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:PurposeContrast-enhanced ultrasound imaging has expanded the diagnostic potential of ultrasound by enabling real-time imaging and quantification of tissue perfusion. Several perfusion models and curve fitting methods have been developed to quantify the temporal behavior of tracer signal and standardize perfusion quantification. While the least-squares approach has traditionally been applied for curve fitting, it can be inadequate for noisy and complex data. Moreover, previous research suggests that certain perfusion models may be more relevant depending on the organ or tissue imaged. We propose a multi-model framework to select the most appropriate perfusion model and curve fitting method for each diagnostic application.MethodsOur multi-model approach uses a system identification method, which estimates perfusion parameters from the model with the best fit to a given time-intensity curve. We compared current perfusion quantification methods that use a single perfusion model and curve fitting method and our proposed multi-model framework on bolus 3D dynamic contrast-enhanced ultrasound (DCE-US) in vivo images obtained in mice implanted with a colon cancer, as well as on simulation data. The quality of fit in estimating perfusion parameters was evaluated using the Spearman correlation coefficient, the coefficient of determination (R2 ), and the normalized root-mean-square error (NRMSE) to ensure that the multi-model framework finds the best perfusion model and curve fitting algorithm.ResultsOur multi-model framework outperforms conventional single perfusion model approaches with least-squares optimization, providing more robust perfusion parameter estimation. R2 and NRMSE are 0.98 and 0.18, respectively, for our proposed method. By comparison, the performance of the traditional approach is much more dependent upon the selection of the appropriate model. The R2 and NRMSE are 0.91 and 0.31, respectively.ConclusionsThe proposed multi-model framework for perfusion modeling outperforms the current approach of single perfusion modeling using least-squares optimization and more robustly estimates perfusion parameters when using empiric data labeled by an expert as the gold standard. Our technique is minimally sensitive to issues affecting the accuracy of perfusion parameter estimation, including rise time, noise, region of interest size, and frame rate. This framework could be of key utility in modeling different perfusion systems in different tissues and organs.

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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.

Similar Datasets

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