医学部

Yoshiyuki Ozawa

  (小澤 良之)

Profile Information

Affiliation
Professor, Department of Diagnostic Radiology, School of Medicine, Fujita Health University
Degree
名古屋市立大学大学院大学院医学研究科生体防御・総合医学 博士課程/生体防御・総合医学 博士(医学)

J-GLOBAL ID
201001035788507710
researchmap Member ID
6000021563

Research Areas

 1

Papers

 84
  • Yoshiharu Ohno, Takahiro Ueda, Masahiko Nomura, Yuichiro Sano, Kaori Yamamoto, Maiko Shinohara, Masato Ikedo, Masao Yui, Akiyoshi Iwase, Hiroyuki Nagata, Takeshi Yoshikawa, Daisuke Takenaka, Akihiro Tomita, Nobuyuki Fujita, Yoshiyuki Ozawa
    Magnetic resonance imaging, 110240-110240, Sep 29, 2024  
    PURPOSE: The purpose of this study was to determine the capability of proton density with fat fraction (PD-FFQ) imaging to help assess hematopoietic ability and diagnose aplastic anemia in adults. METHODS: Between January 2021 and March 2023, patients diagnosed with aplastic anemia (AA: n = 14) or myelodysplastic syndrome (MDS: n = 14) were examined by whole-body PD-FFQ imaging, and 14 of 126 age and gender matched patients who had undergone the same PD-FFQ imaging were selected as control group. All proton density fat fraction (PDFF) index evaluations were then performed by using regions of interest (ROIs). Pearson's correlation was used to determine the relationship between blood test results and each quantitative index, and ROC-based positive test and discrimination analyses to compare capability to differentiate the AA from the non-AA group. Finally, sensitivity, specificity and accuracy of all quantitative indexes were compared by means of McNemar's test. RESULTS: Mean PDFF, standard deviation (SD) and percentage of coefficient of variation (%CV) for vertebrae showed significant correlation with blood test results (-0.52 ≤ r ≤ -0.34, p < 0.05). Specificity (SP) and accuracy (AC) of %CV of PDFF in vertebrae were significantly higher than those of mean PDFF in vertebrae and the posterior superior iliac spine (SP: p = 0.0002, AC: p = 0.0001) and SD of PDFF in vertebrae (SP: p = 0.008, AC: p = 0.008). Moreover, AC of SD of PDFF in vertebrae was significantly higher than that of mean PDFF in vertebrae and the posterior superior iliac spine (p = 0.03). CONCLUSION: Whole-body PD-FFQ imaging is useful for hematopoietic ability assessment and diagnosis of aplastic anemia in adults.
  • Tomoki Takahashi, Yoshiyuki Ozawa, Hidekazu Hattori, Masahiko Nomura, Takahiro Ueda, Tomoya Horiguchi, Kazuyoshi Imaizumi, Yasushi Matsuda, Yasushi Hoshikawa, Yuka Kondo-Kawabe, Tetsuya Tsukamoto, Hiroyuki Nagata, Yoshiharu Ohno
    Journal of thoracic imaging, Sep 16, 2024  
  • Takahiro Ueda, Kaori Yamamoto, Natsuka Yazawa, Ikki Tozawa, Masato Ikedo, Masao Yui, Hiroyuki Nagata, Masahiko Nomura, Yoshiyuki Ozawa, Yoshiharu Ohno
    European radiology experimental, 8(1) 103-103, Sep 10, 2024  
    BACKGROUND: We aimed to determine the capabilities of compressed sensing (CS) and deep learning reconstruction (DLR) with those of conventional parallel imaging (PI) for improving image quality while reducing examination time on female pelvic 1.5-T magnetic resonance imaging (MRI). METHODS: Fifty-two consecutive female patients with various pelvic diseases underwent MRI with T1- and T2-weighted sequences using CS and PI. All CS data was reconstructed with and without DLR. Signal-to-noise ratio (SNR) of muscle and contrast-to-noise ratio (CNR) between fat tissue and iliac muscle on T1-weighted images (T1WI) and between myometrium and straight muscle on T2-weighted images (T2WI) were determined through region-of-interest measurements. Overall image quality (OIQ) and diagnostic confidence level (DCL) were evaluated on 5-point scales. SNRs and CNRs were compared using Tukey's test, and qualitative indexes using the Wilcoxon signed-rank test. RESULTS: SNRs of T1WI and T2WI obtained using CS with DLR were higher than those using CS without DLR or conventional PI (p < 0.010). CNRs of T1WI and T2WI obtained using CS with DLR were higher than those using CS without DLR or conventional PI (p < 0.003). OIQ of T1WI and T2WI obtained using CS with DLR were higher than that using CS without DLR or conventional PI (p < 0.001). DCL of T2WI obtained using CS with DLR was higher than that using conventional PI or CS without DLR (p < 0.001). CONCLUSION: CS with DLR provided better image quality and shorter examination time than those obtainable with PI for female pelvic 1.5-T MRI. RELEVANCE STATEMENT: CS with DLR can be considered effective for attaining better image quality and shorter examination time for female pelvic MRI at 1.5 T compared with those obtainable with PI. KEY POINTS: Patients underwent MRI with T1- and T2-weighted sequences using CS and PI. All CS data was reconstructed with and without DLR. CS with DLR allowed for examination times significantly shorter than those of PI and provided significantly higher signal- and CNRs, as well as OIQ.
  • Kohei Fujita, Yoshihiro Kanemitsu, Hirotsugu Ohkubo, Akihito Okada, Akiko Nakano, Keima Ito, Yuta Mori, Kensuke Fukumitsu, Satoshi Fukuda, Takehiro Uemura, Tomoko Tajiri, Yutaka Ito, Tetsuya Oguri, Yoshiyuki Ozawa, Takayuki Murase, Akio Niimi
    ERJ open research, 10(5), Sep, 2024  
    The high frequency of productive cough in idiopathic pulmonary fibrosis (IPF) impacts quality of life. Reduced normal lung volume is linked to cough severity, predicting poorer outcomes. Insights could enhance IPF management and patient wellbeing. https://bit.ly/4bPOCzC.
  • Kohei Fujita, Akihito Okada, Hirotsugu Ohkubo, Akiko Nakano, Keima Ito, Yuta Mori, Kensuke Fukumitsu, Satoshi Fukuda, Yoshihiro Kanemitsu, Takehiro Uemura, Tomoko Tajiri, Yutaka Ito, Tetsuya Oguri, Yoshiyuki Ozawa, Takayuki Murase, Akio Niimi
    Respiratory investigation, 62(5) 889-896, Aug 7, 2024  
    BACKGROUND: Patients with idiopathic pulmonary fibrosis (IPF) often experience sarcopenia and malnutrition. However, this has not been fully examined through longitudinal surveys. This study investigated whether sarcopenia and malnutrition were associated with 1-year outcomes in IPF. METHODS: We evaluated sarcopenia and nutritional status in 64 outpatients with IPF. We assessed the time-to-event for respiratory-related hospitalizations or deaths 12 months after enrollment. Sarcopenia was diagnosed by the criteria of the Asian Working Group for Sarcopenia, 2019. Nutritional status was assessed by serum transthyretin and the Geriatric Nutritional Risk Index (GNRI). RESULTS: The average age was 73.6 ± 7.9 years, and the percent predicted forced vital capacity (FVC) was 81.9 ± 15.7%. Of the 64 patients, 24 (37.5%) had sarcopenia. The median serum transthyretin level and mean GNRI were 23.8 mg/dL and 102, respectively. Eleven patients (17.2%) experienced respiratory-related hospitalization or death within the first year. Cox regression analysis showed that the % predicted diffusion capacity for carbon monoxide, lowest oxygen saturation in the 6-min walk test, serum transthyretin level, and GNRI were significant predictors of 1-year outcomes. The Kaplan-Meier method, which divided the patients into two groups based on a transthyretin level of 22.6 mg/dL, showed a significant difference (P < 0.001, log-rank test). Sarcopenia and the percent predicted FVC did not predict the 1-year outcomes. CONCLUSIONS: This pilot study represents the first longitudinal survey assessing patients with IPF for sarcopenia and malnutrition. Serum transthyretin levels may predict respiratory-related hospitalization or death within 1 year in patients with IPF.

Misc.

 105

Presentations

 12

Research Projects

 9