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Yu-Li Lee, Shu-Tian Chen, Jen-Tsung Yang, Hsu-Huei Weng, Hsueh-Lin Wang and Yuan-Hsiung Tsai

intervention. Recently, several studies have revealed the existence of microstructural changes in TN patients with NVCS using diffusion tensor imaging (DTI), which showed a decreased fractional anisotropy (FA) and an increased apparent diffusion coefficient (ADC) and radial diffusivity (RD), as well as the trend of an FA reduction correlation using a visual analog scale (VAS) analysis. 5 Additionally, another study also showed a lower FA value at the affected REZ of trigeminal nerves with TN; moreover, this study further accessed DTI data and diffusivity metrics after

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Kalil G. Abdullah, Daniel Lubelski, Paolo G. P. Nucifora and Steven Brem

Images are acquired using a clinical MRI unit (1.5- or 3-T systems) with a standard head coil. Diffusion tensor imaging is performed using a single-shot EPI sequence. Echo planar imaging is a fast acquisition technique that reduces motion-related artifacts. Single-shot EPI is commonly used instead of multishot EPI despite its poorer spatial resolution, because it has a shorter acquisition time, a superior signal-to-noise ratio, and less motion-related distortion. 1 These techniques have enabled a fast acquisition time of less than 5 minutes. 52 The degree of

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Liat Ben-Sira, Noam Goder, Haim Bassan, Shlomi Lifshits, Yaniv Assaf and Shlomi Constantini

imaging (DTI) is an advanced MRI technique that characterizes white matter by quantifying the 3D diffusion properties of water in tissue. In white matter, diffusion is anisotropic, meaning that it is free along the path of the fibers and hindered perpendicular to them. Structural components, such as axonal membranes and myelin, significantly influence the anisotropic diffusion of water. Therefore, alterations in DTI parameters are believed to reflect the level of structural integrity of tissue. 3 , 4 , 10–12 Diffusion tensor imaging extracts the principal diffusivities

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Khader M. Hasan, Ambika Sankar, Christopher Halphen, Larry A. Kramer, Linda Ewing-Cobbs, Maureen Dennis and Jack M. Fletcher

semiautomatically stripped to remove nonparenchymal tissue. Diffusion weighted data were distortion–corrected using the mutual information maximization approach. 54 The details of DT image processing are described elsewhere. 7 , 38–40 Diffusion Tensor Imaging–Derived Metrics Fractional anisotropy is a measure of the intravoxel directionality of water translational random motion in the presence of barriers and is expressed as a ratio ranging from 0 to 1 (0 = isotropic or no predilection for any particular direction, and 1 = unidirectional). Although the underlying

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Chi Heon Kim, Chun-Kee Chung, June Sic Kim, Tae Ahn Jahng, June Ho Lee and In Chan Song

. Pathological diagnoses were as follows: 15 cases of astrocytoma, three lymphomas, one anaplastic ependymoma, one ganglioglioma, one meningioma, and one brain abscess. One patient with a brain abscess was treated only with antibiotics, because his lesion was small (diameter 2 cm) and located in a deep brain area. Regions of Interest Diffusion tensor imaging findings were analyzed quantitatively. We designed two different types of regions: an ovROI in the center of the pyramidal tract, which was located in the region most adjacent to the maximal brain lesion diameter

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Cormac G. Gavin and H. Ian Sabin

focused on using separately acquired tractography images and fusing them with stereotactic treatment images in order to analyze dosimetry to critical fiber tracts and improve treatment planning. 11 , 12 , 13 This process has also been recently reported using other radiosurgical platforms. 5 , 16 The use of diffusion tensor imaging (DTI) has been reported to reduce the risk of motor complications after radiosurgery. 9 We present our method of integrating stereotactic DTI tractography into conventional treatment planning for GKRS. Methods Twenty patients who underwent

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Matilde Inglese, Sachin Makani, Glyn Johnson, Benjamin A. Cohen, Jonathan A. Silver, Oded Gonen and Robert I. Grossman

Because of these properties, diffusion tensor imaging represents a more promising approach to the characterization of microscopic brain damage. Furthermore, it has been shown to be a sensitive and early indicator of TBI. 3, 12, 24 Arfanakis, et al., 3 reported a reduction of fractional anisotropy in five patients with mild TBI within 24 hours of injury and suggested that fractional anisotropy changes might be an indicator of DAI. Moreover, fractional anisotropy values have been shown to correlate with several clinical outcome variables in patients with moderate

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Yaron A. Moshel, Robert E. Elliott, David J. Monoky and Jeffrey H. Wisoff

has decreased the incidence of postoperative deficits and has enabled complete resection and favorable long-term survival. 24 , 25 , 27 , 28 , 32 , 34 , 35 Diffusion tensor imaging and white matter tractography are relatively new additions to MR imaging, which exploit the preferential movement of water protons within the brain along the axis of axons. 40 The sensitivity of DT imaging to anisotropic movement of protons allows visualization of the larger white matter tracts on directionally encoded color maps and can provide quantitative measurements of the

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Thomas Anthony Gallagher, Neil G. Simon and Michel Kliot

. This review discusses the current approaches to measuring nerve injury and recovery, the evolution of diffusion tensor imaging (DTI) for the monitoring of nerve degeneration and regeneration, and illustrative clinical applications of DTI in the nerve injury clinic. Assessments in Nerve Injury Clinical and Electrodiagnostic Approaches Current approaches to diagnosing, quantifying, and monitoring peripheral nerve trauma include clinical assessment and electrodiagnostic studies, supplemented by imaging and intraoperative electrophysiological studies in

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Robert T. Buckley, Weihong Yuan, Francesco T. Mangano, Jannel M. Phillips, Stephanie Powell, Robert C. McKinstry, Akila Rajagopal, Blaise V. Jones, Scott Holland and David D. Limbrick Jr.

frontooccipital horn ratio, which was 0.59 for both the preoperative and postoperative scans. Postoperative sagittal cine phase-contrast CSF flow study (C) demonstrating flow through the ventriculostomy. Diffusion Tensor Imaging Preoperative and postoperative DTI data were acquired with a 1.5-T scanner (Signa, GE Healthcare). A diffusion-weighted spin echo sequence with single-shot echo planar imaging was used with the following specifications: field of view = 240 × 240 mm, matrix = 96 × 96, in-plane resolution = 2.5 × 2.5 mm, slice thickness = 2.5 mm, number of