Comparison of intravoxel incoherent motion diffusion-weighted imaging between turbo spin-echo and echo-planar imaging of the head and neck.

OBJECTIVES

To compare image quality, apparent diffusion coefficient (ADC), and intravoxel incoherent motion (IVIM)-derived parameters between turbo spin-echo (TSE)-diffusion-weighted imaging (DWI) and echo-planar imaging (EPI)-DWI of the head and neck.

METHODS

Fourteen volunteers underwent head and neck imaging using TSE-DWI and EPI-DWI. Distortion ratio (DR), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), ADC and IVIM-derived parameters were compared between the two techniques. Bland-Altman analysis was performed to analyse reproducibility between the quantitative parameters of TSE-DWI and EPI-DWI.

RESULTS

DR of TSE-DWI was significantly smaller than that of EPI-DWI. SNR and CNR of TSE-DWI were significantly higher than those of EPI-DWI. ADC and IVIM-derived parameters of TSE-DWI showed higher values than those of EPI-DWI, although the difference was not significant. Bland-Altman analysis showed wide limits of agreement between the two sequences.

CONCLUSION

TSE-DWI can produce better image quality than EPI-DWI, while TSE-DWI possibly exhibits different values of quantitative parameters. Therefore, TSE-DWI could be a good alternative to EPI-DWI for patients sensitive to distortion. However, it is not recommended to use both TSE-DWI and EPI-DWI on follow-up.

KEY POINTS

• Head and neck DWI is especially sensitive to magnetic inhomogeneity. • The distortion of images was less with TSE-DWI than with EPI-DWI. • TSE-DWI can possibly exhibit higher ADC and IVIM-derived parameters than EPI-DWI. • Bland-Altman analysis showed unacceptable LoA in quantitative analysis between TSE-DWI and EPI-DWI. • It is not recommended to use both TSE-DWI and EPI-DWI for follow-up.