Abstract
Purpose: Validation of the efficacy of decompression surgery in patients with cervical myelopathy (CM) is important in terms of the recovery of the integrity of the spinal cord. However, to date, no longitudinal study has addressed the underlying pathological changes using diffusion tensor imaging (DTI) in CM patients. This study aimed to determine the diffusion metrics at the lesion as well as below the lesion level longitudinally in CM patients following laminoplasty using DTI.Methods: Twenty CM patients were analyzed and compared with 20 age-matched healthy controls. The primary outcome measure was the changes in the diffusion metrics [fractional isotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD)]. The secondary outcome measure was the changes in the modified Japanese Orthopedic Association (mJOA) score. Diffusion metrics obtained from six region-of-interests (ROIs; 2 anterior, 2 posterior, 2 lateral) at the lesion and below the lesion level (C7/T1) in preoperative and 6 months postoperative conditions were compared longitudinally.Results: The CM patients showed significant changes in their postoperative diffusion metrics for the anterior ROIs compared with the preoperative measures both at and below the lesion level. In the lateral and posterior cord, the preoperative AD value decreased after laminoplasty to the control at the lesion level. In contrast, MD and RD values at the lesion level and FA value at below the lesion level remained unchanged postoperatively. In addition, the postoperative anterior FA value was positively correlated with the postoperative mJOA score below the lesion level.Conclusion: This would be the first study showing changes in the spinal cord at the lesion as well as below the lesion level after laminoplasty in CM patients, which may be associated with functional recovery.
Highlights
Cervical myelopathy (CM) is a common age-related disorder that presents symptoms of unsteady gait, worsening balance, clumsy hands, spasticity, and voiding difficulty, which often progressively leads to motor paralysis and sensory disturbances [1].Currently, magnetic resonance imaging (MRI) plays an essential role in the diagnosis and follow-up of spinal cord lesions
One of the reasons about the discrepancy between MRI and clinical findings is suggested by an asymptomatic period that could last for many years, which means that potential changes have taken place in the spinal cord as a result of adjusting to pathological changes during that period [6, 7]
diffusion tensor imaging (DTI) analysis is based on the diffusion properties of the water molecules, which can be presented in a diffusion metrics that shows the directionality in a relative value between 0 and 1 (FA) [11], and the total amount of diffusivity (MD), which is the sum of the axial (AD), and horizontal diffusivity (RD)
Summary
Cervical myelopathy (CM) is a common age-related disorder that presents symptoms of unsteady gait, worsening balance, clumsy hands, spasticity, and voiding difficulty, which often progressively leads to motor paralysis and sensory disturbances [1].Currently, magnetic resonance imaging (MRI) plays an essential role in the diagnosis and follow-up of spinal cord lesions. There is a substantial disagreement about the discrepancy between MRI and clinical findings [2,3,4,5]. One of the reasons about the discrepancy between MRI and clinical findings is suggested by an asymptomatic period that could last for many years, which means that potential changes have taken place in the spinal cord as a result of adjusting to pathological changes during that period [6, 7]. Validation of the efficacy of decompression surgery in CM patients has always been a matter of great interest regarding the recovery of the spinal cord integrity; it has not been tackled sufficiently due to the technical difficulties in assessments of those pathological changes. Recent advances in the diffusion tensor imaging (DTI) technology have enabled the measurement of white matter fiber integrity both quantitatively and qualitatively. The FA value is generally considered closely related to the function [12] and decreased FA could implicate a reduced number of fibers or a reduced density results in increased extracellular space [13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
