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A 31-channel MR brain array coil compatible with positron emission tomography.

ABSTRACT: Simultaneous acquisition of MR and positron emission tomography (PET) images requires the placement of the MR detection coil inside the PET detector ring where it absorbs and scatters photons. This constraint is the principal barrier to achieving optimum sensitivity on each modality. Here, we present a 31-channel PET-compatible brain array coil with reduced attenuation but improved MR sensitivity.A series of component tests were performed to identify tradeoffs between PET and MR performance. Aspects studied include the remote positioning of preamplifiers, coax size, coil trace size/material, and plastic housing. We then maximized PET performance at minimal cost to MR sensitivity. The coil was evaluated for MR performance (signal to noise ratio [SNR], g-factor) and PET attenuation.The coil design showed an improvement in attenuation by 190% (average) compared with conventional 32-channel arrays, and no loss in MR SNR. Moreover, the 31-channel coil displayed an SNR improvement of 230% (cortical region of interest) compared with a PET-optimized 8-channel array with similar attenuation properties. Implementing attenuation correction of the 31-channel array successfully removed PET artifacts, which were comparable to those of the 8-channel array.The design of the 31-channel PET-compatible coil enables higher sensitivity for PET/MR imaging, paving the way for novel applications in this hybrid-imaging domain.

SUBMITTER: Sander CY

PROVIDER: S-EPMC4500638 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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A 31-channel MR brain array coil compatible with positron emission tomography.

Sander Christin Y CY Keil Boris B Chonde Daniel B DB Rosen Bruce R BR Catana Ciprian C Wald Lawrence L LL

Magnetic resonance in medicine 20140707 6

<h4>Purpose</h4>Simultaneous acquisition of MR and positron emission tomography (PET) images requires the placement of the MR detection coil inside the PET detector ring where it absorbs and scatters photons. This constraint is the principal barrier to achieving optimum sensitivity on each modality. Here, we present a 31-channel PET-compatible brain array coil with reduced attenuation but improved MR sensitivity.<h4>Methods</h4>A series of component tests were performed to identify tradeoffs bet ...[more]

PMID: 25046699

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Dataset Information

A 31-channel MR brain array coil compatible with positron emission tomography.

Publications

A 31-channel MR brain array coil compatible with positron emission tomography.

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