Cryosurgical instrument and system and method of cryosurgery
US5674218A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1995 |
| Grant date | Oct 7, 1997 |
| Priority date | — |
| Expiry date | Feb 16, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2018/0268
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An improved cryosurgical system includes means for cooling the cryoprobe instrument to temperatures below the normal boiling point of liquid nitrogen as well as means for recovering the sub-cooled liquid coolant. A unique cryoprobe instrument of simplified construction uses an active vacuum for thermal insulation. Means are provided for controllably adjusting the length of the freezing zone of the cryoprobe to allow the freezing zone to be adjusted for different sizes and shapes of tumors which may be "observed" before surgery by ultrasound imaging. Multiple, disposable cryoprobe instruments can be individually controlled for both operating temperature and freeze zone length. A preferred refrigeration system for sub-cooling liquid nitrogen refrigerant or other cryogenic liquid refrigerant is based on the principles of evaporative cooling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.