Arrangement for examining a body with ionizing radiation

US4124799A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventor

• Rudolf Schittenhelm · Erlangen, DE

Key dates

• Filing date: Feb 25, 1977
• Grant date: Nov 7, 1978
• Expiry date: Feb 25, 1997

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61B6/4035
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

In radiotherapy, for example, a computer-tomogram is to be formed with a conventional relatively low dosage but with sufficient information content to enable the working out of an irradiation plan with a specific selected isodose distribution. Since the normally measured attenuation coefficients are not valid with respect to substantially harder x-radiation or gamma radiation, the present disclosure teaches the introduction of test bodies into the spacial region to be scanned in generating the computer tomograph, such test bodies having the same percentage contents of the same elements as are present in the particular body volume to be examined and having a density which is adapted as far as possible to such body volume, the density however being graduated such that graduated attenuation coefficients are recorded for the test bodies in the resultant computer tomogram. Thus it is possible to find a test body section whose attenuation coefficient is identical with that of the body tissue to be subsequently subjected to radiation therapy. Since this test body section also quantitatively manifests the same elements, the attenuation coefficient of the test body agrees with that of the b…