Use of shape memory alloy for internally fixing light emitting device at treatment site
US6080160A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1996 |
| Grant date | Jun 27, 2000 |
| Priority date | — |
| Expiry date | Dec 4, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2090/306
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method and apparatus for selectively engaging and disengaging an anchor to fix a medical device at a selected site within a patient's body. A shape memory alloy (SMA) such as Nitinol is used to fabricate one or more anchors for the medical device. The shape memory effect exhibited by the SMA is thermally activated. One embodiment of the anchor has a substantially circular shape when at its martensite temperature and reverts to an elliptical shape at its austenite temperature. Another embodiment is a substantially straight strip at its martensite temperature and has an end that curls to engage tissue when at its austenite temperature. Still another embodiment includes a pair of anchors that extend outwardly from each side of an elongate probe at their austenite temperature and retract inwardly against the sides of the probe at their martensite temperature. The change in the shape of the SMA elements tends to anchor the medical device or probe at the treatment site. To change the temperature of the SMA elements, an electrical current is selectively energized to provide heat, or thermal conduction between the SMA and a heat source or a heat sink is employed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.