The MRI method can track disc changes

In her presentation, Dr. Frida Johansson of the University of Gothenburg in Sweden supported her team’s research, which found that intervertebral disc deformation (IVD) in the spine depends on disc degeneration and lumbar spine height. The team used a technique called deformation field MRI for their findings.

“Deformation field MRI appears to be a promising tool to study the degenerative process of the intervertebral disc and could be useful in evaluating painful disc disease,” said Johansson.

The ISMRM is co-hosting this week’s meeting with the European Society for Magnetic Resonance in Medicine and Biology and the International Society for MR Radiographers and Technologists.

distribute load

The intervertebral disc distributes the pressure load on the spine and acts as a shock absorber. Disc tissue degenerates during the aging process, causing the disc to lose its ability to withstand pressure. This in turn leads to increased back pain.

It remains unknown how the IVD responds to mechanical stimuli in vivo. Johansson said that extracorporeal experiments cannot fully replace in vivo studies because they do not take into account the disc’s natural environmental factors, such as: B. Spinal placement, muscles surrounding the disc, disc angle, and spinal curvature. In vivo studies could provide better insight into IVD pathophysiology and improve spine diagnostics, she added.

MRI is a non-ionizing and non-invasive tool that could be used for in vivo assessment. Johansson said that an MRI performed during axial loading of the spine could reveal important intradiscal deformation patterns.

Johansson and colleagues wanted to find out how the lumbar IVD structure deforms during spinal loading in vivo. They used a novel, non-invasive method that leveraged MRI and image registration to quantify their data.

The researchers collected MR images of the lumbar spine from 24 patients with chronic low back pain and 12 control patients using a 1.5 Tesla MRI scanner. They also collected T2-weighted images with the spine in unloaded and loaded states to study IVD properties at different spine levels.

Research presented at the annual ISMRM indicates that a novel MRI registration method can noninvasively track changes in intervertebral discs while characterizing intervertebral disc structures. These images are used to create heat maps showing compression at different parts of the spine. Image courtesy of Dr. Frida Johanson.

Lumbar spine images acquired during axial loading were rigidly and non-rigidly transformed into corresponding unloaded T2-weighted MR images. Registration was performed by a rigid Euler transform and a non-rigid B-spline transform.

The team found differences in deformation for different levels of the spine. Johansson said that IVDs showed more compression at the lower lumbar levels (p

The novel imaging technique revealed regional deformation variations across the IVD. Researchers generally found more compression in the center of the IVD and a slightly leftward asymmetric pattern. They also found that IVDs with advanced degeneration exhibited greater posterior compression (p=0.035-0.045) even when spinal height was corrected. These were more commonly found in the lower lumbar spine.

The team also noted the presence of asymmetries in the deformation pattern across the IVDs. They wrote that this was “most likely” caused by the disc height differential across the IVD.

Johansson added that no significant difference in deformity was found between patients and controls.

The team concluded that while deformation field MRI cannot differentiate between symptomatic patients and asymptomatic controls at the group level, when combined with conventional MRI markers, it can provide an individualized diagnosis.

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