title: Examination of a low-cost pocket Doppler device for fetal assessment.
abstract: The objective of this study was to evaluate a pocket Doppler device (Multi Dopplex II) for the waveform analysis of umbilical artery systolic/diastolic (S/D) ratios and resistance index (RI). A prospective, paired study was undertaken in a perinatal ultrasound unit in a tertiary referral hospital. Forty-three high-risk pregnant women beyond 16 weeks' gestation had fetal umbilical artery flow velocity waveforms recorded with both Multi Dopplex II and duplex Doppler devices and the waveform analyses were calculated. The Multi Dopplex II falsely indicated absent diastolic flow in two cases and failed to produce a flow velocity waveform in the presence of maternal obesity, polyhydramnios and some cases of anterior placenta (n = 8). As well as this, the limits of agreement overall for both S/D ratio and RI were wide (for S/D ratio, -1.6 to 2.2 and for RI, -0.20 to 0.20). Even though the levels of agreement were better for the third trimester (for S/D ratio, -0.8 to 1.1 and for RI, -0.10 to 0.20), we concluded that the limits of agreement were too wide for clinical use.
authors.affiliation: St. Bartholomew's Hospital, London, UK.
authors.forename: M
authors.initials: M
authors.lastname: Lockett
authors.forename: A
authors.initials: A
authors.lastname: Bisits
authors.forename: W B
authors.initials: WB
authors.lastname: Giles
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D016001:Confidence Intervals; D005069:Evaluation Studies as Topic; D005260:Female; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D018617:Ultrasonography, Doppler, Pulsed / Q000295:instrumentation*; D016216:Ultrasonography, Prenatal / Q000295:instrumentation*; D014469:Umbilical Arteries / Q000000981:diagnostic imaging*