Received: 29 September 2018
Accepted: 11 April 2019
First Online: 27 April 2019
Ethics approval and consent to participate
: The study was submitted to and approved by the Ethics Committee of Tohoku University Graduate School of Medicine (2010–253, 2017–1-005). Consent to participate was directly provided by patients or their families.
: The written consents for publication were obtained from patients, including two individuals for case reports, or their families.
: The authors declare that they have no competing interests.
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