Prostate cancer (PCa) is diagnosed by means of needle biopsies typically guided by transrectalultrasound (TRUS). TRUS provides an inexpensive and effective means of visualizing gland anatomy and systematically directing each biopsy needle to a specific region within the gland. However, identification of cancerous regions in the prostate cannot be performed reliably using TRUS imaging or any oth...

Lasers provide a non-contact and remote inspection method with high resolution and sensitivity. As a crack detection tool, laser ultrasonics can be used to image surface-breaking cracks with microscopic precision. By monitoring the local elastic scattering conditions and dynamic motion fields present in the immediate vicinity of a surface-breaking crack site, the local crack morphology can be m...

Owing to the successful use of phased array probes in automatic testing machines, more and more applications can now be found in the field of manual inspections. Miniaturization of electronic components and improvements of processing speed allow the integration of phased array hardware into a small, battery driven instruments for fast ultrasonic imaging. The advantages of the phased array techn...

dynamic ranges in excess of 100 dB are attainable in pulseecho operation using commercially available discrete mmponents. Transmission experiments through aluminum and composite plates verify more than 100 dB dynamic range and demonstrate the ability of cMUTs to image defects in air at 2.5 MHz. W e also present a variation on cMUT design which improves the useful bandwidth of the device, permit...

This work describes the development of a new 3D ultrasonic imaging method that combines different beamforming techniques (Phased Array -PAand Synthetic Aperture Focusing Technique -SAFT-). The proposed methodology uses a silicone mask along the x-axis to produce a wide beam in the array width direction (y-axis). Then, a coherent-spatial composition of several phased array B-scan images is imple...

Guided wave imaging with a sparse array of inexpensive transducers offers a fast, reliable, and cost-efficient means for damage detection and localization in plate-like structures such as aircraft and spacecraft skins. As such, this technology is a natural choice for inclusion in condition-based maintenance and integrated structural health management programs. One of the implementation challeng...

Analysis of array data from acoustic scattering in a random medium with a small number of isolated targets is performed in order to image and, thereby, localize the spatial position of each target. Because the host medium has random fluctuations in wave speed, the background medium is itself a source of scattered energy. It is assumed, however, that the targets are sufficiently larger and/or mo...

This article addresses several implementation issues in ultrasonic flow imaging. We discuss frequency-dependent scattering and attenuation, use of interpolation for computation intensive methods and implications of the use of chirps to increase bandwidth. We also discuss wall filtering issues; our observations show that the butterfly search estimator may be capable of detecting flow in the vici...

Ultrasonic imaging of " flesh and blood " is vulnerable to the natural variability of these media: the speed of sound is not known, not constant, and not amenable to calibration using simply shaped manufactured samples. When images of high dimensional accuracy are needed, as for image-guided surgery, the " average " or " typical " values used in diagnostic ultrasound may not be good enough. In ...

Ultrasound imaging is the most commonly used imaging system in medical field. Main problem related to this imaging technique is introduction of speckle noise, thus making the image unclear. The success of ultrasonic examination depends on the image quality which is usually retarded due to speckle noise. There have been several techniques for effective suppression of speckle noise present in ult...