Open configuration MRI magnetic flux path
US5864236A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 5, 1996 |
| Grant date | Jan 26, 1999 |
| Priority date | — |
| Expiry date | Jul 5, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/3806
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved MRI magnet structure is created by utilizing a lower pole mounting support with one or more vertically extending yokes. The one or more vertically extending yokes mount an upper pole mounting structure including an upper pole mounting ring and at least one spoke connecting the ring to at least one of the vertically extending structural supports. The average effective spacing of the upper pole mounting structure is greater than the air gap between the upper and lower pole thereby resulting in improved uniformity of the B.sub.o field at the patient imaging volume. In a preferred embodiment, a pie-shaped cryostat encompasses a plurality of radially distributed superconducting electromagnets for generating a more uniform field in the patient imaging volume. The patient imaging field uniformity in some embodiments can be improved by the use of shim coils and/or shim rings associated with either the upper or lower poles to further modify the field within the patient imaging volume.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.