Contrast enrichment of spinal cord MR imaging using a ratio of T1-weighted and T2-weighted signals.

PURPOSE: We aimed to assess if the T1-weighted (T1w)/T2-weighted (T2w) signal ratio could be used to improve image contrast in MR spinal cord imaging.

MATERIALS AND METHODS: T1w and T2w cervical spinal cord MR images were acquired from 23 normal subjects using 3 Tesla (T) MR scanner. In addition, a multiple sclerosis patient, and a cervical spondylotic myelopathy patient were evaluated. White matter (WM) and gray matter (GM) signal intensities were measured for each image (T1w, T2w, and T1w/T2w) for seven cervical segments in each subject to calculate the contrast. Age-related changes in signal intensity were assessed at each location (lateral column, anterior column, dorsal column, and GM) for each image. Additionally, the imaging results of two subjects with spinal diseases and the controls were numerically compared.

RESULTS: The contrast between the WM and GM in the T1w/T2w ratio image was approximately twice as much as that in the T1w and T2w images (mean ± SD = 1.8 ± 0.4). The signal intensity ratio was related to age. For both clinical patients, the signal intensities were significantly lower in the lesion areas in the ratio images.

CONCLUSION: The T1w/T2w ratio images demonstrated increased image contrast compared with T1w and T2w images alone and, reduced inter-individual signal intensity differences.