Radially expandable cannula systems and methods for use

Inventors

Atto, Zaid • Cicek, Seray • Dilbert, Chevis

Abstract

A radially expandable trocar, port or cannula system is provided for use in minimally invasive surgeries. The cannula creates a port access with an initial small internal diameter. The passage of the cannula devices is defined by a plurality of elongate rigid members. A number of mechanisms are provided for expanding the passage of the cannula devices, by moving the plurality of elongate rigid members towards a larger radial location, thereby creating a larger internal diameter for the port. The elongate rigid members can be prevented from unintended movement when the system is at the un-expanded state, during expansion and when it is expanded to the desired larger diameter. Exemplary embodiments include methods of preventing gas loss from the tissue that would occur through the gaps created during expansion.

Core Innovation

The patent describes a cannula device for minimally invasive surgery in which a first housing and a second housing define axially aligned throughbores along a central axis. A plurality of elongate rigid members extend distally from the first and second housings and cooperatively define an axially aligned passage between proximal ends and distal tips, while the second housing is moveable in an axial direction along the central axis with respect to the first housing without being rotatable relative to one another.

The core mechanism increases the size of the passage by translating the second housing relative to the first housing so that the elongate rigid members move radially outwardly and diagonally with respect to the central axis. In particular, proximal ends of the elongate rigid members and the first housing comprise first tracks that include inter-engaging first tongues and first guides oriented diagonally relative to the central axis, and the second housing and the elongate rigid members comprise second tracks including second tongues and second guides.

In a related method, distal tips of the elongate rigid members are inserted through tissue into the subject's body, the cannula is expanded by moving the second housing relative to the first without relative rotation, and one or more instruments are introduced through the expanded passage to perform a medical procedure. The method may also include using an obturator to penetrate tissue and form an entry hole, with the obturator tip exposed before tissue penetration and removed prior to expansion.

Claims Coverage

The document provides two independent apparatus claims and one independent method claim. Across these independent claims, three inventive features are defined by the central-axis, non-rotational expansion using diagonal and radial track-and-tongue translation, and the sequence that inserts, expands, and introduces instruments through the passage.

Overall, the independent claims focus on a cannula device architecture with axially aligned first and second housings and a non-rotational axial expansion motion that uses diagonally oriented first guides and radially oriented second guides to drive radially outward and diagonal movement of a plurality of elongate rigid members, increasing the passage size. The independent method claim uses this expansion sequence and then introduces one or more instruments through the expanded passage.

Stated Advantages

Documented Applications