Quantitative myocardial tissue characterization is being developed as an adjunct to conventional echocardiography to delineate the physical state of myocardium under diverse pathophysiological states. Real-time quantitative integrated backscatter imaging has made possible clinical investigations carried out in the United States, Europe, and Japan in patients with ischemic heart disease, hypertrophic cardiomyopathy, and cardiac allograft rejection, among others. A modification of the imaging processing used for characterization of tissue facilitates automatic detection of endocardial blood interfaces and on-line quantification of ventricular size and function, which has been recently introduced in clinical practice.
View Article and Find Full Text PDFThe use of silastic foam as a surgical dressing in 15 children with full thickness burns to the hand is described. Silastic foam is a safe, easy and effective means of dressing the hand following surgery. It is rigid enough to act as a splint, and at the same time is deformable and accommodates postoperative swelling.
View Article and Find Full Text PDFBackground: Direct assessment of left atrial (LA) function has not been previously performed by noninvasive techniques; rather, LA function has been evaluated only indirectly via the analysis of transmitral flow velocity by Doppler. The recent development of real-time two-dimensional echocardiographic automatic boundary detection suggests that LA dimensions can be measured instantaneously to provide on-line assessment of its systolic and diastolic functions.
Methods And Results: We performed echocardiographic assessment of LA dimensions and function with automatic boundary detection in 45 patients by using the apical four-chamber view.
Behavioral science theory has changed greatly since 1978, when Miller's Living Systems was published. Much of the change represents progress, particularly in the biological fields. During that time, living systems theory (LST) developed in many ways.
View Article and Find Full Text PDFUltrasound Med Biol
September 1993
To determine the role of ultrasonic tissue characterization for the detection of changes in myocardial architecture associated with cardiomyopathy, acoustic microscopy was performed on the hearts of 4- to 6-month-old tight-skin mice [TSK/+, C57-B10.D2 (58B)/SN strain], a model of cardiomyopathy characterized by diffuse interstitial fibrosis. Ultrasonic backscatter was measured from excised segments of left ventricular free walls of five TSK mice and five sex- and age-matched normal controls with a 50 MHz broad band focused piezoelectric transducer operated in a saline-filled water tank at room temperature.
View Article and Find Full Text PDFAnisotropy of ultrasonic scattering and attenuation in heart tissue depends on the specific orientation of myofibers with respect to angle of insonification. We used lateral gain compensation (LGC) to correct two-dimensional cardiac images for physiologic anisotropy. Normal hearts excised from three dogs and five pigs were insonified in a water tank with both 2.
View Article and Find Full Text PDFJ Acoust Soc Am
December 1992
Measurements of ultrasonic quasilongitudinal velocity were made in the muscle fiber plane of excised human myocardium. Multiple adjacent planes across the left ventricular wall were interrogated to assess the transmural dependence of velocity. For each measurement plane, data were obtained in 2-deg increments through the full 360 deg relative to the myofibers.
View Article and Find Full Text PDFTo develop an approach for on-line quantification of left ventricular size and function during pharmacological stress testing we employed echocardiographic automatic edge detection via integrated backscatter imaging during dobutamine infusion in 27 patients. Ventricular cavity areas, fractional area change and rate of cavity area change were obtained on-line with instantaneous graphic display of the data. When compared to baseline image data, patients with a normal response exhibited modest (15%) reduction in end-diastolic cavity areas at peak dobutamine level, but marked (33%) reduction in systolic areas yielding a 52% increase in fractional area change (n = 13; P < 0.
View Article and Find Full Text PDFTo provide on-line quantification of left ventricular cavity dimensions and function by echocardiography 60 control subjects and 10 patients with cardiac dysfunction were studied. A novel, ultrasound imaging system was used which was developed to detect and track, in real time, ventricular endocardial blood boundaries based on quantitative assessment of acoustic properties of tissue. In addition, lateral gain compensation, a robust and novel image enhancement procedure, was used to provide instantaneous measurement and display of cavity areas and functional indexes on a beat-by-beat basis within regions of interest drawn around the blood pool cavity.
View Article and Find Full Text PDFKasabach-Merritt syndrome is the association of thrombocytopenia, spontaneous bleeding, and enlargement of a haemangioma. It is caused by an intense, self-perpetuating process of clot-formation and lysis within the abnormal vascular channels of the haemangioma, and results in consumption of platelets and clotting factors. Treatment involves ablation of the lesion with or without pharmacological manipulation of the coagulation and fibrinolytic systems.
View Article and Find Full Text PDFBackground: Noninvasive approaches to the evaluation of idiopathic cardiomyopathy are limited. Recent work from our laboratory has used quantitative ultrasound to define the three-dimensional structure of normal human myocardium and the myocardial remodeling associated with infarction. Our goal was to define the role of ultrasonic tissue characterization for detection of specific alterations in the three-dimensional transmural architecture of idiopathic dilated cardiomyopathy.
View Article and Find Full Text PDFTo determine whether high-frequency ultrasound could distinguish normal from pathological vascular structure and to elucidate the determinants of ultrasonic backscatter in different layers of normal and atherosclerotic arteries, high-resolution acoustic microscopy at 50 MHz was used to characterize aortic plaque in six New Zealand White rabbits fed a 2% cholesterol diet for 3.5 months. Four rabbits were fed a standard diet for 3.
View Article and Find Full Text PDFQuantitative myocardial tissue characterization is being developed to complement and expand conventional echocardiography by delineating the physical state of myocardium under diverse pathophysiologic conditions. Real-time quantitative integrated backscatter imaging has already been applied to patients with ischemic heart disease, hypertrophic cardiomyopathy, and cardiac allograft rejection in clinical investigations performed in the United States, Europe, and Japan. A recently introduced modification of imaging processing algorithms employed for characterization of tissue facilitates automatic detection of endocardial-blood interfaces and on-line quantification of ventricular size and function.
View Article and Find Full Text PDFAn algorithm of fluid resuscitation for cutaneous burns is presented. The management of these cases entails an initial process of evaluation followed, when appropriate, by the administration of intravenous fluids. The fluid requirements are prospectively calculated and subsequently modified by using closed loop feedback with monitoring of urine output, plasma deficit, osmolality and vital signs.
View Article and Find Full Text PDFIt has been reported previously that acute and mature myocardial infarction in dogs can be differentiated in vitro and in vivo by ultrasonic tissue characterization based on measurement of the frequency dependence of ultrasonic backscatter. To characterize human infarction with an index of the frequency dependence of backscatter that could be obtained in patients, cylindrical biopsy specimens from 7 normal regions and 12 regions of infarction of 6 fixed, explanted human hearts in 2-deg steps around their entire circumference with a 5-MHz broadband transducer were insonified. One to six consecutive transmural levels were studied for each specimen.
View Article and Find Full Text PDFAlthough patients with diabetes mellitus may be afflicted by cardiomyopathy, its prevalence and nature are controversial. Studies have shown that fibrosis alters the acoustic properties of the heart in animals and humans and that the changes are detectable by cardiac tissue characterization with ultrasound. The present study was performed to characterize myocardial acoustic properties in patients with insulin-dependent diabetes to determine whether ultrasound tissue characterization could detect changes potentially indicative of occult cardiomyopathy.
View Article and Find Full Text PDFA 2-session study examined Indian and American adults' and children's (N = 140) reasoning about moral dilemmas involving conflicts between interpersonal and justice expectations. Most Indians gave priority to the interpersonal expectations, whereas most Americans gave priority to the justice expectations. Indians tended to categorize their conflict resolutions in moral terms.
View Article and Find Full Text PDFTo provide an approach suitable for on-line analysis of ventricular function, a conventional two-dimensional ultrasound imaging system was modified to detect and track blood-tissue interfaces in real time based on their quantitative acoustic properties. This modification permitted on-line display of the left ventricular cavity area, fractional area change, volumes and ejection fraction on a beat by beat basis. Images were obtained from 54 patients and 12 normal subjects with broad ranges of ventricular dimensions and systolic function.
View Article and Find Full Text PDFBackground: Remodeling of myocardial tissue after infarction may culminate in the development of either a well-healed scar or a thin, expanded heart wall segment that predisposes to ventricular aneurysm formation, congestive heart failure, or ventricular tachycardia. The three-dimensional architecture of mature human infarct tissue and the mechanisms that determine it have not been elucidated. We have previously shown that quantitative ultrasonic backscatter can be used to define the transmural organization of human myofibers in the normal ventricular wall by measuring the dependence of backscatter on the angle of insonification, or ultrasonic anisotropy.
View Article and Find Full Text PDFWe have previously shown that ultrasonic tissue characterization with two-dimensional (2D) guided M-Mode acquisition of integrated backscatter (IB) identifies ischemic and infarcted myocardium. However, there is no information regarding the applicability of IB in assessment of right ventricular (RV) myocardial acoustic properties. Thus, we performed IB imaging of the RV in a group of 45 consecutive patients and were successful in 16, all of whom had normal RV wall motion.
View Article and Find Full Text PDFThis article suggests that the adversarial approach of the criminal justice system towards handling of the paraphilias ultimately does more harm than good. The acceptance by helping professionals of the criminal justice model into their diagnostic consideration and treatment procedures is discussed, along with a discussion of some of the debilitating ethical and scientific implications of such an alignment. Historical, political and professional factors which have contributed to these disturbing trends are discussed and proposals are made as to how helping professionals might reclaim and reassert their traditional roles in service of their clientele.
View Article and Find Full Text PDFProc Annu Symp Comput Appl Med Care
February 1993
Proc Annu Symp Comput Appl Med Care
February 1993
ATLAS-plus [Advanced Tools for Learning Anatomical Structure] is a multimedia program used to assist in the teaching of anatomy at the University of Michigan Medical School. ATLAS-plus contains three courses: Histology, Embryology, and Gross Anatomy. In addition to the three courses, a glossary containing terms from the three courses is available.
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