Influence of gain adjustment on 3-dimensional power Doppler indices and on spatiotemporal image correlation volumetric pulsatility indices using a flow phantom.
J Ultrasound Med
; 32(10): 1831-6, 2013 Oct.
Article
em En
| MEDLINE
| ID: mdl-24065264
ABSTRACT
Spatiotemporal image correlation can be used to acquire 3-dimensional power Doppler information across a single cardiac cycle. Assessment and comparison of the systolic and diastolic components of the data sets allow measurement of the recently introduced "volumetric pulsatility index" (vPI) through algorithms comparable with those used in 2-dimensional Doppler waveform analysis. The vPI could potentially overcome the dependency on certain machine settings, such as power, color gain, pulse repetition frequency, and attenuation, since these factors would affect the power Doppler signal equally throughout the cardiac cycle. The objective of this study was to compare the effect of color gain on the vascularization index (VI), vascularization-flow index (VFI), and vPI using an in vitro flow phantom model. We separated gains into 3 bands -8 to -1 (no noise), -1 to +5 (low noise), and +5 to +8 (obvious noise). The vPI was determined from the 3-dimensional VI or VFI using the formula vPI = (maximum - minimum)/mean. Using no-noise gains, we observed that although the VI and VFI increased linearly with gain, the vPI was substantially less dependent on this adjustment. The VI and VFI continued to increase linearly with gain, whereas the vPI decreased slightly using low-noise gains. When gain was increased above the lower limit of obvious noise (+5), the VI and VFI increased noticeably, and there were marked reductions in both vPI values. We conclude that the vPI is less affected by changes in color gain than the VI and VFI at no-noise gains.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vasos Sanguíneos
/
Algoritmos
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Fluxo Pulsátil
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Interpretação de Imagem Assistida por Computador
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Ultrassonografia Doppler
/
Imageamento Tridimensional
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Ultrasound Med
Ano de publicação:
2013
Tipo de documento:
Article