Journal of neurosurgery
-
Journal of neurosurgery · Dec 2005
Early programmable valve malfunctions in pediatric hydrocephalus.
The use of adjustable differential pressure valves has been recommended to improve ventriculoperitoneal (VP) shunt performance in selected patients; however, published data are scarce regarding their clinical reliability. Recently, the identification of a number of malfunctioning programmable valves during shunt revision surgery in children prompted a retrospective review of valve performance in this patient cohort. ⋯ In this study the authors demonstrated an annualized intrinsic programmable valve malfunction rate of 11.1%, whereas during the same period no intrinsic valve malfunctions were noted with nonprogrammable valve systems for similar causes of hydrocephalus. The CSF protein levels did not correlate with observed valve malfunction rates. Further evaluation in a prospective, randomized fashion will elucidate specific indications for programmable valve systems and better determine the reliability of these valves in the pediatric population.
-
Journal of neurosurgery · Dec 2005
Attenuation of fluctuating striatal synaptic dopamine levels in patients with Parkinson disease in response to subthalamic nucleus stimulation: a positron emission tomography study.
The "wearing-off" phenomenon often hampers the treatment of Parkinson disease (PD). Although deep brain stimulation (DBS) of the subthalamic nucleus (STN) is known to ameliorate the wearing-off phenomenon, the mechanism by which it does this remains unclear. As part of an inquiry into the mechanism of STN DBS, the authors measured synaptic dopamine levels in the striatum by performing positron emission tomography (PET) with [11C]raclopride. ⋯ Deep brain stimulation of the STN induces the stabilization of synaptic dopamine concentrations in the striatum and may attribute to the alleviation of levodopa-related motor fluctuations.
-
Journal of neurosurgery · Dec 2005
Case ReportsA C1-2 locked facet in a child with atlantoaxial rotatory fixation. Case report.
Conservative treatment is reported in a child with atlantoaxial rotatory fixation. Three-dimensional (3D) computerized tomography (CT) and magnetic resonance (MR) imaging demonstrated the degree of dislocation and alar ligament damage. A rigid cervical collar and muscle relaxant agents without any traction allowed full recovery. Control 3D CT scanning and MR imaging findings are reported.
-
Journal of neurosurgery · Dec 2005
Local distribution and toxicity of prolonged hippocampal infusion of muscimol.
The activity of gamma-aminobutyric acid (GABA), the principal inhibitory neurotransmitter, is reduced in the hippocampus in patients with complex partial seizures from mesial temporal sclerosis. To provide preliminary safety and distribution data on using convection-enhanced delivery of agents to treat complex partial seizures and to test the efficacy and safety of regional selective neuronal suppression, the authors infused muscimol, a GABA-A receptor agonist, directly into the hippocampus of nonhuman primates using an integrated catheter electrode. ⋯ Targeted modulation of neuronal activity is a reasonable research strategy for the investigation and treatment of medically intractable epilepsy.