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Attenuation Coefficient Estimation of Normal Placentas.

Farah Deeba1, Manyou Ma1, Mehran Pesteie1

  • 1Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, British Columbia, Canada.

Ultrasound in Medicine & Biology
|January 28, 2019
PubMed
Summary
This summary is machine-generated.

This study introduces a new method for selecting regions in ultrasound images to estimate the attenuation coefficient in placental tissue. This technique improves accuracy and reduces variability, enhancing its clinical use.

Keywords:
Attenuation coefficient estimateEnvelope signal-to-noise ratioPlacentaPulse bandwidthReference phantom method

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Area of Science:

  • Biomedical Ultrasound
  • Medical Imaging
  • Tissue Characterization

Background:

  • Attenuation coefficient estimation (ACE) shows promise for placental tissue characterization.
  • Biological tissue inhomogeneities cause significant variance in ACE, limiting clinical applications.

Purpose of the Study:

  • To develop and validate a novel Attenuation Estimation Region Of Interest (AEROI) selection method.
  • To improve the accuracy and reduce the variability of ACE in placental tissue.

Main Methods:

  • The proposed AEROI method utilizes envelope signal-to-noise ratio deviation and transmit pulse bandwidth's coefficient of variation.
  • Validation was performed on a tissue-mimicking phantom and subsequently on 59 post-delivery placentas.

Main Results:

  • Phantom validation showed an 18%-21% reduction in ACE standard deviation and a 14%-24% reduction in ACE error.
  • In placental studies, the AEROI method decreased intra-subject ACE standard deviation from 0.72 to 0.39 dB/cm/MHz.
  • A baseline ACE of 0.77 ± 0.37 dB/cm/MHz was established for normal placentas.

Conclusions:

  • The novel AEROI selection method effectively reduces ACE variability and error in placental tissue.
  • This improved method enhances the clinical utility of attenuation coefficient estimation for placental characterization.