Author/Authors :
Hara, Shoko Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Hori, Masaaki Department of Radiology - Juntendo University, Tokyo, Japan , Ueda, Ryo Department of Radiology - Juntendo University, Tokyo, Japan , Hagiwara, Akifumi Department of Radiology - Juntendo University, Tokyo, Japan , Hayashi, Shihori Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Inaji, Motoki Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Tanaka, Yoji Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Maehara, Taketoshi Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Ishii, Kenji Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Aoki, Shigeki Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan , Nariai, Tadashi Department of Neurosurgery - Tokyo Medical and Dental University, Tokyo, Japan
Abstract :
Background
Intravoxel incoherent motion magnetic resonance imaging (IVIM) enables non-invasive measurement of brain perfusion.
Purpose
To investigate whether IVIM could be used to evaluate the hemodynamic disturbance of Moyamoya disease (MMD) by comparison with the gold-standard 15O-gas positron emission tomography (PET) method.
Material and Methods
Ten consecutive patients with MMD (six women; mean age = 42.8 years) and 10 age-matched healthy controls were evaluated by diffusion-weighted images with 12 different b values in the range of 0–900 s/mm2 and 15O-gas PET. Tomographic maps of IVIM parameters, perfusion fraction (f ), pseudo-diffusion coefficient (D*), and f・D*, as well as cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) maps obtained with PET, were normalized and hemispheric gray and white matter values were calculated. IVIM parametric values were compared with PET parameters and with clinically assessed disease severity.
Results
There was significant correlation between D* and MTT (r = –0.74, P < 0.001) and between f・D* and CBF (r = 0.52, P = 0.02) in the cortical areas. The f values in the white matter were significantly higher in symptomatic MMD patients than in healthy controls (P = 0.01).
Conclusion
IVIM may be used to non-invasively investigate cerebral hemodynamic impairment in patients with MMD. Further evaluation is needed to establish IVIM usage in clinical settings.
Keywords :
Moyamoya disease , diffusion magnetic resonance imaging , intravoxel incoherent motion imaging , ischemia , cerebral blood flow , positron emission tomography