Work

Practical signal‐to‐noise ratio quantification for sensitivity encoding: Application to coronary MR angiography

Year: 2011

Type: article

Abstract: PURPOSE: To develop and evaluate a practical method for the quantification of signal-to-noise ratio (SNR) on coronary MR angiograms (MRA) acquired with parallel imaging. MATERIALS AND METHODS: To quantify the spatially varying noise due to parallel imaging reconstruction, a new method has been implemented incorporating image data acquisition followed by a fast noise scan during which radiofrequency pulses, cardiac triggering and navigator gating are disabled. The performance of this method was evaluated in a phantom study where SNR measurements were compared with those of a reference standard (multiple repetitions). Subsequently, SNR of myocardium and posterior skeletal muscle was determined on in vivo human coronary MRA. RESULTS: In a phantom, the SNR measured using the proposed method deviated less than 10.1% from the reference method for small geometry factors (≤2). In vivo, the noise scan for a 10 min coronary MRA acquisition was acquired in 30 s. Higher signal and lower SNR, due to spatially varying noise, were found in myocardium compared with posterior skeletal muscle. CONCLUSION: SNR quantification based on a fast noise scan is a validated and easy-to-use method when applied to three-dimensional coronary MRA obtained with parallel imaging as long as the geometry factor remains low.

Source: Journal of Magnetic Resonance Imaging

DOI: 10.1002/jmri.22571

Authors: Jing Yu, Harsh Agarwal, Matthias Stuber, Michael Schär

Institutions: Johns Hopkins University, Centre Hospitalier Universitaire Vaudois, Centre d'Imagerie BioMedicale, University of Lausanne

Language: English

Topic: Advanced MRI Techniques and Applications

Subfield: Radiology, Nuclear Medicine and Imaging

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: bronze

Funders: Johns Hopkins University, National Institutes of Health, National Heart, Lung, and Blood Institute