Intra‐arterial magnetic resonance angiography of the iliac arteries: clinical experience using two different protocols

2005 ◽  
Vol 46 (3) ◽  
pp. 250-255 ◽  
Author(s):  
C. Paetzel ◽  
N. Zorger ◽  
M. Völk ◽  
T. Herold ◽  
J. Seitz ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Diagnostic Value ◽  
Conventional Angiography ◽  
Iliac Arteries ◽  
Contrast Enhanced ◽  
Group 2 ◽  
Magnetic Resonance Imaging Mri ◽  
Space Acquisition ◽  
Group 1

Purpose: To assess the feasibility of intra‐arterial magnetic resonance angiography (iaMRA) with two different protocols. Material and Methods: Twenty patients were prospectively examined after digital subtraction angiography. Contrast‐enhanced iaMRA was performed using a 1.5T magnetic resonance imaging (MRI) system. Contrast agent (gadodiamide) was injected through a conventional angiography catheter placed in the abdominal aorta. The patients were randomized into two groups each comprising 10 patients. Group 1 was examined with a FLASH‐3D (fast low‐angle shot) sequence, allowing the center of the k‐space to be acquired 0.5 s after initiation of the measurement. Group 2 was examined with the identical sequence, but the center of the k‐space was acquired after 8.7 s. The increase in the intravascular signal intensity was determined and the diagnostic value of the angiograms was independently scored by 4 investigators using a 5‐point scale. Results: Nineteen of 20 MRAs were scored as diagnostic; only 1 was scored as non‐diagnostic by 2 observers. The diagnostic value of the angiograms of group 2 was judged superior to that of group 1 owing to a more homogeneous intravascular contrast distribution. Conclusion: Intra‐arterial MRA is feasible. The diagnostic value of angiograms using a flash sequence with center of the k‐space acquisition after 8.7 s ranged from good to excellent. This sequence is appropriate for iaMRA of iliac arteries to support MR guided intervention.

Regional Cerebral Plasma Volume Response to Carbon Dioxide Using Magnetic Resonance Imaging 

1998 ◽  
Vol 88 (4) ◽  
pp. 984-992 ◽  
Author(s):  
Jean-Francois Payen ◽  
Albert Vath ◽  
Blanche Koenigsberg ◽  
Virginie Bourlier ◽  
Michel Decorps
Keyword(s):  
Magnetic Resonance Imaging ◽  
Carbon Dioxide ◽  
Magnetic Resonance ◽  
Plasma Volume ◽  
Resonance Imaging ◽  
Contrast Enhanced ◽  
Group 3 ◽  
Group 2 ◽  
Agent Group ◽  
Group 1

Background Noninvasive techniques used to determine the changes in cerebral blood volume in response to carbon dioxide are hampered by their limited spatial or temporal resolution or both. Using steady state contrast-enhanced magnetic resonance imaging, the authors determined regional changes in cerebral plasma volume (CPV) induced by hypercapnia in halothane-anesthetized rats. Methods Cerebral plasma volume was determined during normocapnia, hypercapnia and recovery in the dorsoparietal neocortex and striatum of each hemisphere, in cerebellum, and in extracerebral tissue of rats with either intact carotid arteries (group 1) or unilateral common carotid ligation (group 2). Another group was studied without injection of a contrast agent (group 3). Results Hypercapnia (partial pressure of carbon dioxide in arterial blood [PaCO2] approximately 65 mmHg) resulted in a significant increase in CPV in the striatum (+42 +/- 8%), neocortex (+34 +/- 6%), and cerebellum (+49 +/- 12%) compared with normocapnic CPV values (group 1). Carotid ligation (group 2) led to a marked reduction of the CPV response to hypercapnia in the ipsilateral striatum (+23 +/- 14%) and neocortex (+27 +/- 17%) compared with the unclamped side (+34 +/- 15% and +38 +/- 16%, respectively). No significant changes in CPV were found in extracerebral tissue. In both groups, the CPV changes were reversed by the carbon dioxide washout period. Negligible changes in contrast imaging were detected during hypercapnia without administration of the contrast agent (group 3). Conclusions The contrast-enhanced magnetic resonance imaging technique is sensitive to detect noninvasively regional CPV changes induced by hypercapnia in rat brain. This could be of clinical interest for determining the cerebrovascular reactivity among different brain regions.

Diagnostic value of magnetic resonance imaging in perimesencephalic and nonperimesencephalic subarachnoid hemorrhage of unknown origin

2011 ◽  
Vol 114 (4) ◽  
pp. 1003-1007 ◽  
Author(s):  
Homajoun Maslehaty ◽  
Athanassios K. Petridis ◽  
Harald Barth ◽  
Hubertus Maximilian Mehdorn
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Unknown Origin ◽  
Diagnostic Value ◽  
Digital Subtraction ◽  
Resonance Imaging ◽  
Bleeding Pattern ◽  
Group 2 ◽  
Group 1

Object The aim of this study was to evaluate the diagnostic value of MR imaging in perimesencephalic (PM) and nonperimesencephalic (non-PM) subarachnoid hemorrhage (SAH) of unknown origin. Methods The authors conducted a retrospective review of all patients with SAH (1226 patients) in their department between January 1991 and December 2008. Included in the study were cases of spontaneous SAH diagnosed using CT scans obtained within 24 hours of the initial symptoms and initially negative digital subtraction (DS) angiograms. Patients with traumatic SAH and an unknown history were excluded from the study. Patients with initially negative DS angiograms were divided into 2 groups: Group 1, a typically PM bleeding pattern (PM SAH); and Group 2, a non-PM bleeding pattern (non-PM SAH) such as hemorrhage in the sylvian or interhemispheric fissure. Cranial MR imaging including the craniocervical region was performed within 72 hours after SAH was diagnosed in all patients in Groups 1 and 2. Results One thousand sixty-eight patients underwent DS angiography, and among them were 179 (16.7%) with negative angiograms—47 patients (26.3%) from Group 1 and 132 patients (73.7%) from Group 2. Magnetic resonance imaging demonstrated no bleeding sources in any case (100% negative). Thirty-four patients in Group 1 and 120 patients in Group 2 underwent a second DS angiography study. Digital subtraction angiography revealed an aneurysm as the bleeding source in 1 case in Group 1 and in 13 cases in Group 2. Conclusions Magnetic resonance imaging of the brain and craniocervical region did not produce additional benefit for the detection of a bleeding source and the therapy administered for PM SAH and non-PM SAH (100% negative). The costs of this examination exceeded the clinical value. Despite the results of this study, MR imaging should be discussed on a case-by-case basis because rare bleeding sources are periodically diagnosed in cases of non-PM SAH. A second-look DS angiogram is necessary because aneurysmal hemorrhage occasionally produces PM SAH as well as non-PM SAH. Further prospective studies are needed to verify the authors' results in the future.

Ordered k-space acquisition in contrast enhanced magnetic resonance angiography (CE-MRA)

2008 ◽  
Author(s):  
B. Wu ◽  
J. R. Maclaren ◽  
R. P. Millane ◽  
R. Watts ◽  
P. J. Bones
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Contrast Enhanced ◽  
Space Acquisition

scholarly journals Contrast enhanced magnetic resonance imaging in assessment of aortic atherosclerosis and its relation to severity of myocardial injury due to infarction

2019 ◽  
pp. 10-14
Author(s):  
A. S. Maksimova ◽  
V. E. Sinitsyn ◽  
Yu. B. Lishmanov ◽  
W. Yu. Ussov
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Myocardial Injury ◽  
Aortic Wall ◽  
Aortic Atherosclerosis ◽  
Resonance Imaging ◽  
Contrast Enhanced ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Aim. To study the contrast enhanced magnetic resonance imaging (CE-MRI) role in assessment of aortic atherosclerosis and its relation to severity of myocardial injury in myocardial infarction (MI) patients which underwent cardiac MRI before coronary artery bypass grafting and Dor or Menicanti procedures.Material and methods. The study included 42 patients (38 men, 4 women) who underwent CE-MRI (mean age 57,7±8,75 years). In order to analyze the aortic atherosclerosis, axial T1 weighted images before and after 10-15 minutes after CE was evaluated. Along with visual analysis, the diameter, thickness of the aortic wall, and index of enhancement (IE) of T1 weighted image (WI) (TR=400-650 ms, TE=12-20 ms), as the ratio of postand precontrast intensities of the aortic wall: IE=(Intensity T1-WI post-contrast)/ (Intensity T1-WI pre-contrast) were determined. According to the cardiac CEMRI, the proportion of left ventricle (LV) injury as the ratio of the MI injury and theLV mass was estimated.Results. Depending on aortic IE value, patients were divided into three groups: group 1 (9 people) with IE ≤1,05; group 2 (15 people) with 1,05< IE ≤1,15; group 3 (18 people) with IE >1,15. We compared the descending aortic wall thickness and the diameter among these groups. To identify intergroup differences one-way ANOVA with Bonferroni correction was carried out. There were no significant differences in the descending aortic diameters (F=0,15; p=0,86): group 1 — 2,41±0,33, group 2 — 2,54±0,63, group 3 — 2,53±0,51 cm. The thickness of the aortic wall in groups was 2,05±0,58 mm, 3,34±0,68 mm and 3,80±0,46 mm (F=17,39; p< 0,001), respectively. The first and second, first and third groups were distinguished, and there was no significant difference between the second and third groups. Between groups 1, 2 and 3 were also noted the increase and differences in proportion of LV injury, which amounted to 0,11±0,03 with a minimum IE (group 1), with an intermediate IE (group 2) — 0,19±0,08, and with high IE — 0,25±0,15.Conclusion. CE-MRI of the aortic wall can be used as a method of visualizing atherosclerosis and predicting the complications of aortic atherosclerosis. Moreover, the assessment of aortic atherosclerosis can be used in combination with conventional heart examination. The increased CE into the aortic wall in patients with advanced atherosclerosis is usually associated with a greater severity of myocardial injury. During cardiac CE-MRI it is advisable to assess the descending aorta state by calculation of IE T1-WI MRI to clarify the atherosclerosis severity and cardiovascular risk.

Contrast-enhanced magnetic resonance angiography of the iliac arteries: Optimization by injection simulation

2001 ◽  
Vol 46 (2) ◽  
pp. 365-373 ◽  
Author(s):  
M.A. Schmidt ◽  
A.J. Britten ◽  
M.A. Tomlinson ◽  
S. Vig ◽  
S. Powell ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Iliac Arteries ◽  
Contrast Enhanced ◽  
Injection Simulation

scholarly journals Evaluation of Patients with Vertigo by Cranial Magnetic Resonance Imaging (MRI)

2021 ◽  
Vol 21 (1) ◽  
pp. 1-12
Author(s):  
Treefa Salih Hasan ◽  
Keyword(s):  
Magnetic Resonance ◽  
Diagnostic Yield ◽  
Vascular Lesion ◽  
Mri Findings ◽  
Important Diagnostic Tool ◽  
Vascular Origin ◽  
Male Patients ◽  
Group 2 ◽  
Magnetic Resonance Imaging Mri ◽  
Group 1

Background: Vertigo is a symptom that neurologists and otologists are confronted with. Magnetic resonance image (MRI) is used for imaging. Objective: To determine the diagnostic yield of MRI in patients with vertigo and to Identify the most common causes. Patients and Methods: This observational study involved 110 vertigo complaining patients attending the MRI unit of Rizgary teaching hospital examined by 0.2 Tesla MRI between June 2007 and September 2008.Collected variables divided into Group 1 (normal MRI) and Group 2 (abnormal MRI) analysed and compared. Results: Group 1= (70%) and Group 2=(30%), abnormal MRI findings in male patients was (59.6%), in female (40.4%,) the commonest abnormalities were cerebellopontine angle (CPA) space occupying lesions (SOL) (9.2%), cerebellar SOL (7.4%), 4th ventricle SOL (7.4%) and deep white matter ischemia (7.4%), most of patients with vascular problems were more than 50 years. In (35.4%) of patients, vertigo was less than one month duration, (50%) of which had abnormal MRI findings. Out of seven patients with normal MRI, 5 patients showed vascular lesion on magnetic resonance angiography (MRA). Conclusion: MRI remains important diagnostic tool for evaluation of vertigo and MRA is necessary when vascular origin is suspected.

Sign in / Sign up

Export Citation Format

Share Document