PROBLEM TO BE SOLVED: To provide a tomosynthesis imaging apparatus capable of avoiding the concentration of load on one radiation tube when pre-imaging to set the condition of radiation projection for tomosynthesis imaging is performed with a radiation source comprised of a plurality of radiation tubes, and also to provide a method of operating the tomosynthesis imaging apparatus.SOLUTION: A radiation source of a mammography apparatus is comprised of a plurality of first radiation tubes and one second radiation tube. The first radiation tubes are used for tomosynthesis imaging. In contrast, the second radiation tube is used for pre-imaging which is performed before the tomosynthesis imaging to set the condition of radiation projection for the tomosynthesis imaging. The first radiation tubes are disposed at a plurality of positions such that the focal points of the radiations are arranged linearly or arc-wise with equal intervals. The second radiation tube is disposed at a position offset backward on a side opposite to a side projected with the radiations, with respect to the plurality of positions at which the first radiation tubes are disposed.SELECTED DRAWING: Figure 9COPYRIGHT: (C)2020,JPO&INPIT【課題】放射線源を複数の放射線管で構成して、トモシンセシス撮影の放射線の照射条件を設定するためのプレ撮影を行う場合に、１つの放射線管への負荷の集中を避けることが可能なトモシンセシス撮影装置とその作動方法を提供する。【解決手段】乳房撮影装置の放射線源は、複数の第１放射線管、および１つの第２放射線管で構成される。第１放射線管はトモシンセシス撮影に用いられる。一方、第２放射線管は、トモシンセシス撮影に先立ち行われる、トモシンセシス撮影の放射線の照射条件を設定するためのプレ撮影に用いられる。第１放射線管は、放射線の焦点が、直線状または円弧状に、等しい間隔で並ぶ設定とされた複数の位置に配される。第２放射線管は、第１放射線管が配される複数の位置に対して、放射線を照射する側とは反対側の、後方にオフセットした位置に配される。【選択図】図９
