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Matthew M. Grabowski, Pablo F. Recinos, Amy S. Nowacki, Jason L. Schroeder, Lilyana Angelov, Gene H. Barnett and Michael A. Vogelbaum

, 22 While most within the field of neurooncology agree that maximal resection of the tumor offers the best chance for prolonged survival, the impact of extent of resection (EOR) on survival continues to be a point of discussion. 15 Previous studies have used both CT and MRI to try to determine EOR and its implications for survival in GBM patients. Although there are no definitive prospective studies that have shown that EOR alone alters survival, there is a substantial volume of retrospective literature that has shown that maximizing EOR likely extends time to

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pressure (ICP) were increased in comparison with those in control individuals or those SAH cases without a raised ICP. 1 It is possible that ANF may be implicated as a regulator of the brain sodium and water balances, but the data may also be interpreted as being caused by an increased CSF outflow resistance leading to an accumulation of the hormone. In experimental animals, intraventricular administration of ANF accelerated the volume regulatory efflux of sodium from the brain and prevented the increase in brain water in response to a systemic hypoosmolar volume load

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Gene H. Barnett, Donald W. Kormos, Charles P. Steiner and Joe Weisenberger

display showing localization of the left parieto-occipital tumor. Neuroimaging Three-dimensional (3-D) volume sets of either CT or MR imaging data are obtained that encompass the surgical field and the fiducials. Images are interpolated into a volume data set containing voxels of dimensions of 1.25 mm or less. The fiducials are identified and the Cartesian coordinates within this reference coordinate set are recorded. Images are presented in a triplanar format (simultaneous coronal, sagittal, and transverse views) with one or more windows available for

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Symeon Missios, Kimon Bekelis and Gene H. Barnett

directionality of thermal energy deposition allows for “sculpting” of the laser thermal effect and conformal laser thermal coagulation of asymmetrical tumors. Histological Changes Induced by LITT Heat creates tissue necrosis via both acute and chronic effects that include edema, neuronal swelling, and cell membrane disruption. 43 Heat-induced tissue necrosis results from temperature increase above 43°C. 33 The combination of tissue necrosis and edema may result in an increase in the volume of the treated lesion. 45 The edema is resorbed and after approximately 1 week

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Gene H. Barnett, David W. Miller and Joseph Weisenberger

with the long axis oriented craniocaudally so as to span the CT slices. For magnetic resonance (MR) imaging, the fiducial sites are marked with indelible ink, and proprietary or commercial MR imaging—compatible fiducial markers are affixed to the skin at these locations. Fig. 1. Drawing demonstrating the typical application of fiducial markers to allow wide spacing, yet flexible head orientation and Mayfield fixation device placement. Imaging Data Three-dimensional volume sets consisting of either CT or MR imaging data encompassing the surgical field and the

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Narendra Nathoo, Marc R. Mayberg and Gene H. Barnett

must pump the intravenous injected blood through the pulmonary circulation and then out into the aorta, before the heart itself can benefit. Believing that the primary function of the heart was to maintain a normal level of pressure in the elastic aorta and that patients in severe shock who were given intravenous fluids would experience an additional strain on an already ischemic heart, he thought that intraarterial infusion of fluids would restore the cerebral and coronary blood flow more rapidly before the burden of an increase in venous pressure and blood volume

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Symeon Missios, Kimon Bekelis, Gasser Al-Shyal, Peter A. Rasmussen and Gene H. Barnett

metrics have been used to determine the appropriate prescribed dose during SRS for AVMs. One of the most widespread methods utilizes the K index, 14 first introduced in 1997 by Karrlson et al. at the Karolinska Institute, Sweden. The K index was calculated as the ratio of the margin dose over the cube root of the AVM volume, and a K index of approximately 27 appeared to be optimal to obtain AVM obliteration with minimal risk of complications. 14 It was derived from the notion that an AVM was, in essence, a collection of parallel pipes, the length of which were related

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Andrew A. Kanner, Michael A. Vogelbaum, Marc R. Mayberg, Joseph P. Weisenberger and Gene H. Barnett

working volume between the two magnets' disks. No scalp-based fiducial markers are applied and no preoperative imaging is necessary. After the initial imaging session, which should incorporate a long sequence with thin slices (3 mm), the registration process is initiated. Repeated registration is possible if relative movement of patient to magnet is suspected. The accuracy of navigation has been previously reported 37 and we found it to be adequate for both control of the resection and guidance for stereotactic brain biopsy. There are two navigational strategies that

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Michael A. Vogelbaum, Cathy Brewer, Gene H. Barnett, Alireza M. Mohammadi, David M. Peereboom, Manmeet S. Ahluwalia and Shenqiang Gao

, which are rigid and have small diameter delivery tips distally and larger diameter shafts proximally. 10 This design allows these devices to be placed stereotactically to specific locations in the brain, but they can be used only intraoperatively due to the risk of injury from dislodgement or breakage in a nonsecured patient. These types of catheters have been shown to produce backflow-resistant CED, but infusions are limited to only a few milliliters of volume due to the time limitations associated with their restriction to intraoperative use only and due to their

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Michael A. Vogelbaum, Cathy Brewer, Gene H. Barnett, Alireza M. Mohammadi, David M. Peereboom, Manmeet S. Ahluwalia and Shenqiang Gao

, which are rigid and have small diameter delivery tips distally and larger diameter shafts proximally. 10 This design allows these devices to be placed stereotactically to specific locations in the brain, but they can be used only intraoperatively due to the risk of injury from dislodgement or breakage in a nonsecured patient. These types of catheters have been shown to produce backflow-resistant CED, but infusions are limited to only a few milliliters of volume due to the time limitations associated with their restriction to intraoperative use only and due to their