Free-breathing contrast-enhanced multiphase MRI of the liver in patients with a high risk of breath-holding failure: comparison of compressed sensing-accelerated radial and Cartesian acquisition techniques

2021 ◽  
pp. 028418512110529
Author(s):  
Eun Sun Choi ◽  
Jin Sil Kim ◽  
Marcel Dominik Nickel ◽  
Jae Kon Sung ◽  
Jeong Kyong Lee
Keyword(s):  
Image Quality ◽  
Detection Rate ◽  
Free Breathing ◽  
Arterial Phase ◽  
Breath Holding ◽  
Diagnostic Quality ◽  
Contrast Enhanced ◽  
Edge Sharpness ◽  
Liver Edge

Background Knowing the advantages and disadvantages of each magnetic resonance (MR) technique, would allow us to choose a sequence better suited in patients with a high risk of breath-holding failure. Purpose To compare the image quality of free-breathing contrast-enhanced multiphase MR imaging (MRI) using incoherent Cartesian k-space sampling combined with a motion-resolved compressed sensing reconstruction (XD-VIBE) and Golden-Angle Radial Sparse Parallel MRI (GRASP). Material and Methods A total of 67 patients were included. Overall image quality, motion artifacts, and liver edge sharpness on arterial and portal-venous phase were evaluated by two radiologists. We evaluated the signal intensity ratio between liver in the late arterial phase to aorta at peak enhancement and the detection rate of hypervascular lesions. Results Overall image quality, artifact, and liver edge sharpness scores of XD-VIBE and GRASP were not significantly different ( P = 0.070–0.397). Four (reviewer 1, 12.1%) and seven patients (reviewer 2, 21.2%) received non-diagnostic quality in the XD-VIBE group whereas one patient (reviewer 2, 2.9%) received non-diagnostic quality in the GRASP group. The ratio between the aorta and liver signal for GRASP was significantly higher than that of XD-VIBE (0.32 ± 0.10 vs. 0.47 ± 0.13; P < 0.001). The hypervascular lesion detection rate of XD-VIBE (86.7%) was higher than that of GRASP (57.1%) in the arterial phase without a statistically significant difference ( P = 0.081). Conclusion Overall image quality of XD-VIBE and GRASP were not significantly different. More XD-VIBE examinations were rated non-diagnostic. On the other hand, the relative liver parenchymal enhancement to the aorta in the late arterial phase of GRASP was higher than that of XD-VIBE, which potentially leads to lower detectability of hypervascular lesions on arterial phase images.

Free-breathing contrast-enhanced upper abdominal MRI in children: comparison between Cartesian acquisition and stack-of-stars acquisition with two different fat-suppression techniques

2020 ◽  
pp. 028418512092893
Author(s):  
Jeong Rye Kim ◽  
Hee Mang Yoon ◽  
Young Ah Cho ◽  
Jin Seong Lee ◽  
Ah Young Jung
Keyword(s):  
Image Quality ◽  
Free Breathing ◽  
Quality Parameters ◽  
Fat Suppression ◽  
Coefficients Of Variation ◽  
Contrast Enhanced ◽  
Abdominal Mri ◽  
Edge Sharpness ◽  
Upper Abdomen ◽  
Stack Of Stars

Background Respiratory artifacts impair image quality of magnetic resonance imaging (MRI) in children who cannot hold breath during MRI examination. Purpose To compare the quality of free-breathing contrast-enhanced 3D T1-weighted (T1W) images of the upper abdomen in children using Cartesian acquisition (Cartesian eTHRIVE), stack-of-stars acquisition with spectral fat suppression (3D VANE eTHRIVE), and stack-of-stars acquisition with fat suppression using modified Dixon (3D VANE mDixon). Material and Methods Pediatric patients (aged <19 years) who underwent whole-body MRI with free-breathing contrast-enhanced T1W axial scans of upper abdomen using Cartesian eTHRIVE, 3D VANE eTHRIVE, and 3D VANE mDixon were enrolled. Image quality parameters were assessed including overall image quality, hepatic edge sharpness, hepatic vessel clarity, respiratory artifacts, radial artifacts, lesion conspicuity, and lesion edge sharpness using the Likert scale, where a lower score indicated poorer image quality. The coefficients of variation of signal intensity of liver and spleen were analyzed. Results In 41 patients, 3D VANE eTHRIVE showed the highest scores for all image quality parameters ( P ≤ 0.001). 3D VANE eTHRIVE also showed higher scores for respiratory ( P ≤ 0.001) and radial artefacts than 3D VANE mDixon ( P = 0.001). There were no significant differences in coefficients of variation of signal intensity of the liver and spleen between 3D VANE eTHRIVE and 3D VANE mDixon. Acquisition time was longer for 3D VANE eTHRIVE (81.26 ± 16 s) than for Cartesian eTHRIVE (7.87 ± 0.95 s) and 3D VANE mDixon (76.66 ± 12.4 s, P < 0.001). Conclusion The application of stack-of-stars acquisition to 3D T1W abdominal MRI resulted in better image quality than Cartesian acquisition in free-breathing children. In stack-of-stars acquisition, spectral fat suppression resulted in better image quality and fewer artifacts than mDixon.

scholarly journals Radial self-navigated native magnetic resonance angiography in comparison to navigator-gated contrast-enhanced MRA of the entire thoracic aorta in an aortic patient collective

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Martina Correa Londono ◽  
Nino Trussardi ◽  
Verena C. Obmann ◽  
Davide Piccini ◽  
Michael Ith ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Image Quality ◽  
Magnetic Resonance Angiography ◽  
Thoracic Aorta ◽  
Aortic Root ◽  
Aortic Disease ◽  
Ascending Aorta ◽  
Scan Time ◽  
Contrast Enhanced

Abstract Background The native balanced steady state with free precession (bSSFP) magnetic resonance angiography (MRA) technique has been shown to provide high diagnostic image quality for thoracic aortic disease. This study compares a 3D radial respiratory self-navigated native MRA (native-SN-MRA) based on a bSSFP sequence with conventional Cartesian, 3D, contrast-enhanced MRA (CE-MRA) with navigator-gated respiration control for image quality of the entire thoracic aorta. Methods Thirty-one aortic native-SN-MRA were compared retrospectively (63.9 ± 10.3 years) to 61 CE-MRA (63.1 ± 11.7 years) serving as a reference standard. Image quality was evaluated at the aortic root/ascending aorta, aortic arch and descending aorta. Scan time was recorded. In 10 patients with both MRA sequences, aortic pathologies were evaluated and normal and pathologic aortic diameters were measured. The influence of artifacts on image quality was analyzed. Results Compared to the overall image quality of CE-MRA, the overall image quality of native-SN-MRA was superior for all segments analyzed (aortic root/ascending, p < 0.001; arch, p < 0.001, and descending, p = 0.005). Regarding artifacts, the image quality of native-SN-MRA remained superior at the aortic root/ascending aorta and aortic arch before and after correction for confounders of surgical material (i.e., susceptibility-related artifacts) (p = 0.008 both) suggesting a benefit in terms of motion artifacts. Native-SN-MRA showed a trend towards superior intraindividual image quality, but without statistical significance. Intraindividually, the sensitivity and specificity for the detection of aortic disease were 100% for native-SN-MRA. Aortic diameters did not show a significant difference (p = 0.899). The scan time of the native-SN-MRA was significantly reduced, with a mean of 05:56 ± 01:32 min vs. 08:51 ± 02:57 min in the CE-MRA (p < 0.001). Conclusions Superior image quality of the entire thoracic aorta, also regarding artifacts, can be achieved with native-SN-MRA, especially in motion prone segments, in addition to a shorter acquisition time.

scholarly journals Understanding PI-QUAL for prostate MRI quality: a practical primer for radiologists

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Francesco Giganti ◽  
Alex Kirkham ◽  
Veeru Kasivisvanathan ◽  
Marianthi-Vasiliki Papoutsaki ◽  
Shonit Punwani ◽  
...  
Keyword(s):  
Diffusion Weighted Imaging ◽  
Signal To Noise Ratio ◽  
High Signal ◽  
Diagnostic Quality ◽  
Prostate Mri ◽  
Prostate Imaging ◽  
Dynamic Contrast Enhanced ◽  
Diffusion Weighted ◽  
Contrast Enhanced

AbstractProstate magnetic resonance imaging (MRI) of high diagnostic quality is a key determinant for either detection or exclusion of prostate cancer. Adequate high spatial resolution on T2-weighted imaging, good diffusion-weighted imaging and dynamic contrast-enhanced sequences of high signal-to-noise ratio are the prerequisite for a high-quality MRI study of the prostate. The Prostate Imaging Quality (PI-QUAL) score was created to assess the diagnostic quality of a scan against a set of objective criteria as per Prostate Imaging-Reporting and Data System recommendations, together with criteria obtained from the image. The PI-QUAL score is a 1-to-5 scale where a score of 1 indicates that all MR sequences (T2-weighted imaging, diffusion-weighted imaging and dynamic contrast-enhanced sequences) are below the minimum standard of diagnostic quality, a score of 3 means that the scan is of sufficient diagnostic quality, and a score of 5 implies that all three sequences are of optimal diagnostic quality. The purpose of this educational review is to provide a practical guide to assess the quality of prostate MRI using PI-QUAL and to familiarise the radiologist and all those involved in prostate MRI with this scoring system. A variety of images are also presented to demonstrate the difference between suboptimal and good prostate MR scans.

The application of the MPEG-4 standard to telepathology images for electronic patient records

2003 ◽  
Vol 9 (1_suppl) ◽  
pp. 19-21 ◽  
Author(s):  
Georg A Brox ◽  
Janis L Huston
Keyword(s):  
Image Quality ◽  
Patient Records ◽  
Electronic Patient Records ◽  
Diagnostic Image ◽  
Diagnostic Quality ◽  
Compressed Images ◽  
Software Packages ◽  
Mapping Software ◽  
Pixel Mapping

summary We conducted a pilot study to compare the diagnostic quality of digital telepathology images compressed using two software packages, each of which incorporated the MPEG-4 standard. Both software packages produced lossy (rather than lossless) compressed images. Lossy images can be less reliable for diagnostic purposes and the aim of the study was to examine how the MPEG-4 standard affects image quality. The results showed that manipulation of the images by the software did not dramatically alter the image quality but they highlighted the need to develop both pixel-mapping software and associated standards. Standards will help to determine which bits of a diagnostic image can be safely removed during compression while ensuring the integrity and reliability of images for diagnostic purposes.

Evaluation of Shimming Techniques on MRI Breast Image Quality at 1.5T

2019 ◽  
Vol 1 (3) ◽  
pp. 199-204
Author(s):  
Wei Zhou ◽  
Christopher P Favazza ◽  
Jessica A Axmacher ◽  
Joshua D Trzasko ◽  
Jennifer R Geske ◽  
...  
Keyword(s):  
Image Quality ◽  
Statistical Significance ◽  
Breast Mri ◽  
Fat Saturation ◽  
Institutional Review ◽  
Breast Image ◽  
Contrast Enhanced ◽  
Preparatory Phase ◽  
Clinical Mri

Abstract Objective The quality of all clinical MRI is dependent on B0 homogeneity, which is optimized during the shimming part of a prescan or preparatory phase before image acquisition. The purpose of this study was to assess shimming techniques clinically employed for breast MRI across our practice, and to determine factors that correlate with higher image quality for contrast-enhanced breast MRI at 1.5T. Methods One hundred consecutive female patients were retrospectively collected with Institutional Review Board approval. Shimming-related parameters, including shim-box placement and shimming gradient offsets were extracted from prior contrast-enhanced 3D fat-suppressed T1-weighted gradient echo image acquisitions. Three breast radiologists evaluated these images for fat saturation, breast density, overall image quality, and artifacts. Technologist experience was also evaluated for variability of shimming. Generalized linear mixed models were used to compare acquisition parameters between fat saturation. P &lt; 0.05 was considered as statistical significance. Results The percentage of soft tissue inside the field of view (FOV) (ie, Tissue/FOV) in the good fat-saturation group (0.37 ± 0.06) was significantly lower (P &lt; 0.01) than that in the poor fat-saturation group (0.39 ± 0.06). Other shimming-related parameters were found not significantly affecting the fat-saturation outcomes. Technologists with more experience tended to have less variable shimming performance than junior technologists did. Conclusions The quality of clinical MRI and especially breast MRI is highly dependent on shimming. Decreasing Tissue/FOV was associated with good image quality (good fat saturation). Optimization of shimming may require manual shimming or higher-order field-correction strategies.

scholarly journals Non-contrast-enhanced MR portography and hepatic venography with time-spatial labeling inversion pulses: comparison at 1.5 Tesla and 3 Tesla

2015 ◽  
Vol 4 (5) ◽  
pp. 205846011558411 ◽  
Author(s):  
Tsuyoshi Ohno ◽  
Hiroyoshi Isoda ◽  
Akihiro Furuta ◽  
Kaori Togashi
Keyword(s):  
Image Quality ◽  
Portal Vein ◽  
Healthy Volunteers ◽  
Hepatic Vein ◽  
Inversion Recovery ◽  
3 Tesla ◽  
Selective Inversion ◽  
Contrast Enhanced ◽  
Better Than

Background A 3 Tesla (3 T) magnetic resonance (MR) scanner is a promising tool for upper abdominal MR angiography. However, there is no report focused on the image quality of non-contrast-enhanced MR portography and hepatic venography at 3 T. Purpose To compare and evaluate images of non-contrast-enhanced MR portography and hepatic venography with time-spatial labeling inversion pulses (Time-SLIP) at 1.5 Tesla (1.5 T) and 3 T. Material and Methods Twenty-five healthy volunteers were examined using respiratory-triggered three-dimensional balanced steady-state free-precession (bSSFP) with Time-SLIP. For portography, we used one tagging pulse (selective inversion recovery) and one non-selective inversion recovery pulse; for venography, two tagging pulses were used. The relative signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were quantified, and the quality of visualization was evaluated. Results The CNRs of the main portal vein, right portal vein, and left portal vein at 3 T were better than at 1.5 T. The image quality scores for the portal branches of segment 4, 5, and 8 were significantly higher at 3 T than at 1.5 T. The CNR of the right hepatic vein (RHV) at 3 T was significantly lower than at 1.5 T. The image quality scores of RHV and the middle hepatic vein were higher at 1.5 T than at 3 T. For RHV visualization, the difference was statistically significant. Conclusion Non-contrast-enhanced MR portography with Time-SLIP at 3 T significantly improved visualization of the peripheral branch in healthy volunteers compared with1.5 T. Non-contrast-enhanced MR hepatic venography at 1.5 T was better than at 3 T.

scholarly journals Sparse 3D contrast-enhanced whole-heart imaging for coronary artery evaluation

Herz ◽  
2022 ◽  
Author(s):  
Uzair Ansari ◽  
Sonja Janssen ◽  
Stefan Baumann ◽  
Martin Borggrefe ◽  
Stephan Waldeck ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Image Quality ◽  
Cardiac Computed Tomography ◽  
Acquisition Time ◽  
Cohen’S Kappa ◽  
Cohen's Kappa ◽  
Contrast Enhanced ◽  
Significant Difference ◽  
Whole Heart

Abstract Background We investigated the feasibility of evaluating coronary arteries with a contrast-enhanced (CE) self-navigated sparse isotropic 3D whole heart T1-weighted magnetic resonance imaging (MRI) study sequence. Methods A total of 22 consecutive patients underwent coronary angiography and/or cardiac computed tomography (CT) including cardiac MRI. The image quality was evaluated on a 3-point Likert scale. Inter-reader variability for image quality was analyzed with Cohen’s kappa for the main coronary segments (left circumflex [LCX], left anterior descending [LAD], right coronary artery [RCA]) and the left main trunk (LMT). Results Inter-reader agreement for image quality of the coronary tree ranged from substantial to perfect, with a Cohen’s kappa of 0.722 (RCAmid) to 1 (LCXprox). The LMT had the best image quality. Image quality of the proximal vessel segments differed significantly from the mid- and distal segments (RCAprox vs. RCAdist, p < 0.05). The LCX segments showed no significant difference in image quality along the vessel length (LCXprox vs. LCXdist, p = n.s.). The mean acquisition time for the study sequence was 553 s (±46 s). Conclusion Coronary imaging with a sparse 3D whole-heart sequence is feasible in a reasonable amount of time producing good-quality imaging. Image quality was poorer in distal coronary segments and along the entire course of the LCX.

scholarly journals Comparison of Objective Image Quality Metrics to Expert Radiologists’ Scoring of Diagnostic Quality of MR Images

2020 ◽  
Vol 39 (4) ◽  
pp. 1064-1072 ◽  
Author(s):  
Allister Mason ◽  
James Rioux ◽  
Sharon E. Clarke ◽  
Andreu Costa ◽  
Matthias Schmidt ◽  
...  
Keyword(s):  
Image Quality ◽  
Quality Metrics ◽  
Mr Images ◽  
Diagnostic Quality ◽  
Image Quality Metrics
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