Received: 23 November 2019
Accepted: 17 March 2020
First Online: 4 May 2020
Ethics approval and consent to participate
: It was a retrospective study with research ethics board approval. This study was approved by the Iwate Medical University and a waiver of consent was obtained (MH2019–059).
: This was a retrospective study; all patients underwent clinically indicated transarterial embolization. Informed consent was waived by the local ethics committee. All figures used in preparing the manuscript contain no individual or identifiable personal data.
: The authors declare that they have no competing interests.