Transformable catheter and method

Claim 2

A transformable catheter comprising: a sheath having a straight relaxed shape and having a diameter sufficiently small so that the sheath may be inserted into the human body, said sheath having a length which is a substantial fraction of the entire length of the transformable catheter, and having a bore therethrough running substantially from the proximal end of the sheath to the distal end of the sheath; a preformed inner catheter having a complex curve formed into the distal end thereof, said preformed catheter being sized to fit in the sheath bore and being axially movable with respect to the sheath in the bore, said sheath being sufficiently rigid and the inner catheter being sufficiently pliable so that withdrawal of the inner catheter into the sheath substantially irons out the curve of that portion of the distal tip which is disposed in the sheath, said distal tip resuming its complex curve shape upon movement thereof completely out of the sheath bore, said inner catheter having a length substantially corresponding to the length of the transformable catheter, said complex curve having at least three curve portions having different radii of curvature, at least one of said curve portions having a direction of curvature retrograde to that of at least two of the other curve portions; at least one wire running from the proximal end of the sheath to the vicinity of the distal end of the sheath, said wire being connected to the sheath adjacent the distal end so as to allow the distal tip of the sheath to be deflected from the straight relaxed shape upon movement of said wire; whereby by suitable manipulation of the wire and of the inner catheter with respect to the sheath the shape of the exposed portion of the distal end of the inner catheter may be reformed and transformed to any of a variety of shapes as desired by the user.

Claim 3

The transformable catheter as set forth in claim 1 wherein the sheath includes at its distal end a predetermined region of weakness so that upon tension being applied to the wire, the distal end of the sheath bends in the direction of the predetermined region of weakness.

Claim 4

The transformable catheter as set forth in claim 2 wherein upon removal of the tension from the wire, the sheath to return to its original straight relaxed shape.

Claim 5

The transformable catheter as set forth in claim 1 wherein the distal tip of the inner catheter is substantially more pliable than the body of the inner catheter, whereby the inner catheter has sufficient strength to support axial and rotational movement thereof with respect to the sheath.

Claim 6

The transformable catheter as set forth in claim 1 further including means for holding the inner catheter longitudinally in place with respect to the sheath at a plurality of positions.

Claim 7

The transformable catheter as set forth in claim 1 further including means for rotating the inner catheter with respect to the sheath to allow formation of different catheter shapes at different rotational positions of the inner catheter.

Claim 8

The transformable catheter as set forth in claim 1 wherein the sheath includes a lumen extending substantially from the proximal to the distal end thereof in which the wire is disposed.

Claim 9

The transformable catheter as set forth in claim 1 wherein there is only one wire running from the proximal end of the sheath to the vicinity of the distal end of the sheath.

Claim 12

The method of changing the shape of a catheter in a human body as set forth in claim 9 wherein the shape of the distal end of the inner catheter is affected by contact with the wall of the cavity in which the catheter is disposed.

Claim 13

The method of changing the shape of a catheter in a human body as set forth in claim 9 wherein the deflecting step includes first deflecting the distal end of the sheath in a direction such that the preformed complex curve of the distal end of the inner catheter may be reformed inside the human body, and then further extending the distal end of the inner catheter distally out of the sheath to reform the complex curve of the distal end of the inner catheter inside the human body.

Claim 14

The method of changing the shape of a catheter in a human body as set forth in claim 9 wherein the distal end of the sheath is deflected and the distal tip of the inner catheter is exposed in an amount to cause the distal end of the combination catheter to assume a radius smaller than the radius achievable by deflecting the distal end of the sheath alone.

Claim 15

The method of changing the shape of a catheter in a human body as set forth in claim 9 wherein the distal end of the sheath is deflected by selectively applying tension to a wire disposed in the sheath.

Claim 20

The method of changing the shape of a catheter in a human body as set forth in claim 15 wherein the combination catheter is formed into a plurality of distinct shapes in the human body during a single medical procedure further including mechanically fixing the inner catheter in place with respect to the sheath for each of the plurality of distinct shapes.

Claim 21

A transformable catheter comprising: a substantially straight sheath having a diameter sufficiently small so that the sheath may be inserted into the human body, said sheath having a length which is substantial fraction of the entire length of the transformable catheter, and having a bore therethrough running substantially form the proximal end of the sheath to the distal end of the sheath; a preformed inner catheter having a complex curve formed into the distal end thereof, said preformed catheter being sized to fit in the sheath bore and being axially movable with respect to the sheath in the bore, said sheath being sufficiently rigid and the inner catheter being sufficiently pliable so that withdrawal of the inner catheter into the sheath substantially irons out the curve of that portion of the distal tip which is disposed in the sheath, said distal tip resuming its complex curve shape upon movement thereof completely out of the sheath bore, said inner catheter having a length substantially corresponding to the length of the transformable catheter, said complex curve having at least three curve portions having different radii of curvature, at least one of said curve portions having a direction of curvature, at least one of said curve portions having a direction of curvature retrograde to that of at least two of the other curve portions; at least one wire running from the proximal end of the sheath to the vicinity of the distal end of the sheath, said wire being connected to the sheath adjacent the distal end so as to allow the distal tip of the sheath to be deflected upon movement of said wire; whereby by suitable manipulation of the wire and of the inner catheter with respect to the sheath the shape of the exposed portion of the distal end of the inner catheter may be reformed and transformed to any of a variety of shapes as desired by the user; means for holding the inner catheter longitudinally in place with respect to the sheath at a plurality of positions; wherein the means for holding the inner catheter longitudinally in place with respect to the sheath at a plurality of positions includes means for mechanically locking the inner catheter in place with respect to the sheath, said means for mechanically locking being manually operable to unlock the inner catheter with respect to the sheath for longitudinally movement with respect thereto.

Claim 22

A transformable catheter comprising: a substantially straight sheath having a diameter sufficiently small so that the sheath may be inserted into the human body, said sheath having a length which is substantial fraction of the entire length of the transformable catheter, and having a bore therethrough running substantially form the proximal end of the sheath to the distal end of the sheath; a preformed inner catheter having a complex curve formed into the distal end thereof, said preformed catheter being sized to fit in the sheath bore and being axially movable with respect to the sheath in the bore, said sheath being sufficiently rigid and the inner catheter being sufficiently pliable so that withdrawal of the inner catheter into the sheath substantially irons out the curve of that portion of the distal tip which is disposed in the sheath, said distal tip resuming its complex curve shape upon movement thereof completely out of the sheath bore, said inner catheter having a length substantially corresponding to the length of the transformable catheter, said complex curve having at least three curve portions having different radii of curvature, at least one of said curve portions having a direction of curvature, at least one of said curve portions having a direction of curvature retrograde to that of at least two of the other curve portions; at least one wire running from the proximal end of the sheath to the vicinity of the distal end of the sheath, said wire being connected to the sheath adjacent the distal end so as to allow the distal tip of the sheath to be deflected upon movement of said wire; whereby by suitable manipulation of the wire and of the inner catheter with respect to the sheath the shape of the exposed portion of the distal end of the inner catheter may be reformed and transformed to any of a variety of shapes as desired by the user; means for holding the inner catheter longitudinally in place with respect to the sheath at a plurality of positions; wherein the means for holding the inner catheter longitudinally in place with respect to the sheath at a plurality of positions includes means for mechanically locking the inner catheter in place with respect to the sheath, said means for mechanically locking being manually operable to unlock the inner catheter with respect to the sheath for longitudinally movement with respect thereto.

Claim 23

The transformable catheter as set forth in claim 17 wherein the means for mechanically locking includes a slot and pin locking mechanism.

Claim 24

A transformable catheter comprising: a substantially straight sheath having a diameter sufficiently small so that the sheath may be inserted into the human body, said sheath having a length which is a substantial fraction of the entire length of the transformable catheter, and having a bore therethrough running substantially from the proximal end of the sheath to the distal end of the sheath; a preformed inner catheter having a complex curve formed into the distal end thereof, said preformed catheter being sized to fit in the sheath bore and being axially movable with respect to the sheath in the bore, said sheath being sufficiently rigid and the inner catheter being sufficiently pliable so that withdrawal of the inner catheter into the sheath substantially irons out the curve of that portion of the distal tip which is disposed in the sheath, said distal tip resuming its complex curve shape upon movement thereof completely out of the sheath bore, said inner catheter having a length substantially corresponding to the length of the transformable catheter, said complex curve having at least three curve portions having different radii of curvature, at least one of said curve portions having a direction of curvature retrograde to that of at least two of the other curve portions; at least one wire running from the proximal end of the sheath to the vicinity of the distal end of the sheath, said wire being connected to the sheath adjacent the distal end so as to allow the distal tip of the sheath to be deflected upon movement of said wire; whereby by suitable manipulation of the wire and of the inner catheter with respect to the sheath the shape of the exposed portion of the distal end of the inner catheter may be reformed and transformed to any of a variety of shapes as desired by the user; further including mechanical means for locking the inner catheter in at least two different rotational positions with respect to the sheath, said mechanical means for locking being manually operable for unlocking the inner catheter with respect to the sheath for movement to another rotational position with respect thereto.

Claim 25

A transformable catheter comprising: a substantially straight sheath having a diameter sufficiently small so that the sheath may be inserted into the human body, said sheath having a length which is a substantial fraction of the entire length of the transformable catheter, and having a bore therethrough running substantially from the proximal end of the sheath to the distal end of the sheath; a preformed inner catheter having a complex curve formed into the distal end thereof, said preformed catheter being sized to fit in the sheath bore and being axially movable with respect to the sheath in the bore, said sheath being sufficiently rigid and the inner catheter being sufficiently pliable so that withdrawal of the inner catheter into the sheath substantially irons out the curve of that portion of the distal tip which is disposed in the sheath, said distal tip resuming its complex curve shape upon movement thereof completely out of the sheath bore, said inner catheter having a length substantially corresponding to the length of the transformable catheter, said complex curve having at least three curve portions having different radii of curvature, at least one of said curve portions having a direction of curvature retrograde to that of at least two of the other curve portions; at least one wire running from the proximal end of the sheath to the vicinity of the distal end of the sheath, said wire being connected to the sheath adjacent the distal end so as to allow the distal tip of the sheath to be deflected upon movement of said wire; whereby by suitable manipulation of the wire and of the inner catheter with respect to the sheath the shape of the exposed portion of the distal end of the inner catheter may be reformed and transformed to any of a variety of shapes as desired by the user; further including mechanical means for locking the inner catheter in at least two different rotational positions with respect to the sheath, said mechanical means for locking being manually operable for unlocking the inner catheter with respect to the sheath for movement to another rotational position with respect thereto.