Vol.:(0123456789) 1 3 Magnetic Resonance Materials in Physics, Biology and Medicine https://doi.org/10.1007/s10334-019-00779-7 RESEARCH ARTICLE Optimization of intravoxel incoherent motion (IVIM): variability of parameters measurements using a reduced distribution of b values for breast tumors analysis Natacha Raissa Doudou 1,2  · Yajie Liu 2  · Sylvanus Kampo 3  · Kai Zhang 2  · Yue Dai 2  · Shaowu Wang 1,2 Received: 14 January 2019 / Revised: 13 September 2019 / Accepted: 17 September 2019 © European Society for Magnetic Resonance in Medicine and Biology (ESMRMB) 2019 Abstract 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 con- ventional unenhanced MRI and various IVIM series preset with diferent distributions of b values (0–1000 s/mm 2 ) were per- formed. We assessed the variability in D slow , D fast, and PF measurements for diferent 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 signifcant at P < 0.05. Results The results showed no signifcant variation in the estimations of IVIM parameters in patients. However, the measure- ments acquired with the combination of 5 b values Showed some variation in D fast (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 D slow and PF and with the combination of 7 b values for D fast . 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 diferent 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 fnd use in estimations of IVIM parameters for breast lesions analysis. Keywords Intravoxel incoherent motion · Magnetic resonance imaging · Breast neoplasms Introduction Difusion magnetic resonance imaging (MRI) is a useful tool which is applied in oncology for diagnosis, staging, and monitoring of cancer proliferation, and evaluation of a treatment efect in cancer patients [1–3]. The potential of the bi-exponential model of intravoxel incoherent motion (IVIM) difusion-weighted imaging (DWI) to provide non- invasively information about difusion and perfusion in the living body have been widely studied for medical purposes. Several studies have reported its clinical values in oncology for the examinations of various regions of the human body [4–8]. The use of IVIM sequence in MRI analysis of the breast lesions includes the tumors characterization, the dif- ferentiation between malignant and benign lesions [9–14], and the monitoring of responses to therapy [3, 15]. Le Bihan et al., in 1986 proposed the IVIM bi-exponential model and described a relationship between the signal decay, the b value, and IVIM derived parameters which indirectly established a connection between IVIM parameters and b values [16]. Existing evidence indicate that including low b values (b < 200 s/mm 2 ) in a distribution improve the esti- mation of perfusion-related parameters [17, 18]. However, Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10334-019-00779-7) contains supplementary material, which is available to authorized users. * Shaowu Wang wsw_2018@163.com 1 Department of Radiology, Dalian Medical University, Dalian, China 2 Department of Radiology, The Second Afliated Hospital of Dalian Medical University, Dalian, China 3 Department of Anesthesiology, Dalian Medical University, Dalian, China