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William S. Anderson, Eric H. Kossoff, Gregory K. Bergey and George I. Jallo

frequently undergo surgery for the placement of subdural monitoring electrodes, which are sometimes also used as stimulation leads to better delimit eloquent cortex. In the present article we describe the recent implantation of a responsive stimulation device that has the capability of both detecting new-onset seizures and applying stimulation near a seizure focus in an effort to quash the detected seizure. For 1 of our 7 patients, the implantation procedure is described in detail. In 1954 Penfield and Jasper 23 first reported the use of electrical stimulation as a tool

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Jee Soo Jang, Won Bok Lee and Hansen A. Yuan

I n terms of providing stability transpedicular screw fixation has been identified as a superior method compared with that conferred by anterior instrumentation and posterior hook/rod devices when used in an unstable spine. 1, 7 Several investigators have studied and characterized the anatomical measurements of the thoracic vertebrae to assess possibilities for proper screw insertion into the pedicle with minimal complications. 2–5, 11–16, 18 Pedicle screw insertion in the thoracic spine is a technically challenging procedure because of the small pedicle

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Victor Garcia-Navarro, Guido Lancman, Amancio Guerrero-Maldonado, Vijay K. Anand and Theodore H. Schwartz

of firm tumors in a narrow working space without heating the surrounding tissue. Methods Equipment and Principles We used such a side-cutting aspiration system called the NICO Myriad (NICO Myriad System, NICO Corp.). The device is available in 3 lengths (10, 13, and 25 cm) and 2 cannula diameters (1.9 and 2.5 mm). The handpiece is shown in Fig. 1 . The mechanism at the tip is based on a device that acts as an aspirator, tissue rake, and scissors. It is a disposable, nonheat-generating tissue removal system. It has an outer stationary cannula and a blunt

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Chien-Jen Hsu, Yi-Wen Chang, Wen-Ying Chou, Chou-Ping Chiou, Wei-Ning Chang and Chi-Yin Wong

measure the ROM in healthy adults using an electromagnetic tracking device. We also analyze the relative contribution of the thoracic spine, the lumbar spine, and the hip to trunk movements. Clinical Material and Methods Mathematical Model A 3D kinematic trunk model with an electromagnetic tracking device was developed for this study. The functional segments of the cervical, thoracic, and lumbar spine and the hip were defined. There were 4 coordinate systems, including 1 for the thoracic spine, lumbar spine, hip, and thigh. Because the standing position was

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André Olivier and Gilles Bertrand

T he orthogonal stereotaxic approach in neurosurgery was developed by A. Mussen around 1918 (unpublished material). Talairach, et al. , 1 designed a double-grid system which also permits an orthogonal approach, that is, at a right angle to the frame and parallel to the central x-ray beam. Such a system facilitates introduction of intracerebral electrodes and biopsy needles by the lateral approach. Safety and accuracy are provided by angiography. For the last 4 years, we have used a compact stereotaxic device of our own design that can be adapted to a

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Christian Bowers, Amin Amini, Andrew T. Dailey and Meic H. Schmidt

S pinal fusion has been the standard of treatment for spinal instabilities due to degenerative changes in the disc with subsequent spondylolisthesis, ankylosis, and central canal and neuroforaminal stenosis. Although fusion devices have been shown to offer improved outcomes, some long-term clinical data fail to show a correlation between the high rate of fusion and pain improvement. 9 , 11 Biomechanical alteration in the load-transferring and stress-shielding effect, causing higher morbidity at the adjacent levels, instrumentation-related osteopenia, and a

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Donald Horton and Michael Pollay

T he flow characteristics of the first commercially available anti-siphon valve, designed as an anti-siphon device (ASD) for ventricular shunting, were reported by Portnoy, et al. , 15 in 1973. In the present paper, we discuss a similar device that has some advantages over the earlier ASD when used in conjunction with presently available differential-pressure valves for the treatment of hydrocephalus. The necessity for control of cerebrospinal fluid (CSF) outflow from the ventricular system while the patient is in an upright position has been appreciated for

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Jee Soo Jang, Sang Ho Lee and Sang Rak Lim

T he authors of several biomechanical studies have demonstrated that anterior cage-assisted stabilization alone does not ensure solid fixation especially in extension and axial rotation. 2, 8, 9 Supplementary posterior fixation, such as that provided by translaminar or pedicle screws after ALIF, is needed for solid fixation. We introduce a new, minimally invasive procedure for the percutaneous insertion of PTFSs following ALIF in which a specially designed guide device is used. The object of this study was to evaluate the accuracy and efficacy of this method

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Clemens M. Schirmer, Daniel A. Hoit and Adel M. Malek

) 2 (33) <0.82  previous radiation 2 (5) 1 (5) 1 (8) 0 <0.74  hx of myocardial ischemia 25 (63) 11 (50) 9 (75) 5 (83) <0.18 * Values represent numbers of patients (%) unless otherwise specified. CEA = carotid endarterectomy; gen = generation; hx = history; SD = standard deviation. † Guidant Accunet in 3 procedures and SpiderFX in 3 procedures. The FilterWire EX Distal Protection Device The fixed-basket FilterWire EX DPD consists of a distal polyurethane filter with pores sized between 80 and 100 μm that is mounted

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Karim ReFaey, Kaisorn L. Chaichana, Anteneh M. Feyissa, Tito Vivas-Buitrago, Benjamin H. Brinkmann, Erik H. Middlebrooks, Jake H. McKay, David J. Lankford, Shashwat Tripathi, Elird Bojaxhi, Grayson E. Roth, William O. Tatum and Alfredo Quiñones-Hinojosa

ability to resect pathological tissue (tumor and/or epileptic focus) by the surgeon. 16 , 18 , 28 The currently used ECoG devices are available in several geometric forms, varying from the single strip electrode (1 × 4 cm or 1 × 6 cm) to the adjacent grid electrode block. 47 , 51 Since previous ECoG devices were restricted by technological limitations, these devices have physiological constraints. The strip electrode allows for the monitoring of epileptiform patterns in only one direction (i.e., superior, inferior, lateral, or medial) unless multiple strips are used