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1.
J Cardiovasc Magn Reson ; 18(1): 86, 2016 Nov 15.
Article in English | MEDLINE | ID: mdl-27846914

ABSTRACT

There were 116 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2015, which is a 14 % increase on the 102 articles published in 2014. The quality of the submissions continues to increase. The 2015 JCMR Impact Factor (which is published in June 2016) rose to 5.75 from 4.72 for 2014 (as published in June 2015), which is the highest impact factor ever recorded for JCMR. The 2015 impact factor means that the JCMR papers that were published in 2013 and 2014 were cited on average 5.75 times in 2015. The impact factor undergoes natural variation according to citation rates of papers in the 2 years following publication, and is significantly influenced by highly cited papers such as official reports. However, the progress of the journal's impact over the last 5 years has been impressive. Our acceptance rate is <25 % and has been falling because the number of articles being submitted has been increasing. In accordance with Open-Access publishing, the JCMR articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. For this reason, the Editors have felt that it is useful once per calendar year to summarize the papers for the readership into broad areas of interest or theme, so that areas of interest can be reviewed in a single article in relation to each other and other recent JCMR articles. The papers are presented in broad themes and set in context with related literature and previously published JCMR papers to guide continuity of thought in the journal. We hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality papers to JCMR for publication.


Subject(s)
Cardiovascular Diseases/diagnostic imaging , Magnetic Resonance Imaging , Periodicals as Topic , Animals , Bibliometrics , Cardiovascular Diseases/pathology , Cardiovascular Diseases/physiopathology , Cardiovascular Diseases/therapy , Editorial Policies , Humans , Journal Impact Factor , Predictive Value of Tests , Prognosis
2.
J Cardiovasc Magn Reson ; 18: 2, 2016 Jan 06.
Article in English | MEDLINE | ID: mdl-26738482

ABSTRACT

BACKGROUND: In vivo cardiac diffusion tensor imaging (cDTI) is uniquely capable of interrogating laminar myocardial dynamics non-invasively. A comprehensive dataset of quantative parameters and comparison with subject anthropometrics is required. METHODS: cDTI was performed at 3T with a diffusion weighted STEAM sequence. Data was acquired from the mid left ventricle in 43 subjects during the systolic and diastolic pauses. Global and regional values were determined for fractional anisotropy (FA), mean diffusivity (MD), helix angle gradient (HAg, degrees/%depth) and the secondary eigenvector angulation (E2A). Regression analysis was performed between global values and subject anthropometrics. RESULTS: All cDTI parameters displayed regional heterogeneity. The RR interval had a significant, but clinically small effect on systolic values for FA, HAg and E2A. Male sex and increasing left ventricular end diastolic volume were associated with increased systolic HAg. Diastolic HAg and systolic E2A were both directly related to left ventricular mass and body surface area. There was an inverse relationship between E2A mobility and both age and ejection fraction. CONCLUSIONS: Future interpretations of quantitative cDTI data should take into account anthropometric variations observed with patient age, body surface area and left ventricular measurements. Further work determining the impact of technical factors such as strain and SNR is required.


Subject(s)
Anthropometry , Diffusion Tensor Imaging , Heart/anatomy & histology , Heart/physiology , Ventricular Function, Left , Adult , Age Factors , Aged , Analysis of Variance , Anisotropy , Body Surface Area , Diastole , Female , Healthy Volunteers , Humans , Image Interpretation, Computer-Assisted , Linear Models , Male , Middle Aged , Predictive Value of Tests , Sex Factors , Stroke Volume , Systole , Young Adult
3.
J Cardiovasc Magn Reson ; 17: 99, 2015 Nov 20.
Article in English | MEDLINE | ID: mdl-26589839

ABSTRACT

There were 102 articles published in the Journal of Cardiovascular Magnetic Resonance (JCMR) in 2014, which is a 6% decrease on the 109 articles published in 2013. The quality of the submissions continues to increase. The 2013 JCMR Impact Factor (which is published in June 2014) fell to 4.72 from 5.11 for 2012 (as published in June 2013). The 2013 impact factor means that the JCMR papers that were published in 2011 and 2012 were cited on average 4.72 times in 2013. The impact factor undergoes natural variation according to citation rates of papers in the 2 years following publication, and is significantly influenced by highly cited papers such as official reports. However, the progress of the journal's impact over the last 5 years has been impressive. Our acceptance rate is <25% and has been falling because the number of articles being submitted has been increasing. In accordance with Open-Access publishing, the JCMR articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. For this reason, the Editors have felt that it is useful once per calendar year to summarize the papers for the readership into broad areas of interest or theme, so that areas of interest can be reviewed in a single article in relation to each other and other recent JCMR articles. The papers are presented in broad themes and set in context with related literature and previously published JCMR papers to guide continuity of thought in the journal. We hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality papers to JCMR for publication.


Subject(s)
Biomedical Research , Cardiology , Cardiovascular Diseases/diagnosis , Magnetic Resonance Imaging , Periodicals as Topic , Animals , Bibliometrics , Biomedical Research/statistics & numerical data , Cardiology/statistics & numerical data , Cardiovascular Diseases/pathology , Cardiovascular Diseases/physiopathology , Editorial Policies , Humans , Journal Impact Factor , Magnetic Resonance Imaging/statistics & numerical data , Periodicals as Topic/statistics & numerical data , Predictive Value of Tests , Prognosis , Severity of Illness Index , Time Factors
4.
Arch Pediatr ; 19(7): 707-10, 2012 Jul.
Article in French | MEDLINE | ID: mdl-22652518

ABSTRACT

Sarcoidosis, a chronic multisystem inflammatory granulomatous disorder of unknown origin, is a rare disease in children. Two distinct clinical presentations of sarcoidosis in childhood are known. Older children usually show multisystem disease, close to the adult manifestation, with lung infiltration and frequent hilar lymphadenopathy. Prior to the age of 5, sarcoidosis reveals more frequently with the classical triad of rash, arthritis, and uveitis. Due to non-specific clinical features and the lack of a specific test, recognizing sarcoidosis can be difficult in the pediatric population. Moreover, unlike in adults, lung involvement is rare in pediatric sarcoidosis. Given the lack of a definitive blood test, the World Association of Sarcoidosis and Other Granulomatous disorders (WASOG) only recommends dosing the serum angiotensin-converting enzyme (ACE). Its level is usually higher in children than in adults, but an increased ACE may help in the diagnosis. The gold standard is a biopsy specimen with typical epithelioid gigantocellular granuloma without caseating necrosis granuloma, after other disorders known to cause granulomatous disease have been reasonably excluded. We report here the case of a 4.5-year-old male with the history of polyarthritis and uveitis, considered first as juvenile rheumatoid arthritis, followed 5 years later by cutaneous involvement, which led to reconsidering the diagnosis. There were no pulmonary clinical findings. Histology provided the diagnosis of sarcoidosis. He then developed dependence on steroids. The lack of the classical triad delayed the diagnosis several years. This case shows the pediatric singularity of sarcoidosis, which needs to be known so that early and appropriate follow-up can be conducted.


Subject(s)
Sarcoidosis/diagnosis , Age of Onset , Child, Preschool , Humans , Male
5.
Phlebology ; 27(7): 352-9, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22156366

ABSTRACT

OBJECTIVE: Assessment and optimization of intermittent pneumatic compression (IPC) devices for prophylaxis of deep vein thrombosis has previously used duplex ultrasound. The aim was to investigate novel magnetic resonance (MR) venous velocity mapping (VM) for IPC research and development. METHODS: Twelve normal subjects were scanned in the supine position using realtime MR VM with sequential foot and calf IPC (120 mmHg) at 1.5 T. Measurements were taken in the popliteal vein at baseline using both cuffs and each cuff individually recording 60 seconds continuously. Temporal resolution was 310 ms per independent image, at 1 × 1 mm spatial resolution. RESULTS: Peak velocity (V(p)) measurements: baseline, V(p) = 2.1 cm/second (range = 1.1-3.5); using both compression cuffs, V(p) = 41.5 cm/second (18.0-58.1); calf cuff alone, V(p) = 40.6 cm/second (18.1-62.2); foot cuff alone, V(p) = 7.9 cm/second (4.2-15.3). Flow volume measurements per compression cycle (F): baseline, F = 2.3 cm³ (0.5-11.4); both compression cuffs, F = 7.1 cm³ (2.5-24.6); calf cuff only, F = 7.1 cm³ (2.4-24.5); foot cuff only, F = 2.6 cm³ (0.9-10.7). The foot cuff contribution was insignificant when combined with the calf cuff (P < 0.01). The MR venous VM results were similar to those reported elsewhere using ultrasound. CONCLUSION: This novel technique for MR venous VM can measure the realtime variations in venous blood flow during IPC.


Subject(s)
Intermittent Pneumatic Compression Devices , Magnetic Resonance Imaging/methods , Phlebography/methods , Veins/pathology , Adult , Aged , Aged, 80 and over , Compression Bandages , Female , Foot/blood supply , Foot/diagnostic imaging , Humans , Image Processing, Computer-Assisted , Leg/blood supply , Leg/diagnostic imaging , Male , Middle Aged , Popliteal Vein/diagnostic imaging , Pressure , Supine Position , Time Factors , Ultrasonography, Doppler, Duplex , Venous Thrombosis/pathology
6.
Magn Reson Med ; 64(4): 1015-26, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20593372

ABSTRACT

A fully automatic and highly efficient free-breathing navigator gated technique, continuously adaptive windowing strategy (CLAWS), is presented. Using a novel and dynamic acquisition strategy that ensures all potential navigator acceptance windows are possible, CLAWS acquires an image with the highest possible efficiency regardless of variations in the respiratory pattern. Unnecessary prolongation of scan durations due to respiratory drift or navigator acceptance window adjustments are avoided. As CLAWS requires no setting of the acceptance window, nor monitoring of the navigator traces during the scan, operator dependence is minimized and ease of use improved. CLAWS was compared against a standard accept/reject algorithm (ARA) and an end-expiratory following ARA (EE-ARA) in 20 healthy subjects and 10 patients (ARA only). The respiratory efficiency was compared against the retrospectively determined best possible respiratory efficiency for each acquisition. On average, the difference between CLAWS scan times and best possible scan times was 0.6% (± 1.3%). For the ARA and EE-ARA techniques, mean differences were 14.4% (± 20.9%) and 32.6 ± 10.9%, respectively. Had the CLAWS algorithm been used with the ARA and EE-ARA traces, mean differences would have been 0.2% (± 1.1%) and 0.5% (± 1.7%), respectively. Image quality was the same for all techniques: respiratory gating, motion artifacts, navigator, and coronary artery imaging.


Subject(s)
Algorithms , Coronary Vessels/pathology , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Angiography/methods , Pattern Recognition, Automated/methods , Respiratory Mechanics , Respiratory-Gated Imaging Techniques/methods , Adolescent , Adult , Aged , Artificial Intelligence , Female , Humans , Image Enhancement/methods , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young Adult
7.
J Cardiovasc Magn Reson ; 12: 15, 2010 Mar 19.
Article in English | MEDLINE | ID: mdl-20302618

ABSTRACT

There were 56 articles published in the Journal of Cardiovascular Magnetic Resonance in 2009. The editors were impressed with the high quality of the submissions, of which our acceptance rate was about 40%. In accordance with open-access publishing, the articles go on-line as they are accepted with no collating of the articles into sections or special thematic issues. We have therefore chosen to briefly summarise the papers in this article for quick reference for our readers in broad areas of interest, which we feel will be useful to practitioners of cardiovascular magnetic resonance (CMR). In some cases where it is considered useful, the articles are also put into the wider context with a short narrative and recent CMR references. It has been a privilege to serve as the Editor of the JCMR this past year. I hope that you find the open-access system increases wider reading and citation of your papers, and that you will continue to send your quality manuscripts to JCMR for publication.


Subject(s)
Cardiovascular Diseases/diagnosis , Magnetic Resonance Imaging , Cardiovascular Diseases/physiopathology , Cardiovascular Diseases/therapy , Humans , Periodicals as Topic , Predictive Value of Tests , Prognosis
8.
Br J Radiol ; 82 Spec No 1: S24-32, 2009 Jan.
Article in English | MEDLINE | ID: mdl-20348532

ABSTRACT

Human right coronary artery (RCA) haemodynamics is investigated using computational fluid dynamics (CFD) based on subject-specific information from magnetic resonance (MR) acquisitions. The dynamically varying vascular geometry is reconstructed from MR images, incorporated in CFD in conjunction with pulsatile flow conditions obtained from MR velocity mapping performed on the same subject. The effects of dynamic vessel motion on instantaneous and cycle-averaged haemodynamic parameters, such as wall shear stress (WSS), time-averaged WSS (TAWSS) and oscillatory shear index (OSI), are examined by comparing an RCA model with a time-varying geometry and those with a static geometry, corresponding to nine different time-points in the cardiac cycle. The results show that the TAWSS is similar for the dynamic and static wall models, both qualitatively and quantitatively (correlation coefficient 0.89-0.95). Conversely, the OSI shows much poorer correlations (correlation coefficient 0.38-0.60), with the best correspondence being observed with the static models constructed from images acquired in late diastole (at t = 0 and 800 ms, the cardiac cycle is 900 ms). These findings suggest that neglecting dynamic motion of the RCA is acceptable if TAWSS is the primary focus but may result in underestimation of haemodynamic parameters related to the oscillatory nature of the blood flow.


Subject(s)
Coronary Vessels/physiology , Adult , Blood Flow Velocity/physiology , Coronary Vessels/anatomy & histology , Hemodynamics , Hemorheology/physiology , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Angiography/methods , Male , Models, Cardiovascular , Motion , Pulsatile Flow/physiology , Stress, Mechanical
9.
Dermatology ; 217(3): 203-6, 2008.
Article in English | MEDLINE | ID: mdl-18594143

ABSTRACT

Efalizumab was authorized to be put on the market in France starting July 21, 2005. Its efficacy and tolerance profile in plaque psoriasis at a dose of 1 mg kg(-1) weekly in a subcutaneous injection have been studied in phase III trials. At the current moment, more than 3,500 patients have been included in clinical trials. Flu-like symptoms (fever, chills, headaches, nausea, vomiting, myalgia) are the most frequent adverse events. On the skin, a localized papular rash or the aggravation of the psoriasis in an edematous or even pustular form are the two most regularly observed complications. At the biological level, hyperlymphocytosis and a temporary increase in alkaline phosphatases without clinical consequences are the most frequent anomalies. We report 2 adverse events under efalizumab that to our knowledge have never been described: a case of an eczematous rash and a case of thrombocytosis.


Subject(s)
Antibodies, Monoclonal/adverse effects , Eczema/chemically induced , Thrombocytosis/chemically induced , Adult , Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized , Female , Humans , Injections, Subcutaneous , Male , Psoriasis/drug therapy
10.
Proc Inst Mech Eng H ; 222(4): 475-85, 2008 May.
Article in English | MEDLINE | ID: mdl-18595359

ABSTRACT

A detailed investigation of left ventricle (LV) flow patterns could improve our understanding of the function of the heart and provide further insight into the mechanisms of heart failure. This study presents patient-specific modelling with magnetic resonance imaging (MRI) to investigate LV blood flow patterns in normal subjects. In the study, the prescribed LV wall movements based on the MRI measurements drove the blood flow in and out of the LV in computational fluid dynamics simulation. For the six subjects studied, the simulated LV flow swirls towards the aortic valve and is ejected into the ascending aorta with a vertical flow pattern that follows the left-hand rule. In diastole, the inflow adopts a reasonably straight route (with no significant secondary flow) towards the apex in the rapid filling phase with slight variations in the jet direction between different cases. When the jet reaches about two thirds of the distance from the inflow plane to the apex, the blood flow starts to change direction and swirls towards the apex. In the more slowly filling phase, a centrally located jet is evident with vortices located on both sides of the jet on an anterior-posterior plane that passes through the mitral and aortic valves. In the inferior-superior plane, a main vortex appears for most of the cases in which an anticlockwise vortex appears for three cases and a clockwise vortex occurs for one case. The simulated flow patterns agree well qualitatively with MRI-measured flow fields.


Subject(s)
Blood Flow Velocity/physiology , Blood Pressure/physiology , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Models, Cardiovascular , Stroke Volume/physiology , Ventricular Function , Computer Simulation , Heart Ventricles/anatomy & histology , Humans
12.
Ann Dermatol Venereol ; 135(4): 304-6, 2008 Apr.
Article in French | MEDLINE | ID: mdl-18420079

ABSTRACT

BACKGROUND: Congenital cutaneous leukaemia is rare. PATIENTS AND METHODS: A two-month-old girl presented bluish cutaneous macules of the trunk, histological examination of which suggested acute myeloid leukaemia (LAM B 5). The blood picture was negative for circulating tumour cells and the outcome under chemotherapy was favourable at one year of follow-up. DISCUSSION: The prognosis of congenital leukaemia is serious. Aleukaemic congenital leukaemia is seen occasionally but is rare. The existence of multiple cutaneous tumours in newborn infants raises the possibility of TORCH infection and of other malignant tumours such as nephroblastoma or neuroblastoma.


Subject(s)
Leukemia, Myeloid/pathology , Leukemic Infiltration , Skin/pathology , Female , Humans , Infant
15.
Med Phys ; 33(7): 2621-31, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16898466

ABSTRACT

Combined in vitro experiments and numerical simulations were performed to study flow artifacts in phase contrast (PC) velocity mapping of steady flow through an anatomically realistic aortocoronary bypass graft model. The geometry was obtained through imaging and computational reconstruction of a left anterior descending (LAD) coronary artery of a porcine heart. Simulated images of through-plane velocity were obtained at selected slices of the geometry. These were then compared and contrasted with velocity images of corresponding sites that were obtained from in vitro experiments. The shift and distortion of the measured velocity profile was well predicted by the simulation, while trajectories obtained from particle tracking were shown to be useful in understanding the origins of the flow artifacts that were observed.


Subject(s)
Coronary Artery Bypass , Coronary Vessels/pathology , Heart/diagnostic imaging , Magnetic Resonance Imaging/methods , Algorithms , Animals , Blood Flow Velocity , Computer Simulation , Coronary Circulation , Image Interpretation, Computer-Assisted , Image Processing, Computer-Assisted , Models, Cardiovascular , Models, Theoretical , Radiography , Software , Swine
16.
Atherosclerosis ; 183(2): 361-6, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16285999

ABSTRACT

PURPOSE: To determine, in asymptomatic subjects, the inter-study reproducibility of a three-dimensional (3D) volume selective fast spin echo (FSE) cardiovascular magnetic resonance sequence for the assessment of carotid artery wall volume as a measure of atheroma burden. METHODS: Inter-study reproducibility was evaluated in 16 asymptomatic volunteers (10 male, 6 female). Both carotid arteries were scanned twice with a median inter-scan time of 5 days. The images were acquired in cross-section, and the total carotid arterial wall volume (TWV) was calculated by subtraction of the total carotid lumen volume from the total outer carotid vessel volume. RESULTS: The mean carotid T1-weighted TWV for the first and second scans was 828 and 821 mm(3), respectively (mean difference 7 mm(3), p=0.45). The standard deviation (S.D.) of the differences between the measurements was 38 mm(3) yielding an inter-study coefficient of variation of 4.6%. The time for each study was approximately 30 min. For the longitudinal evaluation of carotid atheroma burden with pharmacological intervention versus placebo, 32 subjects would enable a difference of 38 mm(3) to be detected with a significance level of 5% with 80% power. CONCLUSION: Volumetric analysis with carotid CMR in asymptomatic subjects using a 3D volume-selective FSE is time-efficient with good inter-study reproducibility, and is well suited for longitudinal studies of carotid atheroma with reasonable sample sizes.


Subject(s)
Carotid Artery, Common/anatomy & histology , Carotid Artery, Internal/anatomy & histology , Magnetic Resonance Imaging/methods , Adult , Aged , Atherosclerosis/diagnosis , Carotid Artery Diseases/diagnosis , Female , Follow-Up Studies , Humans , Male , Middle Aged , Reference Values , Reproducibility of Results , Retrospective Studies , Risk Factors
17.
J Cardiovasc Magn Reson ; 6(2): 517-25, 2004.
Article in English | MEDLINE | ID: mdl-15137336

ABSTRACT

BACKGROUND: Aortic atherosclerosis and coronary artery disease (CAD) are closely linked. Early detection of aortic atherosclerosis with the adoption of appropriate preventive measures may therefore help to reduce mortality and morbidity related to CAD. Arterial remodeling, by which the wall adapts to physiological or pathological insults by a change in vessel size, is being increasingly recognized as an important aspect of atherosclerosis. In this prospective longitudinal study we used cardiovascular magnetic resonance (CMR) to detect aortic plaque and to study aortic wall remodeling in asymptomatic subjects. METHODS: We recruited 175 healthy volunteers (49 years, 110 men) and documented their cardiovascular risk profile. Each subject underwent echocardiogram (ECG)-gated T1-weighted spin-echo imaging of the infrarenal abdominal aorta at baseline and after 2 years. FINDINGS: Of the 175 subjects who volunteered at baseline, CMR was successful in 174 (99%), with one (0.6%) failure due to claustrophobia. At 2 years, follow-up scanning was performed in 169 subjects (97%). Infrarenal aortic plaque was identified at baseline in nine (5.2%) subjects. This was reconfirmed in all nine (100%) cases at 2-year follow-up. No new cases of infrarenal plaque were identified at follow-up. The signal characteristics of the plaque on the subtracted images of the Dixon method indicate that all plaques were fibrous. In the nine subjects with infrarenal plaque, the total plaque burden increased as assessed by the total wall volume (561 to 677 mm3, p = 0.0063). The total vessel volume also increased (1737 to 1835 mm3, p = 0.031) but there was no change in the total luminal volume (1175 to 1157 mm3, p = 0.29). CONCLUSIONS: Cardiovascular magnetic resonance detects subclinical aortic atherosclerosis, can follow plaque burden over time, and confirms the presence of Glagov remodeling with preservation of the lumen despite progression of plaque. Cardiovascular magnetic resonance is well suited for the longitudinal follow-up of the general population with atherosclerosis, may help in the understanding of the natural history of atherosclerosis, and in particular may help determine factors to retard disease progression at an early stage.


Subject(s)
Aorta, Abdominal/pathology , Aortic Diseases/pathology , Arteriosclerosis/pathology , Magnetic Resonance Imaging/methods , Feasibility Studies , Female , Humans , Longitudinal Studies , Male , Middle Aged , Prospective Studies
18.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 1415-8, 2004.
Article in English | MEDLINE | ID: mdl-17271959

ABSTRACT

The link between atherosclerosis and wall shear stress (WSS) has lead to considerable interest in the in vivo estimation of WSS. Both magnetic resonance imaging (MRI) and three-dimensional ultrasound (3DUS) are capable of providing the anatomical and flow data required for subject-specific computational fluid dynamics (CFD) simulations. This study compares, for the first time, predicted 3D flow patterns based on black blood MRI and 3DUS. Velocity fields in the carotid arteries of nine subjects have been reconstructed, and the haemodynamic wall parameters WSS, oscillatory shear index (OSI), WSS gradients (WSSG) and angle gradients (WSSAG) were computed and compared. There was a good qualitative agreement between results derived from MRI and 3DUS, embodied by a strong linear correlation between the patched representations of the haemodynamic wall parameters. The root-mean-square error between haemodynamic wall parameters was comparable to the range of the expected variability of each imaging technique (WSS: 0.411 N/m; OSI: 0.048; temporal WSSG: 2.29 N/(s.m/sup 2/); spatial WSSG: 150 N/m/sup 3/; WSSAG: 87.6 rad/m). In conclusion, MRI and 3DUS are comparable techniques for combining with CFD in the carotid artery. The relatively high cost of MRI favour 3DUS to MRI for future haemodynamic studies of superficial arteries.

19.
Physiol Meas ; 25(6): 1495-509, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15712727

ABSTRACT

Atherosclerosis is a major cause of morbidity and mortality. Its apparent link with wall shear stress (WSS) has led to considerable interest in the in vivo estimation of WSS. Determining WSS by combining medical images with computational fluid dynamics (CFD) simulations can be performed both with magnetic resonance imaging (MRI) and three-dimensional ultrasound (3DUS). This study compares predicted 3D flow patterns based on black blood MRI and 3DUS. Velocity fields in the carotid arteries of nine subjects have been reconstructed, and the haemodynamic wall parameters WSS, oscillatory shear index (OSI), WSS gradients (WSSG) and angle gradients (WSSAG) were compared between the two imaging techniques. There was a good qualitative agreement between results derived from MRI and 3DUS (average correlation strength above 0.60). The root mean square error between haemodynamic wall parameters was comparable to the range of the expected variability of each imaging technique (WSS: 0.411 N m(-2); OSI: 0.048; temporal WSSG: 150 N s(-1) m(-2); spatial WSSG: 2.29 N m(-3); WSSAG: 87.6 rad m(-1)). In conclusion, MRI and 3DUS are capable of providing haemodynamic parameters when combined with CFD, and the predictions are in most cases qualitatively and quantitatively similar. The relatively high cost of MRI and continuing improvement in ultrasound favour US to MRI for future haemodynamic studies of superficial arteries.


Subject(s)
Algorithms , Blood Flow Velocity/physiology , Carotid Arteries/diagnostic imaging , Carotid Arteries/physiology , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Models, Cardiovascular , Adult , Carotid Arteries/anatomy & histology , Computer Simulation , Echocardiography, Three-Dimensional/methods , Female , Humans , Information Storage and Retrieval/methods , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
20.
Med Phys ; 30(12): 3251-61, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14713092

ABSTRACT

Image-based Computational Fluid Dynamics (CFD) has become a popular tool for the prediction of in vivo flow profiles and hemodynamic wall parameters. Currently, Magnetic Resonance Imaging (MRI) is most widely used for in vivo geometry acquisition. For superficial arteries such as the carotids and the femoral artery, three-dimensional (3-D) extravascular ultrasound (3-DUS) could be a cost-effective alternative to MRI. In this study, nine healthy subjects were scanned both with MRI and 3-DUS. The reconstructed carotid artery geometries for each subject were compared by evaluating cross-sectional areas, centerlines, and carotid nonplanarity. Lumen areas agreed very well between the two different acquisition techniques, whereas centerlines and nonplanarity parameters showed measurable disagreement, possibly due to the different neck and head positions adopted for 3-DUS versus MRI. With the current level of agreement achieved, 3-DUS has the potential to become an inexpensive and fast alternative to MRI for image-based CFD modeling of superficial arteries.


Subject(s)
Anatomy, Cross-Sectional/methods , Carotid Arteries/anatomy & histology , Carotid Arteries/diagnostic imaging , Echocardiography, Three-Dimensional/methods , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Adult , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Subtraction Technique
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