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High temporal resolution dynamic MRI and arterial input function for assessment of GFR in pediatric subjects.

ABSTRACT: To introduce a respiratory-gated high-spatiotemporal-resolution dynamic-contrast-enhanced MRI technique and a high-temporal-resolution aortic input function (HTR-AIF) estimation method for glomerular filtration rate (GFR) assessment in children.A high-spatiotemporal-resolution DCE-MRI method with view-shared reconstruction was modified to incorporate respiratory gating, and an AIF estimation method that uses a fraction of the k-space data from each respiratory period was developed (HTR-AIF). The method was validated using realistic digital phantom simulations and demonstrated on clinical subjects. The GFR estimates using HTR-AIF were compared with estimates obtained by using an AIF derived directly from the view-shared images.Digital phantom simulations showed that using the HTR-AIF technique gives more accurate AIF estimates (RMSE = 0.0932) compared with the existing estimation method (RMSE = 0.2059) that used view-sharing (VS). For simulated GFR > 27 mL/min, GFR estimation error was between 32% and 17% using view-shared AIF, whereas estimation error was less than 10% using HTR-AIF. In all clinical subjects, the HTR-AIF method resulted in higher GFR estimations than the view-shared method.The HTR-AIF method improves the accuracy of both the AIF and GFR estimates derived from the respiratory-gated acquisitions, and makes GFR estimation feasible in free-breathing pediatric subjects.

SUBMITTER: Yoruk U

PROVIDER: S-EPMC4636486 | biostudies-other | 2016 Mar

REPOSITORIES: biostudies-other

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High temporal resolution dynamic MRI and arterial input function for assessment of GFR in pediatric subjects.

Yoruk Umit U Saranathan Manojkumar M Loening Andreas M AM Hargreaves Brian A BA Vasanawala Shreyas S SS

Magnetic resonance in medicine 20150506 3

<h4>Purpose</h4>To introduce a respiratory-gated high-spatiotemporal-resolution dynamic-contrast-enhanced MRI technique and a high-temporal-resolution aortic input function (HTR-AIF) estimation method for glomerular filtration rate (GFR) assessment in children.<h4>Methods</h4>A high-spatiotemporal-resolution DCE-MRI method with view-shared reconstruction was modified to incorporate respiratory gating, and an AIF estimation method that uses a fraction of the k-space data from each respiratory per ...[more]

PMID: 25946307

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High temporal resolution dynamic MRI and arterial input function for assessment of GFR in pediatric subjects.

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High temporal resolution dynamic MRI and arterial input function for assessment of GFR in pediatric subjects.

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