Dataset Information

Ultrafast Ultrasound Imaging for Super-Resolution Preclinical Cardiac PET.

ABSTRACT:

Purpose

Physiological motion and partial volume effect (PVE) significantly degrade the quality of cardiac positron emission tomography (PET) images in the fast-beating hearts of rodents. Several Super-resolution (SR) techniques using a priori anatomical information have been proposed to correct motion and PVE in PET images. Ultrasound is ideally suited to capture real-time high-resolution cine images of rodent hearts. Here, we evaluated an ultrasound-based SR method using simultaneously acquired and co-registered PET-CT-Ultrafast Ultrasound Imaging (UUI) of the beating heart in closed-chest rodents.

Procedures

The method was tested with numerical and animal data (n?=?2) acquired with the non-invasive hybrid imaging system PETRUS that acquires simultaneously PET, CT, and UUI.

Results

We showed that ultrasound-based SR drastically enhances the quality of PET images of the beating rodent heart. For the simulations, the deviations between expected and mean reconstructed values were 2 % after applying SR. For the experimental data, when using Ultrasound-based SR correction, contrast was improved by a factor of two, signal-to-noise ratio by 11 %, and spatial resolution by 56 % (~?0.88 mm) with respect to static PET. As a consequence, the metabolic defect following an acute cardiac ischemia was delineated with much higher anatomical precision.

Conclusions

Our results provided a proof-of-concept that image quality of cardiac PET in fast-beating rodent hearts can be significantly improved by ultrasound-based SR, a portable low-cost technique. Improved PET imaging of the rodent heart may allow new explorations of physiological and pathological situations related with cardiac metabolism.

SUBMITTER: Perez-Liva M

PROVIDER: S-EPMC7497458 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Ultrafast Ultrasound Imaging for Super-Resolution Preclinical Cardiac PET.

Perez-Liva Mailyn M Yoganathan Thulaciga T Herraiz Joaquin L JL Porée Jonathan J Tanter Mickael M Balvay Daniel D Viel Thomas T Garofalakis Anikitos A Provost Jean J Tavitian Bertrand B

Molecular imaging and biology 20200629 5

<h4>Purpose</h4>Physiological motion and partial volume effect (PVE) significantly degrade the quality of cardiac positron emission tomography (PET) images in the fast-beating hearts of rodents. Several Super-resolution (SR) techniques using a priori anatomical information have been proposed to correct motion and PVE in PET images. Ultrasound is ideally suited to capture real-time high-resolution cine images of rodent hearts. Here, we evaluated an ultrasound-based SR method using simultaneously ...[more]

PMID: 32602084

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Dataset Information

Ultrafast Ultrasound Imaging for Super-Resolution Preclinical Cardiac PET.

Purpose

Procedures

Results

Conclusions

Publications

Ultrafast Ultrasound Imaging for Super-Resolution Preclinical Cardiac PET.

Similar Datasets

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