Venous phase image show mild wall thickening along the ascending aorta. Image quality is limited, but findings are better seen in the venous phase image

ASVIDE ◽  
2018 ◽  
Vol 5 ◽  
pp. 325-325
Author(s):  
Paul Schoenhagen
Keyword(s):  
Image Quality ◽  
Ascending Aorta ◽  
Phase Image ◽  
Wall Thickening ◽  
Venous Phase

Image Quality Analysis of X-ray Grating Interferometer Using Integrating-bucket Method

2020 ◽  
Vol 64 (2) ◽  
pp. 20503-1-20503-5
Author(s):  
Faiz Wali ◽  
Shenghao Wang ◽  
Ji Li ◽  
Jianheng Huang ◽  
Yaohu Lei ◽  
...  
Keyword(s):  
Image Quality ◽  
Phase Contrast ◽  
Quality Analysis ◽  
Phase Contrast Imaging ◽  
Phase Image ◽  
Contrast Imaging ◽  
High Quality ◽  
Image Quality Analysis ◽  
X Ray ◽  
Grating Interferometer

Abstract Grating-based x-ray phase-contrast imaging has the potential to enhance image quality and provide inner structure details non-destructively. In this work, using grating-based x-ray phase-contrast imaging system and employing integrating-bucket method, the quantitative expressions of signal-to-noise ratios due to photon statistics and mechanical error are analyzed in detail. Photon statistical noise and mechanical error are the main sources affecting the image noise in x-ray grating interferometry. Integrating-bucket method is a new phase extraction method translated to x-ray grating interferometry; hence, its image quality analysis would be of great importance to get high-quality phase image. The authors’ conclusions provide an alternate method to get high-quality refraction signal using grating interferometer, and hence increases applicability of grating interferometry in preclinical and clinical usage.

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 How Can We Manage Gallbladder Lesions by Transabdominal Ultrasound?

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 784
Author(s):  
Shinji Okaniwa
Keyword(s):  
High Frequency ◽  
Layer Structure ◽  
Wall Layer ◽  
Pancreaticobiliary Maljunction ◽  
Doppler Imaging ◽  
Wall Thickening ◽  
Contrast Enhanced ◽  
Postural Changes ◽  
Venous Phase

The most important role of ultrasound (US) in the management of gallbladder (GB) lesions is to detect lesions earlier and differentiate them from GB carcinoma (GBC). To avoid overlooking lesions, postural changes and high-frequency transducers with magnified images should be employed. GB lesions are divided into polypoid lesions (GPLs) and wall thickening (GWT). For GPLs, classification into pedunculated and sessile types should be done first. This classification is useful not only for the differential diagnosis but also for the depth diagnosis, as pedunculated carcinomas are confined to the mucosa. Both rapid GB wall blood flow (GWBF) and the irregularity of color signal patterns on Doppler imaging, and heterogeneous enhancement in the venous phase on contrast-enhanced ultrasound (CEUS) suggest GBC. Since GWT occurs in various conditions, subdividing into diffuse and focal forms is important. Unlike diffuse GWT, focal GWT is specific for GB and has a higher incidence of GBC. The discontinuity and irregularity of the innermost hyperechoic layer and irregular or disrupted GB wall layer structure suggest GBC. Rapid GWBF is also useful for the diagnosis of wall-thickened type GBC and pancreaticobiliary maljunction. Detailed B-mode evaluation using high-frequency transducers, combined with Doppler imaging and CEUS, enables a more accurate diagnosis.

Split-Bolus Portal Venous Phase Dual-Energy CT Urography: Protocol Design, Image Quality, and Dose Reduction

2015 ◽  
Vol 205 (5) ◽  
pp. W492-W501 ◽  
Author(s):  
Chiao-Yun Chen ◽  
Jui-Sheng Hsu ◽  
Twei-Shiun Jaw ◽  
Ming-Chen Paul Shih ◽  
Lo-Jeh Lee ◽  
...  
Keyword(s):  
Image Quality ◽  
Dose Reduction ◽  
Dual Energy ◽  
Protocol Design ◽  
Dual Energy Ct ◽  
Ct Urography ◽  
Portal Venous Phase ◽  
Venous Phase

scholarly journals Coronary computed tomography angiography (CCTA): effect of bolus-tracking ROI positioning on image quality

2020 ◽  
Author(s):  
Heiner Nebelung ◽  
Thomas Brauer ◽  
Danilo Seppelt ◽  
Ralf-Thorsten Hoffmann ◽  
Ivan Platzek
Keyword(s):  
Image Quality ◽  
Left Atrium ◽  
Coronary Arteries ◽  
Coronary Computed Tomography Angiography ◽  
Pulmonary Arteries ◽  
Ascending Aorta ◽  
Triple Rule Out ◽  
Comparable Image Quality ◽  
Rule Out

Abstract Objectives The aim of the study was to evaluate the effect of bolus-tracking ROI positioning on coronary computed tomography angiography (CCTA) image quality. Methods In this retrospective monocentric study, all patients had undergone CCTA by step-and-shoot mode to rule out coronary artery disease within a cohort at intermediate risk. Two groups were formed, depending on ROI positioning (left atrium (LA) or ascending aorta (AA)). Each group contained 96 patients. To select pairs of patients, propensity score matching was used. Image quality with regard to coronary arteries as well as pulmonary arteries was evaluated using quantitative and qualitative scores. Results In terms of the coronary arteries, there was no significant difference between both groups using quantitative (SNR AA 14.92 vs. 15.46; p = 0.619 | SNR LM 19.80 vs. 20.30; p = 0.661 | SNR RCA 24.34 vs. 24.30; p = 0.767) or qualitative scores (4.25 vs. 4.29; p = 0.672), respectively. With regard to pulmonary arteries, we found significantly higher quantitative (SNR RPA 8.70 vs. 5.89; p < 0.001 | SNR LPA 9.06 vs. 6.25; p < 0.001) and qualitative scores (3.97 vs. 2.24; p < 0.001) for ROI positioning in the LA than for ROI positioning in the AA. Conclusions ROI positioning in the LA or the AA results in comparable image quality of CT coronary arteriography, while positioning in the LA leads to significantly higher image quality of the pulmonary arteries. These results support ROI positioning in the LA, which also facilitates triple-rule-out CT scanning. Key Points • ROI positioning in the left atrium or the ascending aorta leads to comparable image quality of the coronary arteries. • ROI positioning in the left atrium results in significantly higher image quality of the pulmonary arteries. • ROI positioning in the left atrium is feasible to perform triple-rule-out CTA.

scholarly journals Image quality and attenuation values of multidetector CT coronary angiography using high iodine-concentration contrast material: A comparison of the use of iopromide 300 and iopromide 370

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
A K M Darwish ◽  
M M Farouk ◽  
H Hafez ◽  
A Adel
Keyword(s):  
Image Quality ◽  
Pulmonary Artery ◽  
Coronary Arteries ◽  
Main Pulmonary Artery ◽  
Iodine Concentration ◽  
Ascending Aorta ◽  
P Value ◽  
Group A ◽  
The Mean ◽  
Attenuation Values

Abstract Background Iodine concentration is one of the main determinants of arterial enhancement in CTA, and current low-osmolar and iso-osmolar nonionic CM for intravascular administration still come in a handful of molecules, but a relatively wide range of different iodine concentrations. This gives the opportunity to optimize CTA protocols as a function of several factors such as patient characteristics, CT technology, and CM features in an attempt to maximize the diagnostic yield of CTA examinations while considering patient safety and avoiding unnecessary extra costs. Objective To compare image quality and attenuation values of multidetector CT coronary angiography (MDCT) between iopromide 300 and iopromide 370 and to evaluate whether the higher iodine contrast material has better image quality or not. Material and Methods Patients were prospectively enrolled and were randomized into two groups (group A, 30 patients received iopromide 300, iodine flux 1.2g I/s; group B, 30 patients received iomeprol 370, iodine flux 1.48g I/s). CT attenuation values were measured in the proximal end coronary arteries,ascending aorta and main pulmonary artery. The image quality of 15 coronary artery segments was graded by cardiologist in consensus with the use of a four-point scale (1 excellent enhancement to 4 poor enhancement). Non-parametric statistical approaches were used to compare the two groups. Results No statistically significant differences were found between the mean attenuation values (302 HU for iopromide 300 and 326 HU for iopromide 370, P = 0.175) in the coronary arteries in the two groups. The mean attenuation value of the proximal ascending aorta (AA)and main pulmonary artery (MPA) was found to be 345+/-63 HU and 241+/- 89 in group A respectively, whereas the mean attenuation value in proximal ascending aorta and main pulmonary artery in group B was found to be 348+/-74 and 238+/- 50 respectively. No significant difference was found between iopromide 300 and iopromide 370 in terms of contrast enhancement at the level of great arteries, P value AA = 0.826 and P value for MPA = 0.884. 92.9% of coronary arterial segments got score (range 1–2) in group A whereas 93.6 of coronary arterial segments got score (range 1-2) in group with no statistically significant difference P value = 0.755. Conclusion With the current CT technology iopromide 300 is not inferior to iopromide 370 in terms of coronary artery attenuation values and image quality. Iopromide 300 provides similar enhancement of coronary arteries and excellent image quality as compared with iopromide 370 using identical amount of total iodine with fewer cost and less estimated adverse effects owing to low iodine concentration of iopromide 300.

Venous-phase chest CT with reduced contrast medium dose: Utilization of spectral low keV monoenergetic images improves image quality

2020 ◽  
Vol 122 ◽  
pp. 108756
Author(s):  
Tilman Hickethier ◽  
Jan Robert Kroeger ◽  
Simon Lennartz ◽  
Jonas Doerner ◽  
David Maintz ◽  
...  
Keyword(s):  
Image Quality ◽  
Contrast Medium ◽  
Chest Ct ◽  
Venous Phase ◽  
Monoenergetic Images ◽  
Medium Dose

scholarly journals Contrast Media in Time-Resolved MRA at 3T: A Systematic Quantitative and Qualitative Analysis of Concentration and Dose Effects on Image Parameters in Minipigs

2018 ◽  
Vol 190 (08) ◽  
pp. 747-757
Author(s):  
Dariusch Hadizadeh ◽  
Vera Keil ◽  
Gregor Jost ◽  
Hubertus Pietsch ◽  
Martin Weibrecht ◽  
...  
Keyword(s):  
Image Quality ◽  
Qualitative Analysis ◽  
Standard Dose ◽  
Gadopentetate Dimeglumine ◽  
Time Resolved ◽  
Quality Ratings ◽  
Dose Effects ◽  
Venous Phase ◽  
The Difference ◽  
Multi Phase

Purpose Quantitative and qualitative analysis of gadopentetate dimeglumine (GD) versus standard-dose (sGb) and half-dose (hGb) gadobutrol in thoracoabdominal time-resolved contrast-enhanced magnetic resonance angiography (4D-MRA) with dynamic computed tomography (dCT) as the quantitative reference in minipigs. Materials and Methods 7 anesthetized Goettingen minipigs received thoracoabdominal dCT (0.37 s rotation time) and transverse 4D-MRA (0.3 s/dynamic frame;) using sGb and hGb. 8 other minipigs received coronal 4D-MRA (1.3 s/dynamic frame; sGb, hGb, SGD). dCT attenuation levels were converted into absolute gadolinium concentrations and compared to 4D-MRA peak signal intensities (SI). Bolus lengths were quantified by full width at half maximum (FWHM) measurements. After this comparison of dose effects on SI in transverse 4D-MRA, coronal 4D-MRAs were analyzed regarding both quantitative and qualitative parameters. Results In dCT (transverse 4D-MRA) hGb showed 39.0 % (14.5 %) lower arterial peak gadolinium concentrations (peak SIs) and 20.6 % (33.8 %) shorter FWHM compared to sGb. The difference was due to peak plateaus or reversals in 4D-MRA in 5/7 animals. While sGb led to the highest peak SIs, image quality ratings of arteries were rated similarly high with all contrast agent protocols despite a slightly higher SI with sGb. In contrast, venous peak SIs and image quality ratings were significantly higher when using sGb. Conclusion Peak Gd concentrations and 4D-MRA peak SIs are highest with sGB. These differences are most evident in the venous phase leading to superior image quality in multi-phase 4D-MRA. Key Points:  Citation Format

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