Comparison of gadodiamide‐enhanced MR angiography to intraarterial digital subtraction angiography for evaluation of renal artery stenosis: Results of a phase III multicenter trial

Purpose:

To evaluate the efficacy and safety of 0.1 mmol/kg gadodiamide administration for contrast‐enhanced magnetic resonance angiography (MRA) in detecting hemodynamically relevant renal artery stenosis (RAS) when compared with intraarterial digital subtraction angiography (IA‐DSA) as the gold standard.

Materials and Methods:

In a multicenter, controlled study, 395 patients with suspected or known RAS were included. Three independent readers evaluated the MRA images. Two readers evaluated the IA‐DSA images and subsequently achieved consensus. The sensitivities and specificities of gadodiamide‐enhanced MRA were analyzed at the per‐patient and per‐vessel levels (exact 1‐sided binomial test at α = 0.025 with 95% confidence interval).

Results:

A total of 335 patients who had available standard of truth and MRA tests were included in the all‐subjects efficacy population: 55.5% (186/335) men and 44.5% women with a mean age of 63 ± 13 years (range 17–85 years). The sensitivities and specificities ranged from 81% to 86% for all independent readers at the per‐patient analysis based on subjects with the diagnostic images. Similar results were achieved with per‐vessel level analysis. Fewer than 1% of patients had adverse event associated with gadodiamide administration. There were no cases of nephrogenic systemic fibrosis (NSF) reported.

Conclusion:

Gadodiamide administration at the labeled dose of 0.1 mmol/kg for contrast‐enhanced MRA achieved equivalent results compared to IA‐DSA in evaluation of RAS and was well tolerated. J. Magn. Reson. Imaging 2010; 31: 390–397. © 2010 Wiley‐Liss, Inc.     

Comparison of contrast‐enhanced multi‐station MR angiography and digital subtraction angiography of the lower extremity arterial disease

Purpose:

To compare diagnostic accuracy of multi‐station, high‐spatial resolution contrast‐enhanced MR angiography (CE‐MRA) of the lower extremities with digital subtraction angiography (DSA) as the reference standard in patients with symptomatic peripheral arterial occlusive disease.

Materials and Methods:

Of 485 consecutive patients undergoing a run‐off CE‐MRA, 152 patients (86 male, 66 female; mean age, 71.6 years) with suspected peripheral arterial occlusive disease were included into our Institutional Review Board approved study. All patients underwent MRA and DSA of the lower extremities within 30 days. MRA was performed at 1.5 Tesla with a single bolus of 0.1 mmol/kg body weight of gadobutrol administered at a rate of 2.0 mL/s at three stations. Two readers evaluated the MRA images independently for stenosis grade and image quality. Sensitivity and specificity were derived.

Results:

Sensitivity and specificity ranged from 73% to 93% and 64% to 89% and were highest in the thigh area. Both readers showed comparable results. Evaluation of good and better quality MRAs resulted in a considerable improvement in diagnostic accuracy.

Conclusion:

Contrast‐enhanced MRA demonstrates good sensitivity and specificity in the investigation of the vasculature of the lower extremities. While a minor investigator experience dependence remains, it is standardizable and shows good inter‐observer agreement. Our results confirm that the administration of Gadobutrol at a standard dose of 0.1 mmol/kg for contrast‐enhanced runoff MRA is able to detect hemodynamically relevant stenoses. Use of contrast‐enhanced MRA as an alternative to intra‐arterial DSA in the evaluation and therapeutic planning of patients with suspected peripheral arterial occlusive disease is well justified. J. Magn. Reson. Imaging 2013;37:1427–1435. © 2012 Wiley Periodicals, Inc.     

CT angiography of peripheral arterial occlusive disease

Lower extremity computed tomography angiography (CTA) is an effective, noninvasive, and robust imaging modality that is being used increasingly to evaluate patients with peripheral arterial occlusive disease (PAOD). It is important for vascular and interventional radiologists, and vascular surgeons to be familiar with the strengths and limitations, diagnostic accuracy, and practical application of lower extremity CTA. In this article, we review the technical principles of image acquisition, visualization techniques to effectively interpret the large volumetric datasets generated, and the current practical application of lower extremity CTA with respect to PAOD.     

Contrast-enhanced magnetic resonance angiography of the lower extremities: standard-dose vs. high-dose gadodiamide injection

PURPOSE: To compare the efficacy and safety of two different doses (0.1 and 0.3 mmol/kg of body weight [BW]) of gadodiamide for contrast-enhanced magnetic resonance angiography (ce-MRA) of the lower extremities with intraarterial digital subtraction angiography (IA-DSA). MATERIALS AND METHODS: A total of 30 patients with peripheral arterial occlusive disease underwent IA-DSA and ce-MRA from the aortic bifurcation down to the ankle. Patients were randomized to receive a total dose of 0.1 or 0.3 mmol/kg of BW gadodiamide (Omniscan, Amersham Buchler), administered intravenously as a series of three automatic bolus injections. Ce-MRA was performed with a 1.5-T system using a body phased-array coil, centered stepwise over the calf, thigh, and pelvic region. A fast T1-weighted, three-dimensional gradient-echo sequence was obtained before and after injection of the allocated dose. IA-DSA was performed using the Seldinger technique and a femoral approach. The vessels under investigation were divided into 31 segments, and ce-MRA and IA-DSA image sets were evaluated in a double-blind fashion for the presence of stenosis, presence of collateral vessels, vessel delineation, and overall image quality. Both dose groups were compared with regard to contrast index (CI) and signal- and contrast-to-noise ratios (SNR, CNR). The occurrence of adverse events or side effects was also documented. Sensitivity, specificity, and accuracy were calculated in relation to the results of stenosis grading. RESULTS: A total of 26 patients were entered in the efficacy evaluation, while all 30 patients were included in the safety assessment. The sensitivity, specificity, and accuracy for the 0.1 and 0.3 mmol/kg dose groups were 78.8%/93.0%/88.9% vs. 60.2.%/91.5%/83.2%, respectively. The detection of collaterals was similar to IA-DSA for the 0.3 mmol/kg dose group (30.2% vs. 27.4%), but was lower in the 0.1 mmol/kg dose group (27.3% vs. 12.3%). The high-dose gadodiamide injection proved to be superior to the 0.1 mmol/kg dose group with regard to vessel delineation and overall image quality (P = 0.007 and P = 0.002, respectively). The difference between the two dose groups regarding CI, SNR, and CNR was significant (P = 0.0001), in favor of the 0.3 mmol/kg dose group. No adverse events were observed in any of the patients. CONCLUSION: Ce-MRA with gadodiamide is safe and efficacious. Comparison of two different doses with IA-DSA as the standard of reference showed that the 0.3 mmol/kg dose is superior to the standard 0.1 mmol/kg dose with respect to contrast enhancement, vessel delineation, image quality, and detection of collaterals. However, the 0.1 mmol/kg dose was superior to the high dose in the grading of stenosis.     

Non‐contrast‐enhanced flow‐independent peripheral MR angiography with balanced SSFP

Flow‐independent angiography is a non‐contrast‐enhanced technique that can generate vessel contrast even with reduced blood flow in the lower extremities. A method is presented for producing these angiograms with magnetization‐prepared balanced steady‐state free precession (bSSFP). Because bSSFP yields bright fat signal, robust fat suppression is essential for detailed depiction of the vasculature. Therefore, several strategies have been investigated to improve the reliability of fat suppression within short scan times. Phase‐sensitive SSFP can efficiently suppress fat; however, partial volume effects due to fat and water occupying the same voxel can lead to the loss of blood signal. In contrast, alternating repetition time (ATR) SSFP minimizes this loss; however, the level of suppression is compromised by field inhomogeneity. Finally, a new double‐acquisition ATR‐SSFP technique reduces this sensitivity to off‐resonance. In vivo results indicate that the two ATR‐based techniques provide more reliable contrast when partial volume effects are significant. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.     

Analysis of subtraction methods in three-dimensional contrast-enhanced peripheral MR angiography

PURPOSE: To compare the effectiveness of three image subtraction algorithms designed to improve arterial conspicuity in first-pass contrast-enhanced magnetic resonance (MR) angiography. MATERIALS AND METHODS: Three subtraction methods were analyzed through computer simulations, phantom studies, and clinical studies. These algorithms were: complex subtraction, magnitude subtraction, and maximum intensity projection subtraction. RESULTS: In high resolution three-dimensional imaging, maximum intensity projection subtraction generally yields the best background suppression. Complex subtraction is effective in reducing partial volume effects in low resolution imaging. Magnitude subtraction works better in high resolution, low contrast concentration protocols. CONCLUSION: Choosing the appropriate subtraction method according to the protocol is helpful in optimizing image quality.     

3D contrast-enhanced MR angiography of the run-off vessels: value of image subtraction

The diagnostic gain associated with image subtractions was assessed regarding contrast-enhanced 3D magnetic resonance angiography (MRA) image sets of the pelvic and lower extremity arteries. The MRA strategy combined a dedicated vascular coil with a single injection, two-station protocol. Voxel-by-voxel signal intensity subtraction was performed on MRA image sets obtained before and during dynamic infusion of a para-magnetic contrast agent. Non-subtracted and subtracted MRA image sets were assessed for the presence of occlusive (four grades) disease, using DSA as the standard of reference. In addition, SNR and CNR were recorded for each vascular segment on both the non-subtracted and subtracted images. While CNR values of subtracted images exceeded those of non-subtracted images (P < 0.05), there was no difference in diagnostic performance. For the detection of hemodynamically significant disease, non-subtracted and subtracted MRA provided overall sensitivity and specificity of 90.2%/90.3% and 95.1%/95.6%, respectively. Concordance between non-subtracted and subtracted MRA was excellent (Kappa = 0.86).     

Timing algorithm for bolus chase MR digital subtraction angiography

Acquire multiple longitudinal locations in the lower extremity after a single contrast injection, appropriate table translation and contrast injection are required. An approximate model based on constant bolus velocity was developed to describe the space-time course of a contrast bolus in the lower extremity. This model was verified in dynamic MR angiograms acquired in a group of patients using time-resolved 2D MR digital subtraction angiography (MRDSA). From this contrast bolus passage model, a timing algorithm for table translation and contrast injection was developed for bolus chase MRDSA, subsequently validated in bolus chase 2D MRDSA experiments. All targeted major peripheral arteries were well depicted in bolus chase 2D MRDSA using this timing algorithm and a single 15-ml contrast dose.     

三维增强MR血管成像在周围型动脉闭塞症分级中的应用价值

目的探讨三维增强MR血管成像（3DCE-MRA）在周围型动脉闭塞症（PAOD）分级中的应用价值。方法选择25例临床诊断为PAOD的患者进行3D CE-MRA扫描，采用连续动床三段采集法，高压注射36ml钆喷替酸葡甲胺（GD-DTPA），将采集到的图像进行最大信号投影（MIP）、多平面重组（MPR）或者容积重组（VRT）。结果25例患者成功行3DCE-MRA检查，腹主动脉下段至小腿动脉显示对比度均可达到诊断要求，与DSA和（或）手术结果相比较，3DCE-MRA诊断PAOD总符合率达96．95％（509／525），诊断轻度狭窄、中度狭窄、重度狭窄和闭塞的符合率分别为84．62％（44／52）、84．85％（28／33）、95．45％（21／22）、98．67％（74／75），对轻度、中度、重度狭窄的高估率分别为11．54％（6／52）、12．12％（4／33）、4．55％（1／22），对轻度、中度、重度狭窄和闭塞的低估率分别为3．85％（2／52）、3．03％（1／33）、0（0／22）、1．33％（1／75）。结论3DCE-MRA可以对下肢动脉的狭窄和闭塞进行准确定位和分级，在临床应用中具有重要价值。     

Accuracy and safety of CO2 digital subtraction angiography during endovascular treatment of symptomatic peripheral artery occlusive disease. A prospective study on Egyptian patients

Purpose

To study the efficacy, safety and clinical outcome of carbon dioxide DSA during angioplasty procedures for patients with predominant femoropopliteal segment occlusive lesions, aiming to reduce possible allergic reactions and potential nephrotoxicity.

大脑中动脉狭窄的磁共振血管成像与数字减影血管造影的对照研究

目的 探讨磁共振血管成像(MRA)在大脑中动脉狭窄或闭塞病变中的诊断价值.方法 35例缺血性脑血管病患者先后行MRA及DSA检查,以DSA为金标准,分析MRA对不同程度大脑中动脉狭窄的诊断价值.结果 35例患者70支大脑中动脉中,MRA显示正常血管28支,病变血管42支,病变部位47处,MRA与DSA诊断符合53处,符...     

Improved multi-station peripheral MR angiography with a dedicated vascular coil

Delineation of small branch vessels can be crucial for assessing the peripheral arterial system of patients requiring surgical grafting. Thus signal-to-noise needs to be maximized. We evaluated the performance of a dedicated peripheral vascular coil in four subjects by comparing it to the body coil using DSA as the standard of reference. SNR and CNR values of the dedicated peripheral coil exceeded those obtained with the body coil by a mean of 398%, thus permitting improved delineation of the infrapopliteal arterial morphology.     

Highly accelerated contrast‐enhanced MR angiography: Improved reconstruction accuracy and reduced noise amplification with complex subtraction

Contrast‐enhanced magnetic resonance angiography is routinely performed using parallel imaging to best capture the first pass of contrast material through the target vasculature, followed by digital subtraction to suppress the appearance of unwanted signal from background tissue. Both processes, however, amplify noise and can produce uninterpretable images when large acceleration factors are used. Using a phantom study of contrast‐enhanced magnetic resonance angiography, we show that complex subtraction processing prior to partially parallel reconstruction improves reconstruction accuracy relative to magnitude subtraction processing for reduction factors as large as 12. Time‐resolved contrast‐enhanced magnetic resonance angiographic data obtainedwith complex subtraction in volunteers supported the results of the phantom study and when compared with magnitude subtraction processing demonstrated reduced geometry factors as well as improved image quality at large reduction factors. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.     

Noncontrast‐enhanced four‐dimensional MR angiography for the evaluation of cerebral arteriovenous malformation: A preliminary trial

Purpose:

To prospectively evaluate noncontrast‐enhanced (NCE), time resolved, four‐dimensional (4D) magnetic resonance angiography (MRA) for assessment of cerebral arteriovenous malformation (AVM), with intraarterial digital subtraction angiography (DSA) performed as the reference standard.

Materials and Methods:

Fifteen patients (ten men, five women; age range 2–59 years, mean 29.4 years) with 15 untreated cerebral AVMs comprised the study population. NCE 4D MRA was performed on a 3.0 T MR scanner. MR images were reviewed by two independent readers and compared with DSA with respect to arterial feeders, nidus size, and venous drainage. Kappa coefficients of concordance were computed to determine the interobserver and intermodality agreements for the depiction of arterial feeders, nidus, and venous drainage between the two techniques.

Results:

Fifteen AVMs detected in DSA were visualized in NCE 4D MRA. Intermodality agreements were excellent for the arterial feeders (K = 0.918, P = 0.000), good for the nidus size (K = 0.692, P = 0.000), and moderate for the venous drainage (K = 0.495, P = 0.001).

Conclusion:

NCE 4D MRA is a promising and potentially valuable method for noninvasive assessment of angioarchitecture and hemodynamics of cerebral AVMs. Further improvement of labeling persistence is desirable in order to enhance the depiction of draining veins for AVMs. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc.     

时间分辨随机轨道MR血管成像对周围动脉闭塞性疾病小腿动脉的成像研究

目的 评价3.0 T时间分辨随机轨道(TWIST)MRA提供的小腿动脉血流动力学指标和形态学诊断的价值.方法 40例临床证实或怀疑周围动脉闭塞性疾病(PAOD)的患者接受小腿段TWIST MRA及全下肢对比增强MRA(CE-MRA)检查.由TWIST MRA确定双侧腘动脉开始显示时间,双侧腘动脉开始显影时间差,小腿动脉通过时间和小腿动脉平均达峰时间.分析小腿动脉平均达峰时间与踝肱指数(ABI)的关系.评价小腿各段动脉在TWIST MRA及CE-MRA的图像显示情况,包括血管显示度、静脉重叠情况和动脉狭窄程度.组间比较采用t检验或校正t检验,动脉平均达峰时间与ABI的关系采用Pearson分析.对16例患者,以DSA为金标准,分别评价TWIST MRA、CE-MRA诊断各级动脉狭窄的敏感性和特异性.结果 (1)纳入评价的79侧下肢腘动脉开始显影时间为(30.7±7.6)s,双侧腘动脉开始显影时间差为(2.1±2.5)s,小腿动脉通过时间为(35.6±16.9)s,小腿动脉平均达峰时间为(52.6±17.6)s.(2)24例接受ABI检查的患者共计得到48个ABI指数(均值为0.62±0.23),与小腿动脉平均达峰时间呈正相关(r＝0.627,P＜0.01).(3)851段参与评价的血管中,TWIST MRA显影动脉节段849段,显示度评分为(2.83±0.48)分;CE-MRA显影动脉节段845段,显示度评分为(2.78±0.43)分(P＞0.05).(4)以DSA共显示的194段动脉节段为金标准,TWIST MRA显示正常及轻度狭窄的敏感性为96.7%(118/122)、特异性为100.0% (72/72),显示明显狭窄的敏感性为94.1%(32/34)、特异性为96.2% (154/160),显示闭塞的敏感性为94.7%(36/38)、特异性为98.7% (154/156);CE-MRA显示正常及轻度狭窄的敏感性为95.9%(117/122)、特异性为100% (72/72),显示明显狭窄的敏感性为91.2%(31/34)、特异性为95.6% (153/160),显示闭塞的敏感性为94.7%(36/38)、特异性为98.1%(153/156).结论 TWIST MRA操作简便,无静脉污染,一次检查不仅能准确显示小腿动脉病变,而且能提供反映疾病程度的功能学信息.

Abstract：

Objective To explore the value of time-resolved angiography with interleaved stochastic trajectories (TWIST)in providing hemodynamic indices and morphological imaging of calf arteries in patients with peripheral arterial occlusive disease(PAOD) with 3.0 T MR scanner. Methods Forty patients with confirmed or suspected PAOD underwent TWIST MRA for the calf arteries and conventional contrast-enhanced MRA(CE-MRA) for the whole lower peripheral arteries. TWIST MRA data were used to determine the bolus arriving time of the popliteal artery, the time difference of the bolus arrival in the popliteal artery between the two legs, calf artery transit time, and the mean peak enhancement time of calf arteries. The mean value of peak enhancement time of calf arteries was correlated with ankle-brachial index(ABI). The calf arteries were divided into 13 segments. The visible score of arterial segment was recorded, and the degree of arterial stenosis was graded too. In 16 patients, DSA was used as the gold standard to evaluate the sensitivity and specificity of TWIST MRA and CE-MRA. Results The bolus arriving time of the popliteal artery was (0.7±7.6) s the time difference of the bolus arrival in the popliteal artery between the two legs was (2.1±2.5) s, the calf artery transit time was (35.6±16.9) s, the mean value of peak enhancement time of calf arteries was (52.6±17.6) s. ABI was acquired from 24 patients and 48 legs, which correlated well with the mean value of peak enhancement time in calf arteries (r＝0.627,P＜0.01). The mean visible score was (2.83±0.48) of TWIST MRA images and (2.78±0.43) of CE-MRA images. There was no significant difference between them (P＞0.05). On CE-MRA, there were 38 legs with varying degrees of early venous enhancement; in contrast, there was no venous contamination on TWIST MRA. The sensitivity and specificity of TWIST MRA were 96.7% (118/122) and 100.0% (72/72) in showing normal artery and mild stenosis, 94.1% (32/34) and 96.2% (154/160) in showing severe stenosis, and 94.7% (36/38) and 98.7% (154/156) in showing occlusion. The sensitivity and specificity of CE-MRA were 95.9% (117/122) and 100.0% (72/72) in showing normal artery and mild stenosis, 91.2% (31/34) and 95.6% (153/160) in showing severe stenosis, and 94.7% (36/38) and 98.1% (153/156) in showing occlusion. Conclusion TWIST MRA is a preferable choice for calf arterial occlusive disease, which provided nice morphological images and useful hemodynamic indices with simple operation.     

Intra-arterial MR-angiography on an open-bore MR-scanner compared to digital-subtraction angiography of the infra-popliteal runoff in patients with peripheral arterial occlusive disease

PURPOSE: To evaluate the diagnostic value of contrast-enhanced intra-arterial 3D-MR-angiography (IA-MRA) of the infra-popliteal arteries in an open-bore magnet. Number, severity of arterial lesions, and artefacts were compared to routinely performed intra-arterial digital-subtraction angiography (IA-DSA) in patients suffering from symptomatic peripheral arterial occlusive disease (PAOD). MATERIAL AND METHODS: Fifteen patients admitted for PAOD underwent percutaneous transluminal angioplasty (PTA) by IA-DSA. After PTA, IA-MRA of the infra-popliteal station was performed on an open-bore 1.5T MR-scanner applying a low dose intra-arterial contrast-enhanced 3D-gradient-echo-MRA with gadopentate dimeglumine. The reading was performed by three blinded readers distinguishing moderate (< or =50%), significant stenoses (51-99%) and vessel occlusions. Imaging artefacts were recorded and binary classified as not disturbing or compromising the observation of the arterial tree. RESULTS: Overall IA-DSA revealed 36 moderate stenoses (< or =50%), 38 significant stenoses (51-99%), and 10 vessel occlusions. For the detection of significant stenoses and occlusions, the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of IA-MRA were 96%, 83%, 88%, 94% and 90%. The only observed artefact was venous overlay in four stations. The readout was not hampered in any case. CONCLUSION: Intra-arterial contrast-enhanced 3D-gradient-echo-MRA on an open-bore MR-scanner offers an acceptable diagnostic accuracy in diagnosing peripheral arterial occlusive disease in the infra-popliteal region and correlates well with DSA.     

Whole‐heart contrast‐enhanced coronary magnetic resonance angiography using gradient echo interleaved EPI

Whole‐heart coronary MR angiography (MRA) is a promising method for detecting coronary artery disease. However, the imaging time is relatively long (on the order of 10–15 min). Such a long imaging time may result in patient discomfort and compromise the robustness of whole‐heart coronary MRA due to increased respiratory and cardiac motion artifacts. The goal of this study was to optimize a gradient echo interleaved echo planar imaging (GRE‐EPI) acquisition scheme for reducing the imaging time of contrast‐enhanced whole‐heart coronary MRA. Numerical simulations and phantom studies were used to optimize the GRE‐EPI sequence parameters. Healthy volunteers were scanned with both the proposed GRE‐EPI sequence and a 3D TrueFISP sequence for comparison purposes. Slow infusion (0.5 cc/sec) of Gd‐DTPA was used to enhance the signal‐to‐noise ratio (SNR) of the GRE‐EPI acquisition. Whole‐heart images with the GRE‐EPI technique were acquired with a true resolution of 1.0 × 1.1 × 2.0 mm³ in an average scan time of 4.7 ± 0.7 min with an average navigator efficiency of 44 ± 6%. The GRE‐EPI acquisition showed excellent delineation of all the major coronary arteries with scan time reduced by a factor of 2 compared with the TrueFISP acquisition. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.     

小腿加压3.0T MRA评估糖尿病下肢血管病变的价值探讨

目的 以DSA为金标准评价小腿加压法3.0 T 增强磁共振血管成像(CE-MRA)在糖尿病下肢血管病变的应用价值.方法 对61例2型糖尿病合并下肢血管病变患者进行双下肢MRA检查,患者平均病程(11.6±6.0)年.使用3.0 T CE-MRA,其中小腿袖带加压后成像者(即加压组)31例,常规成像者30例(即常规组),...     

Contrast-enhanced magnetic resonance angiography in peripheral arterial disease: improving image quality by automated image registration

In peripheral arterial disease, contrast-enhanced MR angiography (MRA) is a noninvasive imaging alternative for catheter-based digital subtraction angiography (DSA). In DSA, final images are generated by subtracting a native mask image from subsequent contrast-enhanced images. Image quality is routinely improved by digitally shifting the mask image prior to subtraction if the patient has moved during angiography. This study investigated whether such image registration may also help to improve the image quality of MRA. In all, 545 MRA examinations of pelvic and leg arteries in patients with symptoms of peripheral arterial disease were studied retrospectively. Standard nonregistered MRA was compared to automatically linear, affine, and warp registered MRA by visual analysis and by three image quality parameters, including vessel detection probability (VDP) of angiographic maximum intensity projections. Most MRA of pelvic and upper leg arteries showed good nonregistered image quality. However, the 15% of lower legs with a body shift of 1 mm or more had relatively low nonregistered image quality, which improved significantly with image registration (VDP gain more than 18%, P < 0.05). The visual analysis gave similar results. In conclusion, image registration can improve image quality of MRA in peripheral arterial disease, especially in the lower legs.