Dataset Information

Contrast-enhanced ultrasound reveals real-time spatial changes in vascular perfusion during early implantation in the macaque uterus.

ABSTRACT:

Objective

To use contrast-enhanced ultrasound (CEU) to quantify blood flow in the macaque uterus during early pregnancy.

Design

Prospective nonhuman primate study.

Setting

Oregon National Primate Research Center.

Animals

Naturally cycling female rhesus macaques (Macaca mulatta).

Intervention(s)

Female macaques were mated on days 11-14 of the cycle. Females were then imaged by CEU and Doppler ultrasound once every 3 days from day 21 through day 39 of the fertile cycle.

Main outcome measure(s)

Visualization and quantification of uterine vascular perfusion.

Result(s)

CEU identified the primary placental disc and underlying vessels approximately 2 days earlier than Doppler ultrasound was able to observe endometrial thickening. CEU revealed spatial differences in vascular perfusion between the endometrium, myometrium, and endometrial-myometrial (junctional) zone. Myometrium displayed the highest rate of blood flow (>10 mL/min/g tissue). There was less blood flow in the endometrium and junctional zone (<3 mL/min/g). A brief fall in progesterone was observed during early implantation, which was correlated with reduced blood flow to all three uterine compartments, but did not reduce flow to the placenta.

Conclusions

CEU provides a sensitive, noninvasive method to assess vascular perfusion of the uterus during embryo implantation in macaques. We propose CEU as a new diagnostic tool to monitor vascular changes associated with early pregnancy in women.

SUBMITTER: Keator CS

PROVIDER: S-EPMC3070443 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Publications

Contrast-enhanced ultrasound reveals real-time spatial changes in vascular perfusion during early implantation in the macaque uterus.

Keator Christopher S CS Lindner Jonathan R JR Belcik J Todd JT Bishop Cecily V CV Slayden Ov D OD

Fertility and sterility 20110301 4

<h4>Objective</h4>To use contrast-enhanced ultrasound (CEU) to quantify blood flow in the macaque uterus during early pregnancy.<h4>Design</h4>Prospective nonhuman primate study.<h4>Setting</h4>Oregon National Primate Research Center.<h4>Animals</h4>Naturally cycling female rhesus macaques (Macaca mulatta).<h4>Intervention(s)</h4>Female macaques were mated on days 11-14 of the cycle. Females were then imaged by CEU and Doppler ultrasound once every 3 days from day 21 through day 39 of the fertil ...[more]

PMID: 21316046

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Project description:BackgroundThere is growing interest in limb contrast-enhanced ultrasound (CEU) perfusion imaging for the evaluation of peripheral artery disease. Because of low resting microvascular blood flow in skeletal muscle, signal enhancement during limb CEU is prohibitively low for real-time imaging. The aim of this study was to test the hypothesis that this obstacle can be overcome by intermediate- rather than low-power CEU when performed with an acoustically resilient microbubble agent.MethodsViscoelastic properties of Definity and Sonazoid were assessed by measuring bulk modulus during incremental increases in ambient pressure to 200 mm Hg. Comparison of in vivo microbubble destruction and signal enhancement at a mechanical index (MI) of 0.1 to 0.4 was performed by sequential reduction in pulsing interval from 10 to 0.05 sec during limb CEU at 7 MHz in mice and 1.8 MHz in dogs. Destruction was also assessed by broadband signal generation during passive cavitation detection. Real-time CEU perfusion imaging with destruction-replenishment was then performed at 1.8 MHz in dogs using an MI of 0.1, 0.2, or 0.3.ResultsSonazoid had a higher bulk modulus than Definity (66 ± 12 vs 29 ± 2 kPa, P = .02) and exhibited less inertial cavitation (destruction) at MIs ≥ 0.2. On in vivo CEU, maximal signal intensity increased incrementally with MI for both agents and was equivalent between agents except at an MI of 0.1 (60% and 85% lower for Sonazoid at 7 and 1.8 MHz, respectively, P < .05). However, on progressive shortening of the pulsing interval, Definity was nearly completely destroyed at MIs ≥ 0.2 at 1.8 and 7 MHz, whereas Sonazoid was destroyed only at 1.8 MHz at MIs ≥ 0.3. As a result, real-time CEU perfusion imaging demonstrated approximately fourfold greater enhancement for Sonazoid at an MI of 0.3 to 0.4.ConclusionsRobust signal enhancement during real-time CEU perfusion imaging of the limb is possible when using intermediate-power imaging coupled with a durable microbubble contrast agent.

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Dataset Information

Contrast-enhanced ultrasound reveals real-time spatial changes in vascular perfusion during early implantation in the macaque uterus.

Objective

Design

Setting

Animals

Intervention(s)

Main outcome measure(s)

Result(s)

Conclusions

Publications

Contrast-enhanced ultrasound reveals real-time spatial changes in vascular perfusion during early implantation in the macaque uterus.

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