Myocardial Extracellular Volume Fraction Adds Prognostic Information Beyond Myocardial Replacement Fibrosis.

Background: Cardiac magnetic resonance techniques permit quantification of the myocardial extracellular volume fraction (ECV), representing a surrogate marker of reactive interstitial fibrosis, and late gadolinium enhancement (LGE), representing replacement fibrosis or scar. ECV and LGE have been independently linked with heart failure (HF) events. In deriving ECV, coronary artery disease type LGE, but not non-coronary artery disease type LGE, has been consistently excluded.

Four-dimensional flow cardiovascular magnetic resonance in aortic dissection: Assessment in an ex vivo model and preliminary clinical experience.

Objective: Four-dimensional flow cardiovascular magnetic resonance may improve assessment of hemodynamics in patients with aortic dissection. The purpose of this study was to evaluate the feasibility and accuracy of 4-dimensional flow cardiovascular magnetic resonance assessment of true and false lumens flow.

Methods: Thirteen ex vivo porcine aortic dissection models were mounted to a flow loop.

Left ventricular function in patients with hypertrophic cardiomyopathy and its relation to myocardial fibrosis and exercise tolerance.

We sought to determine the relation between myocardial extracellular volume (ECV), left ventricular (LV) diastolic function, and exercise tolerance in patients with hypertrophic cardiomyopathy (HCM). Forty five HCM patients with an ejection fraction >50% and no previous septal reduction therapy underwent imaging by CMR and transthoracic echocardiography. CMR was used to quantify LV volumes, mass, EF, LA volumes, scar burden, pre and post contrast T1 relaxation times and ECV.

Detection of LA and LAA Thrombus by CMR in Patients Referred for Pulmonary Vein Isolation.

Objectives: The goal of this study was to evaluate the diagnostic performance of a comprehensive, multicomponent cardiac magnetic resonance (CMR) study for assessment of left atrial (LA) and left atrial appendage (LAA) thrombus.

Background: Pre-operative evaluation for pulmonary vein isolation (PVI) typically requires tomographic imaging to define pulmonary venous anatomy and transesophageal echocardiogram (TEE) to assess for the presence of LA/LAA thrombus. CMR is increasingly being used to define pulmonary venous anatomy before PVI.

Important advances in technology and unique applications related to cardiac magnetic resonance imaging.

Cardiac magnetic resonance has become a well-established imaging modality and is considered the gold standard for myocardial tissue viability assessment and ventricular volumes quantification. Recent technological hardware and software advancements in magnetic resonance imaging technology have allowed the development of new methods that can improve clinical cardiovascular diagnosis and prognosis. The advent of a new generation of higher magnetic field scanners can be beneficial to various clinical applications.

ASSESSMENT OF TISSUE OPTICAL CLEARING AS A FUNCTION OF GLUCOSE CONCENTRATION USING OPTICAL COHERENCE TOMOGRAPHY.

One of the major challenges in imaging biological tissues using optical techniques, such as optical coherence tomography (OCT), is the lack of light penetration due to highly turbid structures within the tissue. Optical clearing techniques enable the biological samples to be more optically homogeneous, allowing for deeper penetration of light into the tissue. This study investigates the effect of optical clearing utilizing various concentrations of glucose solution (10%, 30%, and 50%) on porcine skin.

Monitoring of glucose permeability in monkey skin in vivo using Optical Coherence Tomography.

Topical trans-dermal delivery of drugs has proven to be a promising route for treatment of many dermatological diseases. The aim of this study is to monitor and quantify the permeability rate of glucose solutions in rhesus monkey skin noninvasively in vivo as a primate model for drug diffusion. A time-domain Optical Coherence Tomography (OCT) system was used to image the diffusion of glucose in the skin of anesthetized monkeys for which the permeability rate was calculated.

Effect of temperature on permeation of low-density lipoprotein particles through human carotid artery tissues.

Quantification of the diffusion of small molecules and large lipid transporting lipoproteins across arterial tissues could be useful in elucidating the mechanism(s) of atherosclerosis. Optical coherence tomography (OCT) was used to determine the effect of temperature on the rate of diffusion of glucose and low-density lipoproteins (LDL) in human carotid endarterectomy tissue in vitro. The permeability rate for glucose was calculated to be (3.

Differential permeability rate and percent clearing of glucose in different regions in rabbit sclera.

Imaging of biological tissues with optical coherence tomography (OCT) poses a great interest for its capability to noninvasively outline subsurface microstructures within tissues. However, a major limitation for many optical imaging techniques is inadequate depth penetration of light in turbid media, which is bounded to just a few millimeters. There have been several attempts to improve light penetration depth in biological tissues, including application of different tissue optical clearing methods.

Permeability of hyperosmotic agent in normal and atherosclerotic vascular tissues.

Noninvasive cardiovascular imaging could lead to the early detection and timely treatment of complex atherosclerotic lesions responsible for major cardiovascular events. Recent investigations have suggested that optical coherence tomography (OCT) is an ideal diagnostic tool due to the high resolution this technology achieves in discriminating the different features of atherosclerotic lesions based on structural imaging. We explore the capability of OCT for functional imaging of normal and atherosclerotic aortic tissues based on time- and depth-resolved quantification of the permeability of biomolecules through these tissues.

Nondestructive quantification of analyte diffusion in cornea and sclera using optical coherence tomography.

Purpose: Noninvasive functional imaging, monitoring, and quantification of analytes transport in epithelial ocular tissues are extremely important for therapy and diagnostics of many eye diseases. In this study the authors investigated the capability of optical coherence tomography (OCT) for noninvasive monitoring and quantification of diffusion of different analytes in sclera and cornea of rabbit eyes.

Methods: A portable time-domain OCT system with wavelength of 1310 +/- 15 nm, output power of 3.

Depth-resolved monitoring of glucose diffusion in tissues by using optical coherence tomography.

We demonstrate the capability of the optical coherence tomography (OCT) technique for depth-resolved monitoring and quantifying of glucose diffusion in fibrous tissues (sclera). The depth-resolved and average permeability coefficients of glucose were calculated. We found that the glucose diffusion rate is not uniform throughout the tissue and is increased from approximately 2.