Quantitative analysis of intervertebral disc degeneration using Q‐space imaging in a rat model

Abstract

The degree of intervertebral disc (IVD) degeneration is qualitatively evaluated on T2‐weighted imaging (T2WI). However, it is difficult to assess subtle changes in IVD degeneration using T2WI. Q‐space imaging (QSI) is a quantitative diffusion‐weighted imaging modality used to detect subtle changes in microenvironments. This study aimed to evaluate whether QSI can detect the inhibitory effects of the antioxidant N‐acetylcysteine (NAC) in IVD degeneration. We classified female Wistar rats into control, puncture, and NAC groups (n = 5 per group). In the puncture and NAC groups, IVDs were punctured using a needle. The antioxidant NAC, which suppresses the progression of IVD degeneration, was orally administered in the NAC group 1 week prior to puncture. The progression and inhibitory effect of NAC in IVD degeneration were assessed using magnetic resonance imaging (MRI): IVD height, T2 mapping, apparent diffusion coefficient (ADC), and QSI. MRI was performed using a 7‐Tesla system with a conventional probe (20 IVDs in each group). QSI parameters that were assessed included Kurtosis, the probability at zero displacement (ZDP), and full width at half maximum (FWHM). IVD degeneration by puncture was confirmed by histology, IVD height, T2 mapping, ADC, and all QSI parameters (P < .001); however, the inhibitory effect of NAC was confirmed only by QSI parameters (Kurtosis and ZDP: both P < .001; FWHM: P < .01). Kurtosis had the largest effect size (Kurtosis: 1.13, ZDP: 1.06, and FWHM: 1.02) when puncture and NAC groups were compared. QSI has a higher sensitivity than conventional quantitative methods for detecting the progressive change and inhibitory effect of NAC in IVD degeneration.

Imaging Evaluation of Intervertebral Disc Degeneration and Painful Discs—Advances and Challenges in Quantitative MRI

“…DKI has also been shown to be beneficial in detecting microstructural differences of Pfirrmann grade I and II discs in normal rats with relatively high accuracy [82]. Additionally, in a study of the inhibitory effect of the antioxidant N-acetylcysteine on a rat IVD degeneration model, QSI enabled the detection of slight changes that could not be detected by conventional quantitative methods, e.g., T2 mapping and ADC [83]. As such, QSI and DKI form promising techniques for evaluating IVD degeneration and regeneration, although practical considerations do require further development.…”

Exosomes Secreted by Nucleus Pulposus Stem Cells Derived From Degenerative Intervertebral Disc Exacerbate Annulus Fibrosus Cell Degradation via Let-7b-5p

“…Intervertebral disc degeneration (IDD) is one of the main causes of lower back pain, but its specific pathogenesis remains unclear ( Nakashima et al, 2020 ). Surgical treatment can relieve symptoms and alleviate pain, but it has no effect on the underlying disease itself ( Dowdell et al, 2017 ).…”

Deep Learning-Based Magnetic Resonance-Ultrashort Time of Echo Imaging for Analyzing Degeneration of Intervertebral Disc Cartilage Endplate and Rehabilitation Nursing

“…CT examination has obvious advantages in the bone examination due to its short scanning time and high-density resolution, but its soft tissue contrast is poor and it cannot display the structure of cartilage endplate and annulus fibrosus [8]. MR has the advantages of no radiation, high soft tissue resolution, and no overlapping image, showing great potential in the morphology and functional display of intervertebral disc and becoming the main imaging examination method of the lumbar spine [9][10][11][12]. With the continuous progress of imaging technology, magnetic resonance-ultrashort time of echo (MR-UTE) technology can significantly shorten the echo time and collect and display short T2 tissue signals, pointing out a new research path for DIDCE [13].…”