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Objectives: This study was conducted in order to compare a high resolution, non-contrast-enhanced MRA (NATIVE SPACE, NE-MRA) of the pedal vasculature with contrast-enhanced MRA (CE-MRA) and digital subtraction angiography (DSA) in patients with peripheral arterial occlusive disease (PAOD).Methods: The prospective study consists of 20 PAOD patients. All patients underwent percutaneous transluminal angioplasty or stenting and received MR angiographies the following day.Results: With CE-MRA, 75.7 % of vessel segments showed good, 16.4 % suboptimal and 7.9 % not usable image quality. With NE-MRA, 64.6 % showed good, 18.6 % suboptimal and 16.8 % not usable image quality. CE-MRA showed a sensitivity and negative predictive value of 90 %/95 % regarding significant stenosis (greater than 50 %), and specificity and positive predictive value were 88 %/77 %. Accordingly, sensitivity and negative predictive value for the NE-MRA were 96 %/97 % and specificity and positive predictive value were 80 %/69 % for stenoses greater than 50 %.Conclusions: The applied NE-MRA technique achieves high diagnostic accuracy even in very small distal arteries of the foot. However, the rate of non-diagnostic vessel segments is considerably higher for NE-MRA than for CE-MRA. NE-MRA is a valuable alternative to CE-MRA in selected patients.Key Points: • Comparison of non-enhanced MRA with contrast-enhanced MRA and DSA as gold standard. • High resolution MRA at 3 T for the depiction of small pedal vessels. • Evaluation of high resolution non-enhanced MRA in PAOD patients. [ABSTRACT FROM AUTHOR]

Objective: To investigate the feasibility of subtractionless first-pass single contrast medium dose (0.1 mmol/kg) peripheral magnetic resonance angiography (MRA) at 1.5 T using two-point Dixon fat suppression and compare it with conventional subtraction MRA in terms of image quality. Methods: Twenty-eight patients (13 male, 15 female; mean age ± standard deviation, 66 ± 16 years) with known or suspected peripheral arterial disease underwent subtractionless and subtraction first-pass MRA at 1.5 T using two-point Dixon fat suppression. Results were compared with regard to vessel-to-background contrast. A phantom study was performed to assess the signal-to-noise ratio (SNR) of both MRA techniques. Two experienced observers scored subjective image quality. Agreement regarding subjective image quality was expressed in quadratic weighted κ values. Results: Vessel-to-background contrast improved in all anatomical locations with the subtractionless method versus the subtraction method (all P < 0.001). Subjective image quality was uniformly higher with the subtractionless method (all P < 0.03, except for the aorto-iliac arteries for observer 1, P = 0.052). SNR was 15 % higher with the subtractionless method (31.9 vs 27.6). Conclusion: This study demonstrates the feasibility of subtractionless first-pass single contrast medium dose lower extremity MRA. Moreover, both objective and subjective image quality are better than with subtraction MRA. Key Points: • MRA is increasingly used for vascular applications. • Dixon imaging offers an alternative to image subtraction for fat suppression. • Subtractionless first-pass peripheral MRA is possible using two-point Dixon fat suppression. • Subtractionless peripheral MRA is possible at 1.5 T a single contrast medium dose. • Subtractionless first-pass peripheral MRA provides good image quality with few non-diagnostic studies. [ABSTRACT FROM AUTHOR]

Foot complications associated with diabetes are the most common cause of non-traumatic lower-extremity amputations in the industrialised countries. Revascularisation techniques require precise preoperative imaging. Magnetic resonance angiography (MRA) using gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) has the potential to detect significantly more patent pedal vessel segments than selective digital substractive angiography (DSA) in an examination with two blinded readers. MRI and MRA are the imaging methods of choice for differentiated assessment of the diabetic foot and its complications, and they are robust techniques for delineating the pedal macrocirculation. Therefore, they should play a central role in the management of patients with a diabetic foot syndrome. [ABSTRACT FROM AUTHOR]

High-resolution total-body 3D MR angiography (MRA) has recently become available, revealing additional clinically relevant disease in patients with peripheral arterial occlusive disease (PAOD). However, the actual impact of total-body MRA on patient management in patients with PAOD has not been investigated so far. Two hundred forty-nine consecutive patients with angiographically proven PAOD were prospectively examined by means of contrast-enhanced total-body 3D MRA on a 1.5-T MR scanner. All correlative imaging studies performed within 60 days of total-body MRA were included in the efficacy analysis. Additional clinically relevant disease (luminal narrowing >50%, aneurysmal changes or dissections) was found in 73 segments (52 patients), including the renal arteries (36 segments), carotid arteries (28 segments), subclavian arteries (four segments) and abdominal aortic aneurysms (AAA) (five segments). Of the 73 segments, 36 were deemed necessary for further investigation by means of focused MRA examinations; the diagnosis was confirmed in all cases. Within the 60-day follow-up period, interventional or surgical therapy outside the peripheral arterial tree was performed in nine patients (11 segments), including carotid endatherectomy and renal artery angioplasty. The outlined total-body 3D MRA approach permits a comprehensive evaluation of the arterial system in patients with atherosclerosis and does indeed have an impact on patient management in patients with PAOD. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare moving-table three-dimensional contrast-enhanced magnetic resonance angiography (CE MRA), using 1.0-mol gadobutrol, with intra-arterial digital subtraction angiography (i.a. DSA) for evaluation of pelvic and peripheral arteries in patients with peripheral arterial occlusive disease. A total of 203 patients were examined in a prospective, multi-centre study at 1.0/1.5 T. Ten vessel segments of one leg were evaluated on-site and by three independent blinded reviewers off-site. One hundred eighty-two patients were evaluable in blinded reading. For pelvis and thigh, there was statistically significant diagnostic agreement between CE MRA and i.a. DSA on-site (94%) and off-site (86-88%). Overall, for detection of clinically significant stenoses, 93% sensitivity and 90% specificity were achieved in on-site evaluation, with 71-76 and 87-93% off-site; for detection of occlusion, sensitivity and specificity on-site were 91 and 97%, with 75-82 and 94-98% off-site. Evaluation was more sensitive on-site than off-site for detection of stenoses and occlusion, whereas specificity was similar. The CE MRA with 1.0-mol gadobutrol gave results comparable to those of i.a. DSA for the larger arteries of pelvis and thigh. Results for calf arteries were compromised by spatial resolution and technical limitations. [ABSTRACT FROM AUTHOR]