater healing in a rat model of CSF leakage.

AIM: Cerebro-spinal fluid (CSF) leakage caused by defects on the dura mater after trauma or some neurosurgical interventions is an important issue. In this study, we investigated the effects of local and systemic use of phenytoin sodium on dural healing. MATERIAL AND METHODS: Thirty-six male Wistar rats were divided into control, local phenytoin and systemic phenytoin groups with 12 rats in each. For each group, a dura defect was created at thoracic segment. Subjects were sacrificed at following 1st and 6th weeks and damaged segments were isolated. The results were compared histopathologically by Hematoxylin-Eosin and Masson-Trichrome staining. Criteria for the rate of collagen, neovascularization, and granulation formation were assessed semi quantitatively according to the histological assessment scale modified by Ozisik et al. RESULTS: Better healing was achieved in the systemic and local phenytoin groups than in the control group. The level of healing was significantly higher in the systemic group in both early and late periods than in other groups (p < 0.01). The level of healing in the late-local group was also statistically significantly higher than that in the control group. CONCLUSION: We observed that both systemic and local uses of phenytoin sodium (especially systemic) have positive effects on dura healing.

Two meningiomas with different histological grades in the same patient. Case report.

A 56-year-old female presented with two intracranial meningiomas with different grades manifesting as speech disorder for one week. Neurological and radiological evaluations showed two distinct tumors suggestive of multicentric meningiomas. Surgical resection of both masses was performed in the same procedure. Histological examination found both meningothelial and atypical meningiomas. Concurrency of meningiomas with different grades in same patient is extremely rare. The present case emphasizes the need for follow up of all patients with meningioma even if the neuroimaging features indicate benign character.

Neuroprotective effects of infliximab in experimental spinal cord ischemic injury.

Reactive oxygen species (ROS) have been implicated in the pathogenesis of spinal cord injury after both ischemia-reperfusion (I/R) and trauma. This experimental study was designed to investigate the potential effects of infliximab, an anti-tumor necrosis factor-α agent, on I/R injury of the rabbit spinal cord. Eighteen New Zealand white rabbits were divided into three groups, each consisting of six rabbits: sham (no I/R), I/R, and infliximab (I/R + infliximab). Spinal cord ischemia was induced by applying an infrarenal aortic cross clamp for 30 minutes. At 48 hours after ischemia, animals were functionally evaluated using the Tarlov score. Changes in the spinal cord were observed by measuring tissue levels of malondialdehyde (MDA), glutathione (GSH), advanced oxidation protein products (AOPP), and superoxide dismutase (SOD) and by evaluating hematoxylin-eosin-stained sections. At 48 hours after ischemia, the Tarlov scores in the infliximab group were higher than those of the I/R group, MDA and AOPP levels in the I/R group were significantly higher than those in the sham and infliximab groups (p < 0.05), and SOD levels in the infliximab group were significantly higher than those in the I/R and sham groups (p < 0.05). The sham group had higher GSH levels than the infliximab group; however, the difference was not statistically significant (p > 0.05). Histological examination revealed that the infliximab group had significantly less vascular proliferation, edema, and neuron loss than the I/R group. These results indicate that infliximab may protect the spinal cord against injury in a rabbit I/R model.

Intracranial meningiomas of childhood and adolescence.

Meningiomas are rare intracranial neoplasms in childhood and adolescence, representing 0.4-4.1% of the pediatric-age tumors and 1.5-1.8% of all intracranial meningiomas. The goal of this study was to determine epidemiology, clinical and radiological features, and long-term outcome of childhood and adolescence meningiomas. Patients operated for intracranial meningiomas of childhood and adolescence between 1983 and 2003 at Gazi University School of Medicine, Department of Neurosurgery, were evaluated retrospectively. This study presents 11 cases (6 male, 5 female), ranging in age from 14 months to 17 years. Age and sex distribution, presenting symptoms, neurological examination results, location of meningiomas, radiological and histopathological findings, and prognosis were reviewed. The results were compared with those reported in the existing literature. Atypical and malignant meningiomas seem to be more common in childhood and adolescence with respect to adult meningiomas. Tumor location, completeness of tumor removal, and pathological grade are the most important prognostic factors.