Background and objectiveDysferlinopathies are a group of muscle disorders caused by mutations in the DYSF gene. Previous muscle imaging studies describe a selective pattern of muscle involvement in smaller patient cohorts, but a large imaging study across the entire spectrum of the dysferlinopathies had not been performed and previous imaging findings were not correlated with functional tests.MethodsWe present cross-sectional T1-weighted muscle MRI data from 182 patients with genetically confirmed dysferlinopathies. We have analysed the pattern of muscles involved in the disease using hierarchical analysis and presented it as heatmaps. Results of the MRI scans have been correlated with relevant functional tests for each region of the body analysed.ResultsIn 181 of the 182 patients scanned, we observed muscle pathology on T1-weighted images, with the gastrocnemius medialis and the soleus being the most commonly affected muscles. A similar pattern of involvement was identified in most patients regardless of their clinical presentation. Increased muscle pathology on MRI correlated positively with disease duration and functional impairment.ConclusionsThe information generated by this study is of high diagnostic value and important for clinical trial development. We have been able to describe a pattern that can be considered as characteristic of dysferlinopathy. We have defined the natural history of the disease from a radiological point of view. These results enabled the identification of the most relevant regions of interest for quantitative MRI in longitudinal studies, such as clinical trials.Clinical trial registrationNCT01676077.

Purpose: To evaluate whether dynamic imaging of the coronary arteries can be performed with intracoronary infusion of low-dose gadolinium (Gd)-based contrast agent and assess the effect of long duration and multiple infusions on the image signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Materials and Methods:Dynamic coronary magnetic resonance (MR) imaging (130 msec/image) and contrast agent first pass myocardial perfusion studies were performed with intracoronary infusions of low-dose Gd-based MR contrast agent on dogs (N ϭ 4) using a fast multislice gradient recalled echo (GRE) sequence.Results: Contrast-enhanced coronary arteries were clearly imaged during infusion periods as long as 2.3 minutes. The SNR and CNR of the contrast-enhanced coronary arteries remained essentially unchanged over multiple consecutive angiographic sessions. In addition, we demonstrated that first pass studies performed with intracoronary injection of MR contrast agent can be used as a means of assessing regional myocardial perfusion. Conclusion:These studies demonstrated that, using intracoronary infusion of Gd, coronary magnetic resonance angiography (MRA) can be performed with high temporal resolution, and multiple low-dose slow infusions of Gd-based MR contrast agent can be performed without compromise of the vessel SNR and CNR. VASCULAR INTERVENTIONS require high spatial resolution and fast angiographic imaging. Currently, contrast-enhanced x-ray angiography, with its real-time temporal resolution and sub-millimeter spatial resolution, is the method of choice for monitoring and performing vascular procedures. Several recent studies (1-5) suggest the potential of magnetic resonance (MR) imaging to guide vascular interventions. Compared to x-ray angiography, MR offers several benefits. First, because of its high contrast resolution and intrinsic sensitivity to flow, MR allows the assessment of both morphology and function. Second, unlike x-ray angiography, MR imaging is intrinsically three-dimensional, allowing free selection of volume and scan-planes. These can be selected to better visualize the procedure without manually repositioning the patient or imaging instrument. Third, MR imaging does not use ionizing radiation, and therefore is safer for both the medical staff and patient. In addition, MR gadolinium (Gd)-based contrast agents are less toxic and have fewer side effects than iodinated x-ray contrast agents (6,7).In principle, MR imaging can provide an integrated and comprehensive approach to vascular intervention, permitting diagnosis of a vascular pathological condition, guidance of a suitable intervention, and assessment of the interventional results during the same session and with the same modality. Recent studies have demonstrated MR visualization of vascular catheters and interventional devices with passive (8 -11) and active methods (2,(12)(13)(14), and contrast-enhanced angiography with submillimeter spatial resolution (15). In addition, MR guidance has been used in performing percutaneous translumina...

Purpose: To demonstrate the feasibility of detecting patency, stenosis, or occlusion of transjugular intrahepatic portosystemic shunts (TIPS) with 4D Flow MR. Materials and Methods: Sequential adult patients with TIPS were eligible for enrollment. A volumetric phase contrast sequence was used to image the TIPS. Particle tracing CINE images were used for qualitative assessment of stenosis. TIPS were segmented to generate quantitative data sets of peak velocity. Segmentation and quantitative measurement of flow throughout an entire TIPS stent defined technical success. Comparison was made to Doppler US. Venogram, when available, and 6-month clinical follow-up were used as reference standards. Results: 4D Flow MR was performed in 23 patient encounters, and was technically successful in 16/23 encounters. Three cases demonstrated both focal turbulence and abnormal velocities (>190cm/s or <90cm/s) on 4D Flow and had venogram confirmed stenosis (true positives). Seven cases had normal velocities and no turbulence on 4D Flow and all were confirmed negative with clinical follow-up or venogram (true negatives). Six cases had discordant 4D flow results, with abnormal velocities but no turbulence, or focal turbulence but normal velocities. All six discordant cases had no evidence of dysfunction with 6-month follow-up. Conclusion: 4D Flow MR can detect TIPS patency and stenosis, but requires further investigation before it can be used to assess for TIPS dysfunction.

HyPer 3D CE-MRA is an alternative method for time-resolved high-resolution peripheral CE-MRA in evaluating the trifurcation and feet vessels with no venous contamination.