La Radiologia medica
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Lung sonography, generally not thought to be diagnostic, is currently being reconsidered and is developing into an interesting clinical possibility. The principal sonographic signs of lung disease are described in light of our personal experience and the current literature.
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La Radiologia medica · Apr 2006
ReviewMagnetic resonance diffusion-weighted imaging: extraneurological applications.
Diffusion-weighted (Dw) imaging has for a number of years been a diagnostic tool in the field of neuroradiology, yet only since the end of the 1990s, with the introduction of echoplanar imaging (EPI) and the use of sequences capable of performing diffusion studies during a single breath hold, has it found diagnostic applications at the level of the abdomen. The inherent sensitivity to motion and the magnetic susceptibility of Dw sequences nonetheless still create problems in the study of the abdomen due to artefacts caused by the heartbeat and intestinal peristalsis, as well as the presence of various parenchymal-gas interfaces. With regard to focal liver lesions, a review of the literature reveals that Dw imaging is able to differentiate lesions with high water content (cysts and angiomas) from solid lesions. ⋯ In particular, no significant difference in ADC is noted between normal hypercellular bone marrow and hypercellular bone marrow secondary to lymphomatous infiltration whereas this difference is significant between hypocellular, normocellular and haematopoietic hypercellular bone marrow. With regard to the study of joints, the limited structure dimensions, particularly cartilage, creates technical difficulties related to spatial resolution and an adequate signal-to-noise ratio, problems that can only be solved by further technological developments. Lastly, a significant difference in ADC values between degenerative and inflammatory effusion has been found, a fact that may be explained as the result of the activity of hyaluronidase present in inflammatory forms, which causes a reduction in the concentration of hyaluronic acid with a consequent decrease in viscosity.
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La Radiologia medica · Sep 2005
Review Comparative StudyMultidisciplinary management of the solitary pulmonary nodule (SPN): our opinion.
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La Radiologia medica · Mar 2005
ReviewDiffusion-weighted MR of the brain: methodology and clinical application.
Clinical diffusion magnetic resonance (MR) imaging in humans started in the last decade with the demonstration of the capabilities of this technique of depicting the anatomy of the white matter fibre tracts in the brain. Two main approaches in terms of reconstruction and evaluation of the images obtained with application of diffusion sensitising gradients to an echo planar imaging sequence are possible. The first approach consists of reconstruction of images in which the effect of white matter anisotropy is averaged -- known as the isotropic or diffusion weighted images, which are usually evaluated subjectively for possible areas of increased or decreased signal, reflecting restricted and facilitated diffusion, respectively. ⋯ Diffusion changes might be a more sensitive marker for progression of the disease than conventional imaging findings. In neurodegenerative diseases of the central nervous system such as Alzheimer's disease, Huntington's disease, hereditary ataxias and motor neuron disease, quantitative diffusion MR demonstrates the cortical and subcortical grey matter damage, which is reflected in a regional increase of D or ADC, but also reveals the concomitant white matter changes that are associated with an increase in D or ADC and decrease in FA. In all these diseases the diffusion changes are correlated to the clinical deficit and are potentially useful for early diagnosis and longitudinal evaluation, especially in the context of pharmacological trials.