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ABSTRACT: One pillar of Model-Driven Development of real-time software is the separation of concerns between application model and target platform. This requires the definition of model transformations realizing the mapping of the application model onto the target platform. However, target platforms APIs and implementation patterns vary largely from one to the other. This requires the development of several dedicated model transformations which actually embed a given computing target platform model. Dedicated model transformations have shown their limits as soon as we want to modify target platform. In this context, a good compromise could be to extract implementation patterns from model transformation and encapsulate them in a platform model. We, therefore propose some modeling heuristics that permits to build detailed descriptions of the target execution platform, where all platform-specific implementation choices are made explicit using a small set of variation points specific to real-time multi-tasking applications. The benefit expected is a true separation of concerns enabling efficient, reusable and portable transformation processes.
Software Engineering Conference (APSEC), 2010 17th Asia Pacific; 01/2011
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ABSTRACT: Multi-threaded real-time applications run on platforms that offer services such as concurrency, timing and synchronization. In a model driven context, separation of concerns between functional specification and design choices is one of the key challenges. For that purpose, annotations defined by the MARTE sub-profile for software resource modeling (SRM) provide high level abstractions of target software platforms helping to deploy the same application model on various targets. However, deployment of an application on a platform is not only characterized by the API of the targeted OS, but it is also influenced by possible design restrictions set by the programming languages and their related libraries. We examine key characteristics that exist in two widely used programming languages (C++ and Java) and their libraries to analyze how this can be handled with an MDE approach based on the use of SRM.
Engineering of Complex Computer Systems, 2009 14th IEEE International Conference on; 07/2009
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L. Arnaud,
D. Galpin,
S. Chhun,
C. Monget,
E. Richard,
D. Roy,
C. Besset,
M. Vilmay,
L. Doyen,
P. Waltz,
E. Petitprez, F. Terrier,
G. Imbert,
Y. Le Friec
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ABSTRACT: This work analyses electromigration and dielectric lifetimes of 45 nm node CMOS interconnects. Reliability mechanisms and failure modes are discussed considering, on one hand, the interconnect materials and processes steps, and on the other hand scaling issues. Robust reliability performance meeting the required products target is actually obtained with process integration schemes used for the 45 nm node thanks to fine optimizations of Cu barriers, Cu filling, and ULK surface quality.
Interconnect Technology Conference, 2009. IITC 2009. IEEE International; 07/2009
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R. Passerone,
W. Damm,
I. Ben Hafaiedh,
S. Graf,
A. Ferrari,
L. Mangeruca,
A. Benveniste,
B. Josko,
T. Peikenkamp,
D. Cancila,
A. Cuccuru,
S. Gerard, F. Terrier,
A. Sangiovanni-Vincentelli
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ABSTRACT: This article provides an overview of current efforts in Europe for using metamodeling in the integrated development of critical systems such as automotive electronics. It distinguishes between lightweight versus heavyweight approaches, surveys a number of related current European projects, and gives details about the Speeds project to illustrate the role of metamodeling-driven system engineering.
IEEE Design and Test of Computers 07/2009; · 1.39 Impact Factor
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ABSTRACT: The aim of this study was to refine the description of the renal function based on MR images and through transit-time curve analysis on a normal population and on a population with renal failure, using the quantitative model of the up-slope. Thirty patients referred for a kidney MR exam were divided in a first population with well-functioning kidneys and in a second population with renal failure from ischaemic kidney disease. The perfusion sequence consisted of an intravenous injection of Gd-DTPA and of a fast GRE sequence T1-TFE with 90 degrees magnetisation preparation (Intera 1.5 T MR System, Philips Medical System). To convert the signal intensity into 1/T1, which is proportional to the contrast media concentration, a flow-corrected calibration procedure was used. Following segmentation of regions of interest in the cortex and medulla of the kidney and in the abdominal aorta, outflow curves were obtained and filtered to remove the high frequency fluctuations. The model of the up-slope method was then applied. Significant reduction of the cortical perfusion (Qc = 0.057+/-0.030 ml/(s 100 g) to Qc = 0.030 +/- 0.017 ml/(s 100 g), P < 0.013) of the medullary perfusion (Qm = 0.023 +/- 0.018 ml/(s 100 g) to Qm = 0.011 +/- 0.006 ml/(s 100 g), P < 0.046) and of the accumulation of contrast media in the medulla (Qa = 0.005 +/- 0.003 ml/(s 100 g) to Qa = 0.0009 +/- 0.0008 ml/(s 100 g), P < 0.001) were found in presence of renal failure. High correlations were found between the creatinine level and the accumulation Qa in the medulla (r2 = 0.72, P < 0.05), and between the perfusion ratio Qc/Qm and the accumulation Qa in the medulla (r2 = 0.81, P < 0.05). No significant difference was found in times to peak between both populations despite a trend showing Ta the time to the end of the increasing contrast accumulation period in the medulla, arriving later for renal failure. Advances in MR signal calibration with the building of quantitative model such as the up-slope allow to assess kinetic and haemodynamic and functional parameters of the diseased kidney.
European Journal of Radiology 04/2005; 54(1):124-35. · 2.61 Impact Factor
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K O Lövblad,
S G Wetzel,
T Somon,
K Wilhelm,
A Mehdizade,
A Kelekis,
M El-Koussy,
S El-Tatawy,
M Bishof,
G Schroth,
S Perrig,
F Lazeyras,
R Sztajzel, F Terrier,
D Rüfenacht,
J Delavelle
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ABSTRACT: We carried out MRI on 16 male and three female comatose patients, aged 2 days to 79 years, with suspected cortical ischaemia referred from our intensive care units. Using a head coil, and following standard imaging, including coronal fluid-attenuated inversion-recovery images, we performed diffusion-weighted imaging (DWI) using a whole-brain multislice single-shot echo-planar sequence with b 0 and 1000 s/mm2: 5-mm slices covering the whole brain, TR 7000 TE 106 ms, 128 x 128 pixels, field of view 250 mm, one excitation. Maps of apparent diffusion coefficients (ADC) were generated automatically. DWI showed cortical, basal ganglia and watershed-area high signal in all cases, associated with a decrease in ADC to 60- 80% of normal. DWI showed lesions not seen (40%) or underestimated (40%) on conventional T2-weighted imaging. Within 24 h of the onset of symptoms, DWI showed changes not readily detectable on T2-weighted images. The cortical high signal on DWI and the ADC changes, suggesting severe ischaemia rather than oedema, was found in areas known to be affected by cortical laminar necrosis. Extension to the brain stem and white matter was associated with a higher likelihood of death.
Neuroradiology 04/2004; 46(3):175-82. · 2.82 Impact Factor
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ABSTRACT: Haemophilic pseudotumour (HP) is a rare but very serious complication of haemophilia. HP affects mainly patients with severe haemophilia and those who have developed antibodies to factor VIII or factor IX. We report on a 45-year-old man with haemophilia A and high titres of inhibitors who developed an extensive HP with progressive destruction of the right ilium over a period of 12 years. The different therapeutic options (conservative management by replacement therapy, surgical approach, radiotherapy, percutaneous evacuation with secondary refilled cavity and transcatheter arterial embolization) are reviewed.
Skeletal Radiology 10/2002; 31(9):550-3. · 1.54 Impact Factor
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ABSTRACT: The aim of this study was to compare the performance of the CT and the water-soluble contrast enema (CE) in the diagnosis and the severity of acute left-colonic diverticulitis, and to recognize the impact of CT during the acute phase and after a first acute episode successfully treated medically. From 1986 to 1997, all patients admitted in our emergency center with clinically suspected left-colonic diverticulitis had a CE and a CT within 72 h of their admission, unless clinical findings required immediate laparotomy. They were prospectively included in the study if one or both radiological exams showed signs of acute diverticulitis and/or diverticulitis was surgically removed and histologically proven. Diverticulitis was considered moderate when CT showed localized thickening of the colonic wall (5 mm or more) and inflammation of pericolic fat and CE showed segmental lumen narrowing and tethered mucosa; it was considered severe when abscess and/or extraluminal air and/or contrast were observed on CT and when one or both of the latter signs were seen on CE. Five hundred forty-two patients entered the study; 465 patients (86%) had a CT exam, 439 (81%) had a CE, and 420 (77%) had both exams. The performance of CT is significantly superior to CE in terms of sensitivity (98 vs 92%, p<0.01), and in the evaluation of the severity of the inflammation (26 vs 9%, p<0.02). Moreover, of 69 patients who had an associated abscess seen on CT, only 20 (29%) had indirect signs of this complication on CE. During the acute phase the chances of medical treatment failure are statistically greater when diverticulitis is considered severe on CT than when it is considered moderate (26% for the severe diverticulitis vs 4% for the moderate ones, p<0.0001). After successful medical treatment of the acute episode, patients with severe diverticulitis on the CT had statistically greater incidence of secondary bad outcome than patients with moderate diverticulitis (36 vs 17%, p<0.0001). Computed tomography should be preferred to CE as the initial radiological exam of diverticulitis because of its statistically significant superiority in sensitivity and for its statistically much higher performance in the detection of severe infection, especially when an abscess is associated with the disease. The severity of diverticulitis on CT is statistically predictive of the risk of medical treatment failure during the acute phase and of the chances of bad secondary outcome after a successful medical treatment of the first episode.
European Radiology 05/2002; 12(5):1145-9. · 3.22 Impact Factor
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ABSTRACT: The aim of this study was to compare the performance of the CT and the water-soluble contrast enema (CE) in the diagnosis
and the severity of acute left-colonic diverticulitis, and to recognize the impact of CT during the acute phase and after
a first acute episode successfully treated medically. From 1986 to 1997, all patients admitted in our emergency center with
clinically suspected left-colonic diverticulitis had a CE and a CT within 72h of their admission, unless clinical findings
required immediate laparotomy. They were prospectively included in the study if one or both radiological exams showed signs
of acute diverticulitis and/or diverticulitis was surgically removed and histologically proven. Diverticulitis was considered
moderate when CT showed localized thickening of the colonic wall (5mm or more) and inflammation of pericolic fat and CE showed
segmental lumen narrowing and tethered mucosa; it was considered severe when abscess and/or extraluminal air and/or contrast
were observed on CT and when one or both of the latter signs were seen on CE. Five hundred forty-two patients entered the
study; 465 patients (86%) had a CT exam, 439 (81%) had a CE, and 420 (77%) had both exams. The performance of CT is significantly
superior to CE in terms of sensitivity (98 vs 92%, p<0.01), and in the evaluation of the severity of the inflammation (26 vs 9%, p<0.02). Moreover, of 69 patients who had an associated abscess seen on CT, only 20 (29%) had indirect signs of this complication
on CE. During the acute phase the chances of medical treatment failure are statistically greater when diverticulitis is considered
severe on CT than when it is considered moderate (26% for the severe diverticulitis vs 4% for the moderate ones, p<0.0001). After successful medical treatment of the acute episode, patients with severe diverticulitis on the CT had statistically
greater incidence of secondary bad outcome than patients with moderate diverticulitis (36 vs 17%, p<0.0001). Computed tomography should be preferred to CE as the initial radiological exam of diverticulitis because of its
statistically significant superiority in sensitivity and for its statistically much higher performance in the detection of
severe infection, especially when an abscess is associated with the disease. The severity of diverticulitis on CT is statistically
predictive of the risk of medical treatment failure during the acute phase and of the chances of bad secondary outcome after
a successful medical treatment of the first episode.
European Radiology 01/2002; 12(5):1145-1149. · 3.22 Impact Factor
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ABSTRACT: The aim of the present study was to assess the hypothesis that, when present in nasopharyngeal secretions, Streptococcus pneumoniae. Haemophilus influenzae, and Moraxella catarrhalis play a pathogenic role early in the course of an upper respiratory tract infection. Adults with a clinical diagnosis of acute sinusitis or common cold were enrolled. Participants were randomly assigned in a double-blind manner to receive azithromycin 500 mg daily or placebo for 3 days. The effect of treatment on symptom evolution in the predefined subset of patients with Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis in their nasopharyngeal secretions was assessed. Of 265 patients enrolled, 132 received placebo and 133 azithromycin. Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis was identified in nasopharyngeal secretions of 77 patients (29%). In this predefined subgroup of patients with Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis, resolution of symptoms by day 7 occurred in 73% of those treated with azithromycin compared with 47% of those who received placebo (P=0.007). The median time before resolution of symptoms was 5 days in the azithromycin group compared to 7 days in the placebo group. Respiratory complications requiring antibiotic treatment occurred in 19% of patients in the placebo group and in 3% of the azithromycin group (P=0.025). In the remaining 188 patients without Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis, resolution of symptoms by day 7 was similar in both groups (69% in the placebo group vs. 64% in the azithromycin group [P=0.75]). Antibiotic treatment is of clinical benefit for patients with acute sinusitis or common cold when Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis is present in nasopharyngeal secretions. This observation provides new insights into the pathogenic role of these bacteria in the early stage of the common cold.
European Journal of Clinical Microbiology 08/2001; 20(7):445-51. · 2.86 Impact Factor
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ABSTRACT: To evaluate the potential of an iron oxide-based MR contrast agent for the detection and delineation of experimental liver tumors during the early vascular phase of the compound.
Superparamagnetic blood pool agent (SBPA) was administered intravenously to rabbits bearing VX2 tumors. Images were acquired before the injection, immediately after, and 1 or 3 weeks later. The variations of signal intensity were measured in the tumors and in several tissues for various T1-weighted spin-echo, T2-weighted fast spin-echo, and T2-weighted gradient-recalled-echo sequences.
Fourteen and 12 of the 16 tumors were detected immediately after SBPA injection using, respectively, the T2-weighted fast spin-echo and T2-weighted gradient-recalled-echo sequences. A significant decrease in signal intensity was observed in well-perfused organs, and blood signal was abolished even at the lowest injected dose and using a T1-weighted sequence. In the late phase, the loss in signal intensity of the liver was even more pronounced.
The dominant T2 effect of SBPA induces an increase in the tumor-to-liver and tumor-to-blood contrast during the vascular phase, improving the detection of the tumors and allowing the distinction between small lesions and vessels through plane. This effect on the liver signal persists for several days because of the incorporation of SBPA in the reticuloendothelial system.
Investigative Radiology 02/2001; 36(1):15-21. · 4.59 Impact Factor
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ABSTRACT: To evaluate the accuracy of magnetic resonance (MR) sialography in detecting salivary glandular calculi and ductal stenoses.
In a prospective study, 64 salivary glands in 61 consecutive patients with acute or recurrent parotid or submandibular glandular swelling were examined by using three-dimensional (3D) extended-phase conjugate-symmetry rapid spin-echo (EXPRESS) MR imaging. Transverse and sagittal-oblique source images and maximum intensity projection images were obtained. All MR images were analyzed independently by two radiologists, without knowledge of the final diagnosis. The reference standard was conventional sialography, ultrasonography (US), and sialendoscopy with or without surgery in 31 glands and was conventional sialography and US in 33 glands.
Final diagnoses included sialolithiasis (n = 23), sialolithiasis and stenosis (n = 9), stenosis without lithiasis (n = 11), early Sjögren syndrome without ductal stenosis (n = 2), ductal displacement (n = 3), and normal salivary glands (n = 16). The sensitivity, specificity, and positive and negative predictive values of MR sialography to detect calculi were 91%, 94%-97%, 93%-97%, and 91%, respectively. False-negative readings occurred due to calculi with a diameter of 2-3 mm in nondilated salivary ducts. Ductal stenosis was assessed, with a sensitivity of 100%, specificity of 93%-98%, positive predictive value of 87%-95%, and negative predictive value of 100%. Interobserver agreement was very good (kappa = 0.85-0.97).
MR sialography with 3D EXPRESS imaging enables reliable prediction of salivary gland calculi and stenoses.
Radiology 12/2000; 217(2):347-58. · 5.73 Impact Factor
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ABSTRACT: The relationship between abnormalities found by magnetic resonance imaging (MRI) and proton spectroscopy (MRS) and the clinical signs of hepatic encephalopathy is not well characterized. Motor disturbances have been described, suggesting that basal ganglia (BG) are altered.
We evaluated 19 unselected consecutive patients with biopsy-proven cirrhosis evaluated for liver transplantation for the presence of parkinsonian signs using the Unified Parkinson's Disease Rating Scale (UPDRS) and Purdue Pegboard test, and correlated these neurologic abnormalities with MRI and MRS studies. Brain MRI intensities were expressed as signal-to-noise ratios. MRS findings obtained from one voxel in the BG and one in the occipital white matter (WM) were expressed as metabolite ratios. Six healthy subjects had normal values.
Compared with healthy subjects, patients with subclinical or grade 1 hepatic encephalopathy had hyperintensity in occipital WM and all BG tissues except thalamus and reduced Ino/Cr and Cho/Cr ratios in both voxels. In the BG, MRI intensity was correlated with the UPDRS (P < 0.05, r = 0.56). The Cho/Cr ratio also correlated with both UPDRS (P < 0.02, r = -0.59) and Pegboard scores (P < 0.02, r = 0.61).
In cirrhosis, parkinsonian signs correlate with BG alterations detected by MRI and MRS.
Gastroenterology 10/2000; 119(3):774-81. · 11.68 Impact Factor
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ABSTRACT: It is well established that ADP is an important regulator of the oxidative phosphorylation in the mitochondria. Thus, by means of noninvasive techniques it is demonstrated that the relationship between O(2) consumption of the human gastrocnemius at rest and its temperature is likely determined by at least two factors: 1) the modulation of the rate of the chemical reactions imposed by the "physical" temperature-effect; 2) the influence of temperature-induced ADP concentration changes ( approximately 0.83 microM degrees C(-1)) on oxidative phosphorylation. ADP was assessed by applying the temperature-corrected Lohmann equilibrium equation. PCr and ATP were found to increase, with decreasing temperature (-0.54+/-0.05 and -0.17+/-mM degrees C(-1), respectively), while pH varies following the alpha-stat hypothesis (-0.016+/-0.001 pH degrees C(-1)). These findings should be of value when dealing with muscle physiology in extreme environments or clinical applications of hypothermia.
Magnetic Resonance in Medicine 05/2000; 43(4):611-4. · 2.96 Impact Factor
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ABSTRACT: A minority of patients with common cold and upper respiratory tract infections have a bacterial infection and may benefit from antibiotic therapy. The present analysis set out to determine whether there were clinical symptoms or signs which could help the clinician to identify a subset of patients with moderate forms of acute rhinosinusitis who are infected with pathogenic bacteria. Detailed clinical history and medical examination were obtained from 265 patients (mean age 35 years, 138 females and 127 males) presenting symptoms of upper respiratory tract infections but no fever above 38 degrees C. The presence of three pathogenic bacteria (S. pneumoniae, H. influenzae or M. catarrhalis) was determined in all patients by culture of nasopharyngeal secretions. Aggravating factors for severity of rhinosinusitis, such as severe nasal obstruction, inferior and/or middle turbinate hypertrophy, oedema of the middle meatus mucosa and septal defects, were not associated with the presence of bacteria. Pathogenic bacteria were found in 77 patients (29%). The clinical signs and symptoms which were significantly associated in a multivariate model with the presence of bacteria included facial pain (p < 0.003), coloured nasal discharge (p < 0.003) and radiological maxillary sinusitis (complete opacity, air-fluid level or mucosal thickening greater than 10 mm) (p < 0.002). This, the best predictive model, had a sensitivity of 69% and a specificity of 64% and therefore could not be used either as a screening tool or as a diagnostic criterion for bacterial rhinosinusitis. We conclude that signs and symptoms of acute rhinosinusitis in patients with a mild to moderate clinical presentation are poor predictors of the presence of bacteria. In agreement with previous studies, culture of nasopharyngeal secretions may identify patients who would benefit from antibiotic treatment. Thus, antibiotic therapy should not be prescribed in the absence of bacteriological evidence.
Schweizerische medizinische Wochenschrift 02/2000; Suppl 125:27S-29S. · 1.68 Impact Factor
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ABSTRACT: The aim of this study was to demonstrate the feasibility of the absolute renal blood flow quantification using MRI and injection of contrast media. Using a T1-weighted fast gradient sequence following an intravenous bolus injection of Gd-DTPA, dynamic images of the kidney were obtained in patients with well-functioning native kidneys (n = 7) or transplant (n = 9), with significant renal artery stenosis (n = 4) and with renal failure (n = 7). After signal intensity calibration, the absolute renal perfusion was equal to the wash-in slope of the renal transit curve divided by the contrast medium concentration at the peak of the bolus in the aorta. The cortical blood flow was 2.54+/-1.16 ml/min per gram in well-functioning kidneys decreasing to 1.09+/-0.75 ml/min per gram in case of renal artery stenosis (p = 0.04) and to 0.51+/-0.34 ml/min per gram in case of renal failure (P<0.001). These measurements were in agreement with previous results obtained by other methods. A standard MRI imaging sequence and a simple model can provide realistic quantitative data on renal perfusion. This work justifies further studies to compare this model with a gold standard for renal blood flow measurements.
European Radiology 01/2000; 10(8):1245-52. · 3.22 Impact Factor
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ABSTRACT: To determine the influence of early pain relief on the diagnostic performance of ultrasonography (US) and on the appropriateness of the surgical decision.
A prospective randomized, double-blind placebo-controlled trial with morphine was conducted. A visual analog scale was used to evaluate pain in 340 patients aged 16 years or older. US was performed with a standardized protocol. Diagnosis was confirmed at histologic analysis or, in the patients released without surgery, at follow-up.
One hundred seventy-five patients were injected with morphine, and 165 were injected with the placebo. Pain relief was stronger in the morphine group. In the morphine group, US had lower (71.1%) sensitivity (difference, -9.5%; 95% CI, -18.5%, -0.5%) and higher (65.2%) specificity (difference, 11.4%; 95% CI, 1.0%, 21.8%). This group had also a higher positive predictive value (64.6%) and a lower negative predictive value (71.4%), but the differences between this group and the placebo group were not statistically significant. Among female patients, the decision to operate was appropriate more often in the morphine group (75.8%), but the difference between this group and the placebo group was not statistically significant (5.1%; 95% CI, -7.4%, 17.6%). In male patients and overall, opiate analgesia did not influence the appropriateness of the decision. The appropriateness to discharge patients without surgery was 100% in all groups.
Morphine does not improve US-based diagnosis of appendicitis.
Radiology 04/1999; 210(3):639-43. · 5.73 Impact Factor
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ABSTRACT: Transcranial Doppler sonography shows potential as a noninvasive technique for long-term follow-up of treated intracranial saccular aneurysms. This technical note describes a color Doppler artifact related to microcoil architecture that might represent a potential pitfall in transcranial Doppler sonographic evaluation of aneurysmal cavity thrombosis, since it may be wrongly interpreted as residual flow or aneurysmal cavity recanalization.
American Journal of Neuroradiology 03/1999; 20(2):246-7. · 2.93 Impact Factor
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ABSTRACT: Hepatocellular adenoma and focal nodular hyperplasia are two benign hepatic tumors which are mainly detected in healthy young women. Hepatocellular adenoma is an indication for surgery due to the risk of haemorrhage and malignant transformation. By contrast, focal nodular hyperplasia should be managed conservatively. However, precise diagnosis of these benign liver tumors remains difficult and sometimes impossible, despite new imaging techniques. Because of the risk of diagnostic error, resection or large biopsies of presumed liver tumors should be performed in young women (and a fortiori in men and older patients in whom focal nodular hyperplasia is less prevalent) when the diagnosis of focal nodular hyperplasia is not firmly established. The risk of liver surgery in young patients with normal liver parenchyma is, in the opinion of the authors, lower than the risk of a mistaken diagnosis.
Swiss Surgery 02/1999; 5(3):122-5.
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ABSTRACT: The purpose of this study was to assess the feasibility and accuracy of three-dimensional (3D) reconstruction techniques for digital subtraction angiography (DSA) in planning and evaluation of minimally invasive image-controlled therapy.
Using a standard, commercially available system, the authors acquired DSA images and corrected them for inherent distortions. They designed and implemented parallel and multiresolution versions of cone-beam reconstruction techniques to reconstruct high-resolution targeted volumes in a short period of time. Testing was performed on anatomically correct, calibrated in vitro models of a cerebral aneurysm. These models were used with a pulsatile circulation circuit to allow for blood flow simulation during DSA, computed tomographic (CT) angiography, and magnetic resonance (MR) angiography image acquisitions.
The multiresolution DSA-based reconstruction protocol and its implementation allowed the authors to achieve reconstruction times and levels of accuracy for the volume measurement of the aneurysmal cavities that were considered compatible with actual clinical practice. Comparison with data obtained from other imaging modalities shows that, besides vascular tree depiction, the DSA-based true 3D technique provides volume estimates at least as good as those obtained from CT and MR angiography.
The authors demonstrated the feasibility and potential of true 3D reconstruction for angiographic imaging with DSA. On the basis of the model testing, this work addresses both the timing and quantification required to support minimally invasive image-controlled therapy.
Academic Radiology 01/1999; 5(12):836-49. · 1.69 Impact Factor
