Chinese Journal of Magnetic Resonance >
Improving Signal-to-Noise Ratio in Magnetic Resonance Imaging Using Dynamic Receiver Gain
Received date: 2014-04-16
Revised date: 2014-11-04
Online published: 2014-12-05
Supported by
国家科技重大专项资助项目(2011ZX05008-004).
A method to increase signal-to-noise ratio (SNR) in magnetic resonance imaging using dynamic receiver gain was proposed. In the method, the receiver gain was adjusted dynamically according to amplitude of each echo signal before acquisition. By doing so, the receiver dynamic range could be optimized to improve SNR of each acquisition. To reconstruct the images, a double-precision floating-point arithmetic processing procedure was used to expand the dynamic range of all acquisitions to the same scale. Imaging experiments were conducted using the proposed method on a 1.5 T clinical MRI scanner.
The results showed that the SNR of T1-weighted images could be improved by approximately 10%, compared to the fixed-receiver-gain images. More importantly, the method proposed needs no extra circuits or multiple time-consuming scans. It is concluded that using dynamic receiver gain for each acquisition is an effective way to improve SNR in MR imaging, especially for high-resolution and high-filed imaging applications.
Key words： MRI; dynamic receiver gain; quantization noise; dynamic range; signal-tonoise ratio
SUN Hong-yu1 , TANG Wei-nan2 , WANG Wei-min1* . Improving Signal-to-Noise Ratio in Magnetic Resonance Imaging Using Dynamic Receiver Gain[J]. Chinese Journal of Magnetic Resonance, 2014 , 31(4) : 515 -522 . DOI: 10.11938/cjmr20140406
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