Intra-individual comparison of image contrast in SPIO-enhanced liver MRI at 1.5T and 3.0T

Abstract

The purpose of the study was to examine if the higher susceptibility at 3.0 Tesla (T) compared to 1.5 T will affect the contrast in MR imaging of the liver after application of superparamagnetic iron oxide particles (SPIO). The study was approved by our institutional review board and informed consent was obtained. Seventeen healthy volunteers were examined in a prospective, intra-individual comparative study within one day on a 1.5 T and a 3.0 T MRI system. T2 weighted TSE sequences were acquired after bolus injection of a SPIO contrast agent. Image contrast and signal to noise ratio (SNR) were compared between the field strengths. Image contrast was calculated between the liver tissue and the kidneys / spleen / muscles and fluids. The students'T-test was used for statistical analysis. No influence of the higher field strength could be observed on image contrast except for the liver / muscle contrast. This was due to a distinct SNR increase of the muscle tissue at 3.0 T as a result of their relaxation properties. The higher susceptibility at 3.0 T compared to 1.5 T does not translate into a stronger signal attenuation of the SPIO enhanced liver parenchyma.

Cerebral blood flow and metabolism associated with cerebral microbleeds in small vessel disease

“…Increased magnetic field strength seems to improve CMB conspicuity [28,29]. However, stronger magnetic fields are also reported to cause stronger magnetic susceptibility artifacts [30], and the implication of CMBs Data are mean ± standard deviation CBF cerebral blood flow, CBV cerebral blood volume, OEF oxygen extraction fraction, CMRO 2 cerebral metabolic rate of oxygen Data are mean ± standard deviation. P value by the Mann-Whitney U test CBF cerebral blood flow, CBV cerebral blood volume, OEF oxygen extraction fraction, CMRO 2 cerebral metabolic rate of oxygen detected by increased magnetic field strength has not been fully clarified.…”

Comparison of lymph node metastases assessment With the use of USPIO‐enhanced MR imaging at 1.5 T versus 3.0 T in a rabbit model

“…The question whether the magnetic field strength affect the contrast in MRI enhanced by iron particles has been put forward (19,20). The T2* effect is affected by the magnetic field strength, and according to the report by Simon et al (21), the T2 relaxivity of USPIO has been demonstrated to be stronger at 3.0 T as compared to 1.5 T. Therefore, a different SI change of USPIO-enhanced MRI between 1.5 T and 3.0 T could be expected, which might result in a different diagnostic accuracy of lymph node metastasis detection.…”

Detection of hepatic metastases by superparamagnetic iron oxide-enhanced MR imaging: prospective comparison between 1.5-T and 3.0-T images in the same patients

“…The signal decrease of the liver parenchyma because of the susceptibility effect on T2*-weighted gradient-recalled-echo (GRE) and T2-weighted fast spin-echo (FSE) sequences provides increased sensitivity for detection of focal hepatic lesions as a result of a contrast improvement in non-cirrhotic liver [16,17]. Some studies have shown increased accuracy of detecting hepatic metastases by SPIO-enhanced MR imaging at 1.5 T [18][19][20], and some investigators have suggested that field strength affected the signal in SPIO-enhanced MR imaging [21][22][23] in a way that should make SPIO-enhanced MR imaging at 3.0 T superior to imaging at 1.5 T. To our knowledge, however, only one study has compared the diagnostic performance of SPIO-enhanced MR imaging at 3.0 T and 1.5 T in relation to detection of hepatic malignancies [24], and no studies have compared the efficacy of SPIOenhanced MR imaging at 3.0 T and at 1.5 T for detection of hepatic metastases.…”