Values of apparent diffusion coefficients in staging the lesions of multiple sclerosis

Abstract

Objective To explore the values of apparent diffusion coefficients(ADC) in staging the lesions of multiple sclerosis(MS) through analysing the differences of ADC in different types of lesions. Methods 137 lesions identified in 29 patients with MS, were characterized by their enhancement pattern on contrast-enhanced T1-weighted MR images and whether they were changing in appearance, size or signal. The lesions were classified into four groups: homogeneously enhancing lesions (HELs), ring-enhancing lesions (RELs), active nonenhancing lesions (ANELs), and inactive nonenhancing lesions(INELs). The mean ADC values for each type of lesions were calculated and compared. Results The ADC values for HELs, RELs, ANELs and INELs were (91.09±13.63)×10-5·m2·s-1, (105.66±9.92)×10-5·m2·s-1, (136.80±20.31)×10-5·m2·s-1 and (127.46±13.65)×10-5·m2·s-1. There were significant differences between the ADC values of any two groups in the four groups except the ADC values between ANELs and INELs. Conclusion ADC values are useful to differentiate each type of lesion, which can help stage the lesions of MS. Key words: Multiple sclerosis; Lesion staging; Apparent diffusion coefficients; Diffusion-weighted imaging