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Dennis A. Velez, Marc R. Mayberg and William H. Ludlam

. Definition of Cyclic CS Although not identified in most large series of patients with CS, the presence of cyclic CS is being increasingly recognized as a clinical entity. 18 Its diagnosis, although challenging, can be made by demonstrating three peaks and two troughs of cortisol production. 2 There are no available data to date that define what minimal biochemical threshold should be used to establish the diagnosis of cyclic CS. In general, however, the tests results used to document episodes of hypercortisolemia in cyclic CS will be similar to those of

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Juan C. Fernandez-Miranda, Johnathan A. Engh, Sudhir K. Pathak, Ricky Madhok, Fernando E. Boada, Walter Schneider and Amin B. Kassam

performed the surgical trajectory planning. The x, y, and z coordinates for the cannulation entry point and the target were recorded on high-definition structural T1-weighted image space. A simulated endoscopic port (cylinder 8 mm in diameter, with starting center point at preselected x, y, and z coordinates as entry point and center of tumor as end point) was created and imported into TrackVis 25 as a region of interest to estimate the fiber damage associated with the planned transfrontal approach ( Fig. 4 ). This trajectory ( Fig. 4A, C, and E ) was theoretically

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James M. Drake, Ash Singhal, Abhaya V. Kulkarni, Gabrielle DeVeber, D. Douglas Cochrane and The Canadian Pediatric Neurosurgery Study Group

Pediatric and Congenital Heart Disease for complications after cardiac surgery for congenital heart disease, including consensus definitions. 2 There are, however, no standardized or consensus-driven definitions for complications or adverse events in pediatric neurosurgery. We recently reported the incidence of complications from all surgical procedures in a single pediatric neurosurgical center prospectively over a 2-year period. 12 It became clear that broadening this approach to other centers would require standardized definitions to ensure accuracy and

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Benjamin K. Hendricks, James S. Yoon, Kurt Yaeger, Christopher P. Kellner, J Mocco, Reade A. De Leacy, Andrew F. Ducruet, Michael T. Lawton and Justin R. Mascitelli

assessed the treatment of WNAs, there is no universally accepted definition. Historically, a WNA was first defined in 1994 as an aneurysm with a neck diameter ≥ 4 mm. 8 The geometrical features of a WNA that correlated with coiling success led to an expansion of the definition to include aneurysms with a dome-to-neck ratio of < 2 in 1998 and < 1.5 in 2000. 6 , 7 However, these definitions have not been used consistently to define WNAs in the neurosurgical literature. In many instances, the term has been generalized to include any aneurysm requiring adjunctive

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The Chiari I malformation

JNSPG 75th Anniversary Invited Review Article

Samuel G. McClugage III and W. Jerry Oakes

. Clearly, many different etiologies can cause cerebellar tonsillar descent with or without syrinx formation, and it is reasonable to consider these as separate entities from CIM, rather than focusing on their final common consequence of caudal tonsillar displacement. FIG. 2. Intraoperative intradural exposure of the craniocervical junction dorsally, showing an arachnoid veil causing fourth ventricular outlet obstruction, after initial exposure ( left ) and after opening of the veil to relieve the obstruction ( right ). Figure is available in color online only. Definition

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E. Sander Connolly Jr. and Richard G. Ellenbogen

T ator and colleagues present data on 284 consecutive patients, referred over 16 years, who were diagnosed with a concussion. Of these 284 patients, 221 (an extremely high 78% of the patients) were diagnosed with postconcussion syndrome (PCS). 1 The PCS diagnosis was based on a newly refined definition that includes persistence of at least 3 symptoms for more than a month. The principal aim of this study was to redefine the term PCS based on a more detailed review of the authors' experience. The average age of the patients was 27 years old and two

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Mary Lee Vance

The authors review the literature regarding the definition, clinical features, origin, pathophysiology, and diagnosis of cyclic Cushing syndrome (CS). They suggest that it is increasingly recognized as a clinical entity. Periodic hormonogenesis due to endocrine tumors and variable hormone secretion, including hypersecretion, in healthy individuals is known to occur. The medical literature contains well-documented cases of a few patients with episodic hypersecretion of cortisol. One limitation of these reports is that many of the patients underwent

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Gene H. Barnett, Mark E. Linskey, John R. Adler, Jeffrey W. Cozzens, William A. Friedman, M. Peter Heilbrun, L. Dade Lunsford, Michael Schulder, Andrew E. Sloan and The American Association of Neurological Surgeons/Congress of Neurological Surgeons Washington Committee Stereotactic Radiosurgery Task Force

extracranial disease than to their intracranial disease. Recently there has been a spate of reports attempting to clarify or to (re)define the terms “stereotactic radiosurgery” and “stereotactic radiotherapy” (SRT). 1 , 48 , 66 It has become increasingly clear that the evolution of radiosurgery and radiotherapeutic techniques demands a reevaluation of the definition of radiosurgery by organized neurosurgery. These factors led the American Association of Neurological Surgeons (AANS) and the Congress of Neurological Surgeons (CNS) to form the Stereotactic Radiosurgery Task

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Ghassan K. Bejjani

With the widespread use of newer neuroimaging techniques and modalities, significant tonsillar herniation is being diagnosed in more than 0.5% of patients, some of whom are asymptomatic. This puts the definition of the adult Chiari malformation to the test. The author provides a historical review of the evolution of the definition of the adult Chiari malformation in the neurosurgery, radiology, and pathology literature.

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Mark B. Frenkel, Casey D. Frey, Jaclyn J. Renfrow, Stacey Q. Wolfe, Alexander K. Powers and Charles L. Branch Jr.

in their Methods section. We have identified multiple variations in the definition of LL throughout the literature, and hypothesize that these variations may impact the conclusions and clinical decision making that derives from this measurement. In this paper we attempt to determine how pervasive the variability of the definition of LL is within the current spine literature. Methods Search Strategy A literature search of PubMed was conducted by searching for the term “Lumbar Lordosis” in the Title, Keyword, and/or Abstract fields. The search was restricted to