Diffusion-Weighted Imaging-guided MR Spectroscopy in Breast Lesions using Readout-Segmented Echo-Planar Imaging

Abstract

Purpose: To investigate the feasibility and effectiveness of diffusion-weighted imaging (DWI)-guided magnetic resonance spectroscopy (MRS) using readout-segmented echo-planar imaging (RS-EPI) to characterise breast lesions.

Materials and methods: A total of 258 patients with 258 suspicious breast lesions larger than 1 cm in diameter were examined using DWI-guided, single-voxel MRS with RS-EPI. The mean total choline-containing compound (tCho) signal-to-noise ratio (SNR) and concentration were used for the interpretation of MRS data. T-tests, χ(2)-tests, receiver operating characteristic (ROC) curve analyses and Pearson correlations were conducted for statistical analysis.

Results: Histologically, 183 lesions were malignant, and 75 lesions were benign. Both the mean tCho SNR and concentration of malignant lesions were higher than those of benign lesions (6.23 ± 3.30 AU/mL vs. 1.26 ± 1.75 AU/mL and 3.17 ± 2.03 mmol/kg vs. 0.86 ± 0.83 mmol/kg, respectively; P < 0.0001). For a tCho SNR of 2.0 AU/mL and a concentration of 1.76 mmol/kg, the corresponding areas under the ROC curves were 0.93 and 0.90, respectively. The mean tCho SNR and concentration negatively correlated with apparent diffusion coefficients calculated from RS-EPI, with correlation coefficients of -0.54 and -0.48, respectively.

Conclusion: DWI-guided MRS using RS-EPI is feasible and accurate for characterising breast lesions.

Key points: • The mean tCho SNR and concentration negatively correlated with ADCs. • DWI-guided MRS using RS-EPI is feasible. • DWI-guided MRS using RS-EPI accurately characterises breast lesions.

Keywords: Breast lesion; Choline; Diagnosis; Diffusion-weighted magnetic resonance imaging; Magnetic resonance spectroscopy.