High-Contrast Lumbar Spinal Bone Imaging Using a 3D Slab-Selective UTE Sequence.

Michael Carl,Jiyo Athertya,Amir Masoud Afsahi,Zhao Wei,Roland R. Lee,Mark Wallace,Koichi Masuda,Alecio F. Lombardi,Ya-Jun Ma

doi:10.3389/fendo.2021.800398

Abstract

Ultra-short echo time (UTE) MRI with post-processing is a promising technique in bone imaging that produces a similar contrast to computed tomography (CT). Here, we propose a 3D slab-selective ultrashort echo time (UTE) sequence together with image post-processing to image bone structures in the lumbar spine. We also explore the intermodality agreement between the UTE and CT images. The lumbar spines of two healthy volunteers were imaged with 3D UTE using five different resolutions to determine the best imaging protocol. Then, four patients with low back pain were imaged with both the 3D UTE sequence and CT to investigate agreement between the imaging methods. Two other patients with low back pain were then imaged with the 3D UTE sequence and clinical conventional T1-weighted and T2-weighted fast spin-echo (FSE) MRI sequences for qualitative comparison. The 3D UTE sequence together with post-processing showed high contrast images of bone and high intermodality agreement with CT images. In conclusion, post-processed slab-selective UTE imaging is a feasible approach for highlighting bone structures in the lumbar spine and demonstrates significant anatomical correlation with CT images.

Highlights

Spinal disorders are a major medical, social, and economic issue due to their high prevalence and increasing incidence, especially among the elderly [1]
We investigated the performance of a 3D slabselective Ultra-short echo time (UTE) sequence together with signal post-processing to image bone structures in the lumbar spine in comparison with computed tomography (CT)
The focus measure of the slabselective UTE image shows a value about 2.5x higher value than that of the non-slab-selective image in the lumbar vertebral bone region, demonstrating that the slab-selective UTE acquisition produces better bone sharpness than the non-slab-selective acquisition due to its greater capability to alleviate the interference of respiratory motion artifacts

Summary

Introduction

Spinal disorders are a major medical, social, and economic issue due to their high prevalence and increasing incidence, especially among the elderly [1]. Zero echo time (ZTE) combined with data post-processing [2] has been applied for high contrast bone imaging of the head [3], shoulder [4], cervical spine [5], and hip [6]. Spinal Bone Imaging UTE MRI shortest echo time achievable in the MR system and some coils require a relatively long ring-down time after excitation (between 10 and 200 μs) [7, 8]. Data acquired during this ring-down period may lead to spatial signal inhomogeneity

Methods

Results

Conclusion