# US 10,369,328 B2 · Adjustable stiffness catheter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,369,328 B2 - Document ID: US10369328B2 - Status: Granted - Kind: B2 - Application number: 14/184,427 - Filed: 2014-02-19 - Published: 2014-08-21 - Granted: 2019-08-06 - Earliest claimed: 2013-02-19 - Assignees: Beth Israel Deaconess Medical Center, Inc. - Applicants: Leo Lee Tsai; Yuyin Chen; Vyas Ramanan - Inventors: Leo Lee Tsai; Yuyin Chen; Vyas Ramanan - Web page: https://patentgrep.com/patent/US10369328B2 ## CPC - A61B 1/005: Flexible endoscopes - A61B 1/00071: {Insertion part of the endoscope body (A61B1/0055 takes precedence)} - A61B 1/0055: {Constructional details of insertion parts, e.g. vertebral elements} - A61M 25/0009: {Making of catheters or other medical or surgical tubes} - A61M 25/0013: {Weakening parts of a catheter tubing, e.g. by making cuts in the tube or reducing thickness of a layer at one point to adjust the flexibility} - A61M 25/0043: {characterised by structural features} - A61M 25/0054: {with regions for increasing flexibility} - A61M 25/0108: {using radio-opaque or ultrasound markers} - A61M 25/0136: {Handles therefor} - A61M 25/0138: {having flexible regions as a result of weakened outer material, e.g. slots, slits, cuts, joints or coils} - A61M 25/0147: {with movable mechanical means, e.g. pull wires} - A61M 25/09: Guide wires - A61B 17/1214: {Coils or wires} - A61B 17/12186: {liquid materials adapted to be injected} - A61B 2017/00305: {Constructional details of the flexible means} - A61B 2017/1205: {Introduction devices} - A61F 2/95: Instruments specially adapted for placement or removal of stents or stent-grafts - A61F 2/958: Inflatable balloons for placing stents or stent-grafts - A61M 2025/0004: {having two or more concentrically arranged tubes for forming a concentric catheter system} - A61M 2025/0062: {having features to improve the sliding of one part within another by using lubricants or surfaces with low friction} - A61M 2025/0063: {having means, e.g. stylets, mandrils, rods or wires to reinforce or adjust temporarily the stiffness, column strength or pushability of catheters which are already inserted into the human body} - Y10T 156/1062: Prior to assembly - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The present invention relates to a catheter that has adjustable stiffness that enables a user to select the stiffness of at least one region of the catheter during insertion and navigation through a body lumen. A preferred embodiment of the invention works in combination with a guidewire to enable placement of the catheter at a position within the vascular system, for example, to enable treatment of a variety of medical conditions. The catheter can include segments that undergo relative movement in response to actuation by the user to adjust the flexibility of the at least one region, preferably located at or near the distal end of the catheter. ## Claims ### Claim 1 An adjustable stiffness catheter comprising: an inner tube having a first plurality of spaced regions comprising a first material having a first stiffness separated by a first plurality of spaced segments comprising a second material having a greater stiffness than the first plurality of spaced regions; an outer tube extending around the inner tube, the outer tube having a second plurality of spaced regions having a second stiffness separated by a second plurality of tubular spaced segments having a greater stiffness than the second plurality of spaced regions; and an actuator configured to provide relative longitudinal translation of the inner tube and the outer tube such that a radial stiffness of at least a distal portion of the catheter is altered from a first stiffness level to a different second stiffness level. ### Claim 2 (depends on 1) The catheter of claim 1, wherein the first plurality of spaced segments comprise tubular elements that are spaced apart by the first plurality of spaced regions. ### Claim 3 (depends on 1) The catheter of claim 1, further comprising a liner positioned between the inner tube and the outer tube. ### Claim 4 (depends on 3) The catheter of claim 3, wherein the liner comprises a flexible region over the inner tube, the inner tube having alternating segments of higher stiffness and lower stiffness. ### Claim 5 (depends on 1) The catheter of claim 1, further comprising a handle mounted at a proximal end of the catheter, the handle including a portion of the actuator. ### Claim 6 (depends on 5) The catheter of claim 5, wherein the handle comprises at least one fluid supply port. ### Claim 7 (depends on 5) The catheter of claim 5, wherein the handle comprises two fluid supply ports. ### Claim 8 (depends on 1) The catheter of claim 1, wherein the actuator comprises a cam and a cam follower operably attached to one of the inner tube and outer tube. ### Claim 9 (depends on 1) The catheter of claim 1, further comprising at least one lumen extending through the catheter. ### Claim 10 (depends on 9) The catheter of claim 9, further comprising a fluid source coupled to the at least one lumen for delivering a fluid through the at least one lumen. ### Claim 11 (depends on 1) The catheter of claim 1, further comprising a guidewire positioned within a lumen within the inner tube. ### Claim 12 (depends on 1) The catheter of claim 1, wherein the first plurality of spaced regions comprise a polymeric material. ### Claim 13 (depends on 1) The catheter of claim 1, further comprising a lubricious coating disposed on a surface of at least one of the inner tube and the outer tube. ### Claim 14 (depends on 13) The catheter of claim 13, wherein the lubricious coating is disposed on an outer surface of the inner tube. ### Claim 15 (depends on 13) The catheter of claim 13, wherein the lubricious coating is disposed on an outer surface of the inner tube and a second lubricious coating is disposed on an outer surface of the outer tube. ### Claim 16 (depends on 13) The catheter of claim 13, wherein the lubricious coating comprises polytetrafluoroethylene. ### Claim 17 (depends on 13) The catheter of claim 13, wherein the lubricious coating comprises hydrophilic polymer. ### Claim 18 (depends on 1) The catheter of claim 1, wherein the first plurality of spaced regions are disposed at a distal end of the catheter such that the distal end has a minimum radius of curvature in a range of 2-6 mm, or alternatively, in a range of 3-5 mm. ### Claim 19 (depends on 1) The catheter of claim 1, wherein the second plurality of spaced regions are disposed at a distal end of the catheter, the catheter having a diameter for insertion into a neurovascular lumen. ### Claim 20 (depends on 1) The catheter of claim 1, further comprising at least one radiopaque marker. ### Claim 21 (depends on 1) The catheter of claim 1, wherein the actuator is operably coupled to the inner tube to move the inner tube longitudinally within the outer tube. ### Claim 22 (depends on 1) The catheter of claim 1, further comprising a treatment device for delivery to a treatment site. ### Claim 23 (depends on 1) The catheter of claim 1, further comprising a medicament delivery channel. ### Claim 24 (depends on 1) The catheter of claim 1 wherein the first stiffness level comprises a position of the first plurality of spaced regions that are registered with the second plurality of spaced segments. ### Claim 25 (depends on 1) The catheter of claim 1 wherein the second stiffness level comprises a position of the first plurality of spaced regions that are registered with the second plurality of spaced regions. ### Claim 26 (depends on 1) The catheter of claim 1 wherein the first plurality of spaced regions have different lengths, or different materials, or different durometer ratings, or combinations thereof. ### Claim 27 (depends on 1) The catheter of claim 1 wherein a section of the catheter has a continuum of selectable stiffness levels. ### Claim 28 (depends on 1) The catheter of claim 1 wherein a distal portion of the catheter having the first stiffness level has a first radius of curvature. ### Claim 29 (depends on 1) The catheter of claim 1 wherein a distal portion of the catheter having the second stiffness level has a second radius of curvature. ### Claim 30 (depends on 1) The catheter of claim 1 wherein the catheter comprises a vascular catheter. ### Claim 31 (depends on 9) The catheter of claim 9 wherein the at least one lumen of the inner tube is sized to receive a drainage tube. ### Claim 32 (depends on 1) The catheter of claim 1 further comprising a tubular liner between the inner tube and the outer tube. ### Claim 33 An adjustable stiffness catheter comprising: an inner tube at a distal portion of the catheter having a first plurality of spaced regions comprising a first material having a first stiffness, each first spaced region being separated by a first corresponding plurality of spaced segments comprising a second material having a greater stiffness than the plurality of spaced regions; an outer tube at the distal portion of the catheter extending around the inner tube, the outer tube having a second plurality of spaced regions having a second stiffness, each second spaced region being separated by a second corresponding plurality of tubular spaced segments having a greater stiffness than the second plurality of spaced regions; a layer extending continuously at the distal portion of the catheter between the inner tube and the outer tube that lubricates relative translation between the inner tube and the outer tube; and an actuator configured to provide relative longitudinal translation of the inner tube and the outer tube at least at a distal portion of the catheter such that the first plurality of spaced regions and the second plurality of spaced segments undergo relative movement to alter a stiffness of the catheter from a first stiffness level to a different second stiffness level. ### Claim 34 (depends on 33) The catheter of claim 33 wherein the layer comprises a tubular liner. ### Claim 35 (depends on 33) The catheter of claim 33 wherein the layer comprises a coating on the inner tube or on the outer tube. ### Claim 36 (depends on 33) The catheter of claim 33 wherein the layer comprises a polymer material. ### Claim 37 An adjustable stiffness neurovascular catheter comprising: an inner tube having a first plurality of spaced regions having a first stiffness separated by a first plurality of spaced segments having a greater stiffness than the first plurality of spaced regions, the first plurality of spaced segments and the first plurality of spaced regions each comprises one or more polymeric materials; an outer tube having a diameter in a range of 1.5-4 Fr extending around the inner tube such that the outer tube and the inner tube are configured to undergo relative longitudinal translation, the outer tube having a second plurality of spaced regions having a second stiffness separated by a second plurality of spaced segments having a greater stiffness than the second plurality of spaced regions, the outer tube having an inner tubular surface that is concentric around the inner tube; and an actuator configured to provide relative longitudinal translation of the inner tube and the outer tube such that a stiffness of the catheter is altered from a first stiffness level to a different second stiffness level. ### Claim 38 (depends on 37) The catheter of claim 37, wherein the first plurality of spaced segments comprise a different material than the first plurality of spaced regions and includes tubular elements that are spaced apart by the first plurality of spaced regions. ### Claim 39 (depends on 38) The catheter of claim 38, further comprising a continuous layer positioned between the inner tube and the outer tube. ### Claim 40 (depends on 38) The catheter of claim 38, further comprising a handle mounted at a proximal end of the catheter, the handle including a portion of the actuator. ### Claim 41 (depends on 40) The catheter of claim 40, wherein the handle comprises at least one fluid supply port. ### Claim 42 (depends on 40) The catheter of claim 40, wherein the handle comprises two fluid supply ports. ### Claim 43 (depends on 38) The catheter of claim 38, wherein the actuator comprises a cam and a cam follower operably attached to one of the inner tube and outer tube. ### Claim 44 (depends on 38) The catheter of claim 38, further comprising at least one lumen extending through the catheter. ### Claim 45 (depends on 44) The catheter of claim 44, further comprising a fluid source coupled to the at least one lumen for delivering a fluid through the at least one lumen. ### Claim 46 (depends on 38) The catheter of claim 38, further comprising a guidewire positioned within a lumen within the inner tube. ### Claim 47 (depends on 38) The catheter of claim 38, further comprising a lubricious coating disposed on a surface of at least one of the inner tube and the outer tube.