Detection of Doppler embolic signals: psychoacoustic considerations.
Ultrasound Med Biol
; 31(9): 1177-84, 2005 Sep.
Article
en En
| MEDLINE
| ID: mdl-16176785
ABSTRACT
The purpose of this study was to improve reliability in the identification of Doppler embolic signals by determining the decibel threshold for reproducible detection of simulated "emboli" as a function of signal duration, frequency and cardiac-cycle position. The auditory sensitivity of 16 participants to 574 simulated "emboli" was examined using psychoacoustic techniques to assess how the probability of detection varies with embolic signal parameters. Detailed measurements of the threshold for detection of simulated embolic signals are presented. These provide evidence that the measured embolus-to-blood threshold ranges between 2 dB and 14 dB as a continuous function of signal duration and frequency. The level of the threshold is closely linked to both embolic signal parameters and the properties of the blood flow signal. We conclude that the current fixed choice of threshold does not provide a good approximation to the true threshold of detection across the full range of embolic signal parameters.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Psicoacústica
/
Embolia y Trombosis Intracraneal
/
Ultrasonografía Doppler Transcraneal
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Ultrasound Med Biol
Año:
2005
Tipo del documento:
Article
País de afiliación:
Reino Unido