Electrophysiological, functional and histopathological assessments of high dose melatonin on regeneration after blunt sciatic nerve injury.

The aim of this study was to determine the curative effects of high-dose (100 mg/kg) melatonin on peripheral nerve injury. Forty male Wistar albino rats were randomized into four groups as sham, vehicle, melatonin, and ischemia and their right sciatic nerves were exposed. The process was terminated in the sham group. In the other groups, nerve injury was induced by clip compression. The vehicle group was intraperitoneally administered ethanol 0.1 cc (melatonin solvent), while the melatonin group was intraperitoneally administered a single dose of melatonin (100 mg/kg). Following the surgery, sciatic nerve functional index (SFI) was measured using walking track analysis on days 7, 14, and 21, and latency, amplitude, and muscle action potentials (MAP) field values were measured using electroneuromyography (ENMG) on day 21. Histopathologically, edema, axonal degeneration, myelin damage, and inflammatory response were evaluated in all groups. SFI values were noted to be statistically significantly different among the vehicle, melatonin, and ischemia groups, and the melatonin group showed a faster recovery. In the ENMG evaluations, higher amplitude and field values in the melatonin group indicated that melatonin accelerated peripheral nerve recovery. Histopathologically, although fibers with loss of myelin were identified in the melatonin group, the myelin sheath was preserved in general and the axonal structure was noted to be normal. A single injection of high-dose melatonin was found to preserve myelin sheath, prevent axonal loss, and accelerate functional recovery during the nerve regeneration in peripheral nerve injury.

A giant frontoethmoid mucocele with intracranial extension.

Mucoceles are mucus-containing cysts lined by epithelium. Although benign, they may show expansive growth and remain undiagnosed until symptoms due to compression of surrounding structures arise. We report a rare case of frontoethmoid mucocele with intracranial extension in an 80-year-old woman with complaints of headache, right diplopia and proptosis. A right frontoorbital craniotomy was performed, and a mucocele in the frontal sinus extending into the frontal lobe and orbit was totally removed. The patient was successfully treated without any complication. The two-year follow-up results were satisfactory. Magnetic resonance imaging excluded any recurrence of the mucocele. Combined intranasal and transcranial approach is necessary to treat giant frontoetmoid mucoceles with intracranial extension.

May "Dubel" be a solution for pullout problem of the pedicle screws at osteoporotic spine?

AIM: To improve the strength of stabilization systems currently used in osteoporotic spinal fractures, essentially by increasing the fixation force of pedicle screws. MATERIAL AND METHODS: Six human cadaveric vertebrae were used. Bone mineral densities of the specimens were measured with Dual Energy X-ray Absorptiometry in order to assess the osteoporosis. All vertebrae were found to be severely osteoporotic. Standard pedicle screws were applied to left pedicles of vertebrae. Pedicle screws reinforced by fixing plugs "Dubel" were applied to right pedicles of vertebrae. Afterwards the vertebrae were embedded in acrylic casts to prevent possible fracture of the osteoporotic vertebrae and to obtain a correct vertical pull-out vector. The biomechanical pullout tests were performed with biomechanical testing machine. Pullout forces in each group were recorded and compared with Mann-Whitney U test. RESULTS: The pedicle screws strengthened by "Dubel" were found to be four times stronger than the standard pedicle screws, in the osteoporotic human cadaveric vertebrae. CONCLUSION: "Dubel"-augmented pedicle screws may contribute to developing better stabilization systems for osteoporotic thoracolumbar fractures needing surgery and in the revision of the previous fusion surgeries of the spine.

Ossifying fibroma of the lumbar spine: case report.

Ossifying fibroma of the vertebra is a very rare condition. We report a 16-year-old boy with ossifying fibroma of the third lumbar vertebra. Neurological and laboratory examinations demonstrated normal findings. Low-back pain, in the absence of radicular pain, was the presenting symptom. Plain radiography and computerized tomography scanning revealed an osteolytic lesion. The tumor in the third lumbar vertebra was curetted and filled with bone allograft. The histopathological diagnosis was consistent with ossifying fibroma. There was no postoperative complication. The case is the second to be reported. The clinical and radiological aspects of this rare tumor are discussed with the pertinent literature.

Effects of clotrimazole on experimental spinal cord ischemia/reperfusion injury in rats.

OBJECTIVE: The effect of clotrimazole was examined using a spinal cord ischemia/reperfusion model. METHODS: Twenty albino Wistar rats weighing 234 +/- 12.3 g were used in this study. Rats were anesthetized intraperitoneally with 50 mg/kg ketamine HCl. All animals underwent laparotomy under aseptic conditions. Abdominal aortas of the animals in all but the sham group were exposed. After opening the retroperitoneum, the infrarenal abdominal aorta was clipped for 45 minutes to produce ischemia/reperfusion injury. Polyethylene glycol (PEG, 1 mL) was administrated to the vehicle group. PEG (1 mL) and clotrimazole (30 mg/kg) were administered intraperitoneally in the clotrimazole group. Total laminectomy of T8-T12 was performed on all rats under a microscope. Spinal cords were excised for a length of 2-cm rostrally and 1-cm caudally to the injury site and deep frozen at -76 degrees C for biochemical studies. The levels of malondialdehyde, glutathione-peroxidase, superoxide dismutase, and catalase were measured as an indicator of ischemia level. The most cranial part of the specimens was evaluated morphologically. RESULTS: Treatment with clotrimazole significantly decreased malondialdehyde, glutathione-peroxidase, superoxide dismutase, and catalase levels in comparison with other groups (P = 0.008). Morphologic evaluation revealed that clotrimazole protected the axons and their myelin sheaths from ischemic damage. CONCLUSION: This study showed the neuroprotective effects of clotrimazole on spinal cord ischemia/reperfusion injury.

Massive congenital intracranial immature teratoma of the lateral ventricle with retro-orbital extension: a case report and review of the literature.

Germ cell tumors comprise 0.4-3.1% of all intracranial tumors, and teratoma constitutes 9-30% of them. Congenital intracranial tumors are very rare and only account for 0.5-1.5% of all childhood brain tumors. The most common type of these tumors present at birth is teratomas, which represent 0.5% of all intracranial tumors. Most teratomas are midline tumors located predominantly in the sellar and pineal regions. In this study, we report a neonatal intracranial immature teratoma at the lateral ventricle because of its rare location. A 5-day-old female neonate presented with a history of irritability and left eye protrusion since birth. A head computed tomographic (CT) scan and magnetic resonance imaging (MRI) disclosed a large tumor filling the left lateral ventricle and extending into the ipsilateral retro-orbital space. With left frontotemporoparietal craniotomy, a large grayish-white lobulated vascular mass was encountered, and total removal of tumor was performed. Histological examination revealed the diagnosis of immature teratoma. The prognosis of congenital intracranial immature teratoma is usually poor because the lesions are extensive when they are identified. Prenatal ultrasonography is necessary for the prenatal diagnosis. Fetal MRI should be made for the evaluation of intracranial tumor. If the tumor is detected before the 24th week of gestation, termination of the pregnancy should be considered.

Effects of clotrimazole on experimental spinal cord injury.

BACKGROUND: We examined a possible neuroprotective effect of clotrimazole on spinal cord clip compression injury. METHODS: Rivlin and Tator's acute extradural clip compression injury (CCI) model was used for producing SCI on 24 albino Wistar rats weighing 180-250 g. All rats were anesthetized with 30 mg/kg ketamine HCl intraperitoneally and were breathing spontaneously without tracheal intubation. Total laminectomy of T8-T12 was performed on all rats under operation microscope, and CCI was performed on all rats (expect those in group 1) with a 50-g closing force aneurysm clip for 1 min. Three hours later, all of the rats were killed with sodium pentobarbital. Spinal cords were excised for a length of 2 cm; 1 cm rostrally and caudally to the injury site and deep frozen at -76 degrees C for biochemical studies. RESULTS: Treatment with clotrimazole decreased MDA levels in rats with SCI with a statistically significant difference. CONCLUSIONS: To our knowledge, this the first study that shows the effects of clotrimazole on spinal cord clip compression injury. Clotrimazole was found to be effective on spinal cord clip compression injury, but further investigations are mandatory.

Effects of citicoline on experimental spinal cord injury.

OBJECTIVE: To investigate the effects of citicoline on experimental spinal cord injury (SCI). BACKGROUND: Citicoline has been successfully used in clinical studies of head injury and cerebral infarction, but there is limited literature regarding its use in experimental SCI. STUDY DESIGN: Twenty adult Wistar rats were divided into four groups: sham, trauma, vehicle, and citicoline-treated. SCI was produced using a weight drop technique. Citicoline 300 mg/kg was given intraperitoneally, 5 minutes after the induction of trauma. The animals were sacrificed and 1 cm long samples of injured spinal cord were obtained at 48 hours post-SCI. Lipid peroxidation was estimated by the thiobarbituric acid test. Neurological examinations were performed using a previously described grading scale. RESULTS: Measures of lipid peroxidation and motor scores of the citicoline-treated group were significantly lower than those in the other injury groups. CONCLUSIONS: Citicoline attenuated lipid peroxidation after SCI and improved the motor scores. Further investigations will be required to determine the long-term effects of this drug on spinal cord injury.

Conservative management of spontaneous posterior fossa subdural hematoma in a neonate.

Symptomatic intracranial hemorrhage in term neonates is uncommon, and is usually secondary to trauma, coagulation disorders and/or hypoxia. Posterior fossa hemorrhage in the neonate is a rare neurosurgical emergency and is usually associated with the same etiological factors. Diagnosis is with computed tomography and magnetic resonance imaging. We present a spontaneous posterior fossa subdural hematoma in a term neonate and discuss conservative management.

Clinical course of spontaneous spinal epidural haematoma mimicking Guillain-Barré syndrome in a child: a case report and literature review.

We describe a 9-year-old female with thoracic epidural haematoma. The clinical course simulated Guillain-Barré syndrome (GBS) so intravenous immunoglobulin therapy was started at the paediatric clinic. Magnetic resonance imaging (MRI) 3 days after admission showed thoracic epidural haematoma between T2 and T8. An emergency laminectomy was performed and the patient's neurological symptoms began to improve immediately after surgery and she made a full recovery during the 2 weeks of follow-up. Time is a very important factor in achieving reversibility of symptoms of compressive cord lesions, such as spinal epidural haematoma, and MRI is mandatory for patients with progressive paraplegia, even though the signs and symptoms might suggest GBS.

Intracavernous carotid artery aneurysms.

Six patients with intracavernous carotid artery aneurysms (ICCAAns) were seen at our department from 1998 to 2002. All patients had only one intracranial aneurysm and their ages at diagnosis ranged from 36 to 72 years (median 56). Five were women and four had a history of hypertension. One patient was pregnant. All of the ICCAAns were symptomatic at diagnosis. Duration of symptoms was 2-30 days. On admission to our department, initial symptom was headache in four patients, visual loss in two, eye pain in one, third nerve paresis in two and subarachnoid hemorrhage (SAH) in one. Spontaneous thrombosis was present in two patients. All of the ICCAAns were saccular. Computed tomography (CT) was superior when compared with magnetic resonance imaging (MRI) for diagnosis of ICCAAns on admission. Angiography remains the gold standard for diagnosis and determination of specific anatomical details, which are necessary to plan treatment.

Intratumoral haemorrhage: a clinical study.

Although the incidence of spontaneous intracranial haemorrhage associated with meningioma is 1.3%, the incidence of intratumoral haemorrhage could not be determined. The authors report on 11 patients, six men and five women, with meningiomas that presented as spontaneous intratumoral haemorrhage, among 126 meningioma cases which were evaluated radiologically and histopathologically. The average age of patients was 58.9 years (range 45-72 years). Two (1.5%) cases showed radiological, and nine cases (7.9%) showed microscopic bleeding. Most of these cases also showed microcysts (9.7%) and necrosis (6.3%). The location, histopathological types, sex, age, blood dyscrasia, hypertension do not influence the occurrence of intratumoral haemorrhages in meningiomas. We concluded that microcysts and necrosis are important in the occurrence of intratumoral haemorrhage in meningiomas.

Giant cystic primary cerebral neuroblastoma in a child and solid primary cerebral neuroblastoma in an adult: two case reports.

Primary cerebral neuroblastoma is a rare entity in neurosurgical practice. They occur primarily in young children and are extremely rare in adults. Primary cerebral neuroblastoma is one of a group of highly malignant undifferentiated primitive neuroectodermal tumours arising from germinal matrix cells of the embryonic neural tube. They are difficult to diagnose preoperatively and pathologically. We present two cases of primary cerebral neuroblastoma.

Spontaneous thrombosis of vein of Galen aneurysmal malformation after ventriculoperitoneal shunting.

Aneurysmal dilatation of the vein of Galen (AVG) is a common finding in vascular malformations that involve the Galenic system and spontaneous thrombosis is very rare. Although the presentation of the cases may differ with the age, the mortality and morbidity is high in all age groups. Here, we present a case of AVG in a six-month-old boy. The patient underwent insertion of a ventriculoperitoneal shunt. Surveillance of the lesion with subsequent MRI revealed spontaneous thrombosis of the AVG with excellent clinical outcome. Proposed mechanisms of spontaneous thrombosis include slow flow shunts, obstruction of the venous outflow or obstruction of the feeding artery. The case is discussed with the relevant literature.

The effects of tyrphostine Ag 556 on experimental spinal cord ischemia reperfusion injury.

BACKGROUND: To investigate the effects of Tyrphostin Ag 556 on spinal cord ischemia reperfusion injury. METHODS: The inhibition of tyrosine kinase may represent a novel approach in the treatment of spinal cord ischemia reperfusion injury. Recently, a family of tyrosine kinase inhibitors, the tyrphostins, has been successfully used in models of endotoxemia, peritonitis, and hypovolemic shock. MATERIALS AND METHODS: Twenty-four Wistar rats were used in the study. Rats were divided into 4 groups of 6 animals. The groups were named as sham operated group, injury group, vehicle group, and treatment group. Clamping of the abdominal aorta was performed for 45 minutes with all of the groups except sham-operated group. All of the rats were sacrificed 24 hours after the operation for biochemical and ultrastructural studies. RESULTS: Tyrphostin Ag 556 treatment was found effective on experimental spinal cord ischemia reperfusion injury. The Malondialdehyde (MDA) values of the treatment group were statistically significant lower then the other reperfusion injury groups. The histologic examination showed better cellular structure in the treatment group than the other reperfusion injury groups. The neurologic scores of the treatment group also improved after treatment. CONCLUSIONS: Tyrphostin Ag 556 alters spinal cord ischemia reperfusion injury by inhibiting protein kinases. Further investigations will be required to determine the long-term effects of this drug.

Clear cell meningioma: case report and literature review.

The clear cell meningioma is rare and a recently described histologic variant of meningioma. The most interesting aspect of clear cell meningioma is the high recurrence rate and agressiveness. Until now 17 intracranial clear cell meningioma cases had been reported in the English language literature. We present 2 new cases of clear cell meningioma which is discussed with the relevant literature.

Solitary plasmacytoma with intracranial intraorbital and, paranasal sinus extension.

Intracranial solitary plasmacytomas (ICSPs) are extremely rare tumours in neurosurgical practice, and are often misdiagnosed preoperatively. Here we present a solitary intracranial plasmacytoma with orbital, nasal and paranasal sinus extension. A subtotal excision of the tumour was performed and the complete response was seen after postoperative radio-chemotherapy. The neuroradiological and neurosurgical features of the case are discussed with the pertinent literature.

Posterior epidural migration of lumbar disc fragments: report of three cases.

STUDY DESIGN: Report of three cases. OBJECTIVES: To describe a rare location of intervertebral disc migration. SUMMARY OF BACKGROUND DATA: Migration of sequestered disc fragments to the posterior extradural space is rare, and posterior migration of the free fragments causing cauda equina syndrome is exceptionally rare. METHODS: Three patients with posteriorly migrated epidural disc fragments were evaluated with radiograph, computed tomography, and magnetic resonance imaging and underwent surgery. RESULTS: All of the patients responded well to operative therapy with complete relief of symptoms. CONCLUSIONS: Early surgery should be the first choice of therapy in patients with large posteriorly migrated sequestered disc fragments, to prevent severe neurologic deficits such as cauda equina and conus medullaris syndromes.

Primary parenchymal cerebral cystic haemangiopericytoma: a 5-year follow up of disease progression.

Haemangiopericytoma (HPC) is a rare tumour of the central nervous system. Previously, HPCs were thought to originate from meninges and ventricular walls. Currently, they are accepted as distinctive mesenchymal neoplasms unrelated to meningiomas. Imaging appearances, clinical progression and haemorrhage into a cystic tumour is documented in an 18-year-old man where the final diagnosis, with histopathological verification, proved to be a cystic HPC. This interesting and illustrative case is discussed with the relevant literature.

Acute phase effects of ATP-MgCl2 on experimental spinal cord injury.

The purpose of this study was to study the acute phase effects of adenosine triphosphate (ATP)-MgCl2 on experimental spinal cord clip compression injury. Spinal cord clip compression injury was performed on 36 albino Wistar rats. The rats were divided into five groups. T4-T8 total laminectomy was performed on all rats. Group 1: sham-operated group. Group 2: clip compression group. In group 3, ATP-MgCl2 (100 micro mol/kg) was given 2 min before the "clip compression injury." In group 4, ATP-MgCl2 (100 micro mol/kg) was given 5 min after the clip compression injury. In group 5, ATP MgCl2 (100 micro mol/kg) was administered 8 h after the injury. The spinal cords were excised for a length of 2 cm and deep frozen at -76 degrees C. Tissue malondialdehyde (MDA) levels were used to determine the effects of ATP-MgCl2 on spinal cord lipid peroxidation. In the groups in which ATP MgCl2 was administered after the clip compression injury (groups 4 and 5), the decrease in spinal cord MDA levels was statistically significant when compared with those of the injury group (group 2). Although MDA levels of group 4 were lower than those of group 5, this difference was not statistically significant. Administration of the ATP-MgCl2 before the clip compression injury (in group 3) did not have a statistically significant effect on lipid peroxidation when compared with the injury group (group 2). In this study, we found that ATP-MgCl2 has decreased lipid peroxidation in spinal cord injury and protected the spinal cord from secondary injury after the trauma. We concluded that ATP-MgCl2 may be used in the treatment of spinal cord injuries in conjunction with the other treatment modalities, but further investigations are mandatory.