RT Journal Article SR Electronic T1 Radiation safety and knowledge: what do we know? JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 477 OP 477 DO 10.1136/rapm-2021-102574 VO 46 IS 6 A1 Alaa Abd-Elsayed YR 2021 UL http://rapm.bmj.com/content/46/6/477.abstract AB