Alternative micromachined structures
Medical devices and methods for making and using the same. An example medical device may include an elongate core member and a tubular member disposed about a portion of the core member. The tubular member may have a plurality of slots formed therein. The medical devices may be configured to have a preferential bending direction.
1. A medical device, comprising:
an elongate core member having a proximal portion and a distal portion;
a tubular member disposed about the distal portion, the tubular member having a plurality of slots formed therein;
wherein the tubular member has a proximal end, a distal end, a longitudinal axis extending therebetween, and a plane extending through the longitudinal axis and along the length of the longitudinal axis, where the plane defines a first side of tubular member and a second side of the tubular member; and
wherein a wide slot is disposed along the first side of the tubular member, and wherein a plurality of narrow slots are disposed directly opposite the wide slot along the second side of the tubular member opposite the first side, the wide slot being longer in the longitudinal direction than each of the plurality of narrow slots.
2. The medical device of claim 1 , wherein the tubular member includes a nickel-titanium alloy.
3. The medical device of claim 2 , wherein the tubular member includes a linear-elastic nickel-titanium alloy.
4. The medical device of claim 2 , wherein a first portion of the tubular member includes a linear-elastic nickel-titanium alloy and a second portion of the tubular member includes a super-elastic nickel-titanium alloy.
5. The medical device of claim 4 , wherein the first portion is a proximal portion of the tubular member.
6. The medical device of claim 1 , wherein the tubular member has a first bending stiffness along the first side, wherein the tubular member has a second bending stiffness along the second side, and wherein the first bending stiffness is lower than the second bending stiffness.
7. The medical device of claim 6 , further comprising a tension member disposed within the tubular member.
8. The medical device of claim 7 , wherein tension forces can be selectively changed in the tension member.
9. The medical device of claim 7 , wherein the tension member is under tension and wherein the tubular member includes a curved region that curves along the first side.
10. The medical device of claim 1 , wherein the wide slot has a first width, wherein the plurality of narrow slots each have a second width, and wherein the first width is at least twice as long as the second width.
11. The medical device of claim 1 , wherein the tubular member is manufactured by applying compression to the tubular member to define a compressed shape and heat treating the tubular member to set the tubular member in the compressed shape.
12. The medical device of claim 11 , wherein the wide slot is only partially closed when the tubular member is in the compressed shape and wherein at least some of the narrow slots are closed when the tubular member is in the compressed shape.