Lightning Podiums: Spinal Gumbo - 803A

Presented by: W. Tian

Author(s):

W. Tian(1), J. Wang(1), X. Han(1), D. Li(1), G. Li(2), Q. Song(1)

(1) Fourth Clinical Medical College of Peking University, Beijing Jishuitan Hospital, Department of Spine Surgery, Beijing, China
(2) Tsinghua University, Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Beijing, China

Abstract

Background data: Neurite orientation dispersion and density imaging (NODDI) is a biophysically plausible models providing parameters such as intra-cellular volume fraction (Vicf), describing neurite density, and orientation dispersion index (ODI), describing neurite orientation dispersion. Therefore, NODDI disentangles two key contributing factors of fractional anisotropy (FA), an important parameter of diffusion tensor imaging (DTI), which was thought to be correlated with spinal cord function.

Purpose: To investigate the relationship between FA, Vicf, ODI and spinal cord states of postoperative degenerative cervical myelopathy (DCM) patients.

Study Design: A retrospective cohort study. Subjects and

Methods: A follow-up study was carried out using DTI and NODDI. 59 postoperative DCM patients who were 222 to 727 days after surgery were recruited. JOA scale was used to assess spinal function status. FA, Vicf, and ODI were measured at levels of maximal compression (LMC) of patients. Spearman's correlation was used to test the relationship between the parameters and JOA score.

Results: NODDI parameters Vicf and ODI were significantly correlated with DTI parameter FA (ρ=0.547, -0.423 separately; P<0.01). FA and Vicf were significantly correlated with JOA score (ρ=0.429, 0.397 separately; P<0.01), while ODI was not.

Conclusions: The correlation results confirmed that lower neurite density or greater orientation dispersion lead to lower diffusion anisotropy in postoperative DCM patients. For decompressed spinal cord, the underlying reason for the reduced spinal cord function states may be the decreased fiber density, not increased dispersion of fiber orientations.