Implantable, calibrateable measuring instrument for a body substance and a calibrating method
US4759371A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 1987 |
| Grant date | Jul 26, 1988 |
| Priority date | — |
| Expiry date | May 1, 2007 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/686
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An implantable measuring instrument for a body substance for use in controlling an implantable infusion device has a housing with a recess covered by a semi-permeable membrane which permits transfer of molecules of a selected size therethrough. The volume defined by the recess and the membrane is in communication with an expandable chamber in the housing and a channel leading directly or indirectly via an additional membrane to a sensor for the body substances to interest. The channel is also in communication with a pump. There is also provided another recess covered by a pierceable, resealable septum. A conduit leads from the septum to the sensor. For calibrating the instrument, a cannula is introduced through the septum, and all of the fluid in the conduit leading to the sensor is withdrawn by suction. A known calibrating substance is then introduced by the cannula through the septum until the conduit leading to the sensor is filled. Data can then be acquired from the sensor, and if necessary one or more operating parameters of the instrument can be re-set. This procedure can also be used for rinsing and/or reactivating the sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.