Contrast Media in Pregnant and Lactating Patients, From the Special Series on Contrast Media.

IV contrast media improve the diagnostic power of radiology examinations. These media include gadolinium-based contrast media and iron-oxide nanoparticles for MRI, iodinated contrast material for CT, microbubbles for ultrasound, and radiopharmaceuticals for nuclear medicine. As for all medications, contrast media carry risks, which may be heightened in the conditions of pregnancy and lactation.

Multimodality Imaging of a Mass Arising from a Cor Triatriatum Sinister Membrane.

Cor triatriatum sinister is a rare entity characterized by a membrane within the left atrium and posterior to the atrial appendage. This defect may cause obstructive symptoms analogous to mitral stenosis. The authors present a case of an incidentally detected enhancing mass originating from a cor triatriatum sinister membrane, with imaging characteristics most suggestive of myxoma.

Non-Contrast Magnetic Resonance Angiography: Techniques, Principles, and Applications.

Several non-contrast magnetic resonance angiography (MRA) techniques have been developed, providing an attractive alternative to contrast-enhanced MRA and a radiation-free alternative to computed tomography (CT) CT angiography. This review describes the physical principles, limitations, and clinical applications of bright-blood (BB) non-contrast MRA techniques. The principles of BB MRA techniques can be broadly divided into (a) flow-independent MRA, (b) blood-inflow-based MRA, (c) cardiac phase dependent, flow-based MRA, (d) velocity sensitive MRA, and (e) arterial spin-labeling MRA.

Multimodality imaging evaluation of arteriovenous fistulas and grafts: a clinical practice review.

Arteriovenous fistulas (AVFs) and grafts (AVGs) are the preferred forms of vascular access for hemodialysis in patients with severe renal dysfunction. Multimodality imaging plays an important role in the pre-procedural evaluation of these patients. Ultrasound is often used for pre-procedural vascular mapping in preparation for the creation of an AVF or AVG.

Magnetic Resonance Safety: Pregnancy and Lactation.

MRI is a powerful diagnostic tool with excellent soft tissue contrast that uses nonionizing radiation. These advantages make MRI an appealing modality for imaging the pregnant patient; however, specific risks inherent to the magnetic resonance environment must be considered. MRI may be performed without and/or with intravenous contrast, which adds further fetal considerations.

Müllerian duct anomalies coincident with endometriosis: a review.

The association between obstructed müllerian duct anomalies and endometriosis has been well established and the pathogenesis is attributed to the theory of retrograde menstruation. However, this relationship with endometriosis is less clear in women with unobstructed müllerian duct anomalies and in those with rudimentary uterine structures that lack functioning endometrial tissue. This article reviews the embryology, genetics, pathophysiology, and American Society for Reproductive Medicine (ASRM) classification for müllerian duct anomalies together with the genetics and pathophysiology of endometriosis to provide a framework for understanding the complex relationship between these two entities.

Imaging Appearance and Nonsurgical Management of Pelvic Venous Congestion Syndrome.

Pelvic venous congestion syndrome (PVCS) is a challenging and complex cause of chronic pelvic pain in female patients. PVCS due to incompetent vein valves is the combination of gonadal vein reflux and pelvic venous engorgement in patients with chronic pelvic pain without other causes. However, pelvic venous engorgement and gonadal vein reflux can be seen in patients without pelvic pain, which makes obtaining a detailed history and physical examination important for workup and diagnosis.

Non-alcoholic fatty liver disease-associated hepatocellular carcinoma: effect of hepatic steatosis on major hepatocellular carcinoma features at MRI.

Objective:: To evaluate the effect of hepatic steatosis on LI-RADS® major features at MRI in patients with non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC).

Methods:: HCC and liver parenchyma features at MRI from 48 consecutive patients with NAFLD and histology proven HCC (mean ± SD; 4.5 ± 3.

MR elastography in primary sclerosing cholangitis: correlating liver stiffness with bile duct strictures and parenchymal changes.

Aim: To determine correlation of liver stiffness measured by MR Elastography (MRE) with biliary abnormalities on MR Cholangiopancreatography (MRCP) and MRI parenchymal features in patients with primary sclerosing cholangitis (PSC).

Methods: Fifty-five patients with PSC who underwent MRI of the liver with MRCP and MRE were retrospectively evaluated. Two board-certified abdominal radiologists in agreement reviewed the MRI, MRCP, and MRE images.

Standardized Approach for ROI-Based Measurements of Proton Density Fat Fraction and R2* in the Liver.

Objective: The purpose of this study was to evaluate the reproducibility (interreviewer agreement) and repeatability (intrareviewer agreement) of ROI sampling strategies to measure chemical shift-encoded (CSE) MRI-based liver proton density fat fraction (PDFF) and R2* (1 / T2*). A secondary purpose was to standardize ROI-based liver PDFF and R2* measurements by providing a compromise between measurement reproducibility and repeatability and time burden for image analysts.

Materials And Methods: CSE data from two cohorts were retrospectively analyzed.

Combined gadoxetic acid and gadofosveset enhanced liver MRI for detection and characterization of liver metastases.

Purpose: To compare gadoxetic acid alone and combined gadoxetic acid/gadofosveset trisodium-enhanced liver MRI for detection of metastases and differentiation of metastases from haemangiomas.

Methods: Ninety-one patients underwent gadoxetic acid-enhanced liver MRI before and after additional injection of gadofosveset. First, two readers retrospectively identified metastases on gadoxetic acid alone enhanced delayed hepatobiliary phase T1-weighted images together with all other MR images (dynamic images, T2-weighted images, diffusion-weighted images).

An Investigation of Transient Severe Motion Related to Gadoxetic Acid-enhanced MR Imaging.

Purpose: To investigate the cause of imaging artifacts observed during gadoxetic acid-enhanced arterial phase imaging of the liver.

Materials And Methods: This HIPAA-compliant study was approved by the institutional review board. Data were collected prospectively at two sites (site A, United States; site B, Japan) from patients undergoing contrast material-enhanced MR imaging with gadoxetic acid (site A, n = 154, dose = 0.

Multiple overlapping k-space junctions for investigating translating objects (MOJITO).

It is a well-known property in Fourier transform magnetic resonance imaging (MRI) that rigid body translational motion in image space results in linear phase accumulation in k -space. This work describes Multiple Overlapping k-space Junctions for Investigating Translating Objects (MOJITO), a correction scheme based on phase differences at trajectory intersections caused by 2-D alterations in the position of an object during MR imaging. The algorithm allows both detection and correction of motion artifacts caused by 2-D rigid body translational motion.

Analysis of signal-to-noise behavior in Cartesian continuous sampling sequences: predictions and experimental validation of opportunities for improved image SNR.

Image signal-to-noise ratio (SNR) limits many MRI applications. Here we propose a method to improve SNR based on continuous sampling (CS) during each TR without significant increases in acquisition time. The general concept of CS is defined here as sampling the NMR signal immediately after slice excitation including ramp times, both the dephase and rephase lobes, the phase-encoding (PE) gradient application, and the slice refocusing gradient.