Alexander Haak

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This work presents experimental responses of single ultrasound contrast agents to short, large amplitude pulses, characterized using double passive cavitation detection. In this technique, two matched, focused receive transducers were aligned orthogonally to capture the acoustic response of a microbubble from within the overlapping confocal region. The(More)
Ultrasonic backscatter is useful for characterizing tissues and several groups have reported methods for estimating backscattering properties. Previous interlaboratory comparisons have been made to test the ability to accurately estimate the backscatter coefficient (BSC) by different laboratories around the world. Results of these comparisons showed(More)
In this communication data on the natural history of euthyroid multinodular goitres are presented. From a total group of 140 patients (mean age 54.6 years, 14 men and 126 women; 88 with autonomous, 52 with non-autonomous function), follow-up data were available for 90 patients (mean age 54.0 years, 11 men and 79 women; 64 with autonomous, 26 with(More)
Applicability of ultrasound phantoms to biological tissue has been limited because most phantoms have generally used strong scatterers. The objective was to develop very weakly scattering phantoms, whose acoustic scattering properties are likely closer to those of tissues and then compare theoretical simulations and experimental backscatter coefficient(More)
OBJECTIVE To translate quantitative ultrasound (QUS) from the laboratory into the clinic, it is necessary to demonstrate that the measurements are platform independent. Because the backscatter coefficient (BSC) is the fundamental estimate from which additional QUS estimates are calculated, agreement between BSC results using different systems must be(More)
OBJECTIVES Ultrasound contrast agents (UCAs) are intravenously infused microbubbles that add definition to ultrasonic images. Ultrasound contrast agents continue to show clinical promise in cardiovascular imaging, but their biological effects are not known with confidence. We used a cholesterol-fed rabbit model to evaluate these effects when used in(More)
Non-small cell lung cancers (NSLC) are aggressive cancers that are insensitive to chemotherapies and accounts for nearly 33% of all cancer deaths in the United States. Two hallmarks of cancer that allow cells to invade and metastasize are sustained proliferation and enhanced motility. In this study we investigate the relationship between urokinase(More)
A 67-yr-old Indonesian patient with disseminated histoplasmosis is described. He had general malaise and fever for 6 months; an oral ulcer, bilateral adrenal gland enlargement and partial adrenal insufficiency were found. An adrenal aspirate contained Histoplasma capsulatum. The literature on adrenal involvement in disseminated histoplasmosis is reviewed(More)