In Vivo Ultrasound Biomicroscopy of Skin: Spectral System Characteristics and Inverse Filtering Optimization

High-frequency ultrasound (HFUS) in the 20 MHz to 100 MHz range has to meet the opposite requirements of good spatial resolution and of high penetration depth for in vivo ultrasound biomicroscopy (UBM) of skin. The attenuation of water, which serves as sound propagation medium between utilized singl...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on ultrasonics, ferroelectrics, and frequency control ferroelectrics, and frequency control, 2007-08, Vol.54 (8), p.1551-1559
Main Authors: Vogt, M., Ermert, H.
Format: Article
Language:English
Subjects:
Acoustic propagation
Attenuation
Biomedical materials
Filtering
Filtration
Frequency
Humans
Image Interpretation, Computer-Assisted
Imaging
In vivo
In vivo testing
In vivo tests
Melanoma - diagnostic imaging
Microscopy, Acoustic
Phantoms, Imaging
Pulse measurements
RF signals
Signal Processing, Computer-Assisted
Skin
Skin Neoplasms - diagnostic imaging
Spatial resolution
Spectra
Studies
Surgical implants
Transducers
Ultrasonic imaging
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:High-frequency ultrasound (HFUS) in the 20 MHz to 100 MHz range has to meet the opposite requirements of good spatial resolution and of high penetration depth for in vivo ultrasound biomicroscopy (UBM) of skin. The attenuation of water, which serves as sound propagation medium between utilized single clement transducers and the skin, becomes very eminent with increasing frequency. Furthermore, the spectra of acquired radio frequency (rf) echo signals change over depth because of the diffracted sound field characteristics. The reduction of the system's center frequency and bandwidth causes a significant loss of spatial resolution over depth. In this paper, the spectral characteristics of HFUS imaging systems and the potential of inverse echo signal filtering for the optimization of pulse-echo measurements is analyzed and validated. A Gaussian model of the system's transfer function, which takes into account the frequency-dependent attenuation of the water path, was developed. Predictions of system performance are derived from this model and compared with measurement results. The design of a HFUS skin imaging system with a 100 MHz range transducer and a broadband driving electronics is discussed. A time-variant filter for inverse rf echo signal filtering was designed to compensate the system's depth-dependent imaging properties. Results of in vivo measurements are shown and discussed.
ISSN:0885-3010
1525-8955
DOI:10.1109/TUFFC.2007.425