Bioacoustics Research Lab
University of Illinois at Urbana-Champaign | Department of Electrical and Computer Engineering | Department of Bioengineering
Department of Statistics | Coordinated Science Laboratory | Beckman Institute | Food Science and Human Nutrition | Division of Nutritional Sciences | College of Engineering
 Friday, March 29th, 2024
BRL Home
About BRL
Publications
Projects
People
History
Facilities
Abstracts Database
Seminars
Downloads
Archives
Bioengineering Research Partnership
William D. O'Brien, Jr. publications:

Michael L. Oelze publications:

Aiguo Han publications:

BRL Abstracts Database

Search - a quick way to search the entire Abstracts Database.
 
Advanced Search - search specific fields within the Abstracts Database.
Title
Author
Journal
Volume
Year
Abstract Text
Sort by:     Title     Author     Journal     Year
Number of records to return:     10     20     30     50

Your search for ultrasound produced 3296 results.

Page 4 out of 330

Title A brief provocative statement on ultrasound bioeffects.
Author Dunn F.
Journal Ultrasound Med Biol
Volume
Year 1983
Abstract No abstract available.


Title A cavitation and free radical dosimeter for ultrasound.
Author McLean JR, Mortimer AJ.
Journal Ultrasound Med Biol
Volume
Year 1988
Abstract A simple and sensitive method is described for measuring the number of hydroxyl radicals (*OH) produced in aqueous solution by high intensity ultrasound (US). The method is based on the conversion of nonfluorescent terephthalic acid (TA) to highly fluorescent hydroxyterephthalate (HTA). The spectrofluorimeter is calibrated by use of a TA solution which has been exposed to a reference dose of cobalt-60. This allows fluorescence readings produced b ultrasound to be read directly in equivalent centiGrays (cGy). The limit of detection for OH is about 1.3X10(-9) M (equivalent to an exposure of about 0.5 cGy of cobalt ?60). The threshold for transient cavitation (TC) in an air-saturated aqueous solution was found at 0.7 watts per cm(2). Cavitations was consistently produced when TA was exposed in a soft vinyl chamber and only when the chamber was being rotated about an axis which was perpendicular to the US beam. The use of TA as a quantitative indicator of transient cavitation should be of value to the study of ultrasonic biological effects and dosimetry.


Title A characterization of wavefront distortion for analysis of ultrasound diffraction measurements made through an inhomogeneous medium.
Author Waag RC, Astheimer JP, Swartout GW Jr.
Journal IEEE Trans Sonics Ultrason
Volume
Year 1985
Abstract A three-dimensional model of scattering which describes the scattered wave amplitude in terms of a Fourier transform of wave speed variations within a scattering volume has been extended to characterize a form of wavefront distortion by an inhomogeneous intervening medium. The analysis assumed that the phase of the wavefront is perturbed by the medium prior to illuminating the scattering region and also by the medium during propagation from the scattering region to the point of observation. Then the Fourier transform expression for the scattered wave amplitude contains a phase factor, i.e. distortion function, that weights the medium speed variations. The analysis also modifies the Fourier transform relation that exists between the mean square value of the scattered wave amplitude and the correlation function of the medium speed variations. The results includes a weighting of the correlation function of the medium variations by the correlation function of phase transmission to and from the scattering region. Diffraction patterns of a regular array of dots with a Gaussian amplitude weighting are calculated for sinusoidal and for Gaussian phase distortion limited to the incident wave. This limitation permits the distortion to be transferred to the diffracting object and allows a Fourier transform implementation of the diffraction calculation. The calculated results agree with theoretical predictions and demonstrate the effects of two classes of wavefront distortion functions on the observation of diffraction for an improved understanding of scattering measurements when an inhomogeneous medium surrounds the scattering region.


Title A chirp z-transform algorithm for processing doppler ultrasound flowmetry signals.
Author Delk AK.
Journal Thesis(MS): Univ of Illinois
Volume
Year 1982
Abstract No abstract available.


Title A clinical evaluation of contrast-detail analysis for ultrasound images.
Author Lopez H, Loew MH, Butler PF, Hill MC, Allman RM.
Journal Med Phys
Volume
Year 1990
Abstract We report on the reproducibility of human observers' vanishing detection thresholds for visual targets in contrast-detail (C/D) analysis of ultrasound B-mode images. The images used in this study contain visual targets which are circular cross sections of constant-contrast conical structures in the C/D phantom. The vanishing threshold diameters for these targets vary as a function of the perceived size of the imaged target, target-to-background contrast, image noise content, and reproducibility of the decision levels of human observers for repeated observations. Our study indicates that the determination of absolute vanishing threshold diameter values for several targets of different contrast by human observers yields a high degree of error that is not predicted by existing theoretical assumptions based on a static threshold detector. We find that systematic error is introduced by the observers during the course of the experiment and that the levels of sensitivity of the observers differ widely at all times, and increase the amount of total observer error. These results suggest that, due to the large total observer error, C/D analysis may be impractical in a clinical environment, unless there is access to a team of observers specifically and extensively trained in this task. We suggest that a computer-based observer may be more reliable for the objective performance of contrast-detail analysis as a method for evaluating ultrasound image quality and comparison of imaging systems.


Title A clinical evaluation of grey-scale ultrasonography.
Author Taylor KJW, McCready VR.
Journal Br J Radiol
Volume
Year 1976
Abstract Recent technical improvements in grey-scale ultrasound imaging have resulted in the visualization of the internal consistency of soft tissues. This permits the diagnosis of diffuse pathology and detection of small space-occupying lesions. The new technique can be used with advantage in the currently accepted obstetrical applications for ultrasound imaging as well as for new non-obstetrical applications. The method has been found to be a most informative, non-intrusive means for investigating hepatobiliary disease and for the differential diagnosis of chronic splenomegaly.


Title A clinical, noninvasive, MR imaging-monitored ultrasound surgery method.
Author Hynynen K, Freund WR, Cline HE, Chung AH, Watkins RD, Vetro JP, Jolesz FA.
Journal Radiographics
Volume
Year 1996
Abstract A noninvasive method of tissue ablation that is guided and monitored with magnetic resonance (MR) imaging has been developed. The method uses sharply focused ultrasound transducers of different focal lengths to induce a localized temperature elevation during a short exposure (1-20 seconds). A hydraulic, computer-controlled positioning device moves the transducer in an MR imager. The positioner is built into a standard cradle in the imager. The system includes cavitation detection and power monitoring circuitry for patient safety. The target volume is outlined with cross-sectional MR images obtained immediately before sonication. By means of the software, the focus is moved to ablate the volume defined with the images. The temperature elevation during the exposure is monitored by means of the proton resonance frequency shift with fast gradient-echo sequences, and the necrosed volume is demonstrated with T2-weighted fast spin-echo images. This method has been extensively tested in in vivo animal experiments and is now undergoing clinical trial.


Title A combined clinical and research approach to the problem of ultrasound visualization of breast.
Author Kelly-Fry E, Fry FJ, Sanghvi NT, Heimburger RF.
Journal J Ultrasound Med
Volume
Year 1975
Abstract No abstract available.


Title A comparison of 424 carotid bifurcations examined by angiography and the doppler echoflow.
Author White DN, Curry GR.
Journal Ultrasound Med
Volume
Year 1978
Abstract No abstract available.


Title A comparison of AIUM/NEMA thermal indices with calculated temperature rises for a simple third-trimester pregnancy tissue model.
Author Jago JR, Henderson J, Whittingham TA, Mitchell G.
Journal Ultrasound Med Biol
Volume
Year 1999
Abstract Temperature rises due to diagnostic ultrasound exposures have been calculated for a simple third-trimester pregnancy tissue.model. This consisted of a layer of soft tissue representing the abdominal/uterine wall, a layer of liquid and a layer of fetal bone..The ultrasound field parameter used in the calculations was the temporal average of the square of the acoustic pressure (p2TA),.measured in water but corrected for attenuation in the tissue model. The three-dimensional (3-D) distribution of p2TA was.measured for five probes operating in B-mode, and four probes operating in pulsed Doppler and color flow imaging modes. The.calculated temperature rises were compared to the AIUM/NEMA-defined thermal indices appropriate to third-trimester scanning..In B-mode, the ratio of calculated temperature rise to thermal index varied between 0.62 and 1.25, with calculated temperature.rises as high as 1.4 degrees C. In color-flow imaging mode, this ratio varied between 1.26 and 2.45 and, in pulsed Doppler mode,.between 1.46 and 2.92, with calculated temperature rises as high as 1.8 degrees C and 5.8 degrees C, respectively. These results.indicate that, for scanning situations where bone is insonated through an overlying low attenuation liquid layer, the thermal index.may substantially underestimate the maximum temperature rise that could occur.


Page 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73 | 74 | 75 | 76 | 77 | 78 | 79 | 80 | 81 | 82 | 83 | 84 | 85 | 86 | 87 | 88 | 89 | 90 | 91 | 92 | 93 | 94 | 95 | 96 | 97 | 98 | 99 | 100 | 101 | 102 | 103 | 104 | 105 | 106 | 107 | 108 | 109 | 110 | 111 | 112 | 113 | 114 | 115 | 116 | 117 | 118 | 119 | 120 | 121 | 122 | 123 | 124 | 125 | 126 | 127 | 128 | 129 | 130 | 131 | 132 | 133 | 134 | 135 | 136 | 137 | 138 | 139 | 140 | 141 | 142 | 143 | 144 | 145 | 146 | 147 | 148 | 149 | 150 | 151 | 152 | 153 | 154 | 155 | 156 | 157 | 158 | 159 | 160 | 161 | 162 | 163 | 164 | 165 | 166 | 167 | 168 | 169 | 170 | 171 | 172 | 173 | 174 | 175 | 176 | 177 | 178 | 179 | 180 | 181 | 182 | 183 | 184 | 185 | 186 | 187 | 188 | 189 | 190 | 191 | 192 | 193 | 194 | 195 | 196 | 197 | 198 | 199 | 200 | 201 | 202 | 203 | 204 | 205 | 206 | 207 | 208 | 209 | 210 | 211 | 212 | 213 | 214 | 215 | 216 | 217 | 218 | 219 | 220 | 221 | 222 | 223 | 224 | 225 | 226 | 227 | 228 | 229 | 230 | 231 | 232 | 233 | 234 | 235 | 236 | 237 | 238 | 239 | 240 | 241 | 242 | 243 | 244 | 245 | 246 | 247 | 248 | 249 | 250 | 251 | 252 | 253 | 254 | 255 | 256 | 257 | 258 | 259 | 260 | 261 | 262 | 263 | 264 | 265 | 266 | 267 | 268 | 269 | 270 | 271 | 272 | 273 | 274 | 275 | 276 | 277 | 278 | 279 | 280 | 281 | 282 | 283 | 284 | 285 | 286 | 287 | 288 | 289 | 290 | 291 | 292 | 293 | 294 | 295 | 296 | 297 | 298 | 299 | 300 | 301 | 302 | 303 | 304 | 305 | 306 | 307 | 308 | 309 | 310 | 311 | 312 | 313 | 314 | 315 | 316 | 317 | 318 | 319 | 320 | 321 | 322 | 323 | 324 | 325 | 326 | 327 | 328 | 329 | 330