Journal article
Visual and quantitative evaluation of selected image combination schemes in ultrasound spatial compound scanning
Multi-angle spatial compound images are normally generated by averaging the recorded single-angle images (SAIs). To exploit possible advantages associated with alternative combination schemes, this paper investigates both the effect of number of angles (Ntheta) as well as operator (mean, median, mean-excluding-maximum (mem), root-mean-square (rms), geometric mean and maximum) on image quality (tissue delineation and artifacts), speckle signal-to-noise ratio (SNRs) and contrast.
The evaluation is based on in vitro SAI (+/-21degrees in steps of Deltatheta = 7degrees) of formalin fixed porcine tissue containing adipose, connective and muscular tissue. Image quality increased with number of angles up to +/-14degrees after which the improvements became debatable. The mem and median operators, which try to render the images more quantitatively correct by suppressing strong echoes from specular reflectors, provide some improvement in this regard.
When combining the SAI with the mean operator, the SNRs increases-in general-with N-theta. For N-theta = 2, the SNRs increases with Deltatheta as expected. When N-theta = 7, the highest SNRs is obtained for the mem, rms, and geometric mean operators, while the lowest SNRs is obtained for the maximum operator.
When comparing SNRs for adipose and fibrous tissue, the level is close to 1.91 for adipose tissue but only 1.7 for fibrous tissue which contain relatively few organized scattering structures.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2004 |
| Pages: | 181-190 |
| ISSN: | 1558254x and 02780062 |
| Types: | Journal article |
| DOI: | 10.1109/TMI.2003.822824 |
| ORCIDs: | Wilhjelm, Jens E. |
Anatomy compound operators contrast histology spatial compound ultrasound speckle signal-to-noise ratio
Adipose Tissue Algorithms Animals Arteriosclerosis Biological materials Connective Tissue Image Enhancement Image Interpretation, Computer-Assisted Image generation Image quality Imaging, Three-Dimensional In Vitro Techniques In vitro Muscle, Skeletal Rendering (computer graphics) Reproducibility of Results Sensitivity and Specificity Signal to noise ratio Speckle Subtraction Technique Swine Ultrasonic imaging Ultrasonic transducers Ultrasonography adipose tissue biological tissues biomedical ultrasonics connective tissue geometric mean operator image quality maximum operator mean operator mean-excluding-maximum operator median operator medical image processing multiangle spatial compound images muscular tissue organized scattering structures quantitative evaluation recorded single-angle images root-mean-square operator selected image combination schemes specular reflectors strong echoes suppression tissue delineation ultrasound spatial compound scanning visual evaluation
