Simultaneous transmission and emission converging tomography
US5338936A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1993 |
| Grant date | Aug 16, 1994 |
| Priority date | — |
| Expiry date | Mar 8, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2211/432
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A SPECT system includes three gamma camera heads (22a), (22b), (22c) which are mounted to a gantry (20) for rotation about a subject (12). The subject is injected with a source of emission radiation, which emission radiation is received by the camera heads. Transmission radiation from a transmission radiation source (30) is truncated to pass through a central portion of the subject but not peripheral portions and is received by one of the camera heads (22a) concurrently with the emission data. As the heads and radiation source rotate, the transmitted radiation passes through different parts or none of the peripheral portions at different angular orientations. An ultrasonic range arranger (152) measures an actual periphery of the subject. Attenuation properties of the subject are determined by reconstructing (90") the transmission data using an iterative approximation technique and the measured actual subject periphery. The actual periphery is used in the reconstruction process to reduce artifacts attributable to radiation truncation and the associated incomplete sampling of the peripheral portions. An emission reconstruction processor (112) reconstructs the emission projection data…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.