Axial MR diffusion tensor imaging and tractography in clinical diagnosed and pathology confirmed cervical spinal cord astrocytoma

- FA value of cervical spinal cord astrocytoma decreased, but ADC value increased.
- FA imaging was more sensitive to discrete solid spinal cord astrocytoma.
- DTI was sensitive for the evaluation of microstructure pathological changes.
- On DTT, cervical spinal cord astrocytomas can be subdivided into Type I and Type II.
- DTT can be used to guide operation planning.

ObjectiveTo evaluate the diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) features of cervical spinal cord astrocytoma.MethodsEleven patients with cervical spinal cord astrocytomas and 10 healthy volunteers were recruited in this study. Conventional magnetic resonance imaging (MRI) and axial DTI were performed on a 3.0T MRI system. Apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values for the lesions were measured. DTT was performed using the principal diffusion direction method.ResultsADC values of the lesions and the normal-appearing tissue around the tumour (NATAT) on T2-weighted imaging (T2WI) increased. The ADC values of the lesions were higher. The FA values of the lesions and the NATAT decreased significantly, with the lesions having lower FA values. The RD value (1.36 ± 0.49) of the tumours was significantly higher than those found in the healthy controls, but similar for the AD value (1.84 ± 0.56). There were no differences in ADC or FA values between lesions and NATAT in McCormick Type I vs. Type II patients. Based on the DTT, 7 patients with solid mass tumours were classified as Type I. One patient with a solid mass, 2 patients with cystic degeneration inside the lesions, and 1 patient with a cyst around the mass were classified as Type II.ConclusionsFA values of the cervical spinal cord astrocytoma decreased, but the ADC values increased. DTI was sensitive for the evaluation of pathological changes that could not be visualized on T2WI. Our preliminary study indicates that DTT can be used to guide operation planning, and that axial images of DTT may be more valuable.