The effect of the sildenafil citrate on cerebral vasospasm and apoptosis following experimental subarachnoid hemorrhage in rats.

AIM: The therapeutic effect of sildenafil citrate on cerebral vasospasm after experimental subarachnoid hemorrhage (SAH) was studied in a rat model. METHODS: We used four groups of seven rats were as follows: no SAH, no treatment; SAH only; SAH plus 2 days of peroral sildenafil citrate 5mg/kg treatment and SAH plus 2 days of peroral sildenafil citrate 15 mg/kg treatment. Three different parameters were evaluated including the diameter of the basilar artery, the level of lipid peroxidation and the degree of the apoptosis 48 hours following SAH. RESULTS: The results showed that sildenafil citrate attenuated SAH-induced cerebral vasospasm in the treatment groups in terms of the diameter of the basilar artery and lipid peroxidation in the two treatment groups, but there was no difference in terms of the level of apoptosis. CONCLUSION: This study indicates that further research on the therapeutic effect of sildenafil citrate can be combined with the use of any apoptosis-blocking agent for the treatment of cerebral vasospasm following experimental subarachnoid hemorrhage.

Paraparesis following straining accompanied by spontaneous thoracolumbar spinal epidural hematoma: a case report.

Spontaneous spinal epidural hematoma (SSEH) is a rare disease that requires emergency surgical intervention because it can cause serious and permanent neurological damage. Its etiology is related to coagulopathy, vascular malformation, hypertension, neoplasms, infections and idiopathic causes. It is frequently observed in the cervicothoracic and thoracolumbar regions. Inadequate spinal vascularization of the thoracolumbar junction increases the risk of spinal infarcts in lesions in this region. Therefore, prompt and effective surgical intervention is critical in patients with a thoracolumbar SSEH. We conclude that prognosis would be better than it is if patients with complete neurological damage were to undergo spinal decompression within the first 36 hours, and patients with incomplete neurological damage were operated on in the first 48 hours. We report a 71-year-old female patient with a history of aspirin use who developed paraparesis accompanied by SSEH following straining, and emphasize the importance of early surgical treatment.

Atypical presentation of Guillain-Barre syndrome with acute hydrocephalus.

A 32-year-old man was treated with a ventriculo-peritoneal shunt for acute panventricular hydrocephalus. On the third postoperative day, an ascending tetraparesis and subsequent respiratory failure developed. Based on the clinical findings, cerebrospinal fluid study and electrophysiological results, a diagnosis of Guillain-Barre syndrome (GBS) was made. Despite plasmaphoresis and immunoglobulin infusion, the patient was ventilator dependent and bed-bound for 4 months. One year later, he was able to walk without assistance and had only slightly wasting of the intrinsic hand muscles. This is the first report of acute hydrocephalus preceding the symptoms of GBS.

Attenuation of microtubule associated protein-2 degradation after mild head injury by mexiletine and calpain-2 inhibitor.

The objective of the study was to address the early effects of mild, closed, head injuries on neuronal stability and the prevention of microtubule-associated protein-2 (MAP-2) degradation by mexiletine and calpain-2 inhibitor. Twenty-four rats were divided into four groups: control group (1); trauma group without treatment (2); mexiletine-pretreated and subjected to trauma group (3); trauma subjected and then calpain-2 inhibitor received group (4). All animals were subjected to mild, closed, head trauma. Frontal lobes were removed and processed for staining and immunofluorescent labelling of MAP-2 cytoskeletal proteins, which were evaluated by confocal microscopy in serial optical sections showing the three dimensional cytoarchitecture of affected areas. MAP-2 decoration in almost all neurons obtained from traumatized brain regions drastically diminished, while minute filamentous and granular profiles in axons and/or dendrites were retained together implying a massive degradation/depolymerization of microtubules. In contrast, in mexiletine-pretreated animals, MAP-2 positivity in axonal and perikaryonal profiles was fairly retained, which clearly depicts the protective role of mexiletine after trauma. Compared with mexiletine-pretreated group, calpain-2 inhibitor treated group displayed a less well-preserved MAP-2 expression. Mexiletine can prevent cytoskeletal structure and protein degradation after mild head trauma. Calpain-2 inhibitor prevents protein degradation, but cytoskeletal organization is better preserved with mexiletine.

Dissapearance of arachnoid cyst after rupturing into subdural space.

Arachnoid cysts are developmental anomalies usually diagnosed in childhood. The most important complications of arachnoid cysts are subdural haematomas and hygromas and intracystic haemorrhage. In our case we present a 7-year-old boy whose arachnoid cyst ruptured into the subdural space following a mild head injury and disappeared after draining the subdural haematoma by burr-holes.

Fusiform aneurysm of the superior cerebellar artery: short review article.

Fusiform superior cerebellar artery (SCA) aneurysms are quite rare and only 9 cases have been reported in the literature. Fusiform aneurysms are a small group of cerebral aneurysms among the most difficult to treat. The therapeutic approaches in the limited number cited in the literature include surgery and endovascular occlusion. Surgical techniques which have been used are parent artery occlusion, trapping or body clipping of the bleeding site, and wrapping for fusiform aneurysms. Neurological condition, presence of collateral circulation, type and configuration of the aneurysm, and type of the dissection are important factors that predict the course of fusiform SCA aneurysms. We reviewed the literature on fusiform aneurysm of the SCA and report a further case treated surgically.

A plasma polymerization technique to overcome cerebrospinal fluid shunt infections.

Prosthetic devices, mainly shunts, are frequently used for temporary or permanent drainage of cerebrospinal fluid. The pathogenesis of shunt infection is a very important problem in modern medicine and generally this is characterized by staphylococcal adhesion to the cerebrospinal fluid shunt surfaces. In this paper, the prevention of the attachment of test microorganism Staphylococcus epidermidis on the cerebrospinal fluid shunt surfaces by 2-hydroxyethylmethacrylate (HEMA) precursor modification in the plasma polymerization system, is reported. Different plasma polymerization conditions (RF discharge power 10-20-30 W, exposure time 5-10-15 min) were employed during the surface modification. The surface chemistry and topology of unmodified and modified shunts was characterized by x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Also, static contact angle measurements were performed to state the change of surface hydrophilicity. All samples were tested in vitro with Staphylococcus epidermidis. A plasma-polymerized HEMA film (PP HEMA) was found to be an alternative simple method to decrease the microorganism attachment and create bacterial anti-fouling surfaces. The attachment of the model microorganism Staphylococcus epidermidis on the shunt surface modified by PP HEMA at 20 W and 15 min was reduced 62.3% if compared to the unmodified control surface of the shunt.

Neurosurgical practice at Baskent University, Turkey: a new model.

BACKGROUND: The Turkish Organ Transplantation and Burn Foundation was established in 1980. This was followed by the founding of the Turkish Transplantation and Burn Foundation Hospital in 1985. Under the aegis of this foundation and the Haberal Educational Foundation, Baskent University (BU) was founded in 1993 by Professor Mehmet Haberal, general surgeon and pioneer of organ transplantation in Turkey, and the President of the university since then. METHODS AND FINDINGS: The BU Neurosurgery Department began functioning in January of 1995, with the advancement of the department and with contributions from the other hospitals in cities of Adana, Konya and Alanya. Just 13 years after its foundation, BU became one of the most prestigious universities of the country. While establishing new neurosurgery units within BU health care facilities, the neurosurgeons appointed to the new center spend few months in the neurosurgery department at the BU Ankara Hospital, central hospital, at first in order to get acquainted with the BU medical system. After the new neurosurgery unit begins to operate, senior neurosurgeons from Ankara are called to supervise junior colleagues during major surgical procedures. In addition to these exchanges, residents are sent routinely to these centers as part of the neurosurgical residency programme. As the system is very integrated, neurosurgeons from other centers of the BU also routinely come to Ankara Hospital and Research Center for educational purposes. CONCLUSION: BU as a whole and its health system model in particular are certainly unique in Turkey. The statistical data from all hospitals of the BU reveal growing patient demand and consumer satisfaction.

Treatment of hydrocephalus with functionally isolated ventricles.

Rapid therapeutic drainage of one lateral ventricle may lead to ipsilateral slit ventricle, and the resultant functional obstruction of cerebrospinal fluid flow through the foramen of Monro may cause dilatation of the contralateral ventricle. Drainage of the lateral ventricle with a low-pressure shunt led to functionally isolated contralateral ventriculomegaly in this report. The patient's condition was complicated by a Candida albicans shunt infection. Following effective treatment of the infection by chemotherapy and removal of the shunt system, the patient was treated by bridging two lateral ventricles with ventricular catheters connected to an Ommaya reservoir. An occipital ventricular catheter was then inserted and connected to a programmable valve to drain the bridged lateral ventricles. Modern centers, caring for patients with infantile hydrocephalus, should have endoscopic facilities available but in cases with extensive ventricular adhesions and in asymmetric hydrocephalus where endoscopic septostomy between the ventricles is impossible our described technique may be used.

[Hemicentral retinal artery occlusion associated with moyamoya syndrome]. / Hemizentralarterienverschluss bei Moyamoya-Syndrom.

Moyamoya syndrome is a rare cerebrovascular disorder characterized by bilateral progressive supraclinoidal stenosis or occlusion of the internal carotid artery and development of collateral vessels in the lenticulostriate region. The syndrome manifests itself in association with another disease or other clinical symptoms. We present the case of a 12-year-old girl with hemicentral retinal artery occlusion due to moyamoya syndrome associated with clinical and laboratory findings of presumed systemic lupus erythematosus.

Sacral kyphoplasty for relieving pain caused by sacral hemangioma.

STUDY DESIGN: Case report describing sacral kyphoplasty in a patient with sacral hemangioma; the first account of this procedure in a sacral hemangioma. OBJECTIVES: To highlight the advantages of sacral kyphoplasty in the treatment of sacral tumors. SETTING: This study is made in Baskent University in Turkey. SUMMARY OF BACKGROUND DATA: Kyphoplasty and sacroplasty are new, minimally invasive techniques that are mostly used for treating osteoporotic vertebral body fractures. These techniques are very effective for achieving rapid pain relief and stabilizing the vertebra, and biopsy collection can be included in the procedure. The latter allows for informed treatment planning in patients with metastatic tumors. METHOD: A 74-year-old woman with known metastatic renal cell carcinoma was investigated for pain in the left sacral region. A tumoral lesion was detected, and sacroplasty was performed at S1. RESULTS: The sacral pain resolved completely after the procedure, and the patient was able to walk without assistance. The pathological diagnosis for the vertebral lesion was hemangioma. CONCLUSIONS: Sacral kyphoplasty is a very effective, minimally invasive surgical procedure. Patients with debilitating diseases such as primary sacral tumors or metastases can be treated by this technique with no significant complications.

Spontaneous corynebacterium discitis in a patient with chronic renal failure.

STUDY DESIGN: Case report describing spontaneous Corynebacterium diptheria discitis in a patient with chronic renal failure. OBJECTIVES: To describe this very rare form of discitis and the results of surgical and antibiotic therapy. SETTING: University Department of Neurosurgery, Turkey. CASE REPORT: A 55-year-old man with chronic renal failure presented with acute low-back pain. Lumbar magnetic resonance imaging (MRI) suggested discitis and osteomyelitis at the L5-S1 level. The L5-S1 disc was operated upon and the discectomy material was sent for pathological and microbiological analysis. RESULTS: Pathological examination revealed infection and bacterial culture grew C. diptheria. The patient was prescribed combination antibiotic therapy with vancomycin, a third-generation cephalosporin, and rifampicin. Clinical status improved after 8 weeks of therapy. Lumbar MRI revealed remission of the discitis and osteomyelitis after 10 months of follow-up. CONCLUSION: Chronic renal failure patients with low-back pain should be investigated for spinal infection. These individuals are prone to low-grade infection in the form of discitis or osteomyelitis. Corynebacterium subspecies rarely cause spontaneous discitis. This case is interesting because of the unusual causal organism and the occurrence of discitis in the setting of chronic renal failure.

Early effects of mild brain trauma on the cytoskeletal proteins neurofilament160 and MAP2, and the preventive effects of mexilitine.

OBJECTIVE: The aims were to investigate the early effects of graded, closed, mild head injury on neurofilament protein (NF160) and microtubule-associated protein-2 (MAP2) and to examine the levels of lipid peroxidation and the impact of mexilitine, inhibitor of lipid peroxidation, pretreatment on tissue damage. MATERIAL AND METHOD: One hundred and twenty-six rats were divided into groups as follows: Group 1 (n = 14) were controls; group 2 (n = 56) sustained trauma alone; and group 3 (n = 56) were pretreated with mexilitine (50 mg/kg). Groups 2 and 3 were subdivided into subgroups (n = 14 each), which were subjected to 100 g/cm2, 125 g/cm2, 150 g/cm2, and 175 g/cm2 trauma forces, respectively. Two hours after trauma, the frontal lobes from all groups were removed and processed for lipid peroxidation H&E staining, immunofluorescent labelling of neurofilaments and microtubules with anti-NF160 and anti-MAP2 antibodies. RESULTS: Compared to control findings, all the trauma-only animals showed increased lipid peroxidation levels and the elevations paralleled the amount of force applied. Administration of mexilitine significantly reduced the level of lipid peroxidation. In NF160 stainings, in group 2, the degree of impairment in axonal organization paralleled the different levels of force that were applied. Groups 3C and 3D (mexilitine pretreated) showed well-preserved axons and intact perikarya. In MAP2 stainings group 2 animals showed remarkably less MAP2 staining throughout the sections. There were no significant differences in MAP2 staining intensity or pattern among the group 2 subgroups. In contrast, in the sections from the group 3 animals, the level of MAP2 positivity was markedly preserved. CONCLUSION: In conclusion, our results show that the cytoskeletal proteins we investigated have different capacities for resisting injury, and that MAP2 is more vulnerable to injury than NF160. One of the reason for this cytoskeletal disruption may be increased lipid peroxidation. Inhibition of lipid peroxidation by pre-treatment with 50-mg/kg mexilitine significantly reduces the level of lipid peroxidation and may protect MAP2 and NF160 integrity in closed mild head injury. This protection is inversely proportional to the magnitude of the applied force.

The value of expanded polytetrafluoroethylene in preventing early re-ossification after craniosynostosis surgery: an experimental animal study in the rat.

BACKGROUND: Early re-ossification at the suturectomy site after craniosynostosis surgery remains an important problem. Many surgical methods have been used to address this, including placement of various types of absorbable and non-absorbable material between the bone edges at the site. This experimental study investigated the value of expanded polytetrafluoroethylene (ePTFE) membrane as a barrier to calvarial reclosure after craniosynostosis surgery in rats. METHOD: Thirty-five 2-week-old Sprague-Dawley rats were divided into two groups. In Group A (n = 17), ePTFE membranes were placed in the defect formed by a left coronal suturectomy. The Group B rats (n = 18) underwent left coronal suturectomy only. Animals were sacrificed at 1, 2 and 4 months postoperatively. In each case, the skull was removed and the operative site was examined for fibrosis, new bone formation, bone bridging, neovascularization and inflammatory response. FINDINGS: The two groups were similar with respect to neovascularization and new bone formation. By the end of the fourth postoperative month, 50% of the Group B specimens showed fibrosis and 50% showed bridging between the bone edges at the suturectomy site. In contrast, at the same stage in Group A, only 16.6% of the specimens exhibited a small amount of fibrosis, and none showed bone bridging between the edges. INTERPRETATION: Expanded PTFE is one of the most inert materials used in surgery. The study showed that inserting ePTFE membrane as a barrier between the bone edges at the suturectomy site prevents early re-ossification after craniosynostosis surgery in rats.

Spontaneous resolution of lumbar vertebral eosinophilic granuloma.

Eosinophilic granuloma (EG) is a rare disease but is more common in adults than children. It's often self-limiting. Spinal involvement is rare. It is the localized and most benign form of Langerhans' cell histiocytosis (previously known as histiocytosis X), characterised by lytic lesions in one or more bones. Spontaneous resolution of vertebral body lesions is very rare. In this case, the patient had one EG in a cervical vertebra and a similar lesion in a lumbar vertebra. This case is important because it featured a symptomatic lesion in the cervical spine accompanied by an asymptomatic lesion in a lumbar vertebra. We treated the cervical lesion by surgical fusion and followed the lumbar lesion up conservatively, with the patient in a corset. After 8 years of follow-up, control MRI showed that the lumbar lesion had spontaneously resolved.

Magnetic resonance image findings and surgical considerations in T1-2 disc herniation.

OBJECTIVE: To report a case of disc herniation at T1-2. CLINICAL PRESENTATION: A 57-year-old man presented with hand weakness, Horner's syndrome, and pain radiating along the medial aspect of one upper extremity. Magnetic resonance imaging demonstrated extruded T1-2 disc herniation with upward herniation of a sequestrated fragment. INTERVENTION: An anterior approach was used to excise the disc, that was compressing the spinal cord and the T1 nerve root. All the patient's symptoms resolved completely, including Horner's syndrome. CONCLUSION: Anterior discectomy may be the simplest and most effective method for disc excision and relief of spinal cord and T1 nerve root compression.

Activated protein C resistance and false type 2 protein C deficiency detected after multiple shunt failures in a patient with hydrocephalus.

A 2-year-old hydrocephalic boy who had suffered multiple shunt failures was evaluated for hypercoagulability after a thrombus was removed from his right atrium. The work-up revealed that the patient had the heterozygous form of activated protein C resistance and false type 2 protein C deficiency by the clotting method. His protein C activity was normal by the chromogenic method. We suggest that patients having hydrocephalus, shunt-associated thrombus formation, or both should be evaluated for thrombophilic disorders, and protein C activity should be measured by chromogenic assay in patients with documented activated protein C resistance.

Lumbar myxopapillary ependymoma mimicking neurofibroma.

OBJECTIVE: To report a case of lumbar myxopapillary ependymoma in whom neuroradiological and surgical findings strongly suggested neurofibroma. CLINICAL PRESENTATION: The patient presented with a 2 year history of progressive monoparesthesia and monoparesia of his right leg. He reported having minimal fecal and urinary incontinence. INTERVENTION: Total resection of the tumor was achieved by total L1-L2 laminectomies. There was no attachment to the spinal cord and dura. CONCLUSION: In spite of contemporary sophisticated neuroradiological facilities, we may still have diagnostic difficulties in some spinal tumors.

Systemic administration of mexiletine for attenuation of cerebral vasospasm following experimental subarachnoid haemorrhage.

Mexiletine is a class Ib drug that is widely used to treat ventricular arrhythmias. This compound is mainly known as a sodium channel blocker, but studies have demonstrated that it can also activate ATP-sensitive K+ channels and block Ca2+ channels. Recent in vitro data from experiments on liposomes indicate that mexiletine is also a potent antioxidant. The unique activity profile of this drug raised the possibility that it might be of benefit in limiting cerebral vasospasm. Our first series of experiments assessed the effects of mexiletine on transclivally exposed rabbit basilar arteries. The arteries were treated with 50-mM KCl, 20-nM endothelin-1 (ET-1), or 100-microM lysophosphatidic acid (LPA) in the presence or absence of 400-mM mexiletine. Vasoconstriction caused by KCl, ET-1, and LPA was inhibited by mexiletine. In a second series of experiments, subarachnoid haemorrhage (SAH) was induced in rabbits by injecting 3-ml of autologous arterial blood into the cisterna magna. Forty-eight hours after SAH induction, transclivally exposed basilar arteries exhibited a spastic constriction that was partially reversed by topical application of 400-microM mexiletine. In a third set of experiments, mexiletine was administered orally at dosages of 80-, 20, and 5-mg/kg/day t.i.d., beginning 3 hours before SAH to study the prevention of vasospasm. In a separate group of animals, 80- and 20-mg/kg/day t.i.d. of mexiletine was administered 21 hours post-SAH induction, to study the reversal of vasoconstriction. Microscopic analysis of vessels from controls (no SAH), SAH-only, and SAH + mexiletine groups indicated there was 71.43% vascular constriction in the SAH-only group compared with controls. Considerable vasorelaxation was seen in the prevention study, in which average arterial cross-sectional areas were reduced by only 17.86% and 39.29% in the mexiletine 80- and 20-mg/kg/day groups, respectively, compared with controls (p < 0.001). Compared with controls, average arterial cross-sectional areas were reduced by 53.58% and 64.29% in the mexiletine 80- and 20-mg/kg/day reversal groups, respectively. Our findings indicate that mexiletine induces potent relaxation in cerebrovascular arteries contracted with various agents, and that it prevents and partially reverses SAH-induced vasoconstriction.