A review of PET attenuation correction methods for PET-MR.

"Declarations Ethics approval and consent to participateNot applicable. Consent for publicationNot applicable. Competing interestsThe authors have no financial or proprietary interests in any material discussed in this article. Competing interests The authors have no financial or proprietary interests in any material discussed in this article."

"Funding This work was supported by the Wellcome/EPSRC Centre for Medical Engineering [WT 203148/A/16/Z]. King’s College London and UCL Comprehensive Cancer Imaging Centre is funded by the CRUK and EPSRC in association with the MRC and DoH (England). The research was supported by the National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health."