Method for determining the SATA and SAPA intensities for real-time ultrasonographic scanning modes

Macdonald, M C; Madsen, Ernest L.

doi:10.7863/jum.1992.11.1.11

Cited by 3 publications

(2 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…21 Definitions and tabulated values for spatial peak temporal peak (SPTP), spatial average temporal average (SAT A), and spatial average pulse average (SAPA) intensities also are given in that paper. 21 Data for computing exposure intensities were gathered using a calibrated needle-type hydrophone with a 0.6 mm diameter PVDF receiving element coupled to a LeCroy 9400 digital oscilloscope, Chestnut Ridge, NY, and a Compaq 386 computer, Houston, TX. During measurement, the agar disc, gimbal mount, and supporting structure shown in Figure B were removed.…”

Section: Monitoring Of Ultrasound Exposuresmentioning

confidence: 99%

Method of cavitation-suppressed exposure of cells and explant mouse embryos to clinical real-time and pulsed Doppler ultrasound.

Madsen

Frank²,

Macdonald³

et al. 1991

Journal of Ultrasound in Medicine

Self Cite

View full text Add to dashboard Cite

An apparatus and procedure for well-controlled exposure of cells or explant mouse embryos to clinical real-time ultrasound are described. Cells or embryos to be exposed are suspended in media made sufficiently viscous through inclusion of methylcellulose that cavitation is suppressed but thermal effects remain negligible. During exposure, the scanning beam is precisely centered in a 2 mm x 20 mm slot in a 20 cm diameter agar disc containing the suspension. The high viscosity causes the cells to remain distributed uniformly throughout the exposure; this fact, along with precision beam alignment, ensures that exposure is well defined. Exposure data are acquired with a 0.6 mm diameter hydrophone.

show abstract

Section: Monitoring Of Ultrasound Exposuresmentioning

confidence: 99%

Method of cavitation-suppressed exposure of cells and explant mouse embryos to clinical real-time and pulsed Doppler ultrasound.

Madsen

Frank²,

Macdonald³

et al. 1991

Journal of Ultrasound in Medicine

Self Cite

View full text Add to dashboard Cite

show abstract

“…The method of data acquisition and reduction employed to determine these SAT A and SAP A values are described elsewhere. 15 Specification of exposure also involves the duration of time over which the cells or embryos were in a position to be affected by the ultrasonic beam. This is taken to be a continuous period of time as measured by a stopwatch.…”

Section: Exposure Monitoringmentioning

confidence: 99%

The role of preimplantation sonographic exposure in postimplantation development and pregnancy outcome.

Iannaccone

Gorder²,

Madsen³

et al. 1991

Journal of Ultrasound in Medicine

Self Cite

View full text Add to dashboard Cite

To determine what, if any, effects exposure to ultrasonic beams has on preimplantation embryos we iso· lated mouse blastocysts and assessed resorption rate, pregnancy rate, decidual swelling volume, and live birth rate after in vitro exposure with subsequent transfer to surrogate mothers. The blastocyst stage embryos were isolated by flushing the uteri of pregnant animals with a phosphate buffered medium. Blastocysts at a discrete stage of development were pooled and transferred to a PBl ·methykellulose medium. This medium is specifically designed to maintain the embryos in a high viscosity solution during the sonographic expo· sure to prevent microcavitation. After the exposure, the embryos were washed free of methylcellulose and T he commonly held notion that the preimplantation embryo is safe from the noxious effects of chemical disruption has been shown to be an oversimplification. u The blastocyst stage of the preimplantation embryogenesis is a period of critical genetic determination and differentiation? It is incorrect to assume that this period is not susceptible to subtle nonlethal mutations that may result in poor pregnancy outcome, including dysmorphogenesis.4-B Recently our group and others have confirmed that transferred to the uteri of pseudopregnant surrogate mothers. A total of 660 blastocyst stage embryos were distributed among seven treatment groups. After exposure, the embryos were transferred to 54 surrogate mothers. A total of 199 embryos were implanted successfully for postimplantation evaluation. An additional 427 blastocysts were distributed among four treatment groups and transferred to 46 surrogate moth· ers to assess the effect of sonographic exposure on birth rate. The results indicate possible deleterious effects (decreased implantation rate, increased resorption rate, decreased decidual swelling volume, and increased stillbirth rate) of short ultrasonic exposures (1 min and 5 min) on mouse blastocyst function.exposure to methylnitrosourea (MNU), a direct-acting mutagen, can result in significant postimplantation dysmorphogenesis after exposure in the preimplantation stage-that is, during middle to late gestation but Jong after the exposure.

show abstract

Intrauterine effects of ultrasound: Animal studies

Jensh

Brent

1999

Teratology

View full text Add to dashboard Cite

During the past several decades, the use of ultrasound technology in the clinical setting has greatly increased. Because nearly every pregnant woman receives at least one sonographic procedure today, there has been developing concern about the safety of such procedures. Since ultrasound exposure can result in hyperthermia and other physiological effects, the determination of a threshold or no‐effect exposure has become a high‐priority goal. Animal research has been important to the study of the effects of various exposures at all stages of pregnancy, since the clinical use of ultrasonography can occur during the preimplantation, organogenic, and fetal stages. Animal experiments using various mammalian species have been able to determine no‐effect exposure levels for embryonic loss, congenital malformations and neurobehavioral effects. The preponderance of evidence from these studies indicates that, in the absence of a thermal effect, ultrasonography represents no measurable risk when used at recommended intensity levels. Teratology 59:240–251, 1999. © 1999 Wiley‐Liss, Inc.

show abstract

Method for determining the SATA and SAPA intensities for real-time ultrasonographic scanning modes

Cited by 3 publications

References 5 publications

Method of cavitation-suppressed exposure of cells and explant mouse embryos to clinical real-time and pulsed Doppler ultrasound.

Method of cavitation-suppressed exposure of cells and explant mouse embryos to clinical real-time and pulsed Doppler ultrasound.

The role of preimplantation sonographic exposure in postimplantation development and pregnancy outcome.

Intrauterine effects of ultrasound: Animal studies

Contact Info

Product

Resources

About