Method and apparatus for automatic exposure control in CT scanning

US6744846B2 · kind B2 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Stefan Popescu · Erlangen, DE
• Christoph Suess · Erlangen, DE
• Heiko Wolf · Thalwil, CH
• Dietmar Hentschel · Vacha, DE

Key dates

• Filing date: Sep 26, 2002
• Grant date: Jun 1, 2004
• Expiry date: Oct 28, 2022

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61B6/027
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

In a computed tomography apparatus and a method for automatic exposure control in computed tomography scanning, an exposure controller, during a first half of a revolution of an X-ray focus around a subject, calculates an actual attenuation profile of a slice of the subject from electrical signals generated by the radiation detector in the first half of the revolution, and calculates an extrapolated attenuation profile of the slice for a second half of the revolution from the actual attenuation profile, and adjusts an operating parameter of the X-ray source, such as the tube current, to modify the radiation dose emitted by the X-ray source during the second half of the revolution dependent on the extrapolated attenuation profile.