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Diagnostic ultrasound ( PDFDrive )

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APPENDIX Ultrasound Artifacts: A Virtual Chapter

e33

Spectral Broadening

Spectral broadening occurs when there are multiple diferent

velocities of low within a vessel. his can be a sign of stenosis.

However, artifactual spectral broadening can occur owing

to improper positioning of the sample volume near the vessel

wall, use of an excessively large sample volume, or excessive

system gain.

FIG. A.63 Spectral Broadening. True spectral broadening due to

ECA stenosis. 6 (See Chapter 26, Fig. 26.18.)

FIG. A.62 Spectral Broadening. The range of velocities detected

at a given time in the pulse cycle is relected in the Doppler spectrum

as spectral broadening. (A) Normal spectrum. Spectral broadening may

arise from turbulent low in association with vessel stenosis. (B and C)

Artifactual spectral broadening may be produced by improper positioning

of the sample volume near the vessel wall, use of an excessively

large sample volume (B), or excessive system gain (C). 2 (See Chapter

1, Fig. 1.45.)

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