scholarly journals Infragenual cuff-compression reduces venous contamination in contrast-enhanced MR angiography of the calf

2004 ◽  
Vol 20 (2) ◽  
pp. 347-351 ◽  
Author(s):  
Deniz Bilecen ◽  
Anja-Carina Schulte ◽  
Georg Bongartz ◽  
Hanns-Georg Heidecker ◽  
Markus Aschwanden ◽  
...  
Keyword(s):  
Mr Angiography ◽  
Contrast Enhanced ◽  
Venous Contamination

High Resolution Contrast-Enhanced MR Angiography in the Evaluation of Rabbit Carotid Artery

2005 ◽  
Vol 18 (5-6) ◽  
pp. 529-536
Author(s):  
R.-H. Wu ◽  
D.F. Kallmes
Keyword(s):  
High Resolution ◽  
Image Quality ◽  
Carotid Artery ◽  
Mr Angiography ◽  
Flip Angle ◽  
Acquisition Time ◽  
Pixel Size ◽  
Rabbit Carotid Artery ◽  
Contrast Enhanced ◽  
Venous Contamination

This study compared a high resolution contrast-enhanced MR angiography (MRA) sequence to conventional contrast-enhanced MRA sequence for imaging of rabbit carotid artery. Fifteen rabbits underwent an evaluation using both high resolution contrast-enhanced MRA sequence and conventional contrast-enhanced MRA sequence. Siemens 1.5 Tesla Magnetom Vision system was utilized. The parameters of high resolution sequence were: TR/TE= 6.2/2.0 msec, flip angle 25°, matrix 130×512, pixel size 0.96×0.49 mm, partition thickness 1.58 mm, acquisition time 24 sec. The parameters of conventional sequence were: TR/TE=3.8/1.4 msec, flip angle 35°, matrix 110×256, pixel size 1.48×1.02 mm, partition thickness 2mm, acquisition time 10 sec. Maximum intensity projection (MIP) images were created. Both original single slices and MIP images were used for image quality evaluation. Contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), distinctness of artery edge, and venous contamination were analyzed for both techniques. Higher average CNR and SNR were obtained with high resolution contrast-enhanced MRA, compared to average CNR and SNR with conventional contrast-enhanced MRA. The differences were statistically significant (P<0.01). The artery edge with high resolution method was more distinct than conventional method. Jugular venous contamination was found in five of 15 cases with high resolution contrast-enhanced MRA and in four of 15 cases with conventional contrast-enhanced MRA. High resolution contrast-enhanced MRA has significant potential for high quality noninvasive vascular imaging. The image quality with high resolution contrast-enhanced MRA sequence is better than conventional contrast-enhanced MRA sequence.

Time-resolved, contrast-enhanced 3D MR angiography in the subclavian steal effect

VASA ◽  
2010 ◽  
Vol 39 (1) ◽  
pp. 85-93 ◽  
Author(s):  
Schubert
Keyword(s):  
Mr Angiography ◽  
Time Resolved ◽  
Time To Peak ◽  
Vertebral Arteries ◽  
Subclavian Steal ◽  
Cerebrovascular Events ◽  
Graphic Analysis ◽  
Contrast Enhanced ◽  
Hemodynamic Information ◽  
Supraaortic Vessels

The subclavian steal effect indicates atherosclerotic disease of the supraaortic vessels but rarely causes cerebrovascular events in itself. Noninvasive imaging providing detailed anatomic as well as hemodynamic information would therefore be desirable. From a group of 25 consecutive patients referred for MR angiography, four with absent or highly attenuated signal in one of the vertebral arteries on 3D multislab time-of-flight MR angiography were selected to undergo 3D time-resolved contrast-enhanced MR angiography. The time-resolved 3D contrast series (source images and MIPs) were evaluated visually and by graphic analysis of time-intensity curves derived from the respective V1 and V3 segments of both vertebral arteries on the source images. In two cases with high-grade proximal left subclavian stenosis, time-resolved 3D ce-MRA was able to visualise retrograde contrast filling of the left VA. There was a marked delay in time-to-peak between the left and right V1 segments in one case and a shallower slope of enhancement in another. In the other two cases, there was complete or collateralised segmental occlusion of the VAs.

Coarctation of the abdominal aorta: Demonstration of a rare anomaly using contrast-enhanced MR-angiography

VASA ◽  
2009 ◽  
Vol 38 (1) ◽  
pp. 66-71 ◽  
Author(s):  
Schubert
Keyword(s):  
Abdominal Aorta ◽  
Mr Angiography ◽  
Parallel Imaging ◽  
Left Renal Vein ◽  
Systemic Hypertension ◽  
Contrast Enhanced ◽  
Younger Age ◽  
Maximum Intensity Projections ◽  
Collateral Vessels ◽  
First Time

We describe a case of aortic coarctation at the level of the infrarenal abdominal aorta which is encountered in less than six individuals in one million. In contrast to aortic narrowing above or including the renal arteries, this seems to be a relatively benign anomaly without systemic hypertension or impaired renal function. For the first time in this type of anomaly, contrast-enhanced MR angiography (ce-MRA) on a multi-receiver channel MR system, with an 8-channel phased array coil and parallel imaging was used. Ce-MRA displayed a tortuous, narrowed aortic segment that was found to be associated with mesenteric artery stenosis and compression of the orthotopic left renal vein, also known as the nutcracker phenomenon. All major aortic branches could be depicted using 3D surface-shaded displays and subvolume maximum intensity projections (MIPs). Collateral vessels of the abdominal wall were identified using whole-volume MIPs. Since the majority of aortic malformations are diagnosed at a younger age, and many suffer from renal insufficiency, we conclude that ce-MRA will eventually place conventional DSA as the modality of choice in malformations of the abdominal aorta.

Value of a Bolus-Tagging Method on Contrast-Enhanced Abdominal MR Angiography

1999 ◽  
Vol 41 (4) ◽  
pp. 705
Author(s):  
Mi Ra Seo ◽  
Moon Gyu Lee ◽  
Hyuk Jin Hong ◽  
Hyun Kwon Ha ◽  
Pyo Nyun Kim ◽  
...  
Keyword(s):  
Mr Angiography ◽  
Contrast Enhanced

Contrast-Enhanced MR Angiography of Failing Hemodialysis Arteriovenous Fistulas and Grafts: A Preliminary Experience

2004 ◽  
Vol 51 (6) ◽  
pp. 609
Author(s):  
Young Sun Lee ◽  
Gong Yong Jin ◽  
Young Min Han ◽  
Sang Yong Lee ◽  
Hak Hun Park ◽  
...  
Keyword(s):  
Mr Angiography ◽  
Arteriovenous Fistulas ◽  
Contrast Enhanced

Partial Fat-saturated Contrast-enhanced Three-dimensional MR Angiography Compared with Non-Fat-saturated and Conventional Fat-saturated MR Angiography

Radiology ◽  
2000 ◽  
Vol 216 (1) ◽  
pp. 298-303 ◽  
Author(s):  
Paul R. Hilfiker ◽  
Robert J. Herfkens ◽  
Steve G. Heiss ◽  
Marcus T. Alley ◽  
Dominik Fleischmann ◽  
...  
Keyword(s):  
Mr Angiography ◽  
Three Dimensional ◽  
Contrast Enhanced

Clinical value of classification of venous malformations with contrast-enhanced MR Angiography

2016 ◽  
Vol 32 (9) ◽  
pp. 628-633 ◽  
Author(s):  
Ahmed Abdel Khalek Abdel Razek ◽  
Germeen Ashmalla Albair ◽  
Sieza Samir
Keyword(s):  
Mr Angiography ◽  
Treatment Plan ◽  
Venous Malformation ◽  
Observer Agreement ◽  
Type I ◽  
Venous Malformations ◽  
Single Measure ◽  
Intra Class Correlation ◽  
Contrast Enhanced

Aim To classify venous malformations based on contrast-enhanced MR angiography that may serve as a basis for treatment plan. Patients and methods A retrospective analysis was performed in 58 patients with venous malformations who underwent contrast-enhanced MR angiography. Venous malformations were classified according to their venous drainage into: type I, isolated malformation without peripheral drainage; type II, malformation that drains into normal veins; type III, malformation that drains into dilated veins; and type IV, malformation that represents dysplastic venous ectasia. Image analysis was done by two reviewers. Intra and inter-observer agreement of both reviewers and intra-class correlation was done. Results The intra-observer agreement of contrast-enhanced MR angiography classification of venous malformations was excellent for the first reviewer ( k = 0.83, 95% CI = 0.724–0.951, P = 0.001) and substantial for the second reviewer ( K = 0.79, 95% CI = 0.656-0.931, P = 0.001). The inter-observer agreement of contrast-enhanced MR angiography classification of venous malformations was excellent for both reviewers at the first time ( K = 0.96, 95% CI = 0.933–1.000, P = 0.001) and second time ( k = 0.81, 95% CI = 0.678–0.942, P = 0.001). There was high intra-class correlation of both reviewers for single measure ( ICC = 0.85, 95% CI = 0.776–0.918, P = 0.001) and for average measures ( ICC = 0.96, 95% CI = 0.933–0.978, P = 0.001). Conclusion Contrast-enhanced MR angiography classification of venous malformations may be a useful, simple and reliable tool to accurately classify venous malformation and this topographic classification helps for better management strategy.

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