著者

Tomoyuki NOGUCHI Takashi YOSHIURA Akio HIWATASHI Osamu TOGAO Koji YAMASHITA Kouji KOBAYASHI Futoshi MIHARA Hiroshi HONDA

出版者

Japanese Society for Magnetic Resonance in Medicine

雑誌

Magnetic Resonance in Medical Sciences (ISSN:13473182)

巻号頁・発行日

vol.6, no.2, pp.91-97, 2007 (Released:2007-08-07)

参考文献数

19

被引用文献数

17 22

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Purpose: Pulsed arterial spin labeling (PASL) is a magnetic resonance (MR) method for measuring cerebral blood flow. Although several validation studies for PASL in animals and humans have been reported, no reports have detailed the fundamental study of PASL using a flow phantom. We compared the true and theoretical flow rates in a flow phantom to confirm the analytical validity of quantitative perfusion imaging with Q2TIPS sequence. Methods: We built a flow phantom consisting of a 40-mm diameter plastic syringe filled with plastic beads and small plastic tubes 4 mm in diameter. Gd-DTPA-doped 8L water solution (0.1 mM) was circulated between the syringe and a tank through a plastic tube by a constant flow pump while the flow rate was adjusted between 0 and 2.61 cm/s. Q2TIPS sequence parameters were TI1=50 ms and TI2=1400 ms. Five imaging slices of 50 subtraction images were acquired sequentially in a distal-to-proximal direction using a single-shot echo planar imaging (EPI) technique. The theoretical flow rate calculated based upon the previously reported kinetic model for Q2TIPS was compared with the true flow rate. Results: A good linear relationship was observed between the theoretical, F′, and true flow rates, F, in a flow rate range of 1.43 to 1.95 cm/s (F′=1.024•F−1.915, R2=0.902). The ratio of theoretical to true flow rate was 92 (+/−) 4%. Conclusion: Flow rate was quantified with reasonable accuracy when the entire amount of labeled bolus within the phantom could be recovered. Our experiment confirmed the analytical validity of Q2TIPS and suggested that blood flow measurement may be feasible using the Q2TIPS pulse sequence and kinetic model of the PASL equation.

著者

Yusuke Yakushiji Andreas Charidimou Tomoyuki Noguchi Masashi Nishihara Makoto Eriguchi Yusuke Nanri Atsushi Kawaguchi Tatsumi Hirotsu David J. Werring Hideo Hara

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

vol.57, no.2, pp.189-196, 2018-01-15 (Released:2018-01-15)

参考文献数

30

被引用文献数

18 28

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Objective We explored the association between the total small vessel disease (SVD) score obtained with magnetic resonance imaging and risk factors and outcomes in the Japanese population. Methods The presence of SVD features, including lacunes, cerebral microbleeds, white matter changes, and basal ganglia perivascular spaces on MRI, was summed to obtain a "total SVD score" (range 0-4). Ordinal and multinomial logistic regression analyses were performed to investigate the association of higher total SVD scores with vascular risk factors, the Mini-Mental State Examination (MMSE) score, and cerebral atrophy. Results We included 1,451 neurologically healthy adults (mean age, 57.1 years; 47% male). A multivariate ordinal logistic regression analysis showed that the total SVD score was associated with aging, hypertension, blood pressure (BP), diabetes mellitus, MMSE score, and deep cerebral atrophy, but the equal slopes assumption between scores did not hold. A multivariate multinomial logistic regression analysis (total SVD score 0=reference) showed that aging, hypertension, and BP were positively associated with scores of 1, 2, or ≥3. These effects, presented as odds ratios (ORs), increased as the score increased and were strongest with a score of ≥3 [aging (per 10-year increment), OR 4.00, 95% confidence interval (CI) 2.47-6.46; hypertension, OR 5.68, 95% CI 2.52-12.80; systolic BP (per standard deviation increase), OR 1.96, 95% CI 1.41-2.74, respectively]. Diabetes mellitus and deep cerebral atrophy tended to be associated with the SVD scores. The MMSE score showed no consistent associations. Conclusion The total SVD score may be a promising tool for indexing SVD, even in the Japanese population.