Post-processing of dynamic gadolinium-enhanced magnetic resonance imaging exams of the liver: explanation and potential clinical applications for color-coded qualitative and quantitative analysis

Abstract

The purpose of this article is to explain and illustrate the current status and potential applications of automated and color-coded post-processing techniques for the analysis of dynamic multiphasic gadolinium-enhanced magnetic resonance imaging (MRI) of the liver. Post-processing of these images on dedicated workstations allows the generation of time-intensity curves (TIC) as well as color-coded images, which provides useful information on (neo)-angiogenesis within a liver lesion, if necessary combined with information on enhancement patterns of the surrounding liver parenchyma. Analysis of TIC and color-coded images, which are based on pharmacokinetic modeling, provides an easy-to-interpret schematic presentation of tumor behavior, providing additional characteristics for adequate differential diagnosis. Inclusion of TIC and color-coded images as part of the routine abdominal MRI workup protocol may help to further improve the specificity of MRI findings, but needs to be validated in clinical decision-making situations. In addition, these tools may facilitate the diagnostic workup of disease for detection, characterization, staging, and monitoring of antitumor therapy, and hold incremental value to the widely used tumor response criteria.

Focal nodular hyperplasia of the liver: diffusion and perfusion MRI characteristics

“…On PWI, two different time-signal intensity curve shapes, classified according to the schemes described in the literature [5,6], were observed: type 1, showing quick and marked enhancement (Fig. 2) and quick decay, followed by a slowly decaying plateau, and type 2, characterized by fast enhancement followed by slowly decaying plateau.…”

“…Because most pathologic entities of the liver affect blood flow, MR perfusion can improve the sensitivity and specificity of diagnostic liver imaging, providing information concerning the intratumoral distribution of vessels (vascular density) as well as the nature of the vascular wall (intact or immature and leaky blood vessels) [6,18]. This shows potential for better understanding of tumor enhancement patterns and angiogenesis; therefore, MR perfusion can be utilized for the detection and characterization of focal liver lesions and the quantification of blood flow parameters [6,[19][20][21].…”

“…This shows potential for better understanding of tumor enhancement patterns and angiogenesis; therefore, MR perfusion can be utilized for the detection and characterization of focal liver lesions and the quantification of blood flow parameters [6,[19][20][21]. Recently, Wang et al [6] reported that the TSIC for FNH showed signs of "arterialization" (steep enhancement) in the first part of the curve and subsequently signs of "hepatization" (curve running slightly above but parallel to the curve of the liver), in according to our results. In fact, in our study, all FNHs presented a curve of Type 1, showing quick and marked enhancement and quick decay followed by slowly decaying, related to the predominant arterial support, with mean TTP=20.333, mean ME%= 290.952 and mean MS=31.142.…”

Prostate cancer - the role of magnetic resonance imaging

“…ADC derived from DWI, demonstrates reduced ADC values and increased fractional anisotropy (FA) in prostate cancer. DCE-MRI visualises tumor perfusion and capillary wall permeability and hydrostatic pressure 6 .…”

Incremental value of magnetic resonance imaging in the advanced management of prostate cancer

“…DWI demonstrated reduced ADC values and increased fractional anisotropy in prostate cancer. DCE-MRI has been used to visualize tumor perfusion and tumor capillary wall permeability and hydrostatic pressure [42] . Vascular endothelial growth factor has a role in increasing tumor capillary wall permeability.…”