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Takumi Abe, Kinya Oshida, Kiyoshi Matsumoto, Masataka Iida and Naoko Sanno

S omatostatinomas are rare endocrine tumors that were first described in 1977; 1, 4 few cases have been reported. 2, 3 Somatostatinomas are located mainly in the pancreas, but they can also present in extrapancreatic organs such as the duodenum. 2 Metastases or local invasion are seen most frequently in the liver and lymph nodes. 2, 3 Other sites of metastasis include the peritoneum, skin, bone, kidney, ovary, adrenal gland, and thyroid gland. 3 To our knowledge, metastasis from a pancreatic somatostatinoma to the brain has not been previously described

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Patrick F. Golden and John A. Jane

since not only are altered states of consciousness regularly noted but also there is a tendency for perfusion of the heart and brain to be maintained in many diverse situations at the expense of other organs, as for instance, in the diving reflex. 2, 7, 14, 15 It is interesting to note recent work on the role of the nervous system in shock and the regulation of circulation. 1, 4, 5, 11, 13 Previous Study We have previously reported the technique of experimentally exaggerating this physiologically selective perfusion of the heart, lungs, and brain, and have

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Claudia Faria, José Miguéns, João Lobo Antunes, Duarte Salgado, Sofia Nunes, Cândida Barroso, Maria do Carmo Martins, Vasco Moura Nunes and Lúcia Roque

P ediatric brain tumors are the most common form of solid neoplasms in children and represent a major challenge to all oncologists. Malignant brain neoplasms represent the leading cause of cancer deaths in patients between 0 and 14 years of age. Moreover, benign tumors do not always have a good outcome, and about 10 to 20% of the cases recur and show progressive disease. 1 , 9 Cancers arise due to a multistep accumulation of genomic changes in cells, which confers on them a phenotype characterized by uncontrolled cell growth, apoptosis resistance, genomic

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Raghu Raghavan, Martin L. Brady, María Inmaculada Rodríguez-Ponce, Andreas Hartlep, Christoph Pedain and John H. Sampson

M otivated in part by the profound difficulties associated with improving treatment for glio-blastoma multiforme, many people have been exploring positive-pressure infusion as a means of delivering therapeutic agents into the brain. Pioneered by researchers at the NIH in the US, 22 , 27 , 28 CED of an agent through the interstitial space provides a means of achieving therapeutic drug concentrations within the parenchymal tissues on a regional basis, without the limitations imposed on delivery by the BBB. In the prototypical version of such an approach

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Michael A. Weitzner, Christina A. Meyers and Kevin Byrne

experience of patients with brain tumors is unique, and they have not been adequately studied. Brain tumors are often disabling and fatal. Mortality rates from brain tumors have increased substantially over the last decades, especially among the elderly in most developed countries. Whether such trends reflect a rise in brain cancer risk is controversial. 11, 16 Even though primary brain tumors account for less than 2% of all malignancies, they are second only to stroke as the leading cause of death from neurological disease. 2, 7, 27 The estimate is that 74% of brain

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Russell R. Lonser, Stuart Walbridge, Alexander O. Vortmeyer, Svetlana D. Pack, Tung T. Nguyen, Nitin Gogate, Jeffery J. Olson, Aytac Akbasak, R. Hunt Bobo, Thomas Goffman, Zhengping Zhuang and Edward H. Oldfield

clinical, laboratory, radiographic, molecular, and histological analyses of these animals up to 10 years after WBRT is described. Materials and Methods Animal Groups All animal experiments were performed in accordance with the National Institutes of Health guidelines on the use of animals in research and were approved by the Animal Care and Use Committee of the National Institute of Neurological Disorders and Stroke. We used a total of 12 3-year-old male primates (Macaca mulatta) . All animals underwent fractionated WBRT while sedated (see Whole-Brain

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Douglas W. Laske, Paul F. Morrison, Daniel M. Lieberman, Mark E. Corthesy, James C. Reynolds, Patricia A. Stewart-Henney, Sung-Soo Koong, Alex Cummins, Chang H. Paik and Edward H. Oldfield

B ecause of the difficulty of delivering high molecular mass proteins, such as targeted protein toxins, cytokines, neurotrophic factors, or enzymes, across the blood-brain barrier, delivery methods that introduce agents directly into the extravascular spaces of the central nervous system are often used. These methods include intraventricular or intrathecal injection, direct parenchymal injection, use of polymer implants, and intracavitary instillation. However, slow interstitial diffusion within the tissue interstices limits the ability of these approaches to

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Dennis R. Groothuis, Sherman Ward, Andrea C. Itskovich, Cosmin Dobrescu, Cathleen V. Allen, Cynthia Dills and Robert M. Levy

C ompared with the vasculature of many other organs, the normal blood-brain barrier (BBB) severely restricts the passage of most drugs from plasma to the extracellular space, with more than an 8-log difference in the entry rate of small lipid-soluble molecules compared with large proteins. In some brain diseases the BBB is functionally defective, resulting in increased transcapillary transport rates. For example, the rate of blood-to-brain transfer (that is, permeability) is increased in many brain tumors. 13 However, the magnitude of the increase is regionally

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A. John Popp

often is my inspiration and who always is my better half. The Theme of the 2004 Annual Meeting of the AANS The theme of the 2004 Annual Meeting, “Advancing Patient Care Through Technology and Creativity,” focuses our attention on the concordance between the science of neurosurgery and the art necessary to practice it with mastery in the service of our patients. At the core of our art resides our respect for our patients and a profound interest and curiosity regarding the brain—the intriguing organ that is the focus of our profession—about which we have learned

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Nathan McDannold, Yongzhi Zhang and Natalia Vykhodtseva

T hermal ablation via MRI-guided focused ultrasound (FUS) is an emerging minimally invasive alternative to resection and radiosurgery. 4 , 18 , 23 While the use of FUS ablation has a long history, 3 , 26 , 32 the advent of large-scale phased array systems and aberration correction methods that have enabled transmission through the intact human skull 2 , 7 , 8 and MRI methods to quantify temperature changes 21 have renewed interest in this technology for use in the brain. Transcranial MRI-guided FUS is now being investigated clinically for thermal