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Audio spectrum analysis of umbilical artery Doppler ultrasound signals

Thuring, Ann LU (2015) In Lund University, Faculty of Medicine Doctoral Dissertation Series 2015:10.
Abstract
The aim of this thesis was to develop an objective method for evaluation of umbilical artery

circulation based on auditory perception of the Doppler sound signals.

Study I. The operator listened to synthetically produced sound signals from continuous flow. The

human ear was most sensitive to sound frequencies in the lower range from this type of flow.

Study II. Doppler signals were recorded from the umbilical artery of sheep fetuses. An objective

sound measure, MAXpeak-15dB (the frequency band where the energy level had decreased by 15

dB from its maximum level) was identified and found to correlate well with the sonographer’s

subjective grading and with the traditional... (More)
The aim of this thesis was to develop an objective method for evaluation of umbilical artery

circulation based on auditory perception of the Doppler sound signals.

Study I. The operator listened to synthetically produced sound signals from continuous flow. The

human ear was most sensitive to sound frequencies in the lower range from this type of flow.

Study II. Doppler signals were recorded from the umbilical artery of sheep fetuses. An objective

sound measure, MAXpeak-15dB (the frequency band where the energy level had decreased by 15

dB from its maximum level) was identified and found to correlate well with the sonographer’s

subjective grading and with the traditional waveform analysis.

Studies III and IV. Fetoplacental and uteroplacental circulation was investigated before and

after treatment with corticosteroids of women at risk for preterm birth. A transient decrease in

pulsatility index (PI) in the umbilical artery and ductus venosus occurred after steroid treatment.

MAXpeak-15dB increased significantly after corticosteroids parallel with a decrease in PI and was

more sensitive to the changes in flow.

Study V. MAXpeak-15dB was applied on umbilical artery Doppler signals in high-risk pregnancies

and was found to show similar results as the traditional PI in predicting the probability of

composite adverse pregnancy outcome. Receiver operating characteristic curves were used with

an area under curve (AUC) of 0.842 for MAXpeak-15dB and 0.836 for PI. When the two parameters

were combined the predictive performance was improved (AUC 0.894). MAXpeak-15dB might thus

provide additional clinically useful information on the hemodynamics of fetoplacental circulation. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Axelsson, Ove, Uppsala University
organization
publishing date
type
Thesis
publication status
published
subject
in
Lund University, Faculty of Medicine Doctoral Dissertation Series
volume
2015:10
pages
47 pages
publisher
Department of Clinical Sciences, Lund University
defense location
Department of Obstetrics and Gynecology, plan 3, Skånes Universitetssjukhus, Lund
defense date
2015-01-23 09:15
ISSN
1652-8220
ISBN
978-91-7619-090-6
language
English
LU publication?
yes
id
9a470501-99ed-417b-bce1-609787363bd9 (old id 4905135)
date added to LUP
2015-01-07 10:25:39
date last changed
2016-09-19 08:44:46
@phdthesis{9a470501-99ed-417b-bce1-609787363bd9,
  abstract     = {The aim of this thesis was to develop an objective method for evaluation of umbilical artery<br/><br>
circulation based on auditory perception of the Doppler sound signals.<br/><br>
Study I. The operator listened to synthetically produced sound signals from continuous flow. The<br/><br>
human ear was most sensitive to sound frequencies in the lower range from this type of flow.<br/><br>
Study II. Doppler signals were recorded from the umbilical artery of sheep fetuses. An objective<br/><br>
sound measure, MAXpeak-15dB (the frequency band where the energy level had decreased by 15<br/><br>
dB from its maximum level) was identified and found to correlate well with the sonographer’s<br/><br>
subjective grading and with the traditional waveform analysis.<br/><br>
Studies III and IV. Fetoplacental and uteroplacental circulation was investigated before and<br/><br>
after treatment with corticosteroids of women at risk for preterm birth. A transient decrease in<br/><br>
pulsatility index (PI) in the umbilical artery and ductus venosus occurred after steroid treatment.<br/><br>
MAXpeak-15dB increased significantly after corticosteroids parallel with a decrease in PI and was<br/><br>
more sensitive to the changes in flow.<br/><br>
Study V. MAXpeak-15dB was applied on umbilical artery Doppler signals in high-risk pregnancies<br/><br>
and was found to show similar results as the traditional PI in predicting the probability of<br/><br>
composite adverse pregnancy outcome. Receiver operating characteristic curves were used with<br/><br>
an area under curve (AUC) of 0.842 for MAXpeak-15dB and 0.836 for PI. When the two parameters<br/><br>
were combined the predictive performance was improved (AUC 0.894). MAXpeak-15dB might thus<br/><br>
provide additional clinically useful information on the hemodynamics of fetoplacental circulation.},
  author       = {Thuring, Ann},
  isbn         = {978-91-7619-090-6},
  issn         = {1652-8220},
  language     = {eng},
  pages        = {47},
  publisher    = {Department of Clinical Sciences, Lund University},
  school       = {Lund University},
  series       = {Lund University, Faculty of Medicine Doctoral Dissertation Series},
  title        = {Audio spectrum analysis of umbilical artery Doppler ultrasound signals},
  volume       = {2015:10},
  year         = {2015},
}