Dataset Information

Simultaneous ¹³N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

ABSTRACT:

Background

Positron emission tomography (PET) is the non-invasive reference standard for myocardial blood flow (MBF) quantification. Hybrid PET-MR allows simultaneous PET and cardiac magnetic resonance (CMR) acquisition under identical experimental and physiological conditions. This study aimed to determine feasibility of simultaneous ¹³N-Ammonia PET and dynamic contrast-enhanced CMR MBF quantification in phantoms and healthy volunteers.

Methods

Images were acquired using a 3T hybrid PET-MR scanner. Phantom study: MBF was simulated at different physiological perfusion rates and a protocol for simultaneous PET-MR perfusion imaging was developed. Volunteer study: five healthy volunteers underwent adenosine stress. ¹³N-Ammonia and gadolinium were administered simultaneously. PET list mode data was reconstructed using ordered subset expectation maximisation. CMR MBF was quantified using Fermi function-constrained deconvolution of arterial input function and myocardial signal. PET MBF was obtained using a one-tissue compartment model and image-derived input function.

Results

Phantom study: PET and CMR MBF measurements demonstrated high repeatability with intraclass coefficients 0.98 and 0.99, respectively. There was high correlation between PET and CMR MBF (r = 0.98, p < 0.001) and good agreement (bias - 0.85 mL/g/min; 95% limits of agreement 0.29 to - 1.98). Volunteer study: Mean global stress MBF for CMR and PET were 2.58 ± 0.11 and 2.60 ± 0.47 mL/g/min respectively. On a per territory basis, there was moderate correlation (r = 0.63, p = 0.03) and agreement (bias - 0.34 mL/g/min; 95% limits of agreement 0.49 to - 1.18).

Conclusion

Simultaneous MBF quantification using hybrid PET-MR imaging is feasible with high test repeatability and good to moderate agreement between PET and CMR. Future studies in coronary artery disease patients may allow cross-validation of techniques.

SUBMITTER: Nazir MS

PROVIDER: S-EPMC6718374 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Simultaneous <sup>13</sup>N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

Nazir Muhummad Sohaib MS Gould Sarah-May SM Milidonis Xenios X Reyes Eliana E Ismail Tevfik F TF Neji Radhouene R Roujol Sébastien S O'Doherty Jim J Xue Hui H Barrington Sally F SF Schaeffter Tobias T Razavi Reza R Marsden Paul P Kellman Peter P Plein Sven S Chiribiri Amedeo A

European journal of hybrid imaging 20190903 1

<h4>Background</h4>Positron emission tomography (PET) is the non-invasive reference standard for myocardial blood flow (MBF) quantification. Hybrid PET-MR allows simultaneous PET and cardiac magnetic resonance (CMR) acquisition under identical experimental and physiological conditions. This study aimed to determine feasibility of simultaneous <sup>13</sup>N-Ammonia PET and dynamic contrast-enhanced CMR MBF quantification in phantoms and healthy volunteers.<h4>Methods</h4>Images were acquired usi ...[more]

PMID: 31544170

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Dataset Information

Simultaneous ¹³N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

Background

Methods

Results

Conclusion

Publications

Simultaneous <sup>13</sup>N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

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Dataset Information

Simultaneous 13N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

Background

Methods

Results

Conclusion

Publications

Simultaneous &lt;sup&gt;13&lt;/sup&gt;N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Simultaneous ¹³N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.

Simultaneous <sup>13</sup>N-Ammonia and gadolinium first-pass myocardial perfusion with quantitative hybrid PET-MR imaging: a phantom and clinical feasibility study.