Neurosurgery
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Among the many possible mechanisms of the secondary spinal cord injury (SCI), microcirculatory disturbances as a result of activated leukocyte-induced endothelial cell injury is important because it is potentially treatable and reversible. Currently, clinically available pharmacological agents for treatment of acute SCI do not inhibit neutrophil activation. The effect of antithrombin III (AT-III) on neutrophil activation was studied in rats with SCI produced with an aneurysm clip on the T2-T7 segments. ⋯ The results demonstrate that AT-III treatment may reduce secondary structural changes in damaged rat spinal cord tissue by inhibiting leukocyte activation.
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The resection of intramedullary spinal cord lesions (ISCLs) can be complicated by neurological deficits. Neuromonitoring has been used to reduce intraoperative risk. We have used somatosensory evoked potentials (SEPs) and muscle-derived transcranial electrical motor evoked potentials (myogenic TCE-MEPs) to monitor ISCL removal. We report our retrospective experience with the addition of free-running electromyography (EMG). ⋯ During resection of ISCLs, free-running EMG can supplement motor tract monitoring by TCE-MEPs. Segmental and suprasegmental elicitation of neurotonic discharges can be observed in four-limb EMG. Abnormal electromyographic bursts, tonic discharge, or abrupt electromyographic silence may anticipate myogenic TCE-MEP loss and predict a postoperative motor deficit.
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To describe the effects of ventralis oralis anterior (VOA) and posterior (VOP), as well as ventralis intermedius (VIM), deep brain stimulation (two ipsilateral thalamic leads implanted) on posttraumatic Holmes tremor. Results of both thalamic lesioning and thalamic deep brain stimulation for Holmes tremor and tremors due to posttraumatic lesions in the region of the midbrain have been disappointing. In 2001, the use of two electrodes implanted in parallel for severe essential tremor was reported. We propose the use of a similar technique for posttraumatic Holmes tremor. One rationalization for the placement of two leads was to affect both the cerebellar receiving area (VIM) and the pallidal receiving area (VOA/VOP). A second rationalization was that the placement of a second electrode may affect somatotopy, and may, therefore, be beneficial for the treatment of more difficult to control tremor subtypes. ⋯ The patient experienced tremor rebound with VIM-VOP monotherapy. However, when the second lead (VOA/VOP) was activated, he experienced sustained improvement in tremor and tremor disability at a 12-month follow-up examination. This case elucidates a potential new approach for the treatment of patients with posttraumatic Holmes tremor. Additional study and longer follow-up periods will be needed to further evaluate this promising therapy.
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Prepontine retroclival tumors have typically been removed through a variety of anterolateral, lateral, and posterolateral cranial base approaches. Here, we describe an endonasal transclival cranial base approach for removal of prepontine epidermoid tumors. ⋯ The endonasal approach offers a minimally invasive, anatomically direct route for removing prepontine epidermoid tumors that obviates brain retraction. The use of angled endoscopes is essential for gaining lateral, cephalad, and caudal visualization to augment the limited microscope view. Inadequate repair of clival dural defects remains the greatest potential pitfall in attempting transsphenoidal transclival tumor removal.