Clinical Applications Of Diffusion Tensor Imaging Research Articles

Application of diffusion tensor imaging (DTI) and MR-tractography in the evaluation of peripheral nerve tumours: state of the art and review of the literature.

Peripheral nerves can be affected by a variety of benign and malignant tumour and tumour-like lesions. Besides clinical evaluation and electrophysiologic studies, MRI is the imaging modality of choice for the assessment of these soft tissue tumours. Conventional MR sequences, however, can fail to assess the histologic features of the lesions. Moreover, the precise topographical relationship between the peripheral nerve and the tumor must be delineated preoperatively for complete tumour resection minimizing nerve damage. Using Diffusion tensor imaging (DTI) and tractography, it is possible to obtain functional information on tumour and nerve structures, allowing the assess anatomy, function and biological features. In this article, we review the technical aspects and clinical application of DTI for the evaluation of peripheral nerve tumours. (www.actabiomedica.it)

Current Clinical Applications of Diffusion-Tensor Imaging in Neurological Disorders.

Diffusion-tensor imaging (DTI) is a noninvasive medical imaging tool used to investigate the structure of white matter. The signal contrast in DTI is generated by differences in the Brownian motion of the water molecules in brain tissue. Postprocessed DTI scalars can be used to evaluate changes in the brain tissue caused by disease, disease progression, and treatment responses, which has led to an enormous amount of interest in DTI in clinical research. This review article provides insights into DTI scalars and the biological background of DTI as a relatively new neuroimaging modality. Further, it summarizes the clinical role of DTI in various disease processes such as amyotrophic lateral sclerosis, multiple sclerosis, Parkinson's disease, Alzheimer's dementia, epilepsy, ischemic stroke, stroke with motor or language impairment, traumatic brain injury, spinal cord injury, and depression. Valuable DTI postprocessing tools for clinical research are also introduced.

Diffusion tensor imaging and tractography of the sciatic and femoral nerves in healthy volunteers at 3T

BackgroundThe aim was to clarify the normal fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the sciatic and femoral nerves at the level of the hip joint and to visualize the neural tracts with diffusion tensor imaging (DTI).MethodsTwenty-four healthy volunteers (12 men and 12 women, age 20–29 years) underwent DTI for visualization with tractography and quantification of FA and ADC values on a 3 Tesla MRI (b value = 800 s/mm2, motion probing gradient, 11 directions, time to repeat/echo time = 9000/72.6 ms, axial slice orientation, slice thickness = 3.0 mm with no inter-slice gap, field of view = 320 × 320 mm, 96 × 192 matrix, 75 slices, number of acquisitions = 4). Regions of interest in the sciatic nerve were defined at the femoral head, the S1 root, and the midpoint levels. The femoral nerve was evaluated at 3–4 cm proximal to the femoral head level.ResultsThe tractography of the sciatic and femoral nerves were visualized in all participants. The mean FA values of the sciatic nerve were increased distally from the S1 root level, through the midpoint, and to the femoral head level (0.314, 0.446, 0.567, p = 0.001, respectively). The mean FA values of the femoral nerve were 0.565. The mean ADC values of the sciatic nerves were significantly lower in the S1 root level than in the midpoint and the femoral head level (1.481, 1.602, 1.591 × 10−3 × 10−3 mm2/s, p = 0.001, respectively). The ADC values of the femoral nerve were 1.439 × 10−3 mm2/s. FA and ADC values showed moderate to substantial inter- and intra-observer reliability without significant differences in gender or laterality.ConclusionVisualization and quantification of the sciatic and femoral nerves simultaneously around the hip joint were achieved in healthy young volunteers with DTI. Clinical application of DTI is expected to contribute to hip pain research.

Diffusion MR Imaging of White Matter Pathways

Diffusion tensor imaging (DTI) is one of the most promising MRI techniques for characterizing microstructural changes of cerebral white matter in brain research and clinical applications. The number of DTI studies is increasing, and more than 7500 articles have been published over the last decade. DTI enables visualization and characterization of white matter tracts in vivo by providing a unique image contrast on white matter that is unavailable with routine MR techniques; this allows three-dimensional (3D) visualization of neuronal pathways and quantification of the diffusion properties of white matter. Since its introduction in 1994, DTI has been used to study the structure of white matter and changes to its integrity within normal brains and brains affected by aging, stroke, dementia, psychiatric disorder, tumor, and other conditions. In this paper, the technical aspects and clinical applications of DTI are reviewed with a focus on clinical use and in vivo studies. The strengths and weaknesses of the approach are discussed and current extensions of the technology (q-space imaging and diffusional kurtosis imaging) are summarized.

Update Clinical Application of Diffusion Tensor Imaging

Diffusion tensor imaging (DTI) is an effective technology for the study of the internal structure of the brain non-invasively. At present, this technology is widely applied to clinical diagnosis and can reflect a series of pathological changes in the microstructure due to changes in nerve fibers. This article first explains the basic principles of DTI and some parameters like fractional anisotropy (FA) and relative anisotropy (RA). It then reviews several clinical applications of DTI from three perspectives, namely the clinical applications of anisotropy indices, fibers tracking, and DTI combined with other neuroimaging methods. Through the studies of the changes in the parameters of DTI and the contrast among a series of white matter fiber images, researchers can obtain important information about the changes in the structure of tissues, which can in turn be applied in clinic, and also include the value of DTI in the work-up of diseases as a tool in the differentiation of normal tissues and diseased tissues. This article also reviews the clinical application of fiber tracking and DTI combined with functional magnetic resonance imaging (fMRI), electroencephalogram (EEG), and mangnetoencephalography (MEG), and others. Moreover, this article summarizes the advantages of DTI over traditional imaging technology like magnetic resonance imaging (MRI) and diffusion weighted imaging (DWI). Some prospect applications of the DTI as well as unsolved problems are also briefly reviewed. Keywords: Brain tumor, diffusion tensor imaging, fiber tracking, magnetic resonance imaging, MEG, white matter fiber.

Diffusion-tensor imaging in brain tumors

Diffusion-tensor imaging (DTI) is the only novel imaging technique that is able to demonstrate white matter tracts and their structural changes related to different brain pathologies. Diffusion tensor describes the 3D diffusion phenomenon of the protons according to their microenvironmental properties allowing a unique description of the space where this molecular movement takes place. This model provides in vivo demonstration of the complex ultrastructural organization of the white matter as well as structural changes due to tumoral invasion. Current applications of DTI and magnetic resonance tractography allow accurate delineation of the eloquent white matter tracts and their relation with tumoral tissue. This article summarizes the basic physics and clinical applications of DTI in brain tumor diagnosis and follow-up. Effectiveness of different DTI metrics and magnetic resonance tractography is reviewed in tumor characterization, treatment planning and in the assessment of post-therapeutic changes. The ...

Application of the MRI diffusion tensor imaging for the astrocytic tumor in motor function area

Objective Astrocytic tumors in motor area often grow infihratively with worse outcome. It is significant to identify the tumor infiltrating field before the operation to improve the outcome of surgery. Diffusion tensor imaging(DTI) is an advanced quantitative form of diffusion-weighted imaging. The study is to discuss the clinical application of DTI in identifying, forecasting the grades of astrocytoma and choosing the best procedure for resecting astrocytoma. Method The clinical data of consecutive 33 patients with astrocytoma in motor function area underwent DTI examination before the operation. Results Compared with normal brain tissue, significant differences of ADC and FA were found in solid area of astrocytoma necrotic region, edema region(P<0.05). Significant differences of ADC were also found in solid tumor compared with necrotic region and edema region respectively(P<0.05). By the imaging guidance of DTI, we could show white matter fiber tracts of the motor area and evaluate the relationship between astrocytoma and white matter fiber for the operation. Conclusions ADC and FA can be used to differentiate normal brain tissue from astrocytoma. According to the change of white matter fiber tracts around the tumors in DTT, we could optimize the operational project and improve the resection of astrocytoma significantly, as well as to decrease potential disability after operation. Key words: Astrocytoma; Diffusion magnetic resonance imaging

Imaging white matter diffusion changes with development and recovery from brain injury

Purpose: This study reviews the application of diffusion tensor imaging (DTI) to the study of developmental and pathological changes in brain white matter. The ability to measure and monitor such changes in vivo would provide important opportunities for charting disease progression and monitoring response to therapeutic intervention. This study first reviews the use of DTI in studying normal human brain development. It goes on to illustrate how DTI has been used to provide insights into recovery from damage in selected brain disorders.Conclusions: It is concluded that potential clinical applications of DTI include: (i) monitoring pathological change, (ii) providing markers that predict recovery and allow for individual targeting of therapy, (iii) providing outcome measures, (iv) providing measures of potentially compensatory structural changes and (v) improving understanding of normal brain anatomy to aid in interpretation of the consequences of localized damage.