Digital subtraction angiography of the renal arteries. Prospective comparison with conventional arteriography

Intravenous digital subtraction angiography (IV-DSA) of the aorta and renal arteries was compared with conventional arteriography of 40 patients with 92 renal arteries. Inadequate visualization of the vessel occurred in six renal arteries (6.5%). In arteries adequately imaged, for the evaluation of renal artery stenosis, the sensitivity of IV-DSA was 87.5% (28/32), the specificity 100% (54/54), and the accuracy 95.3% (82/86). Overall, accurate IV-DSA was obtained in 89.1% (82/92) of renal arteries and 85% (34/40) of the patients. IV-DSA is an accurate screening procedure for renal artery stenosis.     

Comparison of intravenous digital subtraction angiography to conventional aortography in patients with abdominal aortic aneurysm

Evaluation of intravenous digital subtraction angiography (IV DSA) in patients with abdominal aortic aneurysm was performed by obtaining catheter aortograms immediately before DSA studies in ten patients. Diagnostic images were obtained in nine of ten digital subtraction examinations. Although repeat injections were necessary in six DSA and three conventional aortography cases for adequate imaging of both cephalad and caudal extension of the aneurysm, average contrast dose was 53 cc (62 cc in standard catheter studies). Renal artery stenosis was diagnosed by DSA in two of three vessels, multiple renal arteries were demonstrated by both modalities in two cases. Digital subtraction and conventional aortographic findings were proved at surgery. Intravenous DSA was shown to be useful in the preoperative evaluation of patients with abdominal aortic aneurysm. This work was supported in part by U.S. Public Health Service Grant No. HL07334.     

Gadobenate dimeglumine-enhanced MR angiography of the abdominal aorta and renal arteries

OBJECTIVE: This study was conducted to determine the efficacy and safety of four different doses of gadobenate dimeglumine for contrast-enhanced three-dimensional MR angiography of the abdominal aorta and renal arteries. SUBJECTS AND METHODS: Ninety-four patients with suspected abnormality of the abdominal aorta or renal arteries underwent unenhanced three-dimensional gradient-recalled echo time-of-flight MR angiography and contrast-enhanced MR angiography after the IV injection of one of four doses of gadobenate dimeglumine (0.025, 0.05, 0.1, and 0.2 mmol/kg of body weight). Efficacy was assessed on-site and by two blinded off-site reviewers in terms of change in total diagnostic quality score and diagnostic quality score per vessel segment from baseline unenhanced time-of-flight MR angiography to contrast-enhanced MR angiography. Secondary efficacy end points included lesion count and level of confidence in lesion characterization. Safety assessments comprised adverse event monitoring, physical evaluation, vital signs, ECG, and laboratory investigations. RESULTS: A significant change in the total diagnostic quality score from unenhanced to contrast-enhanced MR angiography was observed at all doses. The change increased with increased dose, plateauing at the 0.1 mmol/kg dose level. More patients with lesions detected and increased reviewer confidence for lesion characterization were noted on contrast-enhanced MR angiography compared with unenhanced MR angiography, although no dose-related trends were observed. All doses were well tolerated, and no significant changes in safety parameters were observed. CONCLUSION: Gadobenate dimeglumine is an effective and safe agent for contrast-enhanced MR angiography of the abdominal aorta and renal arteries. A dose of 0.1 mmol/kg of body weight appears to be the most suitable.     

Fibromuscular dysplasia of renal arteries: comparison of intravenous digital subtraction angiography with conventional angiography

Intravenous digital subtraction angiography (IV-DSA) was compared with conventional arteriography (CA) in 14 patients with fibromuscular dysplasia (FMD) of at least one renal artery. IV-DSA identified 29 of the 34 renal arteries detected by CA. A diagnostic quality IV-DSA examination was obtained in 23 of 29 renal arteries (78%). In adequately imaged renal arteries, IV-DSA correctly identified 12 of 20 FMD renal arteries, misdiagnosed 8 FMD renal arteries as normal and correctly identified 3 normal renal arteries. These poor results, due to poor spatial resolution and subtraction artifacts inherent in the IV-DSA system, warrant careful interpretation of negative examinations and further evaluation of high risk patients.     

Digital subtraction angiography of the thoracic aorta

Forty-three patients with acquired and congenital abnormalities of the thoracic aorta were studied using digital subtraction angiography (DSA) after an intravenous bolus injection of 40 ml of contrast material. Abnormalities studied included coarctation, pseudocoarctation, Marfan syndrome, cervical aorta, double aortic arch, aneurysm, dissection, and tumor. Twenty-four patients also had conventional angiography. DSA was accurate in 95% of cases; in the other 5%, involving patients with acute type I dissection, the coronary arteries could not be seen. The authors concluded that in 92% of their patients, DSA could have replaced the standard aortogram.     

Assessment of aortoiliac and renal arteries: MR angiography with parallel acquisition versus conventional MR angiography and digital subtraction angiography

PURPOSE: To prospectively compare the image quality, sensitivity, and specificity of three-dimensional gadolinium-enhanced magnetic resonance (MR) angiography accelerated by parallel acquisition (ie, fast MR angiography) with MR angiography not accelerated by parallel acquisition (ie, conventional MR angiography) for assessment of aortoiliac and renal arteries, with digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: The study was approved by the institutional review board; informed consent was obtained from all patients. Forty consecutive patients (33 men, seven women; mean age, 63 years) suspected of having aortoiliac and renal arterial stenoses and thus examined with DSA underwent both fast (mean imaging time, 17 seconds) and conventional (mean imaging time, 29 seconds) MR angiography. The arterial tree was divided into segments for image analysis. Two readers independently evaluated all MR angiograms for image quality, presence of arterial stenosis, and renal arterial variants. Image quality, sensitivity, and specificity were analyzed on per-patient and per-segment bases for multiple comparisons (with Bonferroni correction) and for dependencies between segments (with patient as the primary sample unit). Interobserver agreement was evaluated by using kappa statistics. RESULTS: Overall, the image quality with fast MR angiography was significantly better (P=.001) than that with conventional MR angiography. At per-segment analysis, the image quality of fast MR angiograms of the distal renal artery tended to be better than that of conventional MR angiograms of these vessels. Differences in sensitivity for the detection of arterial stenosis between the two MR angiography techniques were not significant for either reader. Interobserver agreement in the detection of variant renal artery anatomy was excellent with both conventional and fast MR angiography (kappa=1.00). CONCLUSION: Fast MR angiography and conventional MR angiography do not differ significantly in terms of arterial stenosis grading or renal arterial variant detection.     

腹主动脉、髂动脉及下肢动脉的MR数字减影血管造影

目的探讨增强ＭＲ血管造影的方法,评价快速梯度回波序列增强ＭＲ数字减影血管造影对腹主动脉、髂动脉及下肢动脉病变的诊断价值。方法３６例临床疑有腹主动脉、髂动脉或下肢动脉疾病的病人进行增强３Ｄ快速梯度回波扫描（重复时间１２或２０毫秒、回波时间４或５毫秒、反转角６０°）。对比剂用量０．２ｍｍｏｌ／ｋｇ。原始图像先进行减影处理,再进行最大信号强度投影（ＭＩＰ）重建。结果所有３６例患者（包括６例正常）均满意地显示了感兴趣区的血管。其中,腹主动脉夹层动脉瘤４例,肾动脉狭窄２例,人工血管移植术３例,腹主动脉瘤２例,髂动静脉瘘１例,髂动脉及下肢动脉狭窄１８例。结论三维磁共振数字减影血管造影是腹部及外周血管成像可靠的、充满活力的方法。     

Intravenous digital subtraction angiography of the thoracic and abdominal aorta

Intravenous digital subtraction angiography (IV DSA) is a new imaging modality that utilizes techniques of video image acquisition and computer image manipulation to provide anatomic information about blood vessels and organs. In many ways, it represents an electronic version of classic intravenous and film-subtraction angiography. As a means of imaging the thoracic and abdominal aorta, IV DSA has demonstrated great potential, particularly in vessels originally imaged by the former techniques. We have imaged the aorta in over 300 cases at Brigham and Women's Hospital, either alone, or in combination with other vessels in the course of work-up for vascular disease. Although experience has been limited, intravenous imaging of the aorta can be routinely performed, providing reliable and clinically significant information. Supported in part by CV Training Grant 201-HL20895-06     

Digital subtraction angiography of the abdominal aorta and lower extremities: carbon dioxide versus iodinated contrast material.

PURPOSE: To compare the diagnostic value of carbon dioxide to that of iodinated contrast material for digital subtraction angiography of the abdominal aorta and lower extremities. MATERIALS AND METHODS: Thirty-five patients underwent comparative CO2 and iodinated contrast material arteriography of the abdominal aorta and lower extremities. For each contrast study, three independent observers evaluated the degree of opacification and percentage of stenosis of each vessel, the degree of certainty of their observations, and the overall quality of the study. Data of CO2 and iodinated studies were compared using analysis of variance for repeated measures. Interobserver and intertechnique agreements were estimated with Cohen's kappa and intraclass correlation coefficient. RESULTS: Iodine-based vascular opacification was superior to that with CO2 in the central and distal arteries (P = .02). The degree of certainty and overall quality score were higher for iodine than for CO2-based contrast studies (P = .00001). The interobserver agreement for categorizing stenoses was higher for iodine as compared to CO2-based angiography. No significant difference was observed between the mean stenosis values obtained with CO2 and iodine-based angiography in any segment. Intraclass correlation coefficient demonstrated a high degree of convergence of the two techniques for assessing the percentage of stenosis. CONCLUSION: CO2 can be used as an alternative to iodinated contrast material for obtaining arteriograms of the abdominal aorta and lower extremities for investigating atherosclerotic disease.     

Contrast-enhanced,k-space-centered,breath-hold MR angiography of the renal arteries and the abdominal aorta

The purpose of this study was to evaluate the capability of contrast-enhanced breath-hold fast imaging with steady-state precession (FISP) three-dimensional MR angiography (MRA) to detect stenotic lesions of the abdominal aorta, the renal arteries, and the iliac arteries by using a k-space-centered 20-ml gadolinium-diethylene pentaacetic acid (Gd-DTPA) bolus. Fifty patients were studied before conventional x-ray angiography. Contrast-enhanced breath-hold FISP three-dimensional MRA was applied in the coronal view, centered at the renal arteries. Twenty ml of Gd-DTPA was used in all subjects. A test bolus was applied to determine the injection time for the k-space-centered bolus injection. Of 300 segments, 284 segments were classified correctly, 11 were overestimated, and five were underestimated. Sensitivity was 98%, specificity was 96%, positive predictive value was 96%, negative predictive value was 98%, and accuracy was 97%. Of the 50 patients studied, 43 were staged correctly. No venous overlay was seen in 31 patients; partial overlay was seen in 16 patients, and venous structure overlay obscuring arterial anatomy was found in two patients. Six of nine accessory renal arteries could be identified by MRA. Intraobserver variability was .94. This study has shown the ability of contrast-enhanced breath-hold FISP three-dimensional MRA to detect and grade vascular lesions in the abdominal aorta and the renal arteries. The method may serve as a screening tool in the future.     

Digital subtraction cerebral angiography by intraarterial injection: comparison with conventional angiography

For 4 months, a prototype digital subtraction system was used to obtain images of the cerebral vasculature after intraarterial contrast injections. In 12 instances, the intraarterial injections were recorded with both a digital subtraction unit and conventional direct magnification film-screen system. The digital subtraction and conventional film subtraction images were compared and graded for quality and information content by three skilled observers. In addition, quantitative measurements of contrast-detail performance and spatial resolution were obtained on both the digital system and the screen-film imaging chain. In a clinical setting, both the digital subtraction and conventional film-screen systems provided similar quality images and angiographic information. Contrast-detail curves demonstrated that digital subtraction angiography outperformed conventional film technique for low-contrast objects. Digital subtraction angiography also reduced the time required to obtain the angiogram, markedly reduced film cost, and lowered the contrast agent burden.     

Digital subtraction angiography of the arteries of the head and neck

The advantages and disadvantages of intravenous and intra-arterial digital subtraction angiography of the arteries of the head and neck are discussed. The clinical applications of the two techniques are compared.     

Intravenous digital subtraction angiography of the precerebral and cerebral arteries in patients with TIA. A comparison with conventional angiography

A study of the diagnostic utility of both intravenous digital subtraction angiography (IV-DSA) and conventional angiography of precerebral and cerebral arteries is presented. The series comprised 60 patients with TIA, who underwent the two procedures with a mean interval of 16 days. Conventional angiography was generally superior to IV-DSA, and this was particularly marked in the siphons and cerebral arteries. Only the excellent IV-DSA examinations obtained in a few patients with TIA could be accepted as final pre-operative procedures. Accurate imaging of the lesions and collateral flow pattern usually required intra-arterial injections, and intra-arterial DSA is now usually preferred.     

Digital subtraction angiography in renal transplant recipients

The renal transplant vascularity of 72 patients was investigated by intravenous digital subtraction angiography (IV DSA). The procedure was combined with selective venous renin sampling of the transplant and native kidneys to identify the source of hypertension in these patients. Abnormalities were found on IV DSA examination in 26 patients, of whom 7 had graft artery stenosis, 7 had diffuse intrarenal narrowing, 9 had lower pole ischemia, and 3 had aneurysmal dilatation. The combined outpatient procedure was well tolerated by all patients with no complications nor incidence of proteinuria.     

Imaging of the digital arteries: digital subtraction angiography versus conventional arteriography

A retrospective study of 95 patients was undertaken to compare digital subtraction angiography (DSA) and conventional arteriography of the hand. Eighty patients had conventional angiography and 15 had DSA. In comparison with conventional angiography, DSA is more cost-efficient and facilitates outpatient angiography. It provides images as acceptable as those of conventional angiography. We conclude that intra-arterial DSA is now the procedure of choice for angiographic mapping of the digital arteries.