The diffusion of water molecules inside organic tissues is often anisotropic (1). Namely, if there are aligned structures in the tissue, the apparent diffusion coefficient (ADC) of water may vary depending on the orientation along which the diffusion-weighted (DW) measurements are taken. In the late 1980s, diffusion-weighted imaging (DWI) became possible by combining MR diffusion measurements w...

A theoretical model is presented that simulates the thermal effects of laser radiation incident on biological tissue. The multiple scattering and absorption of the laser beam and the thermal diffusion process in the tissue are evaluated by a numerical technique that is well suited for microcomputers. Results are compared with recent empirical observations.

Anomalous diffusion is applicable in environments that are not locally homogeneous, such as human brain tissue. In such environments the model of restricted diffusion commonly employed in the analysis of diffusion magnetic resonance data is not valid. Anomalous diffusion displays a nonlinear time dependence for the mean-squared displacement, and provides a prediction of a stretched exponential ...

Modern challenges of food science require a new understanding of the determinants of food quality and safety. Application of advanced imaging modalities such as magnetic resonance imaging (MRI) has seen impressive successes and fast growth over the past decade. Since MRI does not have any harmful ionizing radiation, it can be considered as a magnificent tool for the quality control of food prod...

background and purpose: disc herniation leading to radiculopathy is one of the important differential diagnosis of low back pain which needs specific medical care. radiculopathies can be initially diagnosed by history taking and physical examination. however role of other diagnostic methods like magnetic resonance imaging (mri) and electromyography (emg) in narrowing differential diagnosis is w...

multiple sclerosis (ms) is a chronic inflammatory disease that leads to degeneration of the brain and spinal tissue. imbalances of cd4+ t cells including thelper1 (th1)/thelper2 (th2) and thelper17 (th17)/tregulatory (treg), their secreted cytokines and gene expressions, are important aspects of in immunopathogenesis of ms. vitamin a and its metabolites can regulate the immune system and appear...

background iron-loaded cardiac complication is the essential cause of mortality in patients with thalassemia. early detection and treatment of cardiac over-load can reduce mortality. objectives the current study aimed to evaluate the relationship between serum ferritin levels and t2* magnetic resonance imaging (mri) of heart and liver and liver iron concentration (lic) to diagnose iron over loa...

background: the purpose of this study was to evaluate the dependency of magica polymer gel dosimeter response (r2) on different electron energies as well as on different mean dose rate for a standard clinically used linear accelerator. materials and methods: the sensitivity of the dosimeter was represented by the slope of calibration curve in the linear region measured for each modality. a cali...

background: in this work investigation of the normoxic pagat polymer gel dosimeter such as sensitivity, the r2-dose response with post time and the percentage depth dose (pdd) of pagat polymer gel dosimeter have been undertaken. materials and methods: using mri, the formulation to give the maximum change in the transverse relaxation rate r2 was determined to be 4.5% n,n'-methylenbis- acryl...