| 摘要 |
<p>An emission computed tomograph in which a radiation detector (11) is rotated around a subject to detect radiation emitted from radioisotopes distributed in the subject and in which a distributing image of the radioisotopes in any section of the subject is reconstructed on the basis of the detected data, the tomograph including detector-driving apparatus (12) for amoving the detector to or from the subject as the detector is rotated around the subject, at least one distance-measuring device, such as an ultrasonic transducer (14), for measuring the distance between the detector and subject at every rotational position of the detector, and apparatus (16, 17, 18, 19) responsive to the measured distance for controlling the detector-driving apparatus in order to adjust the distance between the detector and subject within a predetermined range.</p> |
