World Neurosurg
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Rupture is the most serious consequence of cerebral aneurysms, and its likelihood depends on nonmodifiable and modifiable risk factors. Recent efforts have focused on analyzing the effects of hemodynamic forces on the initiation, growth, and rupture of cerebral aneurysms. Studies of the role of hemodynamics in the physiopathology of intracranial aneurysms fall between mechanical engineering and molecular biology. ⋯ The size of the aneurysm dome is the most common parameter used in clinical practice to estimate the risk of rupture. However, relying only on aneurysm size means excessively simplifying a more complicated reality. Aneurysms emerge in areas of the vascular wall exposed to high wall shear stress. The direction in which blood flows once an aneurysm forms depends on aspects such as neck diameter, its angle with respect to the parent artery, the parent vessel caliber, the caliber or the angle of efferent vessels, and aneurysm shape. The progression and rupture of aneurysms have been associated with zones of the aneurysm wall exposed to both high and low wall shear stresses. Advances in this challenging and growing field are intended to predict more precisely the risk of rupture of aneurysms and to better understand the mechanisms of origin and growth of aneurysms.
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Multicenter Study
Use of diffusion weighted imaging in differentiating between malignant and benign meningiomas. A multicenter analysis.
Meningioma is the most frequent intracranial tumor and is often an incidental finding on imaging. Some imaging-based scores were suggested for differentiating low- and high-grade meningiomas. The purpose of this work was to compare diffusion-weighted imaging findings of different meningiomas in a large multicenter study by using apparent diffusion coefficient (ADC) values for predicting tumor grade and proliferation potential. ⋯ The estimated threshold ADC value of 0.85 can differentiate grade I meningioma from grade II and III tumors. The same ADC value is helpful for detecting tumors with high proliferation potential.
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Multicenter Study
Steroid Use For Acute Spinal Cord Injury in Latin America: A Potentially Dangerous Practice Guided by Fear of Lawsuit.
Current international guidelines do not recommend the routine administration of methylprednisolone (MP) in patients with acute spinal cord injury (SCI). Its use is known to be associated with complications and death. ⋯ Despite increasing evidence against the routine administration of MP in patients with SCI and international guidelines that do not recommend its use, this potentially dangerous practice remains common on this continent. The Latin American medical associations need to produce guidelines to standardize practices with acute SCI. Moreover, educational campaigns might reduce practices guided mainly by misperception of legal issues instead of clinical benefit.
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The anatomic area delineated medially by the lateral part of the L4-L5 vertebral bodies, distally by the anterior-superior surface of the sacral wing, and laterally by an imaginary line joining the base of the L4 transverse process to the proximal part of the sacroiliac joint, is of particular interest to spine surgeons. We are referring to this area as the lumbo-sacro-iliac triangle (LSIT). Knowledge of LSIT anatomy is necessary during approaches for L5 vertebral and sacral fractures, sacral and iliac tumors, and extraforaminal decompression of the L5 nerve roots. ⋯ Improving anatomic knowledge of the LSIT may help surgeons decrease the risk of possible complications. When LSIT pathology is present, a lateral approach corresponding to the tip of the L4 transverse process, medially, is suggested to decrease the risk of vessel and nerve root damage.
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Clinical Trial
Long-term, continuous intra-arterial nimodipine treatment of severe vasospasm following aneurysmal subarachnoid hemorrhage.
Secondary vasospasm and disturbances in cerebrovascular autoregulation are associated with the development of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage. An intra-arterial application of nimodipine has been shown to increase the vessel diameter, although this effect is transient. The feasibility of long-term, continuous, intra-arterial nimodipine treatment and its effects on macrovasospasm, autoregulation parameters, and outcome were evaluated in patients with refractory severe macrovasospasm. ⋯ In well-selected patients with prolonged severe macrovasospasm, continuous intra-arterial nimodipine treatment can be applied as a rescue therapy with relative safety for more than 2 weeks to prevent secondary cerebral ischemia. The induced impairment of cerebrovascular autoregulation during treatment seems to have no negative effects.