stereoscopic ru00f6ntgenverfolgung moving objects in the context of the radiotherapy and radiochirurgie

摘要

A non-diagnostic, stereoscopic x-ray tracking method uses two x-ray tubes (1, 2) to alternately and repeatedly record x-ray images of an object (O[1]-O[3]) along two different viewing lines (X[1,1], X[1,2], X[1,3], X[2,1'], X[2,2'], X[2,3']). An extrapolated object trajectory is ascertained by determining surfaces and intersecting points. The minimum traverse from the object trajectory onto a current viewing line is ascertained and the three-dimensional position of the tracked object is approximated at the point at which the object trajectory meets the viewing line. The non-diagnostic, stereoscopic x-ray tracking method involves using two x-ray devices to repeatedly record x-ray images of an object along two different point of views through a target area of an irradiating apparatus, the two different points of view intersecting at a known angle. The two x-ray devices are controlled such that each x-ray device alternately obtains an image of the object as the object moves through the target area, and with the assistance of a computer. The method includes determining a first surface that is spanned by a first viewing line from the first x-ray device to the object in an image recorded at an earlier point in time and a second viewing line from the first x-ray device to the object in an image recorded at a later point in time; determining a first intersecting point from a third viewing line from the second x-ray device to the object in an image recorded at a point in time between the earlier point in time and the later point in time, and the first spanned surface; determining a second surface, where the later point in time becomes a new earlier point in time, and where the second surface is spanned by the second viewing line from the first x-ray device to the object in an image recorded at the new earlier point in time and a fourth viewing line from the first x-ray device to the object in an image recorded at a new later point in time; and determining a second intersecting point from a fifth viewing line from the second x-ray device to the object in an image recorded at a point in time between the new earlier point in time and the new later point in time, and the second spanned surface. A spatial straight connecting line that connects the first and second intersecting points is calculated. A minimum transversal between the spatial straight connecting line and the fourth viewing line of the object at the new later point in time is calculated. A three-dimensional position of the tracked object is approximated from an intersecting point of the minimum transversal and the fourth line of site at the new later point in time. Independent claims are included for: (1) computer program embodied on a computer readable medium for non-diagnostic, stereoscopic x-ray tracking of moving objects in the context of radiotherapy and radiosurgery; and (2) stereoscopic x-ray tracking device for tracking moving objects in the context of radiotherapy and radiosurgery.