Assessment of velopharyngeal function with dual-planar high-resolution real-time spiral dynamic MRI

Abstract

Purpose: To develop a real-time dynamic MRI method for comprehensive evaluation of velum movement during speech.

Methods: Dynamic MRI has been used to study velopharyngeal insufficiency (VPI) by imaging the movement of the velum during speech, because it can provide good anatomic details with no exposed radiation. To be able to comprehensively evaluate dynamic velum movement, a real-time spiral non-balanced SSFP sequence was developed with simultaneous dual-planar coverage and improved spatial and temporal resolution using a combination of parallel imaging and spatial and temporal compressed sensing to achieve 6 × acceleration. New off-resonance correction and post-processing methods were also developed to reduce blurring and slice crosstalk.

Results: The method demonstrated good image quality for visualizing dynamic velum movement with reduced blurring and improved image homogeneity. Spatial resolution of 1.2*1.2 mm² with 150 mm FOV and temporal resolution of 20 frames-per-second with simultaneous dual-planar coverage was achieved.

Conclusions: This work describes a new technique for studying speech disorders using dual-planar accelerated spiral dynamic MRI.

Keywords: off-resonance correction; parallel imaging; real-time velum imaging; spiral.