Tailored versus fixed scan delay in contrast-enhanced abdominal multi-detector CT: An intra-patient comparison of image quality

Abstract Funding Acknowledgements Type of funding sources: None. Background The natural history of thoracic aortic aneurysm (TAA) is one of progressive expansion. Asymptomatic patients who do not meet criteria for repair require conservative management including ongoing aneurysm surveillance, mostly carried out by contrast-enhanced computed tomography angiography (CTA). Purpose To prospectively compare image quality and reliability of a prototype non-contrast, self-navigated 3D whole-heart magnetic resonance angiography (MRA) with contrast-enhanced computed tomography angiography (CTA) for sizing of thoracic aortic aneurysm (TAA). Methods Self-navigated 3D whole-heart 1.5 T MRA was performed in 20 patients (aged 67 ± 8.6 years, 75% male) for sizing of TAA; a subgroup of 18 (90%) patients underwent additional contrast-enhanced CTA on the same day. Subjective image quality was scored according to a 4-point Likert scale and ratings between observers were compared by Cohen’s Kappa statistics. Continuous MRA and CTA measurements were analyzed with regression and Bland-Altman analysis. Results Overall subjective image quality as rated by two observers was 1 [interquartile range (IQR) 1-2] for self-navigated MRA and 1.5 [IQR 1-2] for CTA (p = 0.717). For MRA a perfect inter-observer agreement was found for presence of artefacts and subjective image sharpness (κ=1). Subjective signal inhomogeneity correlated highly with objectively quantified inhomogeneity of the blood pool signal (r = 0.78-0.824, all p <0.0001). Maximum diameters of TAA as measured by self-navigated MRA and CTA showed excellent correlation (r = 0.997, p < 0.0001) without significant inter-method bias (bias -0.0278, lower and upper limit of agreement -0.74 and 0.68, p = 0.749). Inter- and intraobserver correlation of aortic aneurysm as measured by MRA was excellent (r = 0.963 and 0.967, respectively) without significant bias (all p ≤ 0.05). Conclusion Self-navigated 3D whole-heart MRA enables reliable contrast- and radiation free aortic dilation surveillance without significant difference to standardized CTA while providing predictable acquisition time and by offering excellent image quality. Abstract Figure.

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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

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/s12968-021-00774-9 ◽

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.

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Value of bowel preparation techniques for prostate MRI: a preliminary study

Abdominal Radiology ◽

10.1007/s00261-021-03046-3 ◽

2021 ◽

Author(s):

Cynthia Schmidt ◽

Andreas M. Hötker ◽

Urs J. Muehlematter ◽

Irene A. Burger ◽

Olivio F. Donati ◽

...

Keyword(s):

Image Quality ◽

Bowel Preparation ◽

Statistical Tests ◽

Intraclass Correlation ◽

Geometric Distortion ◽

Significant Independent Predictor ◽

Contrast Enhanced ◽

Treatment Naïve ◽

Urogenital Imaging ◽

Study Type

Abstract Background Bowel preparation before multiparametric MRI (mpMRI) of the prostate is performed widely, despite contradictory or no evidence for efficacy. Purpose To investigate the value of hyoscine N-butylbromide (HBB), microenema (ME) and ‘dietary restrictions’ (DR) for artifact reduction and image quality (IQ) in mpMRI of the prostate. Study type Retrospective. Population Between 10/2018 and 02/2020 treatment-naïve men (median age, 64.9; range 39.8–87.3) who underwent mpMRI of the prostate were included. The total patient sample comprised of n = 180 patients, who received either HBB, ME, were instructed to adhere to DR, or received a combination of those measures prior to the MR scan. Field strength/sequence T2-weighted imaging (T2w), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced MRI (DCE-MRI) scanned on two 3T systems. Assessment A radiologist specialized in urogenital imaging (R1) and a senior radiology resident (R2) visually assessed IQ parameters on transversal T2w, DWI and ADC maps on a 5-point Likert-like scale. Statistical tests Group comparison between IQ parameters was performed on reader level using Kruskal–Wallis and Mann–Whitney U tests. Binary univariate logistic regression analysis was used to assess independent predictors of IQ. Interrater agreement was assessed using Intraclass Correlation Coefficient (ICC). Results ‘DWI geometric distortion’ was significantly more pronounced in the HBB+/ME−/DR− (R1, 3.6 and R2, 4.0) as compared to the HBB−/ME+/DR− (R1, 4.2 and R2, 4.6) and HBB+/ME+/DR− (R1, 4.3 and R2, 4.7) cohort, respectively. Parameters ‘DWI IQ’ and ‘Whole MRI IQ’ were rated similarly by both readers. ME was a significant independent predictor of ‘good IQ’ for the whole MRI for R1 [b = 1.09, OR 2.98 (95% CI 1.29, 6.87)] and R2 [b = 1.01, OR 2.73 (95% CI 1.24, 6.04)], respectively. Data conclusion ME seems to significantly improve image quality of DWI and the whole mpMRI image set of the prostate. HBB and DR did not have any benefit.

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Deep-learning-based image reconstruction in dynamic contrast-enhanced abdominal CT: image quality and lesion detection among reconstruction strength levels

Clinical Radiology ◽

10.1016/j.crad.2021.03.010 ◽

2021 ◽

Author(s):

T. Kaga ◽

Y. Noda ◽

K. Fujimoto ◽

T. Suto ◽

N. Kawai ◽

...

Keyword(s):

Deep Learning ◽

Image Reconstruction ◽

Image Quality ◽

Lesion Detection ◽

Ct Image ◽

Abdominal Ct ◽

Dynamic Contrast Enhanced ◽

Contrast Enhanced ◽

Ct Image Quality

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Quiescent-Interval Single-Shot Magnetic Resonance Angiography

Diagnostics ◽

10.3390/diagnostics8040084 ◽

2018 ◽

Vol 8 (4) ◽

pp. 84

Author(s):

Aman Saini ◽

Alex Wallace ◽

Hassan Albadawi ◽

Sailendra Naidu ◽

Sadeer Alzubaidi ◽

...

Keyword(s):

Magnetic Resonance ◽

Image Quality ◽

Magnetic Resonance Angiography ◽

Diagnostic Imaging ◽

Imaging Techniques ◽

Feasibility Studies ◽

Subsequent Treatment ◽

Single Shot ◽

Contrast Enhanced ◽

Diagnostic Imaging Techniques

Lower extremity peripheral arterial disease (PAD) is a chronic, debilitating disease with a significant global burden. A number of diagnostic imaging techniques exist, including computed tomography angiography (CTA) and contrast-enhanced magnetic resonance angiography (CEMRA), to aid in PAD diagnosis and subsequent treatment planning. Due to concerns of renal toxicity or nephrogenic systemic fibrosis (NSF) for iodinated and gadolinium-based contrasts, respectively, a number of non-enhanced MRA (NEMRA) protocols are being increasingly used in PAD diagnosis. These techniques, including time of flight and phase contrast MRA, have previously demonstrated poor image quality, long acquisition times, and/or susceptibility to artifacts when compared to existing contrast-enhanced techniques. In recent years, Quiescent-Interval Single-Shot (QISS) MRA has been developed to overcome these limitations in NEMRA methods, with promising results. Here, we review the various screening and diagnostic tests currently used for PAD. The various NEMRA protocols are discussed, followed by a comprehensive review of the literature on QISS MRA to date. A particular emphasis is placed on QISS MRA feasibility studies and studies comparing the diagnostic accuracy and image quality of QISS MRA versus other diagnostic imaging techniques in PAD.

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Contrast-Enhanced Magnetic Resonance Angiography Using a Novel Elastin-Specific Molecular Probe in an Experimental Animal Model

Contrast Media & Molecular Imaging ◽

10.1155/2018/9217456 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Carolin Reimann ◽

Julia Brangsch ◽

Jan Ole Kaufmann ◽

Lisa C. Adams ◽

David C. Onthank ◽

...

Keyword(s):

Magnetic Resonance ◽

Image Quality ◽

Magnetic Resonance Angiography ◽

Contrast Agent ◽

Mr Angiography ◽

Molecular Probe ◽

Time Resolved ◽

Clinical Dose ◽

Contrast Enhanced ◽

First Pass

Objectives. The aim of this study was to test the potential of a new elastin-specific molecular agent for the performance of contrast-enhanced first-pass and 3D magnetic resonance angiography (MRA), compared to a clinically used extravascular contrast agent (gadobutrol) and based on clinical MR sequences. Materials and Methods. Eight C57BL/6J mice (BL6, male, aged 10 weeks) underwent a contrast-enhanced first-pass and 3D MR angiography (MRA) of the aorta and its main branches. All examinations were on a clinical 3 Tesla MR system (Siemens Healthcare, Erlangen, Germany). The clinical dose of 0.1 mmol/kg was administered in both probes. First, a time-resolved MRA (TWIST) was acquired during the first-pass to assess the arrival and washout of the contrast agent bolus. Subsequently, a high-resolution 3D MRA sequence (3D T1 FLASH) was acquired. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) were calculated for all sequences. Results. The elastin-specific MR probe and the extravascular imaging agent (gadobutrol) enable high-quality MR angiograms in all animals. During the first-pass, the probes demonstrated a comparable peak enhancement (300.6 ± 32.9 vs. 288.5 ± 33.1, p>0.05). Following the bolus phase, both agents showed a comparable intravascular enhancement (SNR: 106.7 ± 11 vs. 102.3 ± 5.3; CNR 64.5 ± 7.4 vs. 61.1 ± 7.2, p>0.05). Both agents resulted in a high image quality with no statistical difference (p>0.05). Conclusion. The novel elastin-specific molecular probe enables the performance of first-pass and late 3D MR angiography with an intravascular contrast enhancement and image quality comparable to a clinically used extravascular contrast agent.

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Contrast Enhanced Ultrasound: Visualization of Far Field and Classification of Plaque in the Extracranial Carotid Arteries

Journal for Vascular Ultrasound ◽

10.1177/1544316718783739 ◽

2018 ◽

Vol 42 (3) ◽

pp. 109-115 ◽

Cited By ~ 1

Author(s):

Paige L. Rowland ◽

Michelle Colpitts ◽

Angela Malone ◽

Munis Raza ◽

Lenora L. Eberhart ◽

...

Keyword(s):

Image Quality ◽

Carotid Artery ◽

Carotid Arteries ◽

Carotid Artery Disease ◽

Plaque Morphology ◽

Far Field ◽

Contrast Enhanced Ultrasound ◽

Contrast Imaging ◽

Contrast Enhanced ◽

Artery Disease

Ultrasound stratification for the degree of carotid artery disease based solely on lumen reduction has poorly predicted patient outcomes. This pilot study focused on patients with moderate carotid artery stenosis. Our purpose was to use contrast imaging with ultrasound to improve carotid field. A total of 10 patients diagnosed with moderate carotid artery stenosis were rescanned with an administration of a contrast imaging agent. Two-dimensional (2D) imaging, color, and Doppler were utilized to scan the patients. The 20 carotid arteries were blindly read by 2 experienced physicians. Visualization of far field, quality of Doppler envelope, plaque morphology, and overall image quality were semi-quantifiably assessed. With the use of a contrast imaging agent, there was a reduction in interphysician interpretation variability. The Kappa coefficient yielded an increase in agreement for postcontrast imaging in the majority of variables. The Doppler envelope showed improvement from precontrast (0.06) to postcontrast (0.63). The visualization of the far fields demonstrated a significant increase in agreement (0.77, 0.71, and 0.67) postcontrast. Plaque morphology demonstrated enhancement in characterization with contrast (–0.09 to 0.66). In this study, contrast-enhanced ultrasound (CEUS) was found to increase overall image quality. Improved interpretation can enhance risk stratification and with further exploration could be used to guide treatment plans for patients with asymptomatic moderate carotid artery disease.

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4159 Prostate cancer multiparametric MRI comparison study of 3T versus 7T in terms of lesion detection and image quality

Journal of Clinical and Translational Science ◽

10.1017/cts.2020.141 ◽

2020 ◽

Vol 4 (s1) ◽

pp. 35-35

Author(s):

Ethan Leng ◽

Benjamin Spilseth ◽

Anil Chauhan ◽

Joseph Gill ◽

Ana Rosa ◽

...

Keyword(s):

Prostate Cancer ◽

Image Quality ◽

Cancer Detection ◽

Quality Characteristics ◽

Multiparametric Mri ◽

Lesion Detection ◽

7 Tesla ◽

Contrast Enhanced ◽

Technological Developments ◽

Study Population

OBJECTIVES/GOALS: The goal of this study was to perform a comparative, multi-reader, retrospective clinical evaluation of prostate multiparametric MRI (mpMRI) at 3 Tesla (3T) vs. 7 Tesla (7T) primarily in terms of prostate cancer localization. Subjective measures of image quality and artifacts were also evaluated. METHODS/STUDY POPULATION: Nineteen subjects were imaged at 3T and 7T between March 2016 and October 2018 under IRB-approved protocols. Four radiologists retrospectively and independently reviewed the data, and completed a two-part assessment for each dataset. First, readers assessed likelihood of cancer using Prostate Imaging Reporting & Data System (PI-RADS) guidelines. Accuracy of cancer detection was compared to findings from prostate biopsy. The numbers of correctly or incorrectly classified sextants were summed across all four readers, then used to summarize detection performance. Second, readers assigned a score on a five-point Likert scale to multiple image quality characteristics for the 3T and 7T datasets. RESULTS/ANTICIPATED RESULTS: Sensitivity and specificity of 3T and 7T datasets for sextant-wise cancer detection were compared by paired two-tailed t-tests. Readers identified more sextants harboring cancer with the 3T datasets while false-positive rates were similar, resulting in significantly higher sensitivity at 3T with no significant differences in specificity. Likert scores for image quality characteristics for 3T and 7T datasets were compared by applying paired two-tailed t-tests to mean scores of the four radiologists for each dataset. Readers generally preferred the 3T datasets, in particular for staging and assessment of extraprostatic extension as well as overall quality of the contrast-enhanced data. DISCUSSION/SIGNIFICANCE OF IMPACT: Readers agreed 7T prostate mpMRI produced images with more anatomic detail, though with equivocal clinical relevance and more pronounced artifacts. Reader unfamiliarity with 7T images is a major extenuating factor. Forthcoming technological developments are anticipated to improve upon the results.

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4933Comparison of left ventricular global longitudinal strain measurements using contrast-enhanced and non-contrast echocardiographic images

European Heart Journal ◽

10.1093/eurheartj/ehz746.0003 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

S Liang

Keyword(s):

Image Quality ◽

Contrast Agents ◽

Longitudinal Strain ◽

Systolic Function ◽

Global Longitudinal Strain ◽

Left Ventricular Systolic Function ◽

Left Ventricular ◽

Ventricular Systolic Function ◽

Contrast Enhanced ◽

Contrast Enhanced Echocardiography

Abstract Background Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) are two important index for the quantification of left ventricular systolic function. With the help of ultrasound contrast agents, we can improve the definition of endocardial borders and allow the quantification of LVEF in patients with poor image quality. However, the feasibility of GLS measurements in contrast-enhanced images is still controversial. Purpose Our study aimed to explore the feasibility of GLS measured by velocity vector imaging (VVI) in contrast-enhanced images, compare the difference of measurements in contrast-enhanced and non-contrast images, and analyze the relation between LVEF and GLS in both conditions. Methods A total of 133 patients with cancer, who were registered for transthoracic echocardiography as well as contrast-enhanced echocardiography were studied. LVEF was measured using the biplane modified Simpson's rule and GLS was measured with offline VVI analysis of the three standard apical views in non-contrast and contrast-enhanced images respectively. Linear regression was performed to derive correlation coefficients between LVEF and GLS both in non-contrast and contrast-enhanced images. Results GLS measurements in non-contrast images were discarded in 2/133 patients (1.5%), while in contrast-enhanced images were obtained in all patients. LVEF (64.12±7.47% vs. 66.25±8.61%, respectively; P<0.01) and GLS (−20.99±4.67% vs. −23.40±4.58%, respectively; P<0.01) were both significantly higher in the presence of contrast agents. A linear regression between LVEF and GLS in non-contrast images (r=0.627, P<0.001) was observed, as well as in contrast-enhanced images (r=0.649, P<0.001). Conclusions GLS measured by VVI in contrast-enhanced echocardiography is a feasible and reliable index for the quantification of left ventricular systolic function, even in patients with poor image quality. Compared with the measurements in non-contrast images, both LVEF and GLS measurements are higher in the presence of contrast agents.

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