Application of IVIM in the assessment of the spleen in patients with myelofibrosis

Aim: The purpose of this study is to investigate whether IVIM-derived spleen parameters including the true diffusion coefficient (D) and perfusion fraction (f) can serve as non-invasive biomarkers to predict fibrotic transformation of the bone marrow. Methods: Eighteen patients with MPN and 18 healthy controls (HC) underwent abdominal IVIM diffusion-weighted imaging using 1.5 T MR unit. The values of spleen parameters of D and f were compared between patients with various forms of MPN, including 8 patients with myelofibrosis (MF), 10 patients without myelofibrosis (non-MF) and (HC). A Bayesian approach was adopted in the analysis, to assess whether the D and f coefficients, along with the spleen volume, can predict disease occurrence. Results: Comparing MF patients to HC, Bayesian analysis provided strong evidence for a difference in the f parameter (BF = 18.38), while the difference between MF and non-MF patients was weaker (BF = 1.42). There was no statistically significant difference between non-MF and HC (BF = 0. 64). There was no correlation between f parameter and spleen volume (CI= -0,43; 0,38). Logistic regression analysis with logkit function confirmed that f parameter was significant predictor of MF. Conclusions: The study demonstrates that IVIM measurements of spleen perfusion in both healthy individuals and MPN patients offer valuable predictive information regarding disease development and progression. The f parameter shows promise for predicting fibrotic transformation of the bone marrow in MPN patients regardless of the size of the spleen.