MR angiography

2018 ◽  
pp. 34-37
Author(s):  
Sebastian Kozerke ◽  
Redha Boubertakh ◽  
Marc Miquel
Keyword(s):  
Spin Echo ◽  
Time Of Flight ◽  
Flow Quantification ◽  
Black Blood ◽  
Blood Flows ◽  
Contrast Enhanced ◽  
Stationary Signals ◽  
Contrast Mechanism ◽  
Contrast Angiography ◽  
Spin Echo Sequences

The appearance of blood on magnetic resonance (MR) images is directly linked to its flowing nature. The contrast mechanism relies on the time-of-flight mechanism. In spin echo sequences, the excited blood flows out before the echo is created, resulting in black blood images, whereas in gradient echo images, the rapid succession of radiofrequency pulses saturates stationary signals, while fresh blood continuously flows in, leading to bright blood images. This phenomenon can be exploited to create inflow or time-of-flight angiography. It is also possible to encode the movement by using gradients that create phase differences between stationary and moving tissues. This technique, known as phase contrast angiography, can be used to image the venous and arterial phases separately. It also forms the basics of blood flow quantification. Finally, it is possible to use gadolinium-based agents to acquire contrast-enhanced angiographies.

scholarly journals Improvement of the Diagnostic Performance of Facial Neuritis Using Contrast-Enhanced 3D T1 Black-Blood Imaging: Comparison with Contrast-Enhanced 3D T1-Spoiled Gradient-Echo Imaging

2021 ◽  
Vol 10 (9) ◽  
pp. 1850
Author(s):  
Seun-Ah Lee ◽  
Sang-Won Jo ◽  
Suk-Ki Chang ◽  
Ki-Han Kwon
Keyword(s):  
Quantitative Analysis ◽  
Diagnostic Performance ◽  
Spin Echo ◽  
Fast Spin Echo ◽  
Black Blood ◽  
Gradient Echo ◽  
Diagnostic Confidence ◽  
Contrast Enhanced ◽  
Black Blood Imaging ◽  
Spoiled Gradient Echo

This study aims to investigate the diagnostic ability of the contrast-enhanced 3D T1 black-blood fast spin-echo (T1 BB-FSE) sequence compared with the contrast-enhanced 3D T1-spoiled gradient-echo (CE-GRE) sequence in patients with facial neuritis. Forty-five patients with facial neuritis who underwent temporal bone MR imaging, including T1 BB-FSE and CE-GRE imaging, were examined. Two reviewers independently assessed the T1 BB-FSE and CE-GRE images in terms of diagnostic performance, and qualitative (diagnostic confidence and visual asymmetric enhancement) and quantitative analysis (contrast-enhancing lesion extent of the canalicular segment of the affected facial nerve (LEC) and the affected side-to-normal signal intensity ratio (rSI)). The AUCs of each reviewer, and the sensitivity and accuracy of T1 BB-FSE were significantly superior to those of CE-GRE (p < 0.05). Regarding diagnostic confidence and visual asymmetric enhancement, T1 BB-FSE tended to be rated greater than CE-GRE (p < 0.05). Additionally, in quantitative analysis, LEC and rSI of the canalicular segment on T1 BB-FSE were larger than those on CE-GRE (p < 0.05). The T1 BB-FSE sequence was significantly superior to the CE-GRE sequence, with more conspicuous lesion visualization in terms of both qualitative and quantitative aspects in patients with facial neuritis.

scholarly journals MR imaging by 3D T1-weighted black blood sequences may improve delineation of therapy-naive high-grade gliomas

2020 ◽  
Author(s):  
Tom Finck ◽  
Jens Gempt ◽  
Claus Zimmer ◽  
Jan S. Kirschke ◽  
Nico Sollmann
Keyword(s):  
Contrast Enhancement ◽  
Spin Echo ◽  
World Health ◽  
Black Blood ◽  
High Grade ◽  
Who Grade ◽  
Oncological Treatment ◽  
Contrast Enhanced ◽  
High Grade Gliomas ◽  
Turbo Field Echo

Abstract Objectives To investigate the value of contrast-enhanced (CE) turbo spin echo black blood (BB) sequences for imaging of therapy-naive high-grade gliomas (HGGs). Methods Consecutive patients with histopathologically confirmed World Health Organization (WHO) grade III or IV gliomas and no oncological treatment prior to index imaging (March 2019 to January 2020) were retrospectively included. Magnetic resonance imaging (MRI) at 3 Tesla comprised CE BB and CE turbo field echo (TFE) sequences. The lack/presence of tumor-related contrast enhancement and satellite lesions were evaluated by two readers. Sharper delineation of tumor boundaries (1, bad; 2, intermediate; 3, good delineation) and vaster expansion of HGGs into the adjacent brain parenchyma on CE BB imaging were the endpoints. Furthermore, contrast-to-noise ratios (CNRs) were calculated and compared between sequences. Results Fifty-four patients were included (mean age: 61.2 ± 15.9 years, 64% male). The vast majority of HGGs (51/54) showed contrast enhancement in both sequences, while two HGGs as well as one of six detected satellite lesions were depicted in CE BB imaging only. Tumor boundaries were significantly sharper (R1: 2.43 ± 0.71 vs. 2.73 ± 0.62, p < 0.001; R2: 2.44 ± 0.74 vs. 2.77 ± 0.60, p = 0.001), while the spread of HGGs into the adjacent parenchyma was larger when considering CE BB sequences according to both readers (larger spread in CE BB sequences: R1: 23 patients; R2: 20 patients). The CNR for CE BB sequences significantly exceeded that of CE TFE sequences (43.4 ± 27.1 vs. 32.5 ± 25.0, p = 0.0028). Conclusions Our findings suggest that BB imaging may considerably improve delineation of therapy-naive HGGs when compared with established TFE imaging. Thus, CE BB sequences might supplement MRI protocols for brain tumors. Key Points • This study investigated contrast-enhanced (CE) T1-weighted black blood (BB) sequences for improved MRI in patients with therapy-naive high-grade gliomas (HGGs). • Compared with conventionally used turbo field echo (TFE) sequences, CE BB sequences depicted tumor boundaries and spread of HGGs into adjacent parenchyma considerably better, which also showed higher CNRs. • Two enhancing tumor masses and one satellite lesion were exclusively identified in CE BB sequences, but remained undetected in conventionally used CE TFE sequences.

Modified electrocardiograph-triggered black-blood turbo spin-echo technique to improve T1-weighting in contrast-enhanced MRI of atherosclerotic carotid arteries

2008 ◽  
Vol 28 (2) ◽  
pp. 533-537 ◽  
Author(s):  
Loic Boussel ◽  
Gwenael Herigault ◽  
Monica Sigovan ◽  
Romaric Loffroy ◽  
Emmanuelle Canet-Soulas ◽  
...  
Keyword(s):  
Carotid Arteries ◽  
Spin Echo ◽  
Black Blood ◽  
Turbo Spin Echo ◽  
Turbo Spin ◽  
Enhanced Mri ◽  
Contrast Enhanced ◽  
Spin Echo Technique ◽  
Contrast Enhanced Mri
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