Implant delivery assembly with expandable coupling/decoupling mechanism

Abstract

An occlusive implant delivery assembly includes a rapid response decoupling or detachment mechanism that does not effect significant migration of the implant during release. The assembly includes an occlusive implant device, such as an embolic coil, a pusher or device to carry the implant to the selected location, and an expandable coupling-decoupling mechanism for releasing the implant at the selected site. The mechanical construction provides rapid release times. In addition, the releasing mechanism generally operates without exerting any significant force on the implant, thereby avoiding any significant displacement of the implant during release.

Description

RELATED PATENT APPLICATION [0001] This application is a continuation of U.S. Ser. No. 08 / 363,264, filed Dec. 22, 1994, the entirety of which is hereby incorporated by reference.FIELD OF THE INVENTION [0002] The present invention generally relates to surgical instruments. More particularly, the invention relates to delivery assemblies for delivering an occlusive device, such as an embolic coil, to a selected site within a mammal using an expandable coupling or decoupling mechanism. BACKGROUND OF THE INVENTION [0003] The endovascular treatment of a variety of vascular maladies throughout the body is an increasingly more important form of therapy. Catheters have been used to place various treatment materials, devices, and drugs within arteries and veins in the human body. Examples of these devices and their use in such treatments are shown in U.S. Pat. Nos. 5,234,437 and 5,261,916, in which methods and devices for delivery of coils or wires within the human body to sites, such as aneur...

AI Technical Summary

Benefits of technology

The present invention provides a mechanical occlusive implant delivery assembly with a rapid response detachment mechanism that does not effect significant migration of the implant during release. The assembly includes an occlusive implant, a pusher, and an inflatable member. The inflatable member is expanded to release the implant at the selected site by simply unloading a locking force, which is applied uniformly to the inner surface of the coupling. The inflatable member and coupling are designed so that any force in the radial direction is countered by an equal and opposite force, thereby avoiding implant displacement during release. The inflatable member and tubular portion are also configured so that the hydraulic pressure generated by the inflatable member is applied uniformly to the inner surface of the tubular portion. The invention advantageously eliminates the need for auxiliary hydraulics and provides a simple and effective decoupling mechanism for the implant delivery assembly.

Problems solved by technology

However, there are concerns when discharging the coil from the distal end of the catheter.

Inaccurate placement of the coil can be problematic because once the coil has left the catheter, it is difficult to reposition or retrieve the coil.

The only perceived disadvantage of this method is that the electrolytic release of the coil may require a period of time that may inhibit rapid detachment of the coil from the pusher.

Among the drawbacks of this system is that it involves generally complicated laser optic componentry.

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