Journal of neurosurgery
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Journal of neurosurgery · Jul 1997
Case ReportsValidation of the optic nerve sheath response to changing cerebrospinal fluid pressure: ultrasound findings during intrathecal infusion tests.
Raised intracranial pressure leads to increased pressure around the optic nerve (ON), which underlies the formation of papilledema and the enlargement of the dural optic nerve sheath (ONS). In clinical practice, the presence of widened ONSs is demonstrable on neuroimaging, but their relationship to cerebrospinal fluid (CSF) pressure remains unknown. The authors investigated the ONS response to pressure during CSF absorption studies in 12 patients undergoing neurological testing. ⋯ It is concluded that the human ONS has sufficient elasticity to allow a detectable dilation in response to intracranial hypertension. Because of a variable pressure-diameter relationship, the subarachnoid pressure cannot be predicted exactly by single scans. Therefore, the clinical relevance of this method relies on the demonstration of pathologically enlarged sheaths or ongoing enlargement on serial ultrasonography studies.
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Journal of neurosurgery · Jul 1997
Seizures induced by intracerebral injection of thrombin: a model of intracerebral hemorrhage.
The coagulation cascade plays an important role in brain edema formation caused by intracerebral blood. In particular, thrombin produces brain injury via direct brain cell toxicity. Seizures and increased cerebral electrical activity are commonly associated with intracerebral blood and are possible effects of thrombin leading to cell injury in the brain. ⋯ There was no evidence of seizure activity on EEG monitoring when alpha-NAPAP was injected along with the thrombin. In addition, the artificial clots containing thrombin produced agitation and a circling tendency in the rats, along with brain edema. These results indicate that the coagulation cascade is involved in seizure production and increased brain electrical activity, which contribute to the neurological deficits and brain edema formation that are seen with intracerebral hemorrhage.
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Journal of neurosurgery · Jun 1997
Case ReportsVentriculofemoroatrial shunt: a viable alternative for the treatment of hydrocephalus. Technical note.
Children with shunted hydrocephalus often have a myriad of other medical conditions. When these concomitant problems involve the pleura, peritoneum, and/or the venous system, placement of the distal catheter may prove to be problematic. This report presents preliminary results in three hydrocephalic children following ventriculofemoroatrial shunt placement. ⋯ Fluoroscopic guidance was used to confirm the intraatrial position of the distal end of the shunt catheter. Follow-up review to date shows no complications. This newly described technique provides a feasible alternative to distal shunt catheter placement in patients in whom more traditional sites are unavailable.
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Journal of neurosurgery · Jun 1997
Anaplastic ependymoma: treatment of pediatric patients with or without craniospinal radiation therapy.
The authors conducted a retrospective review of the clinical and treatment characteristics and outcomes in 28 pediatric patients with anaplastic ependymoma treated with radiation therapy since the advent of computerized tomography (CT) (1978-1994). Twelve patients received craniospinal irradiation followed by a boost to the primary site, two received whole-brain radiation therapy followed by a boost to the primary site, and the remaining 14 were treated with focal radiation therapy. The mean dose to the primary site was 5486 cGy. ⋯ The significance of anaplastic histological classification is controversial. Differences in the disease-free and overall survival rates have been demonstrated between ependymomas and anaplastic ependymomas treated in the pre-CT era. The results of this study show that there is no benefit from craniospinal irradiation in this group of patients.