04994047 is referenced by 203 patents and cites 11 patents.

A swellable cannula is formed of concentric inner and outer hydrophilic and substantially non-hydrophilic layer structures. The hydrophilic layer structure comprises at least 2/3rds of the cross-sectional area of the wall of the cannula. The substantially non-hydrophilic layer structure is either substantially water impermeable or allows water to pass through at a controlled rate. The substantially non-hydrophilic layer structure may also control the diffusion of medicaments. The cannula has controlled softenability and swellability characteristics.

Title
Multi-layer cannula structure
Application Number
7/191007
Publication Number
4994047
Application Date
May 6, 1988
Publication Date
February 19, 1991
Inventor
Joseph R Thomas
Fremont
CA, US
Jack M Walker
Portola Valley
CA, US
Agent
Fleisler Dubb Meyer & Lovejoy
Assignee
Menlo Care
CA, US
IPC
A61M 5/00
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