PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Angiography, Digital Subtraction”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

MDCT compared with digital subtraction angiography for assessment of lower extremity arterial occlusive disease: importance of reviewing cross-sectional images.

OBJECTIVE: The aim of our study was to evaluate the efficacy of MDCT angiography in the assessment of lower limb peripheral arterial occlusive disease. MATERIALS AND METHODS: Twenty-four patients (representing 27 cases) with symptomatic lower extremity peripheral arterial occlusive disease underwent both MDCT angiography and digital subtraction angiography of the aortoiliac and lower extremity arteries. For data analysis, the arterial system was divided into 10 segments. Each segment was classified as normal, mildly stenotic, moderately stenotic, severely stenotic, or occluded. In evaluating MDCT angiographic findings, cross-sectional images were mainly observed by scrolling. The diagnostic accuracy of MDCT angiography was determined, using digital subtraction angiography as the standard reference. The extent of calcification in each segment was also assessed on MDCT angiography and was classified as absent, mildly calcified, or severely calcified. RESULTS: Of the 480 segments studied, 470 were assessable on both digital subtraction angiography and MDCT angiography. On digital subtraction angiography, 142 stenoocclusive segments (20 mildly stenotic, 14 moderately stenotic, 25 severely stenotic, and 83 occluded) were detected. With regard to the detection of segments that had more than mild stenosis, the sensitivity, specificity, and accuracy of MDCT angiography were 99.2%, 99.1%, and 99.1%, respectively. In the 421 noncalcified and mildly calcified segments, the sensitivity, specificity, and accuracy of MDCT angiography for the detection of more-than-mild stenosis were 100%, 100%, and 100%, respectively. CONCLUSION: MDCT angiography is a reliable method for evaluating the aortoiliac and lower extremity arteries.

Adolescent↗

Anatomical variations of the carotid bifurcation: implications for digital subtraction angiography and ultrasonography.

Intravenous digital subtraction angiography was used to determine prospectively the positional variations of the common carotid bifurcation in 100 consecutive patients with clinically suspected arteriosclerotic disease. The most common position (97/200, 48.5%) of the external carotid artery was anteromedial to the internal carotid artery. Position of the external carotid artery anterolateral to the internal carotid artery was noted in 26/200 (13%) bifurcations, but this anatomical variant was more common on the right (21/100) than on the left (5/100) (p less than 0.01). Practical implications may be drawn from this study. For digital subtraction angiography, the left anterior oblique view has to be considered the projection of choice and the right common carotid bifurcation is less likely to be adequately displayed than the left one; for duplex ultrasonography, optimal visualization is obtained from a posterolateral orientation of the transducer.

Adult↗

Contrast materials with low iodine concentration and intra-arterial digital subtraction angiography.

Intra-arterial digital subtraction angiography was performed in 25 patients, using Iopamidol in three different iodine concentrations: 50, 75, and 100 mg I/ml and comparing the results obtained with each concentration. The following vessels were explored: the aortic arch, the common carotid artery, the internal and external carotid arteries and the vertebral artery. The contrastographic effect was satisfactory when lower iodine concentrations were used in very selective catheterizations while greater concentrations of iodine were needed in less selective procedures.

Adolescent↗

Evaluation of high resolution digital subtraction angiography in neuroradiology.

A digital subtraction angiography (DSA) system has been modified for capabilities of a 1024 x 1024 matrix with 10 bit depth. Spatial resolution was increased with expansion of the matrix, but contrast resolution was not increased as determined by phantom experiments. Smaller focal spots and magnification factors were also important for improvement of spatial resolution. Clinical evaluation using carotid, vertebral, and cervical DSA with intra-arterial contrast injections demonstrated that there was slight improvement in the image quality, but the final diagnosis and management of patients were not changed with the use of high resolution DSA. Further improvements in image quality of DSA will be accomplished by improvements of image intensifiers and use of smaller focal spots.

Angiography, Digital Subtraction↗

Traumatic carotid-cavernous fistula identified by three-dimensional digital subtraction angiography--technical note.

Conventional digital subtraction angiography (DSA) identified a right carotid-cavernous fistula (CCF). Three-dimensional DSA (3D-DSA) was used to evaluate the CCF before treatment. The 3D-DSA images showed the anatomical relationship of the parent artery and the veins, which was difficult to understand on conventional DSA. The endoscopic image revealed the fistula and cavernous sinus. The direction and location of the fistula could be confirmed. However, the size of the fistula significantly varied depending on the adjustment of the window thresholds, so the balloon size could not be selected based on the images. Catheterization and subsequent embolization of the cavernous sinus with a detachable balloon via the femoral artery was successfully accomplished by referring to the 3D-DSA images.

Angiography, Digital Subtraction↗

[Blood supply reestablishment of avascular necrosis of femoral head with digital subtraction angiography].

OBJECTIVE: To use digital subtraction angiography (DSA) to evaluate blood supply reestablishment after the treatment of the avascular necrosis of femoral head (ANFH) by using the vascularized iliac periosteum with deep iliac circumflex artery (DICA) and vein pedicle. METHODS: Seldinger method was used to puncture femoral artery interpate of 20 patients with pre and postoperative ANFH. 6.5 F Cobrn conduct was optionally used and put directly into DICA and then contrast medium, was injected for observation of blood vessel. RESULTS: Before operation, the position of DICA was found constant, 3 to 7 branches termity among the crest part of iliac bone. Three weekes after operation, DICA was found wider than that before operation, but the blood flow speed remained almost the same and its termity was distributed evenly inside the femoral head and looked like a bird's net. Three months after operation, the blood vessel was still wider, but blood flowed faster and its termity changed roundish, and the bird's net changed greatly and capillaries reached the subchoronal zone of femoral head. CONCLUSION: Blood flow was well reestablished after the treatment of ANFH by DSA. It can be easily checked with less damage, large liability, and clear picture.

Adult↗

[Digital subtraction angiography in oncologic diagnosis].

Digital subtraction angiography has become a safe, accurate and reproducible means of evaluating the vascular system. It offers the possibility of obtaining high quality vascular images at very low intravascular iodine concentrations. In oncology, digital subtraction angiography is performed in preoperative visualization of the vascular supply of tumours, in planning and control of liver-port-systems and evaluation of complications following radiation therapy or chemotherapeutic measures. DSA has widely replaced film angiography in vascular imaging.

Angiography↗

Aortoiliac and lower extremity arteries assessed with 16-detector row CT angiography: prospective comparison with digital subtraction angiography.

PURPOSE: To prospectively compare the accuracy of 16-detector row computed tomographic (CT) angiography with conventional digital subtraction angiography (DSA) as the reference standard in the assessment of aortoiliac and lower extremity arteries in patients with peripheral arterial disease. MATERIALS AND METHODS: This study was approved by the institutional review board, and informed consent was obtained. A total of 39 consecutive patients (27 men [mean age, 66 years] and 12 women [mean age, 64 years]) with peripheral arterial disease underwent both conventional DSA and 16-detector row CT angiography. For data analysis, the arterial vascular system was divided into 35 segments. A total of 1365 arterial segments were analyzed for arterial stenosis by two independent blinded readers using a four-point grading system (grade 1, <10% luminal narrowing; grade 2, 10%-49% luminal narrowing; grade 3, 50%-99% luminal narrowing; grade 4, occlusion). Interobserver agreements were calculated by using kappa statistics. A third independent blinded reader assessed possible reasons for disagreements between 16-detector row CT angiographic findings and conventional DSA findings. Effective radiation dose was calculated for both imaging modalities. RESULTS: Sixteen-detector row CT angiographic and conventional DSA findings were diagnostic in all vascular segments. Compared with conventional DSA, the sensitivity and specificity of 16-detector row CT angiography with regard to detection of hemodynamically significant stenosis in all 35 arterial segments were 96% and 97%, respectively, for both readers. Readers 1 and 2 overestimated arterial stenosis in 42 (3%) and 34 (2%) arterial segments, respectively, and underestimated arterial stenosis in 13 (1%) and 10 (1%) arterial segments, respectively. Interobserver agreement was excellent (kappa = 0.84-1.00). Presence of anteroposteriorly located luminal narrowing and extensive vascular wall calcification were considered main reasons for disagreements between imaging modalities. Effective radiation dose was lower for 16-detector row CT angiography (1.6-3.9 mSv) than for conventional DSA (6.4-16.0 mSv). CONCLUSION: Sixteen-detector row CT angiography is an accurate and reliable noninvasive alternative to conventional DSA in the assessment of aortoiliac and lower extremity arteries in patients with peripheral arterial disease.

Adult↗

Optimization of beam parameters for dual-energy digital subtraction angiography.

Dual-energy digital subtraction angiography (DSA) is immune to the misregistration artifacts which plague conventional temporal subtraction DSA. However, since the signal-to-noise ratio (SNR) of dual-energy DSA is lower than temporal subtraction it is important to optimize the dual-energy technique with respect to the SNR. This study investigates the optimization of x-ray exposure parameters for the low- and high-energy x-ray beams, drawing upon our experience with dual-energy DSA studies in 20 cardiac patients. It is shown that the SNR is optimized, with respect to patient exposure, when the image intensifier (II) exposure for the high-energy beam is approximately 5 times higher than the low-energy beam. The unequal distribution of exposure between the low- and high-energy beams is achieved by selecting different video apertures for the two beams, and is therefore referred to as the "dual-aperture" technique. The dual-aperture technique achieves the same SNR as the single-aperture technique (which uses equal II exposures for the two beams) with 45% less patient exposure. In addition, the dual-aperture technique enhances the ability to maintain an optimum low-energy kVp, which increases the dual-energy signal amplitude. The optimum high-beam filter thickness for use with the dual-aperture approach is determined. The optimum filter thickness, which is dependent upon the desired tube loading, is found to range from 1.3 to 2.0 mm Cu for tube loads ranging from 188 to 688 J/beam pair.

Adult↗

Digital subtraction angiography of the left ventricle.

Twenty-eight patients have been studied by left ventricular angiography and digital subtraction angiography, using either a peripheral venous injection (16) or a central venous injection (12) of contrast medium. Digital subtraction angiography compared favourably to angiography in the qualitative assessment of left ventricular size and function. Measurement of ejection fraction demonstrated a good correlation (r = 0.83) between digital subtraction angiography and left ventricular angiography. In the assessment of left ventricular segmental wall motion the use of a central venous injection, particularly in those patients with severely impaired ventricular function, proved superior to the use of a peripheral injection.

Coronary Disease↗

Determination of left ventricular systolic wall thickness by digital subtraction angiography.

The accuracy of digital subtraction angiography (DSA) for determination of left ventricular (LV) systolic wall thickness and muscle mass was evaluated in 20 patients (mean age 50 +/- 11 years). Conventional LV angiograms were digitized and subtracted using a combined subtraction mode ('mask mode' and 'time interval difference' subtraction). Wall thickness and muscle mass were determined at end-diastole, after the first- and second-third of systole and at end-systole. M-mode echocardiography (Echo), which was obtained from beam selection of the two-dimensional echocardiogram and conventional angiography (LVA), served as reference techniques. Angiographic LV wall thickness and muscle mass were determined according to the technique of Rackley in both, right (RAO) and left (LAO) anterior oblique projections, whereas echocardiographic wall thickness was measured just below the mitral valve orthogonal to the posterior wall (= LAO equivalent). Percent wall thickening was calculated in all patients. LV end-diastolic wall thickness and muscle mass correlated well between DSA and LVA (LV end-diastolic wall thickness in LAO projection r = 0.72, biplane LV end-diastolic muscle mass r = 0.83), LV end-systolic wall thickness (1.44 vs 1.33 cm, P less than 0.05) and percent wall thickening (52 vs 42%, P less than 0.05) compared favourably between echocardiography and DSA but was significantly larger when echocardiographically measured than with DSA (LAO projection). DSA and echocardiography showed a good correlation in regard to LV end-diastolic and end-systolic wall thickness (correlation coefficient r = 0.89, standard error of estimate SEE = 0.15 cm or 13% of the mean value).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Comparison of spiral CT angiography with conventional digital subtraction angiography in the evaluation of renal transplant donors: a pilot study.

Conventional digital subtraction renal arteriography (IA-DSA) has been traditionally used as the preoperative imaging modality for assessment of renal vascular anatomy for renal transplant donors. This study evaluates the potential use of spiral CT angiography in replacing IA-DSA in the preoperative assessment of this group of patients. Seven patients underwent both spiral CT angiography and IA-DSA between October 1997 and April 1998. It is concluded that spiral CT angiography can demonstrate the number, length and location of renal arteries and it is suggested that spiral CT angiography can potentially replace IA-DSA in the preoperative assessment of renal donors.

Adult↗

MR angiography at 3T versus digital subtraction angiography in the follow-up of intracranial aneurysms treated with detachable coils.

BACKGROUND AND PURPOSE: Digital subtraction angiography (DSA) is used to follow-up intracranial aneurysms treated with detachable coils to identify recurrence and determine need for additional treatment. However, DSA is invasive and involves a small risk of neurologic complications. We assessed the feasibility and usefulness of 3D time-of-flight (TOF) MR angiography (MRA) performed at 3T compared with DSA for the follow-up of coil-treated intracranial aneurysms. METHODS: In a prospective study, 20 consecutive patients with 21 intracranial aneurysms treated with coils underwent DSA and nonenhanced and enhanced multiple overlapping thin-slab acquisition 3D TOF MRA at 3T on the same day at a mean follow-up of 6 months (range, 4-14 months) after coil placement. MRA images were evaluated for presence of artifacts, presence and size of aneurysm remnants and recurrences, patency of parent and branch vessels, and added value of contrast material enhancement. MRA and DSA findings were compared. RESULTS: Interobserver agreement of MRA was good, as was agreement between MRA and DSA. All three recurrences that needed additional treatment were detected with MRA. Minor disagreement occurred in four cases: three coil-treated aneurysms were scored on MRA images as having a small remnant, whereas on DSA images these aneurysms were occluded; the other aneurysm was scored on MRA images as having a small remnant, whereas on DSA images this was a small recurrence. Use of contrast material had no additional value. Coil-related MR imaging artifacts were minimal and did not interfere with evaluation of the occlusion status of the aneurysm. CONCLUSION: High-spatial-resolution 3D TOF MRA at 3T is feasible and useful in the follow-up of patients with intracranial aneurysms treated with coil placement.

Adolescent↗

Assessing cardiac anatomy with digital subtraction angiography.

The use of intravenous digital subtraction angiography in the assessment of patients with congenital heart disease is described. Intravenous digital subtraction angiographic techniques are particularly helpful in visually assessing left to right shunts in patients with atrial and ventricular septal defects and anomalies of pulmonary venous return. Digital subtraction angiographic techniques have also been used to quantitate the magnitude of left to right shunts and have been compared with radionuclide-determined pulmonary flow/systemic flow ratios (r = 0.89, p less than 0.0001). Digital subtraction angiographic techniques are particularly helpful in evaluating the right atrium, right ventricle and pulmonary arteries as well as the aorta and aortic arch. We have used digital subtraction angiographic techniques in the immediate and long-term postoperative evaluations of patients after congenital heart surgery. The safety of digital subtraction angiography lends itself to pediatric patients and can be performed on an out patient basis. Digital subtraction angiography provides significant anatomic information that has modified our traditional approach to patients with congenital heart disease.

Adolescent↗

[Diagnostic significance of intravenous digital subtraction angiography of the supra-aortic extracranial vascular system. Comparative study of i.v. DSA and plain film angiography].

Digital intravenous subtraction angiography (DSA) and conventional film angiography were used to evaluate the diagnostic reliability of DSA-examinations. In 90% of 650 DSA-angiogramms the image quality was diagnostic. For 124 carotid angiographies a comparison of both methods was possible and gave a sensitivity of 87%, a specificity of 96% and an accuracy of 90% for the DSA examinations. The authors believe that digital subtraction angiography is suitable as a screening method for supraaortal vascular occlusive diseases.

Aged↗

Distal lower extremity arteries: evaluation with two-dimensional MR digital subtraction angiography.

PURPOSE: To test the hypothesis that magnetic resonance (MR) digital subtraction angiography is superior to two-dimensional time-of-flight (TOF) MR angiography for demonstration of patent arteries in the distal lower extremity. MATERIALS AND METHODS: Thirty-seven lower extremities in 23 consecutive patients were imaged with two-dimensional TOF MR angiography and two-dimensional MR digital subtraction angiography. Images were interpreted in a randomized and blinded manner. Each lower extremity was subdivided into seven potential arterial segments. The number of digital arteries visualized was also determined. Overall image quality of MR digital subtraction and TOF angiograms was compared. The relative ability of MR digital subtraction angiography and TOF MR angiography to demonstrate patent arterial segments was assessed. RESULTS: MR digital subtraction angiography was significantly superior to TOF MR angiography for demonstration of patent arterial segments and digital arteries (P < .001). MR digital subtraction angiographic images were qualitatively superior to TOF images (P < .001). CONCLUSION: Two-dimensional MR digital subtraction angiography is superior to two-dimensional TOF MR angiography for help in identifying patent segments in the distal lower extremity.

Adult↗

Hemodynamic significance of renal artery stenosis: digital subtraction angiography versus systolically gated three-dimensional phase-contrast MR angiography.

PURPOSE: To compare digital subtraction angiography with three-dimensional phase-contrast magnetic resonance (MR) angiography in detection of significant renal artery stenosis. MATERIALS AND METHODS: Sixteen patients underwent digital subtraction angiography and systolically gated three-dimensional phase-contrast MR angiography within 1 week. Scoring of stenosis on MR angiograms was based on presence and length of a flow void and quality of flow signal intensity in the distal part of the artery. Intraarterial pressure measurement was the reference standard for hemodynamically significant renal artery stenosis. RESULTS: MR angiography depicted two of five patent accessory arteries. Comparison of digital subtraction angiography and MR angiography with intraarterial pressure measurements was possible in 25 main renal arteries. In 13 arteries, a pressure gradient of more than 15 mm Hg was found. Digital subtraction angiography depicted 10 of these stenoses (sensitivity, 77%; specificity, 92%). A flow void was present at MR angiography in eight stenoses (sensitivity, 62%; specificity, 83%). In 12 of the stenosed vessels, distal flow signal intensity was impaired at MR angiography (sensitivity, 92%; specificity, 75%). There was no difference between the two modalities (P > .05) in grading hemodynamic significance of renal artery stenosis. CONCLUSION: Systolically gated MR angiography and digital subtraction angiography are equally effective in depicting hemodynamically significant stenoses in the main renal arteries. MR angiography, however, is not adequate in depiction of accessory renal arteries.

Adult↗