IVIM perfusion fraction is prognostic for survival in brain glioma.

Introduction: The interest in measuring brain perfusion with intravoxel incoherent motion (IVIM) MRI has significantly increased in the last 3 years. Our aim was to evaluate the prognostic value for survival of intravoxel incoherent motion perfusion fraction in patients with gliomas, and compare it to dynamic susceptibility contrast relative cerebral blood volume and apparent diffusion coefficient.
Methods: Images were acquired in 27 patients with brain gliomas (16 high grades, 11 low grades), before any relevant treatment. Region of maximal perfusion fraction, maximal relative cerebral blood volume, and minimal apparent diffusion coefficient were obtained. The accuracy of all three methods for 2‑year survival prognosis was compared using the area under the receiver operating characteristic curve and Kaplan-Meier survival curves.
Results: Death or survival for at least 2 years after imaging could be documented in 22/27 patients. The cutoff values of 0.112 for the perfusion fraction, of 3.01 for the relative cerebral blood volume, and 1033 × 10 ^-6  mm ² /s for apparent diffusion coefficient led to an identical sensitivity of 0.889, and a specificity of 0.833, 0.517, and 0.750, respectively for 2 year survival prognosis. The corresponding areas under the receiver operating characteristic curves were 0.84, 076, and 0.86, respectively. All three methods had a significant log rank test considering overall survival (p = 0.001, p = 0.028, and p = 0.002).
Conclusion: In this relatively small cohort, maximal IVIM perfusion fraction, similarly to maximal relative cerebral blood volume and minimal apparent diffusion coefficient, was prognostic for survival in patients with gliomas. Maximal IVIM perfusion fraction and minimal apparent diffusion coefficient performed similarly in predicting survival, and both slightly outperformed maximal relative cerebral blood volume.