Method and apparatus for translating and positioning a catheter

Claim 2

A catheter assembly, characterized in that it comprises a sheath tube (12) having an open proximal end (17) and an open distal end (14), and an inner catheter tube (11) having a proximal end (16) and a distal end (13), wherein said inner catheter tube (11) has a length greater that the length of said sheath tube (12) and an outside diameter smaller that the inside diameter of said sheath tube (12), said inner catheter tube (11) being disposed within said sheath tube (12) for telescopic movement therein to project the distal end (13) of the catheter tube (11) beyond the distal end (14) of the sheath tube (12) in response to application of axially-directed forces to--said inner catheter tube (11),and wherein actuabLe locking means (20) are provi- - ded for selectively preventing axial movement of said inner catheter tube (11) relative to said sheath tube (12) over a continuous range of axial positions of the inner catheter tube (11) relative to the sheath tube (12).

Claim 3

A catheter assembly according to claim 1, characterized in that it further comprises a hollow injection needle (19) secured to and projecting outwardly from said distal end (13) of said inner catheter tube (11) and wherein the distal end (13) of the inner catheter tube (11) is telescopically retractable into the distal end (14) of the sheath tube (12) a sufficient distance to permit the entire needle (19) to be withdrawn into the sheath tube (12).

Claim 4

A catheter assembly according to claim 1, characterized in that said sheath tube (12) is made of polyethylene and said inner catheter tube (11) is made of Teflon.

Claim 5

A catheter assembly according to claim I, characterized in that said sheath tube (12) is made of polyethylene and said inner catheter tube (11) is made of vinyl.

Claim 6

A catheter assembly according to claim 1, characterized in that said locking means comprise: an annular elastomeric washer (30) disposed in axially slidable engagement about said inner catheter tube (11) at a location beyond the proximal end (17) of said sheath tube (12); and means (21, 25) far compressing said elastomeric member (30) to preclude relative axial movement between said catheter tube (11) and said elastomeric washer (30) while permitting free flow of fluid through said catheter tube (11).

Claim 7

A catheter assembly according to claim 5, characterized in that said further means comprise: a housing member (25) disposed about said sheath tube (12), said housing member (25) having a throughbore (26) to permit axial sliding of said sheath tube (12) therein, said housing member (25) further including a stem portion (27); and a cap (21) disposed about said elastomeric washer (30) and said inner catheter tube (11) to permit axially slidable movement of said inner catheter tube (11) through said washer (30) and said cap (21), said cap (21) having an ope l . end for engaging said stem portion (27) in a locked position wherein said stem portion (27) axially compresses said elastomeric washer (30) so that it fixes the position of said inner catheter tube (11).

Claim 8

A catheter assembly according to claim 6, characterized in that said cap (21) is a hollow, generally cup-like member having a generally cylindrical wall (24) disposed concentrically about said inner catheter tube (11), and an end wall (23) opposite said open end with an aperture (41) through which said inner catheter tube (11) slidably extends, and in that said cylindrical and end walls (24,23) both axially and radially compress said elastomeric washer (30) when it is axially forced against said end wall (23) by said stem portion (27).

Claim 9

A catheter assembly according to claims 6 and 7, characterized in that said sheath tube (12) is flanged at its proximal end (17) so that it engages the stem portion (27) of said housing (25), and in that said flanged end (17) of said sheath tube (12) is forced against said elastomeric washer (30) to lock said sheath tube (12) against axial movement relative to said inner catheter tube (11) when said stem portion (27) is fully inserted into said open end of said cup-like member (21).

Claim 10

A catheter assembly according to claim 8, characterized in that said open end of the cup-like member (21) is threaded at its interior surface and in that said stem portion (27) is correspondingly threaded to mate with the said threaded interior surface of said cup-like member (21).

Claim 11

A catheter assembly according to claim 5, characterized in that it further comprises an endoscope (35) and in that said sheath tube (12) is longer than said endoscope (35), said sheath tube (12) being slidable through said endoscope (35).

Claim 12

A catheter assembly according to claim 5, characterized in that it further comprises a fitting (18) secured to the proximal end (16) of said inner catheter tube (11) for receiving a mating member connected to a source of liquid under pressure.

Claim 13

A catheter assembly, characterized in that it comprises a sheath tube (12) having an open proximal end (17) and an open distal end (14); a flexible inner catheter tube (11) having a proximal end (16), a distal-end (13), a length greater than the length of said sheath tube (12) and an outside diameter smaller than the inside diameter of said sheath tube'(12), said inner catheter tube (11) being disposed within said sheath tube (12) for telescopic movement therein to project the distal end (13) of the catheter tube (11) beyond the distal end (14) of the sheath tube (12) in response to application of axially-directed forces forces to said inner catheter tube (11); a housing member (25) disposed about said sheath tube (12), said housing member (25) having a throughbore (26) to permit axial sliding of 'said sheath tube (12) therethrough, said housing member (25) further including a stem portion (27); an annular, elastomeric member (30) disposed in axially slidable engagement about said inner catheter tube (11) at a location beyond the proximal end (17) of said sheath· tube (12); and a cup member (21) disposed about said elastomeric member (30), one end of said cap member (21) having an aperture to permit axially sliding movement of said inner catheter tube (11) through said cap member (21) and said elastomeric member (30), said cap member (21) having an open end for engaging said stem portion (27) in a locked position wherein said stem portion (27) axially compresses said elastomeric member (30) so that it will grip the inner catheter tube (11) and fix its position relative to the outer sheath tube (12).

Claim 14

A catheter assembly, characterized in that it comprises a sheath tube (12) having an open proximal end (17) and an open distal end (14); a flexible inner catheter tube (11) having a proximal end (16), a distal-end (13), a length greater than the length of said sheath tube (12) and an outside diameter smaller than the inside diameter of said sheath tube'(12), said inner catheter tube (11) being disposed within said sheath tube (12) for telescopic movement therein to project the distal end (13) of the catheter tube (11) beyond the distal end (14) of the sheath tube (12) in response to application of axially-directed forces forces to said inner catheter tube (11); a housing member (25) disposed about said sheath tube (12), said housing member (25) having a throughbore (26) to permit axial sliding of 'said sheath tube (12) therethrough, said housing member (25) further including a stem portion (27); an annular, elastomeric member (30) disposed in axially slidable engagement about said inner catheter tube (11) at a location beyond the proximal end (17) of said sheath· tube (12); and a cup member (21) disposed about said elastomeric member (30), one end of said cap member (21) having an aperture to permit axially sliding movement of said inner catheter tube (11) through said cap member (21) and said elastomeric member (30), said cap member (21) having an open end for engaging said stem portion (27) in a locked position wherein said stem portion (27) axially compresses said elastomeric member (30) so that it will grip the inner catheter tube (11) and fix its position relative to the outer sheath tube (12).

Claim 15

A locking mechanism for selectively preventing a first tube (11) from moving telescopically within a second tube (12), characterized in that it comprises: an elastomeric member (30) disposed in axially slidable engagement about a portion of said first tube (11); a housing member (25) disposed about said second tube (12), said housing (25) having a throughbore (26) to permit axial translation of said second tube (12) within said housing member (25); a cap member (21) disposed about said elastomeric member (30) and said portion of said first tube (11), said cap member (21) having an aperture in one end thereof to permit axial translation of said first'tube (11) therethrough; and means for engaging said cap member (21) and housing member (25) in a locked position wherein said housing member (25) compresses said elastomeric member (30) so that it fixes the position of said first tube (11) relative to said second tube (12).

Claim 16

A locking mechanism for selectively preventing a first tube (11) from moving telescopically within a second tube (12), characterized in that it comprises: an elastomeric member (30) disposed in axially slidable engagement about a portion of said first tube (11); a housing member (25) disposed about said second tube (12), said housing (25) having a throughbore (26) to permit axial translation of said second tube (12) within said housing member (25); a cap member (21) disposed about said elastomeric member (30) and said portion of said first tube (11), said cap member (21) having an aperture in one end thereof to permit axial translation of said first'tube (11) therethrough; and means for engaging said cap member (21) and housing member (25) in a locked position wherein said housing member (25) compresses said elastomeric member (30) so that it fixes the position of said first tube (11) relative to said second tube (12).

Claim 17

A locking mechanism according to claim 13, characterized in that said cap member (21) has a generally cylindrical wall (24) disposed concentrically about said first tube (11), an open end and an opposite end wall (23) with said aperture through which said first tube (11) slidably extends, and in that said end wall (23) is configured to both axially and radially compress said elastomeric member (30) when that member is axially forced against said end wall (23).

Claim 18

A locking mechanism according to claims 13 and 14, characterized in that said housing member (25) includes a stem portion (27) configured to permit it to be inserted axially into said cap member (21) through said open end, and in that said second tube (12) is flanged at its distal end (17) so that it engages the said stemrportion (27), the flanged end engaging said elastomeric member (30) to lock said second tube (12) against axial movement relative to said housing member (25) when said stem portion (27) is fully inserted into the open end of said cap member (21).

Claim 19

A locking mechanism according to claim 15, characterized in that said cap member (21) includes a threaded interior surface of said generally cylindrical wall (24) and in that said stem portion (27) includes a threaded periphery for engaging the threaded interior surface.

Claim 20

A locking mechanism according to claim 13, characterized in that said first tube comprises an inner catheter tube (11) and in that said second tube comprises a sheath tube (12) which together form a catheter assembly, the assembly further comprising a hollow injection needle (19) secured to and projecting outwardly from the distal end (13) of said inner catheter tube (11) and in that the distal end (13) of the inner catheter tube (11) is telescopically retractable into the distal end (14) of the sheath tube (12) a sufficient distance to permit the entire needle (19) to be withdrawn into the sheath tube (12).

Claim 22

A method according to claim 18, characterized in that it further comprises the step of: positionally locking said catheter tube (11) relative to said sheath tube (12) to preclude further telescopic translation between said tubes (11, 12).

Claim 23

A method according to claim 19, characterized in that the step of positionally locking includes the steps of: axially compressing an elastomeric member (30) disposed in concentrically slidable engagement about said catheter tube (11); and radially compressing said elastomeric member (30) to tightly grip said catheter tube (11) and preclude axial translation of the catheter tube (11) relative to said sheath tube (12) while still permitting free fluid flow through said catheter tube (11).

Claim 24

A method according to claim 19, characterized in that it further comprises the steps of: supporting the neelde (19) and distal end (13) of the catheter tube (11) with said sheath tube (12) during insertion of said needle (19) into said body part (40) to prevent bending the catheter tube (11) during insertion; thereafter unlocking the catheter tube (11) to to permit retraction of the sheath tube (12); and retracting the sheath tube (12) relative to the catheter tube (11) after insertion of the needle (19) into the body part (40).