Ultrasound transmission computed tomography of the breast.

Abstract

A preliminary clinical study of ultrasound transmission computed tomography of the breast (UTCTB) was undertaken to evaluate its capacity in the detection of breast abnormalities and to establish criteria for distinguishing benign from malignant lesions. Only patients with palpable and/or mammographically evident lesions were selected for study; complete analysis was accomplished in 78 cases. Visual and computer interpretations of reconstructed UTCTB scans were based on changes in speed of sound wave transmission and attenuation between the suspicious area and the surrounding tissue. In the computer-aided classification, discriminant functions were derived to predict the presence or absence of carcinoma. Visual analysis was subject to a low sensitivity. The presence of high speed transmission within a lesion usually indicated malignancy, although the converse was not true. Computer-aided preliminary screening of UTCTB scans by a trained technician may have the potential of contributing to interpretation accuracy; however, this finding must be highly qualified, given the methodologic constraints of the study.

Ultrasonographic Evaluation of Hyoid–Larynx Approximation in Dysphagic Stroke Patients

“…Numerous ongoing studies (Kolb et al 2002;Lucas-Fehm 2005) including the large ACRIN study (ACRIN: http://www.acrin.org, 2008) have been aimed at evaluating ultrasound (US) for breast cancer screening. Most of the early experimental work to develop breast ultrasound computed tomography (UCT) was performed in late 70's and early 80's (Greenleafet al, 197480's (Greenleafet al, , 197780's (Greenleafet al, , 198180's (Greenleafet al, ,1987Carson et al 1981;Schreiman et al, 1984;Scherzinger et aI, 1989). Since the early investigators were often hindered by the limited memory and processor speed of their computers, the quality of the reconstruction images was not high enough for clinical use (Jones, 1993).…”

High-resolution imaging without iteration: a fast and robust method for breast ultrasound tomography

“…Knowing the location of the point scatterer we can rearrange (10) to determine the exact scattering potential from a single scattering measurement, i.e.…”

“…The possibility of improving the sensitivity and specificity of sonography has been investigated since the 1970s within the framework of breast Ultrasound Tomography (UST) [8][9][10][11][12][13][14][15] .…”

“…The dominant approach in breast UST is Time-of-Flight Tomography (TFT) 9,10,12,[17][18][19][20][21][22] which applies a ray-based approach to arrival times for transmitted signals in order to produce -either directly in the case of straight rays or with iterations for bent rays -a sound-speed map. This follows the approach in X-ray CT based reconstruction systems which can rely on simple straight ray approximations 23,24 .…”

Acoustic attenuation imaging of tissue bulk properties with a priori information

“…Using the same dataset, traditional pulse echo, attenuation, and speed of sound images can be constructed simultaneously for multi-mode screening. [11][12][13] There are varied approaches to ultrasound attenuation tomography of the breast, encompassing different methods of processing attenuation information given the recorded RF signal. 10,[14][15][16] However, these methods produce attenuation coefficient images that are highly affected by signal losses due to diffraction at boundaries of high sound speed or acoustic impedance change.…”