DEVICES AND METHODS FOR PERFORMING PERCUTANEOUS SURGICAL PROCEDURES

• US 20110166566A1
• Filed: 07/01/2010
• Published: 07/07/2011
• Est. Priority Date: 07/02/2009
• Status: Abandoned Application

• Current Assignee: LOMA Linda University Medical Center (Mission Healthcare Services LLC)
• Original Assignee: LOMA Linda University Medical Center (Mission Healthcare Services LLC)
• Inventors: Gabriel, Simon
• Application Number:
  US12/991,852
• Publication Number:
  US 20110166566A1
• Time in Patent Office: Days
• US Class Current: 606/34
• CPC Class Codes: 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
• CPC Class Codes: A61M 2025/09133 having specific material compositions or coatings; Materials with specific mechanical behaviours, e.g. stiffness, strength to transmit torque
• CPC Class Codes: A61M 2025/0915 having features for changing the stiffness
• CPC Class Codes: A61M 25/0053 having a variable stiffness along the longitudinal axis, e.g. by varying the pitch of the coil or braid
• CPC Class Codes: A61M 25/09 Guide wires

Abstract

A guidewire or a catheter with a stiffness that can be varied during use inside a human body, where the guidewire or the catheter comprises a magnetorheological fluid. A guidewire comprising a proximal section, a distal section, and an intermediate section connecting the proximal section and the distal section, where the intermediate section comprises a longitudinal axis, and the distal section comprises a longitudinal axis, and where the longitudinal axis of the distal section can be coincident with the longitudinal axis of the intermediate section or can be controllably made non-coincident with the longitudinal axis of the intermediate section during use inside a human body, and the guidewire further comprises a plurality of piezoelectric cores and one or more than one piezoelectric strut.

Claims

1. A guidewire with a stiffness that can be varied during use, the guidewire comprising:

a) a proximal end and a distal end, and oriented from the proximal end to the distal end, a proximal section, an intermediate section and a distal section, where the intermediate section connects the proximal section to the distal section;

b) an outer layer comprising and defined by an outer surface of the outer layer and an opposing inner surface of the outer layer;

c) a central fluid layer defined by the inner surface of the outer layer, and surrounded by the outer layer;

d) a longitudinal length between the proximal end and the distal end; and

e) a cross-sectional area defined by the outer surface of the outer layer;

where the outer layer further comprises one or more than one circumferential wire comprising a material that generates a magnetic field in response to the application of electric current;

where the central fluid layer comprises magnetorheological fluid comprising a suspension of micrometer-sized magnetic particles suspended in a carrier fluid; and

where the central fluid layer further comprises a viscosity.

43. A system for performing a procedure within a human body, the system comprising:

a) one or more than one guidewire according to claim 1; and

b) a control for controllably sending electric current through the one or more than one circumferential wire;

where the control is connected to the guidewire through the proximal section of the guidewire.

44. A method for performing a procedure within a human body, the method comprising:

a) providing a guidewire according to claim 1; and

b) using the guidewire to perform the procedure.

45. A method for performing a procedure within a human body, the method comprising:

a) providing a system according to claim 43; and

b) generating electric current through the control and sending electric current through the one or more than one circumferential wire, thereby creating a magnetic flux in the fluid layer causing the magnetic particles suspended in the carrier fluid to become aligned which increases the viscosity of the fluid by decreasing the ability of the carrier fluid to flow around the particles, thereby controllably increasing the stiffness of the guidewire.

2-42. -42. (canceled)

46. A catheter with a stiffness that can be varied during use inside a human body, the catheter comprising:

a) a proximal end and a distal end, and oriented from the proximal end to the distal end, a proximal section, an intermediate section and a distal section, where the intermediate section connects the proximal section to the distal section;

b) an outer layer comprising and defined by an outer surface of the outer layer, and an opposing inner surface of the outer layer;

c) an inner layer comprising and defined by an outer surface of the inner layer, and an opposing inner surface of the inner layer;

d) a fluid layer between and defined by the inner surface of the outer layer, and the outer surface of the inner layer;

e) a central lumen defined by the inner surface of the inner layer;

f) a longitudinal length between the proximal end and the distal end; and

g) a cross-sectional area defined by the outer surface of the outer layer;

where the outer layer of the catheter comprises and is defined by an outer surface of the outer layer;

where the outer layer further comprises one or more than one circumferential wire comprising a material that generates a magnetic field in response to the application of electric current;

where the fluid layer comprises magnetorheological fluid comprising a suspension of micrometer-sized magnetic particles suspended in a carrier fluid; and

where the magnetorheological fluid comprises a viscosity.

47-102. -102. (canceled)

103. A guidewire than can be controllably bent during use, the guidewire comprising:

a) a proximal end and a distal end, and oriented from the proximal end to the distal end, a proximal section, an intermediate section and a distal section, where the intermediate section connects the proximal section to the distal section;

b) a longitudinal axis of the proximal section, a longitudinal axis of the intermediate section, and a longitudinal axis of the distal section, where the longitudinal axis of the intermediate section connects the longitudinal axis of the proximal section to the longitudinal axis of the distal section, and where the longitudinal axis of the proximal section, the longitudinal axis of the intermediate section, and the longitudinal axis of the distal section define a longitudinal axis of the guidewire;

c) a longitudinal length between the proximal end and the distal end;

d) one or more than one outer layer comprising and defined by an outer surface of the outer layer, and an opposing inner surface of the outer layer;

e) a central layer defined by the inner surface of the outer layer, and surrounded by the outer layer;

f) a cross-sectional area defined by the outer surface of the outer layer;

g) one or more than one actuator base, each actuator base comprising a base plate, a first piezoelectric core, a second piezoelectric core, a first brace, a second brace, and a pivot connecting the first brace to the second brace; and

h) one piezoelectric strut comprising a piezoelectric material associated with each actuator base;

where the base plate spans the central layer between the inner surface of the outer layer and is attached to two opposing locations of the inner surface of the outer layer;

where the first piezoelectric core is adjacent the base plate, and extends across the central layer between the inner surface of the outer layer without contacting the inner surface of the outer layer at any location;

where the second piezoelectric core extends across the central layer between the inner surface of the outer layer without contacting the inner surface of the outer layer at any location;

where the first piezoelectric core comprises a long axis, and the second piezoelectric core comprises a long axis;

where the second piezoelectric core is spaced apart from the first piezoelectric core at a distance x, and the long axis of the first piezoelectric core is parallel to the long axis of the second piezoelectric core;

where the first piezoelectric core and the second piezoelectric core comprise a piezoelectric material;

where the first brace comprises a proximal end and a distal end;

where the second brace comprises a proximal end and a distal end;

where the first brace comprises a first casing at the proximal end of the first brace and a second casing at the distal end of the first brace;

where the second brace comprises a first casing at the proximal end of the second brace and a second casing at the distal end of the second brace;

where the first casing of the first brace and the first casing of the second brace surround opposing ends of the first piezoelectric core;

where the second casing of the first brace and the second casing of the second brace surround opposing ends of the second piezoelectric core;

where the first casing of the first brace comprises a first portion of a first connector and the base plate comprises a second portion of a first connector;

where the first casing of the second brace comprises a first portion of a second connector and the base plate comprises a second portion of a second connector;

where the first connector and the second connector allow the first piezoelectric core to expand longitudinally thereby increasing longitudinal dimension toward the inner surface of the outer layer while maintaining a relative distance to the base plate;

where the piezoelectric strut comprises a proximal end and a distal end;

where the proximal end of the piezoelectric strut is connected to either the second casing of the first brace or the second casing of the second brace; and

where the distal end of the piezoelectric strut is connected to the inner surface of the outer layer in the distal section of the guidewire.

105. The guidewire of claim 103, where the longitudinal length of the guidewire is between 50 cm and 250 cm.

106. The guidewire of claim 103, where the longitudinal length of the guidewire is between 100 cm and 200 cm.

107. The guidewire of claim 103, where the cross-sectional area is between 0.4 mm² and 4.0 mm²

108. The guidewire of claim 103, where the cross-sectional area is between 0.4 mm² and 1.0 mm².

109. The guidewire of claim 103, where the distal section of the guidewire is tapered at the distal end of the guidewire.

110. The guidewire of claim 103, where the outer layer comprises a biocompatible material selected from the group consisting of an epoxy resin and a polyurethane resin.

111. The guidewire of claim 103, where the base plate comprises polyurethane or an epoxy resin composite.

112. The guidewire of claim 103, where the first portion of the first connector and the first portion of the second connector are male type extensions, and the second portion of the first connector and the second portion of the second connector are female type portions such as slotted grooves which mate with the male type extensions.

113. The guidewire of claim 103, further comprising micrometer sized ball bearings between the first portion of the first connector and the second portion of the first connector, or between the first portion of the second connector and the second portion of the second connector to decrease friction.

114. The guidewire of claim 103, where the first portion of the first connector and the second portion of the first connector, or the first portion of the second connector and the second portion of the second connector comprise a coating to decrease friction.

115. The guidewire of claim 103, where the first brace and the second brace comprise iron or aluminum

116. The guidewire of claim 103, where the first brace and the second brace comprise hardened polyurethane.

117. The guidewire of claim 103, where the first casing of the first brace, the second casing of the first brace, the first casing of the second brace and the second casing of the second brace each comprise a plastic such as hardened polyurethane.

118. The guidewire of claim 103, where the pivot is a screw comprising a head at one end and a distal end extending through matching holes in the center of the first brace and the center of the second brace, where the pivot comprises a transverse hole in the distal end to receive a pin, thereby fixing the pivot in place with respect to the first brace and the second brace.

119. The guidewire of claim 103, comprising one actuator base and associated piezoelectric strut.

120. The guidewire of claim 103, comprising a plurality of actuator bases and associated piezoelectric struts.

121. The guidewire of claim 103, comprising two actuator bases and associated piezoelectric struts.

122. The guidewire of claim 103, comprising three actuator bases and associated piezoelectric struts.

123. The guidewire of claim 103, comprising four actuator bases and associated piezoelectric struts.

124. The guidewire of claim 103, comprising more than four actuator bases and associated piezoelectric struts.

125. The guidewire of claim 103, where the guidewire comprises a plurality of actuator bases, each actuator base associated with one piezoelectric strut;

and

where the actuator bases are spaced apart from each other longitudinally, and are rotated relative to one another axially, thereby causing the distal end of each piezoelectric strut to be connected to the inner surface of the outer layer in the distal section of the guidewire at a different location.

126. A system for performing a procedure within a human body, the system comprising:

a) one or more than one guidewire according to claim 103; and

b) a control connected to the guidewire for controlling the function of the guidewire.

127. The system of claim 126, where the guidewire further comprises wiring connecting the first piezoelectric core and the second piezoelectric core to the control for controlling transmission of current from the control to the first piezoelectric core and the second piezoelectric core.

128. The system of claim 126, where the guidewire further comprises wiring connecting the piezoelectric strut to the control for controlling transmission of current from the control to the piezoelectric strut.

129. The system of claim 126, where the guidewire comprises separate wiring connecting the first piezoelectric core and the second piezoelectric core of each actuator base to the control for controlling transmission of current from the control to the first piezoelectric core and the second piezoelectric core.

130. The system of claim 126, where the guidewire further comprises separate wiring connecting the piezoelectric strut associated with each actuator base to the control for controlling transmission of current from the control to the piezoelectric strut.

131. A method for performing a procedure within a human body, the method comprising:

a) providing a guidewire according to claim 103; and

b) using the guidewire to perform the procedure.

132. A method for performing a procedure within a human body, the method comprising:

a) providing a system according to claim 126; and

b) using the system to perform the procedure.

133. A method for performing a procedure within a human body, the method comprising:

a) providing a guidewire according to claim 103;

b) inserting the guidewire in a first configuration into an arterial lumen of the patient percutaneously;

c) supplying current to the one or more than one piezoelectric strut rendering the one or more than one piezoelectric strut in a first longitudinal length, and no current is being supplied to the one or more than one first piezoelectric core and the second piezoelectric core rendering them in a first longitudinal length, where the longitudinal axis of the distal section of the guidewire is coincident with the longitudinal axis of the intermediate section of the guidewire; and

d) in order to negotiate a curve of the arterial lumen, changing the guidewire into a second configuration by supplying current to the wiring to the one or more than one first piezoelectric core and the second piezoelectric core rendering them in a second longitudinal length and increasing the distance x, the axial separation of first piezoelectric core and the second piezoelectric core and decreasing the separation of the first casing of the first brace from the first casing of the second brace, and the separation of the second casing of the first brace from the second casing of the second brace, and by simultaneously ceasing to supply current to the wiring to the one or more than one piezoelectric strut rendering the one or more than one piezoelectric strut in a second longitudinal length;

where the first longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core is longer than the second longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core; and

where the first longitudinal length of the one or more than one piezoelectric strut is shorter than the second longitudinal length of the one or more than piezoelectric strut, thereby causing the longitudinal axis of the distal section of the guidewire to become non-coincident with the longitudinal axis of the intermediate section of the guidewire.

134. The method of claim 133, where the first longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core is longer than the second longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core by at least 25%.

135. The method of claim 133, where the first longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core is longer than the second longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core by at least 50%.

136. The method of claim 133, where the first longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core is longer than the second longitudinal length of the one or more than one first piezoelectric core and the second piezoelectric core by at least 100%.

137. The method of claim 133, where the second longitudinal length of the one or more than one piezoelectric strut is longer than the first longitudinal length of the one or more than piezoelectric strut by at least 25%.

138. The method of claim 133, where the second longitudinal length of the one or more than one piezoelectric strut is longer than the first longitudinal length of the one or more than piezoelectric strut by at least 50%.

139. The method of claim 133, where the second longitudinal length of the one or more than one piezoelectric strut is longer than the first longitudinal length of the one or more than piezoelectric strut by at least 100%.

104. A guidewire than can controllably bend during use, the guidewire comprising a plurality of piezoelectric struts comprising a piezoelectric material.