Takahiro Ikoma, Toshimitsu Kato, Kenya Okada, Noriaki Takama, Hideki Ishii, Takao Kimura, and Yoshito Tsushima declare that they have no conflicts of interest.

All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1964 and later versions. Informed consent was obtained from the patient.