Prognostic Value of Diffusion Tensor Imaging and fMRI in Surgical Management of Cervical Myelopathy

Cervical myelopathy (CM) is the most common cause of spinal cord dysfunction in the elderly. Symptoms often develop insidiously and are characterized by neck stiffness, arm pain, numbness in the hands, and weakness of the hands and legs. The causes of this myelopathy are many, such as spinal canal narrowing, osteophytes, herniated discs and hypertrophy of the ligamentum flavum. Although the clinical signs and symptoms of CM are well documented in the literature, a precise localization of the maximum level of compression is sometimes difficult in the elderly patients where multiple levels of the cervical spine are degenerated. Also the lack of understanding of the pathophysiology and pathomechanism of CM has significantly hampered the development of a rational approach to the surgical treatment of such condition.

The diagnosis is made based on clinical signs and symptoms with the help of conventional MRI imaging which demonstrates the levels of anatomical stenosis. Surgical decompression of the cervical spine is the most common form of treatment. Magnetic resonance imaging (MRI) has been used widely in the evaluation of patients with CM. The commonly applied MR techniques include spin echo sequence, both conventional spin echo and fast/turbo spin echo for T1 and T2 information; gradient echo sequences, which generate T2 images; STIR (short tau inversion recovery) images; fat suppressed T1 images; gadolinium enhanced images applied to either routine T1WIs or fat suppressed T1WIs; MR spinal angiography; and cerebrospinal fluid flow (CSF) studies (either magnitude or phase contrast). However, conventional MRI mainly concerns anatomical information about CM, with less pathophysiological information. BOLD-fMRI is able to present the activated neuronal volume decreased in CM patients along with an increase in neuronal activities. diffusion tensor imaging (DTI) permits the detection of tissue-water molecular diffusion at microscopic dimensions. Previous studies have demonstrated the feasibility of DTI in evaluating microstructural changes in the myelopathic cervical cord. The prognostic values of spinal cord DTI in CM have been addressed in several previous studies. In recent years, combination of DTI and fMRI has been proposed to be an accurate prognostic tool for surgical management of CM.

Cervical myelopathy (CM) is caused by degenerative stenosis of the cervical spine with progressive compression on the spinal cord resulting in loss of sensory and motor functions in the upper and lower limbs. Surgical decompression of the cervical spine is the most common form of treatment.

The objective of this project is to evaluate the value of DTI and fMRI in predicting the outcome of surgical treatment.