Stereotactic and functional neurosurgery
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Stereotact Funct Neurosurg · Jan 2007
Clinical TrialSubthalamic nucleus stimulation in Parkinson's disease patients intolerant to levodopa.
Levodopa responsiveness has been shown to be the best predictor of improvement after subthalamic nucleus (STN) deep brain stimulation (DBS) for Parkinson's disease (PD). The objective of this study was to assess the effect of STN DBS on PD patients intolerant to levodopa due to severe acute side effects such as intolerable nausea. There were 10 patients in the study who received STN DBS for PD. ⋯ Patient global ratings also indicated significant improvements at all follow-up visits. There were no differences in stimulator settings between the two groups at the 3-, 6- or 12-month follow-up visits. In conclusion, although levodopa responsiveness is the best predictor for outcome after STN DBS, carefully selected PD patients intolerant to levodopa can have significant improvement.
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Stereotact Funct Neurosurg · Jan 2007
Case ReportsHistopathology of radiation necrosis with severe peritumoral edema after gamma knife radiosurgery for parasagittal meningioma. A report of two cases.
Gamma knife radiosurgery (GKS) has been an effective treatment for meningiomas. Nevertheless, it still has certain risks. We present 2 cases of parasagittal meningioma after GKS complicated with radiation necrosis and peritumoral edema. The results of histologic examination are discussed. ⋯ After radiosurgery peritumoral edema tends to occur in meningiomas with a parasagittal position. Radiation necrosis, infiltration of inflammatory cells, and radiation injury to the vasculature causing hyalinization of blood vessels are suggested as the underlying histopathology.
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Stereotact Funct Neurosurg · Jan 2007
Comparative StudyComparison of accuracy and precision between frame-based and frameless stereotactic navigation for deep brain stimulation electrode implantation.
The accuracy and precision of frameless neuronavigation as compared to conventional frame-based stereotaxy for implantation of deep brain stimulation (DBS) electrodes were studied in 14 patients with essential tremor. DBS electrodes were implanted bilaterally in the ventrolateral thalamus [ventrointermediate nucleus (VIM)] in one procedure. Frameless neuronavigation was used on one side and the conventional frame-based technique on the other. ⋯ At clinical follow-ups, tremor reduction was similar irrespective of the implantation technique. It is concluded that conventional frame-based stereotaxy has higher accuracy/precision for hitting a small brain target than the frameless technique. However, the difference is relatively small and does not influence the clinical result of DBS electrode implantations in the VIM when treating tremor.
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Stereotact Funct Neurosurg · Jan 2007
Clinical TrialHypofractionated stereotactic radiotherapy using intensity-modulated radiotherapy in patients with one or two brain metastases.
A small fraction of patients with 1-2 brain metastases will not be suitable candidates to either surgical resection or stereotactic radiosurgery (SRS) due to either their location or their size. The objective of this study was to determine the local control, survival, patterns of relapse and the incidence of brain injury following a course of hypofractionated stereotactic radiotherapy while avoiding upfront whole brain radiation therapy (WBRT) in this subgroup of patients. ⋯ The preliminary results of hypofractionated SRS are comparable to both surgery and SRS data for solitary brain metastases in terms of local control and overall survival with acceptable morbidity in this cohort of unfavorable patients.
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Stereotact Funct Neurosurg · Jan 2007
Comparative Study Clinical TrialRegional cerebral perfusion differences between periventricular grey, thalamic and dual target deep brain stimulation for chronic neuropathic pain.
Regional cerebral blood flow changes were evaluated in different subcortical brain targets following deep brain stimulation (DBS) for chronic pain. Three patients with intractable neuropathic pain were assessed; one had stimulating electrodes in the ventroposterolateral thalamic nucleus (VPL), one in the periventricular grey (PVG) area, and one had electrodes in both targets. Pain relief was achieved in all patients. ⋯ Furthermore, thalamic and dual target DBS increased thalamic perfusion, yet PVG DBS decreased perfusion in the PVG-containing midbrain region and thalamus. Dual target stimulation decreased anterior cingulate and insular cortex perfusion. The study demonstrates regional differences in cerebral perfusion between three accepted and efficacious targets for analgesic DBS.