Radially expandable cannula devices, and systems and methods for using them

Inventors

Atto, Zaid • Manget, Amanda

Abstract

Cannula devices, systems, and methods are provided for introducing one or more instruments into a patient's body to perform a procedure. In one example, the cannula device includes first and second housings defining a throughbore, and a plurality of elongate members extending distally from the housings, the elongate members cooperatively defining a passage axially aligned with the throughbore between proximal ends and distal tips of the elongate members. The first housing is moveable in an axial direction with respect to the second housing to cause the proximal ends of the elongate members to move outwardly to increase a size of the passage and, optionally, may taper when expanded. Optionally, one or more secondary devices, e.g., an obturator with a sharpened tip, or an obturator and tubular access device may be provided that may be inserted through the throughbore into the passage before expansion of the passage.

Core Innovation

A cannula device includes a first housing and a second housing defining first and second throughbores aligned along a central axis. The second housing is moveable in an axial direction along the central axis with respect to the first housing, and a plurality of elongate members cooperatively define a passage axially aligned with the first throughbore between proximal ends and distal tips of the elongate members.

Guide elements are provided on the proximal ends of the elongate members and on the first and second housings. The guide elements cooperate such that axial movement of the first housing with respect to the second housing along the central axis causes the proximal ends of the elongate members to move outwardly with respect to the central axis and away from each other, thereby increasing a size of the passage.

When the distal tips are constrained, the elongate members are configured to define a tapered shape extending from the proximal ends towards the distal tips. The system further includes introducing one or more instruments into a patient's body to perform a procedure by using the cannula device and a secondary device or obturator inserted through the throughbore into the passage.

The distal tapers of the elongate members provide an outlet having a larger diameter than the passage, and the secondary device or obturator engages the first housing to cause distal relative motion of the housings that moves the elongate members away from each other to increase the passage size. Embodiments also include obturator tips sized to receive a portion of the obturator tip and, optionally, sealing and valve arrangements to control gas loss.

Claims Coverage

The document provides three independent claims that share a common expandable cannula mechanism with multiple elongate members driven by axial relative motion of two coaxial housings through cooperating guide elements. Across the independent claims, additional inventive feature sets are expressed for tapered outlet behavior and for coupling expansion to an obturator or secondary device, optionally including sealing and valve related features.

Across the independent claims, the shared inventive core is the axial, guide-element-driven outward movement of proximal ends of elongate members to increase an axially aligned passage size, including formation of a tapered shape when distal tips are constrained. The independent system claims additionally specify how obturator or secondary devices inserted through the throughbore engage the cannula or are received by distal tapers to produce an outlet larger than the passage and to drive expansion by relative distal motion of the housings.

Stated Advantages

Documented Applications