Flow Artifacts Research Articles

Radial Scan法のフローアーチファクト抑制効果について

Radial scan method collects blades rotated about the k-space origin. The one blade is the group of the echo acquired each repetition time (TR) in concentric strips. Because each of the blades has the phase-encode direction, it can be expected to be dispersing flow artifact which appear in the phase-encode direction. We examined how to produce flow artifact in radial scan method without motion correction. Flow artifact does not appear like a mass in radial scan method. Background noise in radial scan method tended to decrease when width of the blade is thinner and a number of blades is larger under a number of echo is keeping. In conclusion, unlike past countermeasures against flow artifact in Cartesian method, flow artifact becomes inconspicuous to be dispersed by 360 degrees in radial scan method.

Chronic imaging of cortical sensory map dynamics using a genetically encoded calcium indicator

In vivo optical imaging can reveal the dynamics of large-scale cortical activity, but methods for chronic recording are limited. Here we present a technique for long-term investigation of cortical map dynamics using wide-field ratiometric fluorescence imaging of the genetically encoded calcium indicator (GECI) Yellow Cameleon 3.60. We find that wide-field GECI signals report sensory-evoked activity in anaesthetized mouse somatosensory cortex with high sensitivity and spatiotemporal precision, and furthermore, can be measured repeatedly in separate imaging sessions over multiple weeks. This method opens new possibilities for the longitudinal study of stability and plasticity of cortical sensory representations.

Three-dimensional isotropic T2-weighted cervical MRI at 3 T: Comparison with two-dimensional T2-weighted sequences

To compare three-dimensional (3D) isotropic T2-weighted magnetic resonance imaging (MRI) sequences and reformation with two-dimensional (2D) T2-weighted sequences regarding image quality of the cervical spine at 3T. A phantom study was performed using a water-filled cylinder. The signal-to-noise and image homogeneity were evaluated. Fourteen (n=14) volunteers were examined at 3T using 3D isotropic T2-weighted sagittal and conventional 2D T2-weighted sagittal, axial, and oblique sagittal MRI. Multiplanar reformation (MPR) of the 3D T2-weighted sagittal dataset was performed simultaneously with image evaluation. In addition to artefact assessment, the visibility of anatomical structures in the 3D and 2D sequences was qualitatively assessed by two radiologists independently. Cohen's kappa and Wilcoxon signed rank test were used for the statistical analysis. The 3D isotropic T2-weighted sequence resulted in the highest signal-to-noise ratio (SNR) and lowest non-uniformity (NU) among the sequences in the phantom study. Quantitative evaluation revealed lower NU values of the cerebrospinal fluid (CSF) and muscles in 2D T2-weighted sagittal sequences compared to the 3D volume isotropic turbo spin-echo acquisition (VISTA) sequence. The other NU values revealed no statistically significant difference between the 2D turbo spin-echo (TSE) and 3D VISTA sequences (0.059<p<0.959). 3D VISTA images showed significantly fewer CSF flow artefacts (p<0.001) and better delineated intradural nerve rootlets (p=0.001) and neural foramina (p=0.016) compared to 2D sequences. A 3D T2 weighted sequence is superior to conventional 2D sequences for the delineation of intradural nerve rootlets and neural foramina and is less affected by CSF flow artefacts.

Black blood MRI has diagnostic and prognostic value in the assessment of patients with pulmonary hypertension

Double inversion recovery (DIR) "black blood" MRI suppresses the signal from flowing blood, slow flowing blood causes incomplete suppression resulting in pulmonary blood flow artefact (PFA). This study examines the diagnostic utility and prognostic value of a PFA scoring system in a mixed cohort of patients with pulmonary hypertension (PH). DIR-MRI images were reviewed for 233 patients referred with suspected PH who underwent right heart catheterisation (RHC) within 48 h of MR. The degree of PFA was visually scored in all patients from 0 to 5 (0 = absent, 1 = segmental, 2 = lobar, 3 = distal main, 4 = proximal main and 5 = trunk). Pulmonary artery (PA), aorta (Ao), and PA main branch diameters were measured from which PA/Ao ratios and mean PA branch diameters (MPAB) were calculated. PFA >1 demonstrated high sensitivity (86%) and specificity (85%) for the diagnosis PH in our mixed patient cohort. A good correlation was found with PFA and haemodynamic parameters, PVR (r = 0.70), mPAP (r = 0.65) and CI (r = -0.53). PFA predicted mortality (P = 0.005) during the mean follow-up for 19 months. PFA scoring demonstrated good inter-observer agreement (k = 0.83). PFA scoring is of diagnostic and prognostic value in the assessment of patients with suspected PH. and is a predictor of mortality. • A simple magnetic resonance method of assessing pulmonary blood flow is presented • This involves a qualitative scoring system of black blood pulmonary flow artefacts • This is simple to perform and seems reproducible in pulmonary hypertension patients • The degree of artefact correlates well with right heart catheter measurements • Prominent pulmonary flow artefact predicts mortality in patients with pulmonary hypertension.

3D Fluid-Attenuated Inversion Recovery Imaging: Reduced CSF Artifacts and Enhanced Sensitivity and Specificity for Subarachnoid Hemorrhage

FLAIR images are highly sensitive for SAH. However, CSF flow artifacts caused by conventional FLAIR can produce false-positive results. Here, we compare 3D and 3D FLAIR sequences, focusing on their potential for containing these artifacts and their sensitivity and specificity for detection of SAHs. We evaluated the following 4 FLAIR sequences: 1) 2D FLAIR at 1.5T, 2) 2D FLAIR, 3) 2D PROPELLER-FLAIR, and 4) 3D Cube-FLAIR at 3T. All sequences were performed in 5 healthy volunteers; sequences 2 and 4 were also performed under routine conditions in 10 patients with focal epilepsy and in 10 patients with SAH. Two neuroradiologists independently conducted the analysis. The presence of flow artifacts in the ventricles and cisterns of healthy volunteers and patients with epilepsy was evaluated and scored on a 4-point scale. Mean values were calculated and compared by using paired t tests. Sensitivity and specificity for SAH detection in sequences 2 and 4 were determined. Cube-FLAIR showed almost no CSF artifacts in the volunteers and the patients with epilepsy; therefore, it was superior to any other FLAIR (P < .001). Sensitivity and specificity of SAH detection by 3T FLAIR were 58.3% and 89.4%, respectively, whereas Cube-FLAIR had a sensitivity of 95% and a specificity of 100%. Cube-FLAIR allows FLAIR imaging with almost no CSF artifacts and is, thus, particularly useful for SAH detection.

Reduction of the skin blood flow artifact from near-infrared spectroscopy signals

Reduction of the skin blood flow artifact from near-infrared spectroscopy signals

Estimation de la distensibilité aortique à partir de séquences d’images de résonance magnétique « steady-state free-precession » et « contraste de phase »

Objective To investigate the accuracy in the estimation of the aortic lumen area and distensibility obtained from Steady-State Free-Precession (SSFP) and Phase Contrast (PC) MR sequences. Subjects and methods Systolic and diastolic aortic lumen of the ascending and descending aorta of 50 subjects, collected with both acquisition sequences, were extracted using a 2D + t automated segmentation method. Results While the statistical study indicated very similar lumen areas for SSFP and PC data (slope = 1, r = 0.99), the corresponding distensibility values were less correlated ( r = 0.54). Comparison between distensibility values in the ascending and descending aorta and study of these values with aging indicated a greater coherence with expected physiological behavior of the aorta when using SSFP images. Discussion Flow artifacts were more severe in PC images and could explain the better results obtained when using SSFP sequences. Conclusion A more accurate local assessment of the aortic stiffness is obtained from SSFP image sequences than from PC image sequences.

Time resolved velocity measurements of unsteady systems using spiral imaging

Spiral imaging has been assessed as a tool for the measurement of spatially and temporally resolved velocity information for unsteady flow systems. Using experiments and simulated acquisitions, we have quantified the flow artefacts associated with spiral imaging. In particular, we found that despite the adverse effect of in-plane flow on the point spread function, for many physical systems the extent of blurring associated with spiral imaging is marginal because flows represented by high spatial Fourier coefficients, which would be those most affected by the distortion of the point spread function, exist at the physical boundaries of the flow and are therefore associated with much smaller velocities than are characteristic of the bulk flow. The necessity for a flow imaging technique which is robust to the accrual of velocity proportionate phase during imaging was demonstrated in an experimental comparison of spiral imaging and echo-planar imaging (EPI) applied to turbulent flow in a pipe. While the measurements acquired using EPI accrued substantial velocity proportionate phase, those acquired using spiral imaging were not significantly affected. High temporal velocity measurements using spiral imaging were demonstrated on turbulent flow in a pipe (image acquisition time 5.4 ms; 91 frames per second), which enabled the transient behaviour of wall instabilities to be captured. Additionally, the technique was applied to a multiphase flow system, where the wakes behind single rising bubbles were characterised. Spiral imaging thus seems an auspicious basis for the measurement of velocity fields for unsteady flow systems.

Reduction of flow artifacts by using partial saturation in RF-spoiled gradient-echo imaging

Radiofrequency (RF)-spoiled gradient-echo imaging provides a signal intensity close to pure T(1) contrast by using spoiler gradients and RF phase cycling to eliminate net transverse magnetization. Generally, spins require many RF excitations to reach a steady-state magnetization level; therefore, when unsaturated flowing spins enter the imaging slab, they can cause undesirable signal enhancement and generate image artifacts. These artifacts can be reduced by partially saturating an outer slab upstream to drive the longitudinal magnetization close to the steady state, while the partially saturated spins generate no signal until they enter the imaging slab. In this work, magnetization evolution of flowing spins in RF-spoiled gradient-echo sequences with and without partial saturation was simulated using the Bloch equations. Next, the simulations were validated by phantom and in vivo experiments. For phantom experiments, a pulsatile flow phantom was used to test partial saturation for a range of flip angles and relaxation times. For in vivo experiments, the technique was used to image the carotid arteries, abdominal aorta, and femoral arteries of normal volunteers. All experiments demonstrated that partial saturation can provide consistent T(1) contrast across the slab while reducing inflow artifacts.

A fully-automated statistical method for characterization of flow artifact presence in cardiac MRI

Flow artifacts in MR images can appear as ghosts within and outside the body cavity. Current approaches for optimizing sequences for suppressing such artifacts rely on expert scoring or on semi-automated methods for evaluation.

Adiabatic T2-preparation modules optimized for robustness toward cardiac motion and flow - a comparison with existing techniques at 3 Tesla

Background T2-imaging of the heart at 3 Tesla demands T2-preparations not only insensitive to B0 and B1, but also toward cardiac motion and flow in order to avoid flow artifacts and concomitant myocardial contamination and to preserve endocardial border definition. While more refocusing pulses per T2-prep duration improve robustness, they also increase SAR. We chose four BIREF-1 refocusing pulses (one adiabatic fast passage per pulse) to achieve motion-robustness while requiring lower energy than an equal number of pairs of adiabatic fast-passage. We compared two new techniques (NTs) using described scheme to MLEV4 [1] and adiabatic [2] schemes.

Fast spin‐echo triple echo dixon: Initial clinical experience with a novel pulse sequence for simultaneous fat‐suppressed and nonfat‐suppressed T2‐weighted spine magnetic resonance imaging

To evaluate a prototype fast spin-echo (FSE) triple-echo Dixon (FTED) technique for T2-weighted spine imaging with and without fat suppression compared to conventional T2-weighted fast recovery (FR) FSE and short-tau inversion recovery (STIR) imaging. Sixty-one patients were referred for spine magnetic resonance imaging (MRI) including sagittal FTED (time 2:26), STIR (time 2:42), and T2 FRFSE (time 2:55). Two observers compared STIR and FTED water images and T2 FRFSE and FTED T2 images for overall image quality, fat suppression, anatomic sharpness, motion, cerebrospinal fluid (CSF) flow artifact, susceptibility, and disease depiction. On FTED images water and fat separation was perfect in 58 (.95) patients. Compared to STIR, the FTED water images demonstrated less motion in 57 (.93) of 61 patients (P < 0.05), better anatomic sharpness in 51 (.84) and patients (P < 0.05), and less CSF flow artifact in 7 (.11) P < 0.05) patients. There was no difference in fat suppression or chemical shift artifact. T2 FRFSE and FTED T2 images showed equivalent motion, CSF flow, and chemical shift artifact. Lesion depiction was equivalent on FTED water and STIR images and FTED T2 and T2 FRFSE images. FTED efficiently provides both fat-suppressed and nonfat-suppressed T2-weighted spine images with excellent image quality, equal disease depiction, and 56% reduction in scan time compared to conventional STIR and T2 FRFSE.

Nonenhanced methods for lower‐extremity MRA: A phantom study examining the effects of stenosis and pathologic flow waveforms at 1.5T

To evaluate the signal properties of 2D time of flight (TOF), quiescent-interval single-shot (QISS), ECG-gated 3D fast spin-echo (FBI), and ungated 3D fast spin-echo ghost (Ghost) magnetic resonance angiography (MRA) over a range of flow velocities in a pulsatile flow phantom with a 50% diameter stenosis at 1.5T. Blood-mimicking fluid was pumped at eight peak flow velocities through a stenotic region in triphasic and monophasic waveforms. Vascular signal proximal, within, and distal to the stenosis was measured from the source images of the four MRA methods. Coronal maximum intensity projection images were used to compare image quality. TOF and QISS signal trends were similar, but QISS exhibited the most consistent signal across velocities. At high velocities (≥ 42.4 cm/s), TOF showed poststenotic signal loss that was not observed with QISS. FBI and Ghost signals peaked at low velocities (3.9-9.7 cm/s) without flow compensation and at high velocities (≥ 64.6 cm/s) with flow compensation. FBI and Ghost demonstrated dependence on blood flow velocity and flow compensation. TOF was sensitive to flow artifacts at high velocities. QISS proved most robust for accurately depicting the normal lumen and stenosis under a wide range of flow conditions. Monophasic and triphasic flow did not appreciably affect the signal performance of any method.

The magnetization transfer effect in brain studies by 1.5 T magnetic resonance system. When the radiographer should apply it?

Purpose The Magnetization Transfer (MT) obtained by applying a pre-saturation pulse is, in Magnetic Resonance Imaging (MRI), a technique that allows for additional enhancement of lesions on conventional T1 images after contrast administration. This study aims to assess the effectiveness of the technique measuring how MT could improve image quality and diagnostic values through the enhancement of lesions. Methods Thirteen T1-weighted spin-echo (SE) sequences, obtained by the 1.5 T system after contrast media injection, were analyzed with and without MT. The contrast-to-noise ratio (CNR), as well as the signal-to-noise ratio (SNR) variables were compared in all sequences, according to the reference structures: lateral ventricles, white matter, gray matter, caudate nucleus and internal capsule. The MT ratio average was calculated using the ANOVA scale in order to assess the CNR and the magnetization transfer effect (MTE) for the different lesions and for both sequences (with and without MT). For the assessment of the flow artifact, clinical experts applied a Likert scale with 5 points. Results For CNR values, the differences between conventional and MT-pulsed images were significant ( Student t testp < 0,05), remaining significant for SNR in all structures except for the lateral ventricles. For the flow artifacts the differences found by the coefficient Kappa agreement were not significant as the differences found for the CNR and the MTE between the two sequences ( p > 0,05). Conclusion In identical conditions of acquisition, the MT does not produce significant differences in the enhancement of lesions, however, it allows a greater capacity to detect the multiple sclerosis plaques, comparing structures around basal nucleus versus gray and white matter.

Duplex and contrast enhanced ultrasound (CEUS) in evaluation of in-stent restenosis after carotid stenting

The aim of the study was to evaluate whether contrast enhanced ultrasound (CEUS) can improve the visualization of in-stent restenosis after carotid stenting of the internal carotid artery (ICA) in comparison to color-coded duplex sonography (CCDS) and power Doppler. The study included the follow up of thirty patients after carotid artery stenting (CAS). Intrastenotic flow detection and lengths of in-stent restenosis were the main criteria. A high-end ultrasound machine (Siemens, ACUSON, Sequoia or S2000) with a multi-frequency linear 9 MHz or 15 MHz transducer was used to carry out contrast-enhanced ultrasound with SonoVue. In cases of treatment of a high degree in-stent stenosis intra-arterial digital subtraction angiography (DSA) was used. All patients were examined using all diagnostic ultrasound tools of the study. In five patients (17%) an in-stent restenosis of the internal carotid artery (ICA) was found. Two patients need a reintervention. The results show that the contrast enhanced ultrasound could improve the diagnostic assessment capabilities in comparison to CCDS and power Doppler for patients with in-stent restenosis after carotid stenting of the ICA. Contrast enhanced ultrasound is a reliable method for the evaluation of in-stent restenosis after carotid stenting of the ICA. CEUS provides a reduction in intrastenotic flow artefacts, resulting in better visualisation and detection of the complete length of the stenosis in comparison with CCDS and power Doppler. In order to elucidate hemodynamic changes, additional Doppler examinations are still necessary.

Is there a role for BLADE acquisition in T2-weighted breast MRI?

standard T2-weighted (T2W) magnetic resonance imaging (MRI) is a necessary component of routine breast MRI. However, breast MRI suffers from minor subject movements, which degrade the image quality. BLADE acquisition MRI is a promising motion degradation method currently used in brain imaging. to compare T2W BLADE acquisition breast MR images with routine T2W images in the evaluation of motion artifacts and overall image quality. MRI was performed with a 1.5 T system on 25 volunteers and 25 consecutive patients with identical imaging parameters for both MRI sequences (TR 5240 ms, TE 112-108 ms, acquisition 1, spatial resolution 0.9×0.9× 4 mm). Motion and flow artifacts and pectoral muscle and lesion contour delineations were assessed. Signal to noise ratios (SNRs) of images and contrast to noise ratios (CNRs) of the incidental lesions were calculated. The results were evaluated with the Wilcoxon signed-ranks test. of the 50 patients, 44 were included in the analysis (mean age 42.1 years). Motion artifacts were prominent in 48% cases on routine T2W and in only 2% of BLADE cases. The SNR values of BLADE images were significantly higher than routine T2W (P<0.05). Pectoral muscle contours were better assessed on BLADE in all cases. Sequence performances were similar in flow artifacts, CNR values, and contour delineation of incidental lesions. The readers chose BLADE sequence MRI in 25 cases and found the overall performance of sequences equal in 19 cases. None of the readers preferred routine T2W to BLADE. the performance of BLADE is superior to routine T2W images in eliminating motion artifacts, provides better SNRs, shows detailed pectoral muscle contours, and may be the sequence of choice.

Magnetic resonance cholangiopancreatography in conjunction with 3D for assessment of different biliary obstruction causes

ObjectiveTo assess the diagnostic value of magnetic resonance imaging in conjunction with 3D-MRCP, with maximum intensity projections and volume rendered images in different biliary obstruction causes. Patient and methodsThis study retrospectively reviewed the radiology records of 29 patients (18 females and 11 males) suffering from obstructive jaundice. All patients were subjected to magnetic resonance imaging (MRI), 3D-MRCP with maximum intensity projection (MIP) and volume rendered (VR) reformatted images for biliary obstruction diseases in Zagazig University Hospitals between November 2008 and January 2010. MR studies were performed with 1.5-T superconductive magnet (Philips Achieva, class II a). The patient ages were ranging from 23 to 66years (mean age: 34years). This study was done to evaluate the diagnostic value and accuracy of the new MRI techniques as a non-invasive tool to diagnose and differentiate between benign and malignant variants of biliary obstruction diseases and to facilitate the management planning. All cases were evaluated by clinical examination, laboratory values, grey and colored scale ultrasonography, conventional MRI, three-dimensional (3D-MRCP), MIP, and VR images. Our results were correlated with the histology of the resected specimen, operative (ERCP) or image-guided biopsy in inoperable patients. ResultsThe mean age of benign patients was 30years compared with 54years in malignant biliary obstruction. Seventeen patients had benign cases 58.6% (6 cases of benign stricture and 11 cases with choledocholithiasis). The other 12 cases had malignant aetiology. Twenty-three patients were subjected to operative procedures, while the remaining six had ERCP/PTC and stenting. The MRI/MRCP images were of good quality in all patients. The intra- and extra-hepatic biliary radicals were visualized completely including the proximal and distal extent of the stricture. Regarding the benign cases (16/17) were satisfactorily diagnosed, however, one case was false negative, due to missed small stone at the MIP reconstructions. The 12 malignant biliary obstruction cases were as follows: five cases were cholangiocarcinoma (one peripheral type, one perihilar position, one Klatskin’s type, and two cases of the distal type), three pancreatic neoplastic lesions, two ampullary carcinoma, and two malignant lymph nodes. Regarding the benign cases 3D-MRCP had 94.1% diagnostic accuracy, otherwise more accuracy reported in malignant causes 100%. Conclusion3D-MRCP with MIP creates global images for pancreatico-biliary system. It is as effective as ERCP in detection of biliary obstruction and can precisely determine its level as well. Furthermore, it can provide a road map for management planning. By avoiding the flow artifacts, the false negative results that previously reported in past studies can be reduced.

Investigating the effects of intensity threshold on high-frequency three-dimensional power Doppler ultrasound.

High-frequency power Doppler ultrasound is a non-invasive vascular imaging modality ideal for a quantitative assessment of vascularity in preclinical models. Although it permits detecting slower blood flows than other ultrasound Doppler methods, it is limited by flow artifacts, complicating the interpretation of tumor vascularity metrics such as the vascularity index (VI). Our aim was to examine how parameters such as the intensity threshold affect the VI in in vivo xenograft models. Breast MDA-MB-231 tumors in the hind leg of SCID mice were treated with 0 or 8 Gy radiation, and imaged before and 24 h after treatment. A Vevo770 was used along with a 25-MHz center frequency transducer to obtain 3-D power Doppler images of tumors. Mice were again imaged while in the same position 1 min after sacrifice at 24 h. This was carried out for direct comparison of true blood flow signal to system noise level. The VI was computed for a range of intensity thresholds. The VI-threshold curves varied differently as a function of treatment, and preliminary data indicate an optimal plateau where the intensity threshold should be set, yielding a nearly true blood flow signal and minimizing noise signal. [Work funded by the Canadian Breast Cancer Foundation.]

Fast, reproducible measurement of the vascular input function in mice using constrained reconstruction and cardiac sampling

Dynamic contrast-enhanced MRI is often used to assess the response to therapy in small animal models of cancer. Rigorous quantification of dynamic contrast-enhanced MRI data using common pharmacokinetic models requires dynamic determination of the concentration of contrast in tumor tissue and in blood. Measurement of the blood concentration, or vascular input function (VIF), requires high temporal resolution and is prone to distortion as a result of flow and partial volume artifacts when measured in local blood vessels. We have developed a strategy for the robust measurement of VIF in mice that uses a constrained reconstruction algorithm to enable sampling from the left ventricle of the heart. The feasibility of the algorithm and its resistance to cardiac motion are demonstrated in vivo and through numerical simulations. VIF sampling is interleaved with slices dedicated to tumor coverage to yield a fast VIF sampling period (81 ms) that is decoupled from the temporal resolution of tumor data (3.9 s). The algorithm provides results that agree with fully encoded measurements in the slowly varying component of VIF to within a 4% root-mean-square signal difference. Analysis of a parametric representation of VIFs measured in a population of mice showed a significant reduction in variations observed within subjects (5%-58% over four parameters; p < 0.05) and a reduction in variations between subjects (19%-62%) when using this technique. Preliminary dynamic measurements in an orthotopic xenograft model of anaplastic thyroid cancer revealed a decrease in the variation of pharmacokinetic parameters between mice by a factor of two.

Comparison of multi-echo and single-echo gradient-recalled echo sequences for SPIO-enhanced Liver MRI at 3 T

To assess the utility of a T2*-weighted, multi-echo data imaging combination sequenced on superparamagnetic iron oxide (SPIO)-enhanced liver magnetic resonance imaging (MRI) using a 3 T system. Fifty patients underwent SPIO-enhanced MRI at 3 T using T2*-weighted, single-echo, gradient-recalled echo (GRE) sequences [fast imaging with steady precession; repetition time (TR)/echo time (TE), 126 ms/9 ms; flip angle, 30°] and multi-echo GRE (multi-echo data image combination) sequences (TR/TE, 186 ms/9 ms; flip angle, 30°). Three radiologists independently reviewed the images in a random order. The sensitivity and accuracy for the detection of focal hepatic lesions (a total of 76 lesions in 33 patients; 48 solid lesions, 28 non-solid lesions) were compared by analysing the area under the receiver operating characteristic curves. Image artefacts (flow artefacts, susceptibility artefacts, dielectric artefacts, and motion artefacts), lesion conspicuity, and overall image quality were evaluated according to a four-point scale: 1, poor; 2, fair; 3, good; 4, excellent. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the lesions were compared. Image artefacts were more frequent with single-echo GRE (p<0.05). The mean scale of image quality assessment for flow, susceptibility, dielectric, and motion artefacts were 2.76, 3.13, 3.42, and 2.89 with single-echo, respectively, compared with 3.47, 3.43, 3.47, and 3.39, respectively, with multi-echo GRE. There was no significant difference in lesion conspicuity between single-echo (3.15) and multi-echo (3.30) GRE sequences. The overall image quality was significantly (p<0.05) better with multi-echo (3.37) than with single-echo GRE (2.89). The mean SNR and CNR of the lesions were significantly (p<0.05) higher on multi-echo (79±23 and 128±59, respectively) images than on single-echo (38±11 and 102±44, respectively) images. Lesion detection accuracy and sensitivity were not significantly different between the two sequences. Mean accuracies and sensitivities were 0.864 and 0.785 for single-echo and 0.847 and 0.785 for multi-echo GRE, respectively. At 3 T, the T2*-weighted, multi-echo data image combination sequence performs comparably to the T2*-weighted, single-echo GRE sequence for SPIO-enhanced MRI with good overall image quality and a decrease in undesired artefacts.