Artifact Reduction in the Diagnosis of Vasospasm in Computed Tomographic Perfusion: Potential of Iterative Metal Artifact Reduction.

Objective: This study aimed to analyze the possibility of artifact reduction using a new iterative metal artifact reduction algorithm (iMAR) in the diagnosis of perfusion deficits due to vasospasms and to evaluate its clinical relevance.

Methods: Sixty-one volume perfusion computed tomographies of 24 patients after coiling or aneurysm clipping were reconstructed using standard-filtered back-projection and iMAR retrospectively. The degree of artifacts was evaluated as well as the size of the nonevaluable area.

Hypercapnic BOLD MRI compared to HO PET/CT for the hemodynamic evaluation of patients with Moyamoya Disease.

Background And Purpose: Patients with Moyamoya Disease (MMD) need hemodynamic evaluation of vascular territories at risk of stroke. Today's investigative standards include HO PET/CT with pharmacological challenges with acetazolamide (ACZ). Recent developments suggest that CO-triggered blood‑oxygen-level-dependent (BOLD) functional MRI might provide comparable results to current standard methods for evaluation of territorial hemodynamics, while being a more widely available and easily implementable method.

Advanced diffusion-weighted imaging in patients with optic neuritis deficit - value of reduced field of view DWI and readout-segmented DWI.

Objective The objective of this article is to evaluate advanced techniques of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) measurements of the optic nerve in patients with optic neuritis. Methods In this prospective and institutional review board-approved trial, we examined 15 patients with acute visual loss and clinical signs of optic neuritis including thin-slice multi-shot segmented readout of long variable echo trains (rs-EPI, RESOLVE) DWI and reduced field-of view DWI using a parallel transmit system (rFOV-EPI). Conventional single-shot echo-planar DWI (ss-EPI) of the whole brain was available in 13 patients.

Impact of Papillary Muscle Infarction on Ischemic Mitral Regurgitation Assessed by Magnetic Resonance Imaging.

Objective: Ischemic mitral regurgitation is a predictor of heart failure resulting in increased mortality in patients with chronic myocardial infarction. It is uncertain whether the presence of papillary muscle (PM) infarction contributes to the development of mitral regurgitation in patients with chronic myocardial infarction (MI). The aim of the present study was to assess the correlation of PM infarction depicted by MRI with mitral regurgitation and left ventricular function.

Morphologic and Clinical Outcome of Intracranial Aneurysms after Treatment Using Flow Diverter Devices: Mid-Term Follow-Up.

Flow diverters (FDs) are designed for the endovascular treatment of complex intracranial aneurysm configurations. From February 2009 to March 2013 28 patients (22 females, 6 males) were treated with FD; mean age was 57 years. Data, including aneurysm features, clinical presentation, history of previous bleeding, treatment, and follow-up results, are presented.

Parallel-transmit-accelerated 2D Selective RF Excitation MR of the Temporal Bone: Enhanced Resolution of Labyrinthine and IAC Structures.

Rationale And Objectives: The purpose of this study was to compare a standard T2 SPACE sequence (standard-SPACE) used in temporal bone imaging at 3 T with a new parallel-transmit-accelerated 2D-selective radio frequency excitation technique for SPACE which was either time-improved or resolution-improved.

Materials And Methods: Thirty-two consecutive patients were examined in this IRB-approved study using a standard T2 SPACE sequence, and then a time-improved zoomed SPACE sequence (short z-SPACE) with identical resolution but accelerated image acquisition and a resolution-improved zoomed SPACE sequence (high-resolution z-SPACE) with identical acquisition time but higher resolution at a 3-T magnetic resonance imaging system. Signal-to-noise ratio (SNR) was measured within selected regions of interest.

Feasibility and evaluation of dual-source transmit 3D imaging of the orbits: Comparison to high-resolution conventional MRI at 3T.

Purpose: To prospectively compare the image quality and diagnostic performance of orbital MR images obtained by using a dual-source parallel transmission (pTX) 3D sequence (Sampling Perfection with Application optimized Contrasts using different flip angle Evolution, SPACE) with the image quality of conventional high-resolution standard protocol for clinical use in patients at 3T.

Materials And Methods: After obtaining institutional review board approval and patient consent, 32 patients with clinical indication for orbital MRI were examined using a high-resolution conventional sequences and 3D pTX SPACE sequences. Quantitative measurements, image quality of the healthy orbit, incidence of artifacts, and the subjective diagnostic performance to establish diagnosis was rated.

Acute stroke imaging: feasibility and value of MR angiography with high spatial and temporal resolution for vessel assessment and perfusion analysis in patients with wake-up stroke.

Rationale And Objectives: Magnetic resonance (MR) imaging (MRI) provides information that can be used to estimate the symptom onset in patients with wake-up stroke (WUS). Time-resolved MR angiography (MRA) is the fastest available MR sequence technique for vessel assessment, and the different phases acquired can provide information about cerebral perfusion. The aim of this study was to evaluate the diagnostic performance of time-resolved MRA both for the assessment of vessel morphology and for the feasibility of perfusion.

Comparison of three different MR perfusion techniques and MR spectroscopy for multiparametric assessment in distinguishing recurrent high-grade gliomas from stable disease.

Rationale And Objectives: Magnetic resonance (MR) perfusion techniques and MR spectroscopy (MRS) provide specific physiological information that may allow distinction between recurrent glioma and progression from stable disease.

Materials And Methods: Forty patients underwent conventional MR imaging, dynamic contrast-enhanced T1-weighted perfusion imaging, dynamic susceptibility contrast-enhanced perfusion imaging (DSC), and multivoxel MRS. Arterial spin labeling was available in 26 of these patients.

Diagnostic value of high spatial and temporal resolution time-resolved MR angiography in the workup of peripheral high-flow vascular malformations at 1.5 Tesla.

To evaluate the feasibility and diagnostic impact of time-resolved MR angiography (TR-MRA) combined with parallel imaging and low contrast dose for the assessment of peripheral high-flow vascular malformations (VM) at 1.5 Tesla (T). Twelve consecutive patients (7 female, 5 male, mean age 24.

Pretreatment evaluation of peripheral vascular malformations using low-dose contrast-enhanced time-resolved 3D MR angiography: initial results in 22 patients.

Objective: The objective of our study was to assess the feasibility and diagnostic performance of time-resolved MR angiography (MRA) in the pretreatment evaluation of peripheral vascular malformations at 1.5 T.

Subjects And Methods: Twenty-two consecutive patients (15 women and seven men; mean age, 22.

Fusion of MR coronary angiography and viability imaging: feasibility and clinical value for the assignment of myocardial infarctions.

Purpose: To investigate the feasibility of image fusion of MR-coronary angiography (MRCA) and delayed gadolinium enhancement imaging (LGE) and to assign areas of myocardial infarction to the corresponding supplying coronary arteries.

Materials And Methods: An interactive segmentation of the coronary arteries was performed in MRCA data sets (n=25). The LGE slices were matched onto the vessel segmentation to perform a fused analysis of coronary artery anatomy and LGE.

Impact of restrictive physiology on intrinsic diastolic right ventricular function and lusitropy in children and adolescents after repair of tetralogy of Fallot.

Background: Restrictive right ventricular (RV) physiology is a phenomenon considered potentially beneficial when detected in children and adolescents with repaired tetralogy of Fallot (ToF). It is typically characterised by antegrade flow in the pulmonary artery in late diastole at the time of atrial contraction. However, little is known about the impact of restrictive physiology on intrinsic diastolic RV function or lusitropy.

Low-dose, time-resolved, contrast-enhanced 3D MR angiography in the assessment of the abdominal aorta and its major branches at 3 Tesla.

Rationale And Objectives: The aims of this study were to evaluate the effectiveness of low-dose, contrast-enhanced (CE), time-resolved, three-dimensional magnetic resonance angiography (MRA) in the assessment of the abdominal aorta and its major branches at 3 T and to compare the results with those of high-spatial resolution CE MRA.

Materials And Methods: Twenty-two consecutive patients (eight men, 14 women; mean age, 43.9 +/- 17.

Determination of unknown high-grade atherosclerotic lesions by whole-body cardiovascular imaging: assessment of patients with symptomatic atherosclerotic disease of peripheral arteries.

Rationale And Objectives: The long-term prospects for patients with peripheral-arterial-occlusive disease (PAOD) must be considered in the context of coexistent generalized atherosclerosis. We sought to determine the added clinical information of noninvasive magnetic resonance imaging (MRI) for detecting asymptomatic atherosclerotic disease in patients already at high risk.

Materials And Methods: Eighty-four patients (64 men, mean age 66.

Three-dimensional cine MRI in free-breathing infants and children with congenital heart disease.

Background: Patients with congenital heart disease frequently have complex cardiac and vascular malformations requiring detailed non-invasive diagnostic evaluation including functional parameters.

Objective: To evaluate the morphological and functional information provided by a novel 3-D cine steady-state free-precession (SSFP) sequence.

Materials And Methods: Twenty consecutive children (mean age 2.

High resolution myocardial magnetic resonance stress perfusion imaging at 3 T using a 1 M contrast agent.

Objective: Stress perfusion magnetic resonance imaging (MSPMRI) is an established technique for the assessment of myocardial perfusion. Shortcomings at 1.5 T are low signal to noise ratio (SNR) and contrast to noise ratio (CNR).

Towards risk stratification in systemic atherosclerosis: value of myocardial function and viability imaging as an adjunct to MR angiography.

Objectives: To longitudinally assess the value of cardiac functional and viability imaging as a supplement to MR angiography in patients with atherosclerotic disease.

Methods: Cardiac MRI was performed in 195 consecutive patients with symptomatic peripheral arterial disease. Of these, 186 patients were followed for 22 +/- 5 months for the presence of cardiac events (cardiac death, acute coronary syndrome and hospitalisation as a result of congestive heart failure).

Risk stratification by adenosine stress cardiac magnetic resonance in patients with coronary artery stenoses of intermediate angiographic severity.

Objectives: The purpose of this study was to determine the role of adenosine stress cardiac magnetic resonance (CMR) for risk stratification in patients with coronary artery stenoses of intermediate angiographic severity.

Background: Coronary angiography only provides a morphological description of coronary lesions. As the patient's prognosis is closely related to the functional significance of angiographically detected coronary lesions, a functional assessment is desirable in patients with coronary artery stenoses of intermediate severity.

Comparison between a linear versus a macrocyclic contrast agent for whole body MR angiography in a clinical routine setting.

Background: Previous experiences of whole body MR angiography are predominantly available in linear 0.5 M gadolinium-containing contrast agents. The aim of this study was to compare image quality on a four-point scale (range 1-4) and diagnostic accuracy of a 1.

Intraindividual comparison of myocardial delayed enhancement MR imaging using gadobenate dimeglumine at 1.5 T and 3 T.

For contrast-enhanced imaging techniques relying on strong T1 weighting, 3 T provides increased contrast compared with 1.5 T. The aim of our study was the intraindividual comparison of delayed enhancement MR imaging at 1.

Ultrafast whole-body MR angiography with two-dimensional parallel imaging at 3.0 T: feasibility study.

The study was approved by the local ethics committee, and informed consent was provided by all participants prior to the examination. The aim of the study was to assess the feasibility of whole-body three-dimensional (3D) contrast material-enhanced magnetic resonance (MR) angiography with parallel imaging in the phase- and section-encoding directions (ie, integrated parallel acquisition technique [iPAT(2); Siemens, Erlangen, Germany]) for all anatomic imaging stations in combination with a single injection of contrast material. Whole-body contrast-enhanced MR angiography was performed in 23 patients at 3.