Neurosurgery
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During carotid endarterectomy (CEA), phenylephrine infusions are commonly used to induce hypertension during carotid clamping in an attempt to increase collateral cerebral blood flow and prevent cerebral ischemia. Although this practice appears to increase the incidence of intraoperative myocardial ischemia during CEA when general anesthesia is employed, whether the limited use of phenylephrine infusions in specific instances of cerebral ischemia, as shown on an electro-encephalogram, results in low perioperative rates of both myocardial infarction (MI) and cerebral infarction remains unclear. We studied 171 CEAs done under general anesthesia performed with selective shunting based on the identification of cerebral ischemia by a two-channel computerized electroencephalographic monitor. ⋯ Two non-Q wave MIs (1.2%) occurred, both nonfatal. There were two cerebral infarctions (1.2%) and three deaths not related to MI (1.8%). Based on these findings, in order to decrease the incidence of both MI and cerebral infarction after general anesthesia for CEA, we recommend the restrictive use of phenylephrine-induced hypertension for specific instances of slowly or poorly reversible cerebral ischemia, as shown on the electroencephalogram.
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The direct surgical treatment of intracranial aneurysms is not always possible, especially in posterior circulation aneurysms. This is usually because of their complex anatomy and location next to the skull base and brain stem, where proximal vascular control is usually not attainable. Four patients at our institution underwent intraoperative transfemoral catheterization of the basilar artery with a nondetectable endovascular balloon for proximal control of the basilar artery. ⋯ All patients made a complete recovery except for initial postoperative third nerve palsies in three patients. This technique achieves intraoperative control of the basilar artery proximal to an aneurysm by the use of a nondetachable occlusive balloon in the basilar artery. An added benefit is the ease with which intraoperative angiography can be obtained in this context.(ABSTRACT TRUNCATED AT 250 WORDS)
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Biography Historical Article
Localization of sensorimotor cortex: the influence of Sherrington and Cushing on the modern concept.
According to Penfield, the work of Charles Sherrington's laboratory forced a change from the long-held concept of a broad, overlapping sensorimotor cortex to the concept of a narrow, discrete pre-Rolandic motor cortex separate from the post-Rolandic sensory strip. Harvey Cushing, one of the founders of modern neurosurgery, coined the term narrow motor strip. ⋯ In this article, we review the historical evolution of and the evidence for the concept of narrow and discrete motor and sensory strips anterior and posterior to the Rolandic cortex. A review of the historical development of the concept and recent physiological studies reaffirms the proposition that the motor and sensory areas are much broader and more complex than they were thought to be in the classic teaching that originated with Sherrington and Cushing.
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The authors describe a case of supratentorial bilateral arteriovenous malformations in a patient who suffered an intracerebral hemorrhage. It was radiologically demonstrated that the arteriovenous malformations were separate and bilateral, located in the temporal lobes. They were removed in two operations with preoperative embolization of one. The patient did well with no neurological damage.
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We report a rare incidence of sacral agenesis occurring in siblings. One of our patients had a low-lying conus, and untethering of the cord in the area of the filum terminale led to improvement in urinary symptoms. The need for aggressive investigation of patients with sacral agenesis and static neurological deficits is discussed.