Neurosurgery
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Terson's syndrome (vitreous hemorrhage) and other ocular hemorrhages (retinal hemorrhages) have been reported to occur in up to 40% of patients with ruptured cerebral aneurysms. Because microsurgical vitrectomy can safely restore vision in patients with visual loss secondary to Terson's syndrome, we hypothesized that prospectively screening a selected group of patients with aneurysms would result in a higher rate of vitrectomy in patients with more extensive subarachnoid hemorrhage. ⋯ Ophthalmological screening of patients with histories of transient or prolonged comas after ruptured cerebral aneurysms very sensitively identifies patients with ocular hemorrhages, which are relatively common in patients with subarachnoid hemorrhage treated in an academic neurosurgical practice. The present study underestimates the true incidence of Terson's syndrome in that patients who died shortly after their subarachnoid hemorrhage were not included. Vitrectomy for patients who do not exhibit spontaneous improvement in vision results in a dramatic reversal of blindness.
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To provide a theoretical basis for the selection of the anode-cathode configuration in spinal cord stimulation for the management pain when one percutaneous epidural electrode or two electrodes in parallel are used. ⋯ The relative positions of cathodes and anodes and their distance from the spinal cord are the major determinants of dorsal column/dorsal root activation and paresthesia distribution. The large interpatient variability of the intraspinal geometry is the main cause of differences in paresthesia coverage among patients having optimally placed electrode(s). Changes of paresthesia coverage over time are more probable when multiple electrodes are used.
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Intimate to the application of lateral transtemporal approaches to the cranial base are the identification, manipulation, and/or the sacrifice of the venous anatomy of the inferolateral temporal lobe and the superior petrosal sinus and the transection of the tentorium. This study demonstrates the relationship and variability of the venous drainage of the lateral and inferior surfaces of the temporal lobe. ⋯ An understanding of the complexity and diversity of the venous drainage complexes and their configurations is necessary to avoid venous complications during lateral cranial base surgery.
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The management of chronic pain of spinal origin continues to represent a challenge for neurosurgeons. Spinal cord stimulation for chronic intractable pain is an effective therapy in approximately 50% of patients. The present study uses a novel imaging approach, functional magnetic resonance imaging (fMRI), to examine the central effects of spinal cord stimulation. ⋯ This report is the first to describe the cerebral effects of exogenous spinal cord stimulation with fMRI. fMRI allows for the objective examination of the effects of DCS and may provide an objective means of evaluating the efficacy of DCS as a therapy for intractable pain of spinal origin.
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Case Reports
Contralateral and ipsilateral microsurgical approaches to carotid-ophthalmic aneurysms.
The vicinity of carotid-ophthalmic aneurysms to the roof of the cavernous sinus, to the anterior clinoid process, and to the optic nerve or the optic chiasm requires well-defined surgical techniques. Although microsurgical techniques with ipsilateral direct approaches to these aneurysms have been described in detail, studies about contralateral strategies for the microsurgical treatment of carotid-ophthalmic aneurysms are rare and are mainly confined to case reports. The aim of this study is to describe how to decide on the ipsilateral and contralateral microsurgical approaches to such aneurysms and to demonstrate the surgical techniques for the ipsilateral and contralateral exposure of carotid-ophthalmic aneurysms. ⋯ Giant carotid-ophthalmic aneurysms that are eligible for surgical treatment as well as small and large aneurysms dislocating the optic nerve or the chiasm superomedially or medially should be approached via ipsilateral craniotomies. It is recommended that small and large aneurysms of the carotid-ophthalmic segment originating medially, superomedially, or superiorly, displacing the optic nerve or the chiasm superiorly, superolaterally, or laterally, be approached via contralateral craniotomies.