Computer tomography unit and method for operating same

• US 20020067793A1
• Filed: 09/18/2001
• Published: 06/06/2002
• Est. Priority Date: 09/18/2000
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Stierstorfer, Karl
• Granted Patent: US 6,574,296 B2
• Time in Patent Office: Days
• US Class Current: 378/4
• CPC Class Codes: A61B 5/0035 adapted for acquisition of images from more than one imaging mode, e.g. combining MRI and optical tomography
• CPC Class Codes: A61B 5/0064 Body surface scanning
• CPC Class Codes: A61B 5/107 Measuring physical dimensions, e.g. size of the entire body or parts thereof
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/4417 related to combined acquisition of different diagnostic modalities
• CPC Class Codes: A61B 6/466 adapted to display 3D data
• CPC Class Codes: A61B 6/5235 combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT
• CPC Class Codes: A61B 6/5247 combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound

Abstract

In a computed tomography and a method for operating a computed tomography unit, in order to scan an object under investigation a radiation source emits a pyramid-shaped X-ray beam, which penetrates through the object under examination and strikes a radiation detector. The computer tomography unit has an optical recording device which, during the scanning, records optical images of a partial surface of the object, which faces the X-ray source and through which the pyramid-shaped X-ray beam has penetrated. An image of the surface of the object under examination is constructed from optical images obtained in this manner this image is assigned to a sectional image obtained by means of the scan, or to an overview image.

Claims

1. A computed tomography unit comprising:

a radiation source which emits a pyramid-shaped X-ray beam adapted to penetrate an examination subject;

a radiation detector on which said X-ray beam is incident after passing through said examination subject, said X-ray source and said radiation detector thereby scanning said examination subject with a portion of a surface of said examination subject, facing said X-ray source, having said pyramid shaped X-ray beam penetrate therethrough; and

an optical recording device which, during said scanning, records an optical image of said portion of said surface.

2. A computed tomography unit as claimed in claim 1 wherein said X-ray source and said radiation detector are disposed on a rotating gantry, and wherein said optical recording device is also disposed on said gantry.

3. A computed tomography unit as claimed in claim 1 wherein said optical recording device comprises at least one charge coupled device linear array.

4. A computed tomography unit as claimed in claim 1 wherein said optical recording device has an automatic focusing device.

5. A computed tomography unit as claimed in claim 1 further comprising a signal processing unit for processing said optical images.

6. A method for operating a computed tomography unit, comprising the steps of:

scanning an examination subject by emitting a pyramid-shaped X-ray beam, which penetrates the examination subject, and detecting X-rays from said X-ray beam after penetrating said subject with a radiation detector, said scan producing a scan image selected from the group consisting of a diagnostic image and an overview image, said scanning proceeding in a plurality of scanning steps;

recording an optical image of a portion of a surface of said examination subject penetrated by said X-ray beam for each scanning step;

constructing an image of a surface of said subject from a plurality of said optical images; and

assigning said image of said surface to a slice image obtained from said scanning.

7. A method as claimed in claim 6 comprising constructing said image of said surface of said subject in a signal processing unit.