New MRI technology a leap forward for diagnosing degenerative disc disease of the spine
A recent study by the Department of Orthopaedics and Traumatology, The University of Hong Kong (HKU) showed that ultra-short time-to-echo disc sign (UDS) obtained from ultra-short time-to-echo (UTE) MRI is significantly related to degenerative spine changes, low back pain (LBP) and disability in degenerative disc disease of the spine.
In the cross-sectional study of 108 Southern Chinese participants where T2-weighted MRI was used to assess disc degeneration, 39.8 percent of patients demonstrated UDS. The presence of UDS was significantly correlated to disc degeneration, disc bulges/protrusions, modic changes and spondylolisthesis (p≤0.05). [Spine (Phila Pa 1976) 2017, doi: 10.1097/BRS.0000000000002369]
The UDS score was significantly correlated with worse Oswestry Disability Index (ODI) scores (r=0.311; p=0.001) and pain (p=0.009), whereas T2-weighted cumulative disc degeneration score was not (ODI: r=0.13; p=0.19) (LBP: p=0.127).
Furthermore, 39.5 percent of participants with UDS who had multilevel involvement also had a higher prevalence of LBP (p<0.015).However, this correlation was not found on T2-weighted MRI (p=0.53).
The UDS was defined by the HKU group as a hyper- or hypo-intense band located within the disc. A UDS score can be calculated as the cumulative number of UDS levels.
“Conventional T2-weighted MRI has traditionally been used to assess spine degeneration, but this was not strongly correlated to LBP or disability... Our study provides the ‘missing link’ between imaging findings of the spine and the development of LBP and disability,” said investigator Dr Dino Samartzis of the Department of Orthopaedics and Traumatology, HKU.
“The assessment of UDS may supplement conventional MRI, providing a larger snapshot into a patient’s spine degeneration and pain profiles, which allows clinicians to develop more precise management options to improve patient outcomes. This certainly represents a new leap forward in the visualization of spinal discs and perhaps pain,” Samartzis added.
“UTE MRI is the only sequence in our study that showed definite correlation between back pain, disability and degenerative disc changes of the spine. This may promote further understanding in the pathologies and therapies for LBP and lumbar degeneration,” investigator Dr Henry Pang of the Li Ka Shing Faculty of Medicine, HKU, emphasized.
“Further studies are necessary to determine the true role of the UDS in the disease process. Larger, prospective and multicentre studies are needed to further validate our findings and assess the utility of the UDS on different clinical and research platforms,” the authors added.
UTE MRI assesses MRI signals from short T2 components that are not detected on conventional T2-weighted MRI. It has never been reported to assess disc changes and their clinical relevance. The HKU group was the first to identify UDS as a new disc phenotype from UTE, which could serve as a new imaging marker for degenerative disc disease.