Reducing PNS with minimal performance penalties via simple pulse sequence modifications on a high-performance compact 3T scanner.

Reducing PNS with minimal performance penalties via simple pulse sequence modifications on a high-performance compact 3T scanner. Phys Med Biol. 2020 Jun 05;: Authors: In MH, Shu Y, Trzasko JD, Yarach U, Kang D, Gray EM, Huston Iii J, Bernstein MA Abstract One of the major concerns associated with high-performance gradients is peripheral nerve stimulation (PNS) of the subject during MRI exams. Since the installation, more than 680 volunteer subjects (patients and controls) have been scanned on a compact 3T MRI system with high-performance gradients, capable of 80 mT/m gradient amplitude and 700 T/m/s slew rate simultaneously. Despite PNS concerns associated with the high-performance gradients, due to the smaller physical dimensions of the gradient coils, minimal or no PNS sensation was reported with most pulse sequences. The exception was PNS reported by only five of 252 subjects (about 2%) scanned with a specific 3D fast spin echo pulse sequence (3DFLAIR). Rather than derating the entire system performance across all pulse sequences and all gradient lobes, we addressed reported PNS effect with a simple and specific modification to the targeted lobes of the problematic pulse sequence. In addition, the PNS convolutional model was adapted to predict sequence-specific PNS threshold level and its reduction after derating. The effectiveness of the targeted pulse sequence modification was demonstrated by successfully re-scanning four of th...
Source: Physics in Medicine and Biology - Category: Physics Authors: Tags: Phys Med Biol Source Type: research
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