Heavy metal mapping, source identification, and ecological risk assessment in the International Hamoun wetland, Sistan region, Iran.

This study is aimed at assessing the ecological risk of heavy metals (HMs) in the International Hamoun wetland, southeastern Iran. Twenty sediment samples were collected from the wetland surface for geochemical analysis of 23 HMs. The inverse distance weighting (IDW) technique was used to map the HMs.

Assessment of subendocardial vs. subepicardial left ventricular twist using tagged MRI images.

Objective: The objective of this study is to determine the normal value of 3D left ventricular (LV) twist in subendocardial, mid-wall and subepicardial layers, as well as to study the effects of aging on 3D LV twist by tagged MR motion tracking techniques. Three dimensional motion detection based on 3D tagged MR images is robust to out-of-plane motion error; while 2D motion detection is inherently unable to analyze the 3D cardiac motion and may lead to inaccurate results.

Methods: The 3D LV volumetric images were acquired in 52 normal adult subjects (aged 21-82) and were analyzed by using 3D HARmonic phase (HARP) technique.

Tissue Doppler imaging optical flow (TDIOF): a combined B-mode and tissue Doppler approach for cardiac motion estimation in echocardiographic images.

The quantitative analysis of cardiac motion from echocardiographic images helps clinicians in the diagnosis and therapy of patients suffering from heart disease. Quantitative analysis is usually based on tissue Doppler imaging (TDI) or speckle tracking. These methods are based on two techniques which to a large degree are independent: the Doppler phenomenon and image sequence processing.

Cardiac motion and strain detection using 4D CT images: comparison with tagged MRI, and echocardiography.

Ischemic heart disease is a leading cause of death in the modern world. Coronary obstruction is the basis for ischemic heart disease and leads to decreased cardiac supply and decreased contractility of the myocardium. Recently, high quality 4D computed tomography (CT) has become available for cardiac imaging and provides the clinician with high quality anatomical images.

Assessment of age-related changes in left ventricular twist by 3-dimensional speckle-tracking echocardiography.

Objectives: The purpose of this study was to determine the normal value of left ventricular (LV) twist in 3-dimensional (3D) geometry and to study the effects of aging on 3D LV twist by sophisticated newly developed 3D speckle-tracking echocardiographic techniques.

Methods: Recent developments in miniaturized ultrasound arrays have provided us with high-quality 3D echocardiographic data. Speckle tracking based on 3D images is robust to out-of-plane motion error, whereas 2-dimensional speckle tracking is inherently unable to analyze 3D cardiac motion and may lead to measurement inaccuracies.

A biventricular multimodal (MRI/ultrasound) cardiac phantom.

A cardiac phantom can be of crucial importance in the development and validation of ultrasound and cardiac magnetic resonance (MR) imaging and image analysis methods. A biventricular multimodal cardiac phantom has been manufactured in-house that can simulate normal and pathologic hearts with different degrees of infarction. The two-chamber structure can simulate the asymmetric left ventricular motion.

A fast and accurate method for arrhythmia detection.

Electrocardiography is the method of choice for cardiac electrophysiological evaluation. Arrhythmia is one of the most crucial problems in cardiology. So far, many methods have been developed for arrhythmia detection, recognition and classification.

Optimized noninvasive monitoring of thermal changes on digital B-mode renal sonography during revascularization therapy.

Objective: Noninvasive real-time thermal change monitoring of human internal organs can play a critical role in diagnosis and treatment of many disorders, including reperfusion of renal arteries during anticoagulation therapy.

Methods: This article focuses on tissue temperature detection using ultrasound velocity changes in different structures and their related speckle shift from their primary locations on high-quality B-mode digital sonography. We evaluated different speckle-tracking techniques and optimized them using appropriate motion estimation methods to determine the best algorithm and parameters.

Ultrasound thermal change detection based on steerable filters.

Growing tendency toward utilization of Laser and RF knives has opened a new port for thermal control applications in which ultrasound thermal detection is crucial. Ultrasound velocity is dependent on the thermal properties of the environment. In this paper we focus on tissue temperature detection using multiresolution steerable filter-based motion estimation.

FPGA-core defibrillator using wavelet-fuzzy ECG arrhythmia classification.

An electrocardiogram (ECG) feature extraction and classification system has been developed and evaluated using Quartus II 7.1 belong to Altera Ltd. In wavelet domain QRS complexes were detected and each complex was used to locate the peaks of the individual waves.

A new variational technique for combining affine registration and optical flow in echocardiography images.

Since myocardial motion is directly related to cardiac vascular supply, it can be helpful in diagnosing the heart abnormalities. The most comprehensive and available imaging study of the cardiac function is B-Mode echocardiography. However diagnostic systems are expert dependent and motion is not clear in the B-mode echocardiography images and therefore many efforts are pointed toward proposing new methods to measure the motion accurately.

An efficient temperature estimation using optical-flow in ultrasound B-mode digital images.

A two-dimensional temperature estimation method has been proposed based on the detection of shifts in speckle pattern location of ultrasound B-Mode digital images from a region of tissue undergoing thermal therapy. The speckle pattern shifts were due to the local temperature dependence of sound speed and thermal expansion in the heated region. Here in this paper we made use of optical-flow in order to achieve a better accuracy and lower computational burden.