Assessment of intervertebral disc degeneration based on quantitative magnetic resonance imaging analysis: an in vivo study. Academic Article uri icon

Overview

MeSH

  • Algorithms
  • Animals
  • Disease Models, Animal
  • Image Interpretation, Computer-Assisted
  • Male
  • Observer Variation
  • Predictive Value of Tests
  • Rats
  • Rats, Nude
  • Reproducibility of Results
  • Severity of Illness Index
  • Time Factors

MeSH Major

  • Intervertebral Disc
  • Intervertebral Disc Degeneration
  • Magnetic Resonance Imaging

abstract

  • Animal experimental study. To evaluate a novel quantitative imaging technique for assessing disc degeneration. T2-relaxation time (T2-RT) measurements have been used to assess disc degeneration quanti-tatively. T2 values correlate with the water content of intervertebral disc tissue and thereby allow for the indirect measurement of nucleus pulposus (NP) hydration. We developed an algorithm to subtract out magnetic resonance imaging (MRI) voxels not representing NP tissue on the basis of T2-RT values. Filtered NP voxels were used to measure nuclear size by their amount and nuclear hydration by their mean T2-RT. This technique was applied to 24 rat-tail intervertebral discs (IVDs), which had been punctured with an 18-gauge needle according to different techniques to induce varying degrees of degeneration. NP voxel count and average T2-RT were used as parameters to assess the degeneration process at 1 and 3 months postpuncture. NP voxel counts were evaluated against radiograph disc height measurements and qualitative MRI studies on the basis of the Pfirrmann grading system. Tails were collected for histology to correlate NP voxel counts to histological disc degeneration grades and to NP cross-sectional area measurements. NP voxel count measurements showed strong correlations to qualitative MRI analyses (R = 0.79, P < 0.0001), histological degeneration grades (R = 0.902, P < 0.0001), and histological NP cross-sectional area measurements (R = 0.887, P < 0.0001).In contrast to NP voxel counts, the mean T2-RT for each punctured group remained constant between months 1 and 3. The mean T2-RTs for the punctured groups did not show a statistically significant difference from those of healthy IVDs (63.55 ms ± 5.88 ms mo 1 and 62.61 ms ± 5.02 ms) at either time point. The NP voxel count proved to be a valid parameter to assess disc degeneration quantitatively in a needle puncture model. The mean NP T2-RT does not change significantly in needle-puncture-induced degenerated IVDs. IVDs can be segmented into different tissue components according to their innate T2-RT.

publication date

  • March 15, 2014

has subject area

  • Algorithms
  • Animals
  • Disease Models, Animal
  • Image Interpretation, Computer-Assisted
  • Intervertebral Disc
  • Intervertebral Disc Degeneration
  • Magnetic Resonance Imaging
  • Male
  • Observer Variation
  • Predictive Value of Tests
  • Rats
  • Rats, Nude
  • Reproducibility of Results
  • Severity of Illness Index
  • Time Factors

Research

keywords

  • Journal Article

Identity

Language

  • eng

Digital Object Identifier (DOI)

  • 10.1097/BRS.0000000000000194

PubMed ID

  • 24384655

Additional Document Info

start page

  • E369

end page

  • E378

volume

  • 39

number

  • 6