| 摘要 |
<p>An implantable drug pump (10) having a fluid storage reservoir (32) and an externally located syringe (20) for transferring fluid from the syringe (20) into the reservoir (32). More specifically, an implanted drum pump (10) includes a drug reservoir (32) and a volume (43), the reservoir (32) and volume (43) having a common wall defined by a flexible diaphragm (36). The volume (43) contains a liquid (42) having a vapor pressure at body temperature less than that of the ambient pressure surrounding the external syringe (20), thereby tending to provide a reservoir (32) pressure less than the ambient pressure. The syringe (20) includes a needle (22) having an orifice (24) located near its tip (26). The syringe (20) also includes a container (76) formed of a flexible material (78) which is in fluid communication with the orifice (24). An injection chamber (50) is in fluid communication with the reservoir (32). In operation, the needle (22) is forced through a pierceable septum (48) in the drug pump (10) so that the orifice (24) is in fluid communication with the reservoir (32). Because the ambient pressure surrounding the container (76) is greater than the pressure within the injection chamber (50) and the reservoir (32), fluid will flow from the container (76) into the reservoir (32) without any additional pressure being applied to the container (76). A unique valve responsive to the needle (22) piercing the septum (48) is also provided. Thus, a completely passive apparatus is disclosed in which a drug can be transferred from an external container into an implanted device only when a needle in fluid communication with the container is properly positioned with respect to the implanted device.</p> |
