1
|
Shetty AN, Pautler R, Ghaghada K, Rendon D, Gao H, Starosolski Z, Bhavane R, Patel C, Annapragada A, Yallampalli C, Lee W. A liposomal Gd contrast agent does not cross the mouse placental barrier. Sci Rep 2016; 6:27863. [PMID: 27298076 PMCID: PMC4906290 DOI: 10.1038/srep27863] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 05/26/2016] [Indexed: 12/26/2022] Open
Abstract
The trans-placental permeability of liposomal Gadolinium (Gd) nanoparticle contrast agents was evaluated in a pregnant mouse model. Pregnant Balb/c mice at 16.5 (±1) days of gestation were imaged using a 3D Spoiled Gradient Echo method at 9.4 T using two contrast agents: a clinically approved Gd chelate, Multihance® (gadobenate dimeglumine), and a novel experimental liposomal Gd agent. A Dynamic Contrast Enhancement (DCE) protocol was used to capture the dynamics of contrast entry and distribution in the placenta, and clearance from circulation. A blinded clinical radiologist evaluated both sets of images. A reference region model was used to measure the placental flow and physiological parameters; volume transfer constant (Ktrans), efflux rate constant (Kep). The Gd content of excised placentae and fetuses was measured, using inductively coupled plasma mass spectrometry (ICP-MS). MRI images of pregnant mice and ICP-MS analyses of placental and fetal tissue demonstrated undetectably low transplacental permeation of the liposomal Gd agent, while the clinical agent (Multihance) avidly permeated the placental barrier. Image interpretation and diagnostic quality was equivalent between the two contrast agents. Additional testing to determine both maternal and fetal safety of liposomal Gd is suggested.
Collapse
Affiliation(s)
- Anil N Shetty
- Department of Obstetrics and Gynecology, Texas Childrens Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| | - Robia Pautler
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
| | - Ketan Ghaghada
- Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas
| | - David Rendon
- Department of Obstetrics and Gynecology, Texas Childrens Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| | - Haijun Gao
- Department of Obstetrics and Gynecology, Texas Childrens Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| | | | - Rohan Bhavane
- Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas
| | | | - Ananth Annapragada
- Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas
| | - Chandrasekhar Yallampalli
- Department of Obstetrics and Gynecology, Texas Childrens Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| | - Wesley Lee
- Department of Obstetrics and Gynecology, Texas Childrens Hospital, 6621 Fannin Street, Houston, TX 77030, USA
| |
Collapse
|
2
|
Bannas P, François CJ, Reeder SB. Magnetic Resonance Angiography of the Upper Extremity. Magn Reson Imaging Clin N Am 2016. [PMID: 26216777 DOI: 10.1016/j.mric.2015.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The magnetic resonance angiography (MRA) toolbox includes a wide array of versatile methods for diagnosis and therapy planning in patients with a variety of upper extremity vascular pathologies. MRA can provide excellent image quality with high spatial and high temporal resolution without the disadvantages of ionizing radiation, iodinated contrast, and operator dependency. Contrast-enhanced techniques are preferred for their robustness, image quality, and shorter scan times. This article provides an overview of the available MRA techniques and a description of the clinical entities that are well suited for evaluation with contrast-enhanced MRA.
Collapse
Affiliation(s)
- Peter Bannas
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA; Department of Radiology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, Hamburg 20246, Germany.
| | - Christopher J François
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA
| | - Scott B Reeder
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792-3252, USA; Department of Biomedical Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA; Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705-2275, USA; Department of Medicine, University of Wisconsin-Madison, 1685 Highland Avenue, Madison, WI 53705-2281, USA; Department of Emergency Medicine, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792, USA
| |
Collapse
|
3
|
Nagpal P, Maller V, Garg G, Hedgire S, Khandelwal A, Kalva S, Steigner ML, Saboo SS. Upper Extremity Runoff: Pearls and Pitfalls in Computed Tomography Angiography and Magnetic Resonance Angiography. Curr Probl Diagn Radiol 2016; 46:115-129. [PMID: 26949062 DOI: 10.1067/j.cpradiol.2016.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 01/25/2016] [Indexed: 12/13/2022]
Abstract
Upper extremity vasculature can be affected by various traumatic and nontraumatic pathologies; however, the evaluation of these arteries can be challenging for the radiologists as well as for the clinicians. After an accurate history and clinical examination, imaging plays a vital role in the diagnosis and treatment planning of these patients. Depending on the urgency and the indication, upper extremity arteries may be evaluated by ultrasonography with color Doppler, computed tomography (CT), magnetic resonance imaging (MRI), or digital subtraction angiography. This review article discusses relevant imaging anatomy of the upper extremity arteries, presents CT and MRI protocols, briefly describes the state-of-the-art CT and MRI of various pathologies affecting the upper extremity arteries, and summarizes the important pearls needed for busy practicing radiologist.
Collapse
Affiliation(s)
- Prashant Nagpal
- Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, IA; Department of Radiology, Brigham and Women׳s Hospital, Harvard Medical School, Boston, MA.
| | - Vinod Maller
- Division of Interventional Radiology, Department of Radiology, University of Tennessee Health Science Center, Memphis, TN
| | - Gunjan Garg
- Department of Nuclear Medicine, Montefiore Medical Center, Albert Einstein College of Medicine, Yeshiva University, New York, NY
| | - Sandeep Hedgire
- Division of Cardiovascular Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Ashish Khandelwal
- Department of Radiology, Brigham and Women׳s Hospital, Harvard Medical School, Boston, MA
| | - Sanjeeva Kalva
- Division of Interventional Radiology, Department of Radiology, UT Southwestern Medical Center, Dallas, TX
| | - Michael L Steigner
- Department of Radiology, Brigham and Women׳s Hospital, Harvard Medical School, Boston, MA
| | - Sachin S Saboo
- Division of Cardiothoracic Imaging, Department of Radiology, UT Southwestern Medical Center, Dallas, TX
| |
Collapse
|
4
|
Vessie EL, Liu DM, Forster B, Kos S, Baxter K, Gagnon J, Klass D. A Practical Guide to Magnetic Resonance Vascular Imaging: Techniques and Applications. Ann Vasc Surg 2014; 28:1052-61. [DOI: 10.1016/j.avsg.2014.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 01/31/2014] [Accepted: 02/03/2014] [Indexed: 10/25/2022]
|
5
|
Faggioni L, Zampa V, Ortori S, Picano E, De Lucia R, Soldati E, Bongiorni MG, Neri E, Bartolozzi C. Time-resolved contrast-enhanced magnetic resonance angiography (CEMRA) of the left atrium–pulmonary veins complex with half dose of intravenous gadolinium-based contrast agent. Technical feasibility and comparison with a conventional CEMRA, full contrast dose protocol. Eur J Radiol 2012; 81:250-6. [DOI: 10.1016/j.ejrad.2010.12.096] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 12/28/2010] [Indexed: 11/30/2022]
|
6
|
Fryxell GE, Chouyyok W, Rutledge RD. Design and synthesis of chelating diamide sorbents for the separation of lanthanides. INORG CHEM COMMUN 2011. [DOI: 10.1016/j.inoche.2011.03.045] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
7
|
Abujudeh HH, Rolls H, Kaewlai R, Agarwal S, Gebreananya ZA, Saini S, Schaefer PW, Kay J. Retrospective assessment of prevalence of nephrogenic systemic fibrosis (NSF) after implementation of a new guideline for the use of gadobenate dimeglumine as a sole contrast agent for magnetic resonance examination in renally impaired patients. J Magn Reson Imaging 2009; 30:1335-40. [DOI: 10.1002/jmri.21976] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
|
8
|
Sardanelli F, Di Leo G, Aliprandi A, Flor N, Papini GD, Roccatagliata L, Cotticelli B, Nano G, Cornalba G. Evaluation of carotid vessel wall enhancement with image subtraction after gadobenate dimeglumine-enhanced MR angiography. Eur J Radiol 2009; 70:589-94. [DOI: 10.1016/j.ejrad.2008.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 02/05/2008] [Accepted: 02/05/2008] [Indexed: 11/25/2022]
|
9
|
Weber MA, Giesel FL, Stieltjes B. MRI for identification of progression in brain tumors: from morphology to function. Expert Rev Neurother 2008; 8:1507-25. [PMID: 18928344 DOI: 10.1586/14737175.8.10.1507] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
For monitoring of brain tumors, it is crucial to identify progression or treatment failure early during follow-up to change treatment schemes and, thereby, optimize patient outcome. In the past years, several areas within the field of magnetic resonance (MR) have seen considerable advances: modern contrast media, advanced morphologic approaches and several functional techniques, for example, in the visualization of tumor perfusion or tumor cell metabolism. This review presents these recent advances by introducing the different techniques and outlining their benefit for identification of progression in brain tumors, with a focus on gliomas, metastases and meningiomas. After radiotherapy, MR spectroscopy helps to more accurately discriminate between radiation necrosis and glioma progression. In low-grade gliomas, perfusion MR techniques enable a more sensitive detection of anaplastic transformation than conventional MRI. Modern contrast media, as well as diffusion tensor imaging, allow for an improved tumor delineation and assessment of tumor extension. We will also highlight the biological background of these techniques, their applicability and current limitations. In conclusion, modern MRI techniques have been developed that are on the doorstep to be integrated in clinical routine.
Collapse
Affiliation(s)
- Marc-André Weber
- Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 10, D-69120 Heidelberg, Germany.
| | | | | |
Collapse
|
10
|
Three-dimensional contrast-enhanced magnetic-resonance angiography of the renal arteries: interindividual comparison of 0.2 mmol/kg gadobutrol at 1.5 T and 0.1 mmol/kg gadobenate dimeglumine at 3.0 T. Eur Radiol 2008; 18:1260-8. [PMID: 18278504 DOI: 10.1007/s00330-008-0873-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 11/19/2007] [Accepted: 01/09/2008] [Indexed: 10/22/2022]
Abstract
The purpose was to evaluate the image quality of high-spatial resolution MRA of the renal arteries at 1.5 T after contrast-agent injection of 0.2 mmol/kg body weight (BW) in an interindividual comparison to 3.0 T after contrast-agent injection of 0.1 mmol/kg BW contrast agent (CA). After IRB approval and informed consent, 40 consecutive patients (25 men, 15 women; mean age 53.9 years) underwent MRA of the renal arteries either at a 1.5-T MR system with 0.2 mmol/kg BW gadobutrol or at a 3.0-T MR scanner with 0.1 mmol/kg BW gadobenate dimeglumine used as CA in a randomized order. A constant volume of 15 ml of these contrast agents was applied. The spatial resolution of the MRA sequences was 1.0 x 0.8 x 1.0 mm(3) at 1.5 T and 0.9 x 0.8 x 0.9 mm(3) at 3.0 T, which was achieved by using parallel imaging acceleration factors of 2 at 1.5 T and 3 at 3.0 T, respectively. Two radiologists blinded to the administered CA and the field strength assessed the image quality and the venous overlay for the aorta, the proximal and distal renal arteries independently on a four-point Likert-type scale. Phantom measurements were performed for a standardized comparison of SNR at 1.5 T and 3.0 T. There was no significant difference (p > 0.05) between the image quality at 3.0 T with 0.1 mmol/kg BW gadobenate dimeglumine compared to the exams at 1.5 T with 0.2 mmol/kg BW gadobutrol. The median scores were between 3 and 4 (good to excellent vessel visualization) for the aorta (3 at 1.5 T/4 at 3.0 T for reader 1 and 2). For the proximal renal arteries, median scores were 3 for the left and right renal artery at 1.5 T for both readers. At 3.0 T, median scores were 3 (left proximal renal artery) and 4 (right proximal renal artery) for reader 1 and 3 (left/right) for reader 2 at 3.0 T. For the distal renal arteries, median scores were between 2 and 3 at both field strengths (moderate and good) for both readers. The kappa values for both field strengths were comparable and ranged between 0.571 (moderate) for the distal renal arteries and 0.905 (almost perfect) for the proximal renal arteries. In the phantom measurements, a 40% higher SNR was found for the measurements at 3 T with gadobenate dimeglumine. High-spatial resolution renal MRA at 3.0 T with 0.1 mmol/kg BW gadobenate dimeglumine yields at least equal image quality compared with renal MRA at 1.5 T with 0.2 mmol/kg BW gadobutrol.
Collapse
|
11
|
Kreitner KF, Schmitt R. MultiHance-enhanced MR angiography of the peripheral run-off vessels in patients with diabetes. ACTA ACUST UNITED AC 2008; 17 Suppl 6:F63-8. [DOI: 10.1007/s10406-007-0230-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
12
|
Abstract
In this chapter, the basic principles of magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) (Sects. 2.2, 2.3, and 2.4), the technical components of the MRI scanner (Sect. 2.5), and the basics of contrast agents and the application thereof (Sect. 2.6) are described. Furthermore, flow phenomena and MR angiography (Sect. 2.7) as well as diffusion and tensor imaging (Sect. 2.7) are elucidated.
Collapse
|
13
|
Meaney JF, Boyle G, O'Keeffe S. Contrast-enhanced magnetic resonance angiography: Current status, theoretical limitations and future potential. Radiography (Lond) 2007. [DOI: 10.1016/j.radi.2007.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
14
|
Michaely HJ, Kramer H, Dietrich O, Nael K, Lodemann KP, Reiser MF, Schoenberg SO. Intraindividual Comparison of High-Spatial-Resolution Abdominal MR Angiography at 1.5 T and 3.0 T: Initial Experience. Radiology 2007; 244:907-13. [PMID: 17709837 DOI: 10.1148/radiol.2443061647] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively compare three-dimensional (3D) contrast material-enhanced abdominal magnetic resonance (MR) angiography at 1.5 and 3.0 T intraindividually in healthy volunteers. MATERIALS AND METHODS After institutional review board approval and informed consent were obtained, 15 healthy male volunteers (age range, 24-41 years) underwent one abdominal 3D contrast-enhanced MR angiographic examination each at 1.5 and 3.0 T in random order. Fast 3D gradient-echo sequence with parallel imaging acceleration factor of three was used for MR angiography; acquired spatial resolutions were 1x0.8x1 mm3 (imaging time, 19 seconds) at 1.5 T and 0.9x0.8x0.9 mm3 (imaging time, 18 seconds) at 3.0 T. With the latter, volume of the 3D slab was 8% larger. At 1.5 T, 20-mL bolus of gadobenate dimeglumine was delivered at 2 mL/sec; at 3.0 T, 15-mL bolus was delivered at 2.5 mL/sec. Two blinded radiologists rated image quality of aorta and proximal renal arteries in consensus with five-point scale (4=very good, 0=nondiagnostic) according to sequence and in direct intraindividual comparison. Visibility of proximal and segmental renal arteries was rated with three-point scale (3=completely visible, 1=nonvisible). Signal-to-noise ratio (SNR) was determined with phantoms. For statistical analysis of the SNRs, t tests were used. RESULTS All MR angiographic measurements were diagnostic. Median score for image quality at both field strengths was 4. Depiction of proximal renal arteries was rated 3 at both field strengths. The visibility of the distal renal arteries was better at 3.0 T (median score, 3) than at 1.5 T (median score, 2). With direct comparison, 3.0-T MR angiography was better in 14 of 15 cases; no field strength was preferred in the other case. Mean SNR was significantly (P<.001) higher at 3.0 T (17.8+/-0.09 [standard deviation]) than at 1.5 T (11.9+/-0.10). CONCLUSION MR angiography at 3.0 T provided better vessel visibility and SNR than did that at 1.5 T, although voxel size and imaging time were reduced.
Collapse
Affiliation(s)
- Henrik J Michaely
- Institute of Clinical Radiology, University Hospitals Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistrasse 15, 81377 Munich, Germany.
| | | | | | | | | | | | | |
Collapse
|
15
|
Michaely HJ, Attenberger UI, Kramer H, Nael K, Reiser MF, Schoenberg SO. Abdominal and Pelvic MR Angiography. Magn Reson Imaging Clin N Am 2007; 15:301-14, v-vi. [PMID: 17893051 DOI: 10.1016/j.mric.2007.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Currently, 3T MR scanners hold 10% of the market with rising market share. Angiographic exams in particular benefit directly from the higher field strength. The theoretically doubled signal-to-noise ratio at 3T allows for abdominal magnetic-resonance angiography (MRA) exams with submillimeter spatial resolution with acquisition times of less than 20 seconds. Because of altered longitudinal relaxation times, MRA exams can be performed with a significantly reduced amount of contrast agents. This review describes the current technical concepts and outlines typical sequence parameters for abdominal and pelvic MRA. The choice of contrast agents for abdominal MRA is discussed in detail. This article also provides an outlook to new technical concepts that are already at the horizon of MRA.
Collapse
Affiliation(s)
- Henrik J Michaely
- Institute of Clinical Radiology, University Hospital Mannheim, Medical Faculty Mannheim-University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
| | | | | | | | | | | |
Collapse
|
16
|
Essig M, Weber MA, von Tengg-Kobligk H, Knopp MV, Yuh WTC, Giesel FL. Contrast-enhanced magnetic resonance imaging of central nervous system tumors: agents, mechanisms, and applications. Top Magn Reson Imaging 2007; 17:89-106. [PMID: 17198225 DOI: 10.1097/01.rmr.0000245464.36148.dc] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Brain tumors are one of the most common neoplasms in young adults and are associated with a high mortality and disability rate. Magnetic resonance imaging (MRI) is widely accepted to be the most sensitive imaging modality in the assessment of cerebral neoplasms. Because the detection, characterization, and exact delineation of brain tumors require a high lesion contrast that depends on the signal of the lesion in relation to the surrounding tissue, contrast media is given routinely. Anatomical and functional, contrast agent-based MRI techniques allow for a better differential diagnosis, grading, and especially therapy decision, planing, and follow-up. In this article, the basics of contrast enhancement of brain tumors will be reviewed. The underlying pathology of a disrupted blood-brain barrier and drug influences will be discussed. An overview of the currently available contrast media and the influences of dosage, field strength, and application on the tumor tissue contrast will be given. Challenging, contrast-enhanced, functional imaging techniques, such as perfusion MRI and dynamic contrast-enhanced MRI, are presented both from the technical side and the clinical experience in the assessment of brain tumors. The advantages over conventional, anatomical MRI techniques will be discussed as well as possible pitfalls and drawbacks.
Collapse
Affiliation(s)
- Marco Essig
- Department of Radiology, German Cancer Research Center, Heidelberg, Germany.
| | | | | | | | | | | |
Collapse
|
17
|
Kreitner KF, Kunz RP, Herber S, Martenstein S, Dorweiler B, Dueber C. MR angiography of the pedal arteries with gadobenate dimeglumine, a contrast agent with increased relaxivity, and comparison with selective intraarterial DSA. J Magn Reson Imaging 2007; 27:78-85. [DOI: 10.1002/jmri.21226] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
|
18
|
Michaely HJ, Dietrich O, Nael K, Weckbach S, Reiser MF, Schoenberg SO. MRA of abdominal vessels: technical advances. Eur Radiol 2006; 16:1637-50. [PMID: 16721552 DOI: 10.1007/s00330-006-0240-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 02/20/2006] [Accepted: 03/06/2006] [Indexed: 11/26/2022]
Abstract
Magnetic resonance angiography (MRA) in general and MRA of the abdominal vessels in particular have undergone substantial improvements in the past 5 years triggered by the introduction and application of parallel imaging (PI), new sequence techniques such as centric k-space trajectories and undersampling, dedicated contrast agents and clinical high-field scanners. All of these techniques have the potential to improve image quality and resolution or decrease the image acquisition time. However, each of them has its own specific advantages and drawbacks. This review describes the main technical innovations and focuses on the impact these developments may have on abdominal MRA. Special consideration is given to the interaction of these various technical advances. The clinical value of advanced MRA techniques is discussed and illustrated by characteristic cases.
Collapse
Affiliation(s)
- Henrik J Michaely
- Department of Clinical Radiology, University Hospitals - Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistr.15, 81377 Munich, Germany.
| | | | | | | | | | | |
Collapse
|
19
|
Schmitt R, Coblenz G, Cherevatyy O, Brunner H, Fröhner S, Wedell E, Karg G, Christopoulos G. Comprehensive MR angiography of the lower limbs: a hybrid dual-bolus approach including the pedal arteries. Eur Radiol 2005; 15:2513-24. [PMID: 16041527 DOI: 10.1007/s00330-005-2852-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Revised: 06/08/2005] [Accepted: 06/24/2005] [Indexed: 10/25/2022]
Abstract
The purpose of this study was to include the pedal vasculature into the coverage of peripheral multistation magnetic resonance angiography (3DceMRA). A total of 216 patients suffering from peripheral vascular disease were examined with a modified hybrid dual-bolus technique. The cruropedal arteries were acquired first with two sagittal slabs and time-resolved 3D sequences. Then the aortofemoral vessels were visualized using the bolus-chase technique and a second contrast injection. Interventional procedures were performed in 104 patients, and in 69 of those, the cruropedal vessels were also examined with digital subtraction angiography (iaDSA). Using 3DceMRA, the cruropedal arteries were displayed with both excellent and good quality in 95% (205/216 cases), and without any venous overlay in 94% (203/216 cases). The aortofemoral vessels were not jeopardized by the first contrast injection. With iaDSA as the standard of reference, observed sensitivity of 3DceMRA was found in ranges from 80% (29%, 99%) to 100% (86%, 100%) for assessing significant stenoses, and observed specificity ranged between 93% [80%, 98%] and 100% (82%, 100%). In conclusion, hybrid dual-bolus 3DceMRA significantly reduces the limitations of standard single-bolus 3DceMRA in anatomic coverage and temporal resolution of the cruropedal arteries, thus providing high-quality images of the entire peripheral vasculature.
Collapse
Affiliation(s)
- R Schmitt
- Diagnostic and Interventional Radiology, Herz- und Gefässklinik GmbH, Salzburger Leite 1, 97616, Bad Neustadt an der Saale, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Campa C, Rossi M, Flamigni A, Baiutti E, Coslovi A, Calabi L. Analysis of gadobenate dimeglumine by capillary zone electrophoresis coupled with electrospray-mass spectrometry. Electrophoresis 2005; 26:1533-40. [PMID: 15765487 DOI: 10.1002/elps.200410111] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Highly reliable and accurate analytical methods are needed for the determination of magnetic resonance imaging (MRI) contrast agents in complex matrices of clinical interest. We demonstrate the reliability of capillary zone electrophoresis (CZE) coupled with electrospray ionization-mass spectrometry (ESI-MS) for the analysis of MultiHance (gadobenate dimeglumine), a gadolinium-based MRI agent. A sheath liquid interface connected the CE system with an electrospray mass spectrometer equipped with an ion-trap analyzer. CZE with ultraviolet (CZE-UV) and with mass detection (CZE-MS) were compared by analyzing gadobenate dimeglumine and the free ligand diluted in water and in biological fluids (i.e., human serum and urine). The optimization of some relevant CZE-MS parameters was accomplished, like CE buffer composition, sheath liquid composition and flow, and type and length of the separation capillary. CZE-UV was highly influenced by the biological sample components, which hindered a reliable quantification of both gadobenate and free ligand in serum and urine. In CZE-MS, on the other hand, the electrophoretic runs turned out to be independent of the clinical matrices, due to the informative potential and to the selectivity of MS detection.
Collapse
|