BACKGROUND AND PURPOSE Color-coded perfusion maps can be calculated from ultrasound harmonic gray-scale imaging data to analyze brain tissue perfusion. METHODS In 13 healthy volunteers, 2 doses (0.5 and 1.5 mL) of Optison, a perfluoropropane-containing ultrasound contrast agent, were injected intravenously, and they produced a strong increase in echo enhancement in the brain parenchyma. The c...

background: iron-mediated cardiomyopathy is the main complication of thalassemia major (tm) patients. therefore, there is an important clinical need in the early diagnosis and risk stratification of patients. the aim of this study was to evaluate the efficacy of tissue doppler imaging (tdi) to study cardiac iron overload in patients with tm using t2* magnetic resonance (mr) as the gold-standard...

background: considering suggested formula in the references and pcwp measured by catheterism, in the present study the relation between pulmonary capillary wedge pressure (pcwp) measured the flow velocity of mitral valve and mitral annulus motion through tissue doppler imaging is evaluated methods: 52 cases of severe ms were admitted for balloon mitral valvolotomy (bmv) are included in this stu...

background abnormalities in the velocity and pattern of myocardial shortening on tissue doppler imaging (tdi) have been proposed to aid in the noninvasive diagnosis of coronary artery disease (cad). objectives we investigated the diagnostic value of post-systolic shortening (pss), a delayed ejection velocity of the myocardium after the closure of the aortic valve, on tdi in the diagnosis of cad...

background haemorrhoids are cushions of submucosal vascular tissue located in the anal canal starting just distal to the dentate line. haemorrhoidal disease is a common anorectal disorder which has symptoms of bleeding, prolapse, pain, thrombosis, mucus discharge, and pruritus. haemorrhoidectomy is one of most frequently performed anorectal operation worldwide. objectives the aim of this study ...

A new estimator, Bandwidth Imaging, related to the bandwidth of the ultrasound Doppler signal is proposed as a classification function of blood and tissue signal in transthoracial echocardiography of the left ventricle. An in vivo experiment is presented, where the apparent error rate of Bandwidth Imaging is compared with the apparent error rate of Second-Harmonic Imaging on 15 healthy men. The...

PURPOSE The purpose of this study was to evaluate the ability of second-harmonic imaging to identify differences in corneal stromal collagen organization between normal human and keratoconus corneas. METHODS Six normal corneas from eye bank donors and 13 corneas of patients with keratoconus, obtained after penetrating keratoplasty were examined. A femtosecond titanium-sapphire laser with 800-...

Ultrasound imaging systems usually work in open loop. The system control is thus a sine wave whose frequency is often fixed around two-thirds of the center frequency of the transducer in tissue harmonic imaging. However, this choice requires a knowledge of the transducer and does not take into account the medium properties. Our aim is to seek the command which maximizes the tissue harmonic cont...

Standard methods to characterize patient tissue rely on histology. This technique provides only anatomical information, so complementary imaging methods could provide beneficial phenotypic information. Cancer cells exhibit altered metabolism, and metabolic imaging could be applied to better understand cancer tissue. This study applies redox ratio, fluorescence lifetime, and second harmonic gene...

In medical ultrasound, fundamental imaging (FI) uses the reflected echoes from the same spectral band as that of the emitted pulse. The transmission frequency determines the trade-off between penetration depth and spatial resolution. Tissue harmonic imaging (THI) employs the second harmonic of the emitted frequency band to construct images. Recently, superharmonic imaging (SHI) has been introdu...