Diffusion-weighted imaging (DWI) of the spleen in patients with liver cirrhosis and portal hypertension.

Objective: The purpose of this study was to assess the influence of liver cirrhosis and portal hypertension on diffusion coefficients of the spleen.

Material And Methods: We retrospectively evaluated 50 patients with liver cirrhosis and 50 patients without any history of liver disease who underwent magnetic resonance imaging of the upper abdomen, including echo planar diffusion-weighted imaging using b values of 50, 300 and 600mm(2)/s. Spleen apparent diffusion coefficient (ADC), liver ADC, muscle ADC and normalized spleen ADC (defined as the ratio of spleen ADC to muscle ADC) were compared between cirrhotic patients and patients in the control group and correlated with Child-Pugh stages.

Comparison of different mathematical models of diffusion-weighted prostate MR imaging.

Purpose: To evaluate which mathematical model (monoexponential, biexponential, statistical, kurtosis) fits best to the diffusion-weighted signal in prostate magnetic resonance imaging (MRI).

Materials And Methods: 24 prostate 3-T MRI examinations of young volunteers (YV, n=8), patients with biopsy proven prostate cancer (PC, n=8) and an aged matched control group (AC, n=8) were included. Diffusion-weighted imaging was performed using 11 b-values ranging from 0 to 800 s/mm(2).

Impact of blood flow on diffusion coefficients of the human kidney: a time-resolved ECG-triggered diffusion-tensor imaging (DTI) study at 3T.

Purpose: To evaluate the impact of renal blood flow on apparent diffusion coefficients (ADC) and fractional anisotropy (FA) using time-resolved electrocardiogram (ECG)-triggered diffusion-tensor imaging (DTI) of the human kidneys.

Materials And Methods: DTI was performed in eight healthy volunteers (mean age 29.1 ± 3.

Temporally resolved electrocardiogram-triggered diffusion-weighted imaging of the human kidney: correlation between intravoxel incoherent motion parameters and renal blood flow at different time points of the cardiac cycle.

Purpose: To evaluate the influence of pulsatile blood flow on apparent diffusion coefficients (ADC) and the fraction of pseudodiffusion (F(P)) in the human kidney.

Materials And Methods: The kidneys of 6 healthy volunteers were examined by a 3-T magnetic resonance scanner. Electrocardiogram (ECG)-gated and respiratory-triggered diffusion-weighted imaging (DWI) and phase-contrast flow measurements were performed.

Diffusion-attenuated MRI signal of renal allografts: comparison of two different statistical models.

Objective: Contrast-enhanced MRI is considered problematic in renal allograft recipients because of the development of nephrogenic systemic fibrosis. Therefore, we assessed the clinical value of a monoexponential model and a distribution function model of diffusion-weighted imaging (DWI) in renal allografts.

Materials And Methods: A total of 23 patients were divided into three groups, as follows: group A, stable renal allograft function for at least 6 months; group B, transplantation within the past 30 days, with good renal allograft function; and group C, an acute deterioration or decrease in renal allograft function.