A method is for examining a body region of an examination object, which body
region
performs a periodic movement in the form of a sequence of movement cycles including
phases of the periodic movement. The method preferably uses a CT apparatus with
a radiation source for generating a radiation that penetrates through the examination
object at different projection angles, and a detector system for the radiation
emerging from the radiation source. An image, at least of the body region that
performs the periodic movement, is determined by way of an electronic computing
device from the output data of the detector system, which correspond to the detected
radiation and are used as measurement data. In this case, it is provided that,
from a number n1 of preferably successive movement cycles, data intervals
are taken with respect to the same phase of the periodic movement. The overall
length of these intervals produces at least one reconstruction interval that suffices
for determining an image. The number of movement cycles from which the data intervals
of a reconstruction interval originate increases as the frequency of the periodic
movement increases, and the length of the data intervals falls as the frequency
of the periodic movement increases.