Optimization of intravoxel incoherent motion (IVIM): variability of parameters measurements using a reduced distribution of b values for breast tumors analysis.

OBJECTIVES: This study aimed to examine the variability of intravoxel incoherent motion measurements acquired from reduced distributions of b values for breast tumors analysis.
MATERIALS AND METHODS: The investigations were carried out on twenty-four patients with diagnosed breast tumors. A conventional unenhanced MRI and various IVIM series preset with different distributions of b values (0-1000 s/mm2) were performed. We assessed the variability in Dslow, Dfast, and PF measurements for different distributions of 9 to 4 b values compared with the IVIM metrics for 10 b values using Wilcoxon-Signed rank test. The data was statistically significant at P < 0.05.
RESULTS: The results showed no significant variation in the estimations of IVIM parameters in patients. However, the measurements acquired with the combination of 5 b values Showed some variation in Dfast (P = 0.028) compared with 10 b values. The data showed high wCVs in the measurements acquired using the reduced set of 6 b values for Dslow and PF and with the combination of 7 b values for Dfast. There were inconsistencies noticed in the measurements acquired from malignant tumors using reduced distributions of b values (9 b values-4 b values). However, the set of 4 b values displayed the lowest wCVs for both benign and malignant datasets. We also observed unsystematic correlations among different combinations of b values in the categories of IVIM parameters.
CONCLUSION: There was no relevant variation in the parameters measurements irrespective of the number of b values used. Reduced distributions of b values may find use in estimations of IVIM parameters for breast lesions analysis.