Journal of neurosurgery
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Journal of neurosurgery · Nov 2009
Subarachnoid hemorrhage and the distribution of drugs delivered into the cerebrospinal fluid. Laboratory investigation.
Investigators in experimental and clinical studies have used the intrathecal route to deliver drugs to prevent or treat vasospasm. However, a clot near an artery or arteries after subarachnoid hemorrhage (SAH) may hamper distribution and limit the effects of intrathecally delivered compounds. In a primate model of right middle cerebral artery (MCA) SAH, the authors examined the distribution of Isovue-M 300 and 3% Evans blue after infusion into the cisterna magna CSF. ⋯ Intrathecal drug distribution is substantially limited by SAH. Thus, when using intrathecal drug delivery after SAH, vasoactive drugs are unlikely to reach the arteries that are at the highest risk of delayed cerebral vasospasm.
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Journal of neurosurgery · Nov 2009
Case ReportsDural arteriovenous fistulas draining into the petrosal vein or bridging vein of the medulla: possible homologs of spinal dural arteriovenous fistulas. Clinical article.
Dural arteriovenous fistulas (DAVFs) with leptomeningeal venous reflux generally pose a high risk of aggressive manifestations including hemorrhage. Among DAVFs, there is a peculiar type that demonstrates direct drainage into the bridging vein rather than the dural venous sinus. The purpose of this study was to investigate the characteristics of DAVFs that drain directly into the petrosal vein or the bridging vein of the medulla oblongata. ⋯ Embryologically, both the petrosal vein and the bridging vein of the medulla are cranial homologs of the spinal cord emissary bridging veins that drain the pial venous network. The authors believe that DAVFs in these locations may be included in a single category with spinal DAVFs because of their similar clinical characteristics.
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Journal of neurosurgery · Nov 2009
Biography Historical ArticleRichard Lower (1631-1691): acknowledging his notable contributions to the exploration of the nervous system. Historical vignette.
Richard Lower (1631-1691), an anatomist and physician, was born in St. Tudy, Cornwall, England, and became an avid follower of William Harvey and a pupil to Sir Thomas Willis. Unfortunately, little is written of his contributions to the study of the nervous system despite his successful medical career and his regard as one of the most significant English physiologists of the 17th century. ⋯ Some have even attributed the results of Willis' anatomical and physiological studies to Lower rather than to Willis himself. Lower has not received the recognition he is owed as a highly skilled and trained anatomist and physician. In this paper, the neurological contributions, with a brief mention of challenges, delivered during the 17th century by this influential historical physician will be highlighted with an emphasis on the impact each contribution made.
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Journal of neurosurgery · Nov 2009
Dynamic imaging of a model of intracranial saccular aneurysms using ultra-high-resolution flat-panel volumetric computed tomography. Laboratory investigation.
Imaging of intracranial aneurysms using conventional multidetector CT (MDCT) is limited because of nonvisualization of features such as perforating vessels, pulsatile blebs, and neck remnants after clip placement or coil embolization. In this study, a model of intracranial saccular aneurysms in rabbits was used to assess the ultra-high resolution and dynamic scanning capabilities of a prototype flat-panel volumetric CT (fpVCT) scanner in demonstrating these features. ⋯ The spatial resolution, surface anatomy visualization, metal artifact profile, and 4D dynamic images from fpVCT are superior to those from MDCT. Flat-panel volumetric CT demonstrates aneurysm surface features to better advantage than angiography and is comparable to angiography in metal artifact profile. Even though the temporal resolution of fpVCT is not quite as good as that of angiography, fpVCT images yield clinically important anatomical information about aneurysm surface features and posttreatment neck remnants not attainable with either angiography or MDCT images.
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Journal of neurosurgery · Nov 2009
Equal contribution of increased intracranial pressure and subarachnoid blood to cerebral blood flow reduction and receptor upregulation after subarachnoid hemorrhage. Laboratory investigation.
Cerebral ischemia remains the key cause of disability and death in the late phase after subarachnoid hemorrhage (SAH), and its pathogenesis is still poorly understood. The purpose of this study was to examine whether the change in intracranial pressure or the extravasated blood causes the late cerebral ischemia and the upregulation of receptors or the cerebral vasoconstriction observed following SAH. ⋯ This study revealed that both the elevation of intracranial pressure and subarachnoid blood per se contribute approximately equally to the late CBF reductions and receptor upregulation following SAH.