Lebermetastasendetektion

Chu

2021

CMAR

The incidence and mortality rate of breast cancer (BC) in women currently ranks first worldwide, and neoadjuvant chemotherapy (NAC) is widely used in patients with BC. A variety of imaging assessment methods have been used to predict and evaluate the response to NAC. Ultrasound (US) has many advantages, such as being inexpensive and offering a convenient modality for follow-up detection without radiation emission. Although conventional grayscale US is typically used to predict the response to NAC, this approach is limited in its ability to distinguish viable tumor tissue from fibrotic scar tissue. Contrast-enhanced ultrasound (CEUS) combined with a time-intensity curve (TIC) not only provides information on blood perfusion but also reveals a variety of quantitative parameters; elastography has the potential capacity to predict NAC efficiency by evaluating tissue stiffness. Both CEUS and elastography can greatly improve the accuracy of predicting NAC responses. Other US techniques, including three-dimensional (3D) techniques, quantitative ultrasound (QUS) and US-guided near-infrared (NIR) diffuse optical tomography (DOT) systems, also have advantages in assessing NAC response. This paper reviews the different US technologies used for predicting NAC response in BC patients based on the previous literature.

Section: Contrast-enhanced Ultrasound (Ceus) For Assessing Response To Nacmentioning

confidence: 99%

A Narrative Review of Ultrasound Technologies for the Prediction of Neoadjuvant Chemotherapy Response in Breast Cancer

Chu

2021

CMAR

“…Even if the vascular pattern of enhancement is described with the same criteria as in contrast-enhanced CT (CECT) and contrast-enhanced MRI (CEMRI), the examinations are not equivalent due to the different pharmacokinetics of UCAs. In contrast to cross-sectional CAs, which are rapidly cleared from the blood pool into the extracellular space, UCAs are strictly intravascular and do not diffuse into the tumor interstitium [ 1 , 6 , 11 , 12 , 13 , 14 , 15 , 16 ], allowing for a better characterization of focal liver lesions (FLLs) [ 17 ]. Several enhancement patterns can be identified for FLLs after UCA administration.…”

Section: The Basics Of Ucasmentioning

confidence: 99%

“…Due to their physical size, UCAs are true blood pool agents and do not diffuse outside the capillaries or other vessels, unless there is an ongoing hemorrhage. Being strictly intravascular, UCAs allow a better characterization of FLLs, especially during portal and late venous phases, and a more confident evaluation of washout phenomena compared to CT or MRI CAs, which are rapidly cleared from the blood pool into the extracellular space and may conceal washout [ 1 , 2 , 3 , 6 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 47 , 48 ].…”

Section: Advantages Of Ucasmentioning

confidence: 99%

Advantages and Limitations of Focal Liver Lesion Assessment with Ultrasound Contrast Agents: Comments on the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) Guidelines

Chiorean

Tana²,

Braden³

et al. 2016

Med Princ Pract

Contrast-enhanced ultrasound (CEUS) represents a significant breakthrough in sonography. Due to US contrast agents (UCAs) and contrast-specific techniques, sonography offers the potential to show enhancement of liver lesions in a similar way as contrast-enhanced cross-sectional imaging techniques. The real-time assessment of liver perfusion throughout the vascular phases, without any risk of nephrotoxicity, represents one of the major advantages that this technique offers. CEUS has led to a dramatic improvement in the diagnostic accuracy of US and subsequently has been included in current guidelines as an important step in the diagnostic workup of focal liver lesions (FLLs), resulting in a better patient management and cost-effective therapy. The purpose of this review was to provide a detailed description of contrast agents used in different cross-sectional imaging procedures for the study of FLLs, focusing on characteristics, indications and advantages of UCAs in clinical practice.

“…The ultrasound contrast agent consists of gas-filled microbubbles stabilized by a supporting shell of biocompatible material like protein, lipid or polymer [ 9 – 11 ]. First-generation agents were filled with room air, which had the disadvantage to diffuse quickly into surrounding plasma.…”

Section: Introductionmentioning

confidence: 99%

When is contrast-enhanced sonography preferable over conventional ultrasound combined with Doppler imaging in renal transplantation?

et al. 2015

Conventional ultrasound in combination with colour Doppler imaging is still the standard diagnostic procedure for patients after renal transplantation. However, while conventional ultrasound in combination with Doppler imaging can diagnose renal artery stenosis and vein thrombosis, it is not possible to display subtle microvascular tissue perfusion, which is crucial for the evaluation of acute and chronic allograft dysfunctions. In contrast, real-time contrast-enhanced sonography (CES) uses gas-filled microbubbles not only to visualize but also to quantify renal blood flow and perfusion even in the small renal arterioles and capillaries. It is an easy to perform and non-invasive imaging technique that augments diagnostic capabilities in patients after renal transplantation. Specifically in the postoperative setting, CES has been shown to be superior to conventional ultrasound in combination with Doppler imaging in uncovering even subtle microvascular disturbances in the allograft perfusion. In addition, quantitative perfusion parameters derived from CES show predictive capability regarding long-term kidney function.