Cerebral perfusion measurement in brain death with intravoxel incoherent motion imaging

Abstract

Background: The assessment of brain death can be challenging in critically ill patients, and cerebral perfusion quantification might give information on the brain tissue viability. Intravoxel incoherent motion perfusion imaging is a magnetic resonance imaging technique, which extracts perfusion information from a diffusion-weighted sequence, and provides local, microvascular perfusion assessment without contrast media injection. Methods: Diffusion weighted images were acquired with 16 b-values (0-900 s/mm 2 ) in the brain in two patients with cerebral death, confirmed by clinical assessment and evolution, as well as in two age-matched healthy subjects. The intravoxel incoherent motion perfusion fraction maps were obtained by fitting the bi-exponential signal equation model. 8 regions of interest were drawn blindly in the brain neocortex (in the frontal, temporal, parietal, and occipital lobes on both sides) and perfusion fractions were compared between patients with cerebral death and healthy control. Statistical significance was assessed using two-sided Wilcoxon signed rank test, and set to α < 0.05. Results: Intravoxel incoherent motion (IVIM) perfusion fraction was vanishing in the brain of the two patients with cerebral brain death compared to the healthy controls. Mean (± standard deviation) cortex perfusion fraction was 0.016 ± 0.005 respectively 0.005 ± 0.008 in the cerebral death patients, compared to respectively 0.052 ± 0.021 (p = 0.02) and 0.071 ± 0.042 (p = 0.008) in the age-matched controls. Conclusion: Intravoxel incoherent motion perfusion imaging is a promising tool to assess local brain tissue viability in critically ill patients.

Intravoxel incoherent motion MRI as a means to measure in vivo perfusion: A review of the evidence

“…In acute stroke in the brain, a significant decrease in f was measured in the infarct core compared with the contralateral hemisphere in three independent studies. 41,81,83 In addition, in two patients with cerebral brain death, lack of cerebral perfusion could be demonstrated with IVIM, 84 while the perfusion of the territory of the external carotid artery was retained, in accordance with findings with other modalities 85 and with IVIM in rats. 86 To our knowledge IVIM has not been applied in strokes in any other organs than the brain.…”

Signal to noise and b-value analysis for optimal intra-voxel incoherent motion imaging in the brain

“…A relatively large amount of experimental evidence consistent with the interpretation that the IVIM method can provide in vivo perfusion information has been collected in the last few years [ 2 ]. In particular, the IVIM method has been shown to be applicable in a broad range of brain clinical investigations [ 3 ], both in the context of hyperperfused lesions such as in high-grade glioma [ 4 – 12 ], and hypoperfused lesions such as strokes [ 13 – 16 ], vasospasm [ 17 ], cerebral lymphoma [ 18 ] and cerebral death [ 19 ]. In addition, the method has shown promise for the survival prognosis in high-grade brain glioma [ 20 , 21 ], in differentiating recurrent tumor from radiation necrosis for brain metastases treated with radiosurgery [ 22 ], and as a surrogate marker for the progression of cerebral small vessel disease [ 23 , 24 ].…”

“…A relatively large amount of experimental evidence consistent with the interpretation that the IVIM method can provide in vivo perfusion information has been collected in the last few years (Christian Federau, 2017). In particular, the IVIM method has been shown to be applicable in a broad range of brain clinical investigations , both in the context of hyperperfused lesions such as in high-grade glioma (Bisdas, 2013;Catanese et al, 2018;Gielen et al, 2017;Keil et al, 2015;Shen et al, 2016;Togao et al, 2016;Wang et al, 2019;Zou et al, 2018), and hypoperfused lesions such as strokes (C. Christian Federau et al, 2019;Suo et al, 2016;Yao et al, 2016), vasospasm (Heit et al, 2018), cerebral lymphoma (Yamashita et al, 2016) and cerebral death (Christian Federau et al, 2016). In addition, the method has shown promises for the survival prognosis in high-grade brain glioma Puig et al, 2016), in differentiating recurrent tumour from radiation necrosis for brain metastases treated with radiosurgery (Detsky et al, 2017), and as a surrogate marker for the progression of cerebral small vessel disease (Sau May Wong et al, 2017;Zhang et al, 2017).…”

Intravoxel Incoherent Motion Quantification Dependent on Measurement SNR and Tissue Perfusion: A Simulation Study

“…IVIM imaging is very powerful because it not only provides the information of classic diffusion imaging accurately, but also extracts information about perfusion imaging. Several clinical and simulation studies have shown that IVIM imaging is a promising technique to diagnose abnormalities in brain, liver, kidney, breast, and prostate [5][6][7][8][9][10]. There is no need for exogenous contrast agent injection to extract IVIM perfusion information, which is the main limitation of classical perfusion MRI.…”