Dataset Information

Quantitative evaluation of contrast agent uptake in standard fat-suppressed dynamic contrast-enhanced MRI examinations of the breast.

ABSTRACT: To propose a method to quantify T1 and contrast agent uptake in breast dynamic contrast-enhanced (DCE) examinations undertaken with standard clinical fat-suppressed MRI sequences and to demonstrate the proposed approach by comparing the enhancement characteristics of lobular and ductal carcinomas.A standard fat-suppressed DCE of the breast was performed at 1.5 T (Siemens Aera), followed by the acquisition of a proton density (PD)-weighted sequence, also fat suppressed. Both sequences were characterized with test objects (T1 ranging from 30 ms to 2,400 ms) and calibration curves were obtained to enable T1 calculation. The reproducibility and accuracy of the calibration curves were also investigated. Healthy volunteers and patients were scanned with Ethics Committee approval. The effect of B0 field inhomogeneity was assessed in test objects and healthy volunteers. The T1 of breast tumors was calculated at different time points (pre-, peak-, and post-contrast agent administration) for 20 patients, pre-treatment (10 lobular and 10 ductal carcinomas) and the two cancer types were compared (Wilcoxon rank-sum test).The calibration curves proved to be highly reproducible (coefficient of variation under 10%). T1 measurements were affected by B0 field inhomogeneity, but frequency shifts below 50 Hz introduced only 3% change to fat-suppressed T1 measurements of breast parenchyma in volunteers. The values of T1 measured pre-, peak-, and post-contrast agent administration demonstrated that the dynamic range of the DCE sequence was correct, that is, image intensity is approximately directly proportional to 1/T1 for that range. Significant differences were identified in the width of the distributions of the post-contrast T1 values between lobular and ductal carcinomas (P < 0.05); lobular carcinomas demonstrated a wider range of post-contrast T1 values, potentially related to their infiltrative growth pattern.This work has demonstrated the feasibility of fat-suppressed T1 measurements as a tool for clinical studies. The proposed quantitative approach is practical, enabled the detection of differences between lobular and invasive ductal carcinomas, and further enables the optimization of DCE protocols by tailoring the dynamic range of the sequence to the values of T1 measured.

SUBMITTER: Kousi E

PROVIDER: S-EPMC5814859 | biostudies-other | 2018 Jan

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Quantitative evaluation of contrast agent uptake in standard fat-suppressed dynamic contrast-enhanced MRI examinations of the breast.

Kousi Evanthia E Smith Joely J Ledger Araminta E AE Scurr Erica E Allen Steven S Wilson Robin M RM O'Flynn Elizabeth E Pope Romney J E RJE Leach Martin O MO Schmidt Maria A MA

Medical physics 20171130 1

<h4>Purpose</h4>To propose a method to quantify T<sub>1</sub> and contrast agent uptake in breast dynamic contrast-enhanced (DCE) examinations undertaken with standard clinical fat-suppressed MRI sequences and to demonstrate the proposed approach by comparing the enhancement characteristics of lobular and ductal carcinomas.<h4>Methods</h4>A standard fat-suppressed DCE of the breast was performed at 1.5 T (Siemens Aera), followed by the acquisition of a proton density (PD)-weighted sequence, also ...[more]

PMID: 29095484

Similar Datasets

Project description:To develop a dynamic lesion phantom that is capable of producing physiological kinetic curves representative of those seen in human dynamic contrast-enhanced MRI (DCE-MRI) data. The objective of this phantom is to provide a platform for the quantitative comparison of DCE-MRI protocols to aid in the standardization and optimization of breast DCE-MRI.The dynamic lesion consists of a hollow, plastic mold with inlet and outlet tubes to allow flow of a contrast agent solution through the lesion over time. Border shape of the lesion can be controlled using the lesion mold production method. The configuration of the inlet and outlet tubes was determined using fluid transfer simulations. The total fluid flow rate was determined using x-ray images of the lesion for four different flow rates (0.25, 0.5, 1.0, and 1.5 ml/s) to evaluate the resultant kinetic curve shape and homogeneity of the contrast agent distribution in the dynamic lesion. High spatial and temporal resolution x-ray measurements were used to estimate the true kinetic curve behavior in the dynamic lesion for benign and malignant example curves. DCE-MRI example data were acquired of the dynamic phantom using a clinical protocol.The optimal inlet and outlet tube configuration for the lesion molds was two inlet molds separated by 30° and a single outlet tube directly between the two inlet tubes. X-ray measurements indicated that 1.0 ml/s was an appropriate total fluid flow rate and provided truth for comparison with MRI data of kinetic curves representative of benign and malignant lesions. DCE-MRI data demonstrated the ability of the phantom to produce realistic kinetic curves.The authors have constructed a dynamic lesion phantom, demonstrated its ability to produce physiological kinetic curves, and provided estimations of its true kinetic curve behavior. This lesion phantom provides a tool for the quantitative evaluation of DCE-MRI protocols, which may lead to improved discrimination of breast cancer lesions.

Project description:BACKGROUND:Cerebral blood volume (CBV) mapping with a dynamic susceptibility contrast (DSC) perfusion technique has become a clinical tool in diagnosing and follow-up of brain tumors. Ferumoxytol, a long-circulating iron oxide nanoparticle, has been tested for CBV mapping, but the optimal dose has not been established. PURPOSE:To compare ferumoxytol DSC of two different doses to standard of care gadoteridol by analyzing time-intensity curves and CBV maps in normal-appearing brain regions. STUDY TYPE:Retrospective. SUBJECTS:Fifty-four patients with various brain disorders. FIELD STRENGTH/SEQUENCE:3T MRI. DSC-MRI was performed with 0.1 mmol/kg gadoteridol and 1 day later with ferumoxytol in doses of 1 or 2 mg/kg. ASSESSMENT:Signal changes during first pass, relative CBV (rCBV) in normal-appearing thalamus, putamen, and globus pallidus, and contrast-to-noise ratio (CNR) of the CBV maps were compared between gadoteridol and various doses of ferumoxytol using an automated method. To subjectively assess the quality of the CBV maps, two blinded readers also assessed visual conspicuity of the putamen. STATISTICAL TESTS:Linear mixed effect model was used for statistical comparison. RESULTS:Compared to gadoteridol, 1 mg/kg ferumoxytol showed no difference in CNR (P = 0.6505), peak ?R2*, and rCBV in the putamen (P = 0.2669, 0.0871) or in the thalamus (P = 0.517, 0.9787); 2 mg/kg ferumoxytol increased peak ?R2* as well as the CNR (P < 0.0001), but also mildly increased rCBV in putamen and globus pallidus (P = 0.0005, 0.0012). Signal intensities during first pass remained highly above the noise level, with overlapping of 95% confidence intervals with noise only in 3 out of 162 tested regions. Compared to gadoteridol, the visual image quality showed mild improvement with 1 mg/kg (P = 0.02) and marked improvement with 2 mg/kg ferumoxytol (P < 0.0001). DATA CONCLUSION:1 mg/kg ferumoxytol provides similar imaging results to standard gadoteridol for DSC-MRI, and 2 mg/kg has a benefit of increased CNR, but may also result in mildly increased rCBV values. LEVEL OF EVIDENCE:3 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2018;48:441-448.

Dataset Information

Quantitative evaluation of contrast agent uptake in standard fat-suppressed dynamic contrast-enhanced MRI examinations of the breast.

Publications

Quantitative evaluation of contrast agent uptake in standard fat-suppressed dynamic contrast-enhanced MRI examinations of the breast.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets