Guide for medical devices

A guide for controlling the orientation of a medical device includes a cannula having a lumen therein for the medical device, and a guide member having a passage therein for receiving and directing the medical device, the guide member being movably mounted in the cannula for movement. The guide member can be magnetically responsive to an externally applied magnetic field, or can be magnetically responsive to an externally applied magnetic field when a magnetic medical device is in the passage, and/or it can be mechanically responsive.

BACKGROUND OF THE INVENTION

This invention relates to medical devices, and in particular to a guide for controlling the orientation or direction of a medical device.

Control of medical devices inside the body is a persistent problem. It is important to accurately control medical devices so that they quickly and effectively perform their diagnostic or therapeutic function, while minimizing collateral damage to surrounding tissue. A particular difficulty has been selectively controlling the direction in which a medical device is deployed from a location inside the body, for example while implanting a deep brain stimulator. With the equipment and methods presently available, the placement of a device in the brain frequently involves forming a straight path to the site from a burr hole in the skull. When several devices are placed in the brain, or when a single device is placed in several locations, a number of separate paths are made from the burr hole to the separate locations. It would be preferred to have a single main path from the burr hole with a plurality of branches extending to the separate locations. However there is no device that accurately and easily guides medical devices in a plurality of separate branches. Similar problems are encountered when navigating through other body tissues.

Another difficulty with the prior art devices is the accurate navigation of medical devices in body lumens and cavities. It is often desired to deploy a medical device in a body lumen or cavity in a particular direction, or to make contact in a particular orientation, for example with the needles used in the delivery of gene therapy, particularly in the heart.

SUMMARY OF THE INVENTION

Generally, the present invention relates to a guide for deploying a medical device in the body. The guide comprises a cannula, having a proximal end, a distal end, and lumen therebetween. There is a guide member, with a passage therethrough movably mounted in the lumen of the cannula. The guide member can be magnetically or mechanically moved to change the orientation of the passage in the guide member, and thus the direction of deployment of a medical device from the guide. The guide thus allows the direction of deployment of a medical device to be precisely controlled, and further allows a medical device to be deployed in a number of separate paths from the same device. The guide also facilitates the automation of the deployment of medical devices.

The guide of this invention can also be used to orient a built-in device, such as a sensor or camera or fiber optic lead, or a therapeutic component such as a laser.

These and other features and advantages will be in part apparent and in part pointed out hereinafter.

DETAILED DESCRIPTION OF THE INVENTION

A first embodiment of a guide for a medical device constructed according to the principles of this invention is indicated generally as20inFIGS. 1 through 5. The guide20comprises a cannula22, having a proximal end24, and a distal end26, and a lumen28therethrough. The cannula22is preferably fairly stiff or rigid, made from any suitable material, such as a non-magnetic stainless steel. Of course in appropriate applications, the cannula22could be flexible. There is a guide member30in the cannula22, mounted for movement in response to an applied magnetic field. In the first preferred embodiment shown in the Figures, the distal end26has a lip32for retaining the guide member30in the cannula. Me guide member30has a passage34therethrough for orienting or guiding a magnetic medical device.

The guide member30is preferably generally spherical, and the passage extends generally diametrically through the sphere. The guide member30is preferably made of a magnetic material so that the guide member moves in response to an externally applied magnetic field. This magnetic material may either be a permeable magnetic material, or preferably a permanent magnetic material. A permanent magnetic material allows the guide member to have a permanent magnetic orientation so that when a magnetic field is applied, the direction of the guide member is precisely controlled. When a permeable magnetic material is used, the orientation of the guide member can be ambiguous, and to prevent the guide member from assuming an undesirable orientation, stops (not shown) may be provided on the guide member. Of course, instead of, or in addition to making the guide member magnetically responsive, the distal end of the medical device can provided with a magnet, and when the magnet on the distal end of the medical device is in the passage, the magnet makes the guide member magnetically responsive.

The guide20preferably further comprises a lock for selectively locking the guide member30in a selected orientation. In this preferred embodiment the lock is a sleeve36, with a beveled distal end38for engaging the guide member, that can be advanced distally to engage and lock the guide member30, and retracted proximally to release the guide member to allow it to move in response to an applied magnetic field. The sleeve36is preferably biased with a spring, which mediates the force applied on the guide member preventing deformation of the guide member, and reducing the risk that the guide member will be pushed from the distal end of the guide.

As shown inFIGS. 2 and 4, when the lock is not engaged, the guide member30can freely move in response to an applied magnetic field from a first orientation, shown inFIGS. 2 and 3to a second orientation as shown inFIGS. 4 and 5. As illustrated inFIGS. 6 and 7, this allows the direction of deployment of a medical device to be selectively controlled. When a medical device40is advanced through the guide, it passes through the lumen28in the cannula22, and into the passage34in the guide member30. The medical device40thus exits the guide20in a selected direction depending on the orientation of the guide member30. Thus, when the guide member is in a first position or orientation as shown inFIGS. 2 and 3, it directs the medical device40in a first direction or orientation as shown inFIG. 6, and when the guide member is in a second position or orientation as shown inFIGS. 4 and 5, it directs the medical device40in a second direction or orientation as shown inFIG. 7.

The orientation and deployment of the medical device40can be easily controlled. Once a desired direction is determined, one or more externally electromagnets can be energized and/or positioned to provide the necessary magnetic field to orient the guide member30in the direction necessary to achieve the desired direction of the medical device, and/or one or more permanent magnets can positioned and/or oriented to provide the necessary magnetic field to orient the guide member30in the direction necessary to achieve the desired direction of the medical device. The orientation and deployment of the medical device can even be automated, for example using a computer interface that allows the user to select a desired direction or even a desired destination for the deployment of the medical device. A computer can then determine the magnetic field necessary to properly orient the guide member to achieve the desired direction or the desired destination point or points, or volume or surface of points, and operate one or more electromagnets and/or one or more permanent magnets to achieve the necessary magnetic field. An advancer can automatically advance the medical device when the guide member is in the proper orientation.

Thus, the guide20can be used to deploy any type of medical device in the body, including catheters and cannulas, endoscopes, laser devices, RF devices, cryo devices, drug needles, biopsy tools, physiological sensors, deep brain stimulators, or other diagnostic and therapeutic devices. The guide20can also be used to orient various types of imaging and sensing equipment for example digital cameras, infrared sensors, and ultrasonic sensors.

A first alternate construction of the guide, indicated generally as20′, is shown inFIG. 8. The guide20′ is similar in construction guide20, and corresponding parts are identified with corresponding reference numerals, except that in guide20′ the guide member30′ is made of a composite of permeable magnetic material and permanent magnetic material. In particular the guide member30′ comprises a tube42of a permanent magnetic material, and a generally spherical body44of permeable magnetic material.

A second alternate construction of the guide, indicated generally as20″, is shown inFIG. 9. The guide20″ is similar in construction guide20, and corresponding parts are identified with corresponding reference numerals, except that in guide20″ the passage34″ in the guide member30″ does not extend diametrically through guide member. This allows the proximal end of the passage to remain generally in the center of the lumen28, facilitating the passage of medical devices40. The medical device can still be deployed in any orientation by a combination of a relatively small movement of the guide member30″ together with a rotation of the guide member generally about the axis of the cannula22.

As shown inFIGS. 6 and 7, the medical device40can have one or more magnetically responsive elements, such as magnets42adjacent its distal end, so that after it is deployed is the desired initial direction, the distal end can be navigated with the assistance of the externally applied magnetic field. The magnets42can be any permanent magnet material, such as a Neodymium-Iron-Boron (Nd—Fe—B) compound. Alternatively, instead of a permanent magnetic material, the magnet42could be a permeable magnetic material.

A second embodiment of a guide constructed according to the principles of this invention is indicated generally as100inFIG. 10. The guide100comprises a cannula102, having a proximal end104, and a distal end106, and a lumen108therethrough. The cannula102is preferably fairly stiff or rigid, made from any suitable material, such as a non-magnetic stainless steel. There is a guide member110in the cannula102, mounted for movement in response to an applied magnetic field. In the first preferred embodiment shown inFIG. 10, the distal end106has a lip112for retaining the guide member110in the cannula. The guide member110has a passage114therethrough for orienting or guiding a magnetic medical device.

The guide member110is preferably generally spherical, and the passage114extends generally diametrically through the sphere. The guide member110is preferably made of a magnetic material so that the guide member moves in response to an externally applied magnetic field. This magnetic material may either be a permeable magnetic material, or preferably a permanent magnetic material. A permanent magnetic material allows the guide member to have a permanent magnetic orientation so that when a magnetic field is applied, the direction of the guide member is precisely controlled. When a permeable magnetic material is used, the orientation of the guide member can be ambiguous, and to prevent the guide member from assuming an undesirable orientation, stops (not shown) may be provided on the guide member.

The guide100preferably further comprises a lock for selectively locking the guide member110in a selected orientation. In this preferred embodiment, the lock is a sleeve116, with a beveled distal end118for engaging the guide member, that can be advanced distally to engage and lock the guide member110, and retracted distally to release the guide member to allow it to move in response to an applied magnetic field. The sleeve116is preferably biased with a spring, which mediates the force applied on the guide member preventing deformation of the guide member, and reducing the risk that the guide member will be pushed from the distal end of the guide.

The guide100further comprises three coils120,122, and124mounted on, or formed in the sidewall of the cannula102. Coils120is oriented generally axially, and has leads126and128for selectively powering the coil. Coil122is also oriented generally axially, but is offset90′ from coil120, so that the coils are in effect in mutually perpendicular planes. Leads130and132extend from the coil122for selectively powering the coil. Coil124is oriented circumferentially around the wall of the cannula102, so that coil124is in a plane generally perpendicular to coils120and122, and thus all three coils are in mutually perpendicular planes. Leads134and136extend from coil124for selectively powering the coil. The three coils120,122, and124can be selectively powered to create a local magnetic field in virtually any direction to orient the guide member110. Thus the guide member110can be selectively oriented, by controlling power to the coils, and when the guide member is in the desired position, a medical device can be advanced through the lumen of the cannula, and through the passage114in the desired direction.

The coils can alternatively or additionally be used to sense the orientation of the guide member, in order to confirm the direction in which a medical device will exit the guide100.

A third embodiment of a guide for a medical device constructed according to the principles of this invention is indicated generally as200inFIGS. 11 through 14. The guide200comprises a cannula202, having a proximal end204, and a distal end206, and a lumen208therethrough. The cannula202is preferably fairly stiff or rigid, made from any suitable material such as a non-magnetic stainless steel. There is a guide member210in the cannula202, mounted for movement in response to an applied magnetic field. In the first preferred embodiment shown in the Figures, the distal end206has a lip212for retaining the guide member210in the cannula. The guide member210has a passage214therethrough for orienting or guiding a magnetic medical device.

The guide member210is preferably generally spherical, and the passage extends generally diametrically through the sphere.

The guide200preferably further comprises a lock for selectively locking the guide member30in a selected orientation. In this preferred embodiment the lock is a sleeve216, with a beveled distal end218for engaging the guide member, that can be advanced distally to engage and lock the guide member210, and retracted distally to release the guide member to allow it to move in response to an applied magnetic field. The sleeve216is preferably biased with a spring, which mediates the force applied on the guide member preventing deformation of the guide member, and reducing the risk that the guide member will be pushed from the distal end of the guide.

The guide200further comprises some apparatus for mechanically or hydraulically changing the direction of the guide member210, for example a plurality of pull wires for mechanically changing the orientation of the guide member. In the preferred embodiment there are four pull wires220,222,224, and226, attached to the guide member210, and extending to the proximal end of the guide200. The four pull wires are preferably arranged in opposing pairs220,222and224,226, with each pair 90° apart. The four pull wires220,220,224, and226can be selectively pulled to change the orientation of the guide member, and thus the orientation of the passage214, so that when a medical device is fed through the lumen208of the cannula202and through the passage214, it exits the guide in the selected direction. As shown inFIGS. 11 and 12, the magnetic member210is in a neutral position. By operating the guide wire220, the magnetic member210changes orientation, to deliver a medical device in a different direction.

A fourth embodiment of a guide constructed according to the principles of this invention is indicated generally as300inFIG. 13. The guide300comprises a cannula302, having a proximal end304, and a distal end306, and a lumen308therethrough. The guide300further comprises a plate310, intermediate the proximal and distal ends by which the guide can be secured to the skull of a patient. The cannula is threadedly connected to the plate so that the cannula can be threaded into and out of the patient's brain. The cannula302is preferably fairly stiff or rigid, made from any suitable material, such as a non-magnetic stainless steel. There is a guide member312at the end of the cannula302, mounted for movement in response to an applied magnetic field. In the first preferred embodiment shown in the Figures, the distal end306has a lip314for retaining the guide member312in the cannula. The guide member312has a passage316therethrough for orienting or guiding a magnetic medical device, such as the electrode318of a deep brain stimulator.

The guide member312is preferably generally spherical and the passage extends generally diametrically through the sphere. The guide member312is preferably made of a magnetic material so that the guide member moves in response to an externally applied magnetic field. This magnetic material may either be a permeable magnetic material, or preferably a permanent magnetic material. A permanent magnetic material allows the guide member to have a permanent magnetic orientation so that when a magnetic field is applied, the direction of the guide member is precisely controlled. When a permeable magnetic material is used, the orientation of the guide member can be ambiguous, and to prevent the guide member from assuming an undesirable orientation, stops (not shown) may be provided on the guide member.

The guide300preferably further comprises a lock for selectively locking the guide member300in a selected orientation. In this preferred embodiment, the lock is a sleeve322inside the cannula, with a beveled distal end324for engaging the guide member, that can be advanced distally to engage and lock the guide member312, and retracted distally to release the guide member to allow it to move in response to an applied magnetic field. The sleeve322is preferably biased with a spring326, which mediates the force applied on the guide member preventing deformation of the guide member, and reducing the risk that the guide member will be pushed from the distal end of the guide. A collar328, with a lock330, is provided on the cannula302for securing the sleeve322in position against the guide member312.

A burr hole is made in the skull, and the distal end306of the cannula is inserted through the hole and into the brain. The plate310is secured to the skull. The guide member312is oriented in the appropriate direction so that the passage314is aligned with the desired direction of deployment of the electrode. Once the proper orientation of the guide member312is achieved, the guide member312is locked by urging collar328downwardly, to urge sleeve322, via spring326, down against the guide member312. The spring326helps to prevent the sleeve from damaging the guide member312, or expelling it from the distal end306of the cannula302.

A deep brain stimulator is advanced through the lumen308of the cannula302, to the guide member312. The electrode passes out the passage316in the direction of the passage. The electrode318, preferably has a magnet320adjacent its distal end so that after the guide member312is locked, the distal end of the electrode can be navigated to its desired location by the application of an external magnetic field. By automating the control of the external magnetic field, and the advancement of the electrode, the placement of the electrode can be automated. This is particularly true where through localization (e.g., electromagnetic localization) or visualization (e.g., biplanar fluoroscopy), the exact position of the electrode ran be determined, so that feed back can be provided to the automated navigation process. The user can simply identify the desired end point on two screens of a bi-planer fluoroscopic imaging system, or the user can identify the desired end point on a pre-procedure image, such as an MRI. Through computer control, the distal end of the electrode can be brought to the selected location.FIG. 17shows a cone containing the possible orientations that can be achieved with by the guide.

An alternative construction of the guide of the fourth embodiment, indicated generally as300′ inFIG. 18, is shown as it would be positioned though the skull of the patient. Guide300′ is similar in construction to guide300, and corresponding parts are identified with corresponding reference numerals. However, unlike guide300, guide300′ has a dome332, into which the deep brain stimulator can be withdrawn (as shown in dashed lines) while the guide member is being re-oriented. This allows the guide to be left in place and used to move or place an additional deep brain stem in the head of a patient.

A fifth embodiment of a redirection device constructed according to the principles of this invention is indicated generally as300inFIGS. 19-22. As shown inFIGS. 19 and 21, the redirection device400comprises an outer section402and an inner section404. The outer section402is generally tube-shaped, comprising a sidewall406, having a proximal end408, a distal end410, and a lumen412therebetween. The distal end410is substantially closed, having a passage414therein. The passage414is preferably eccentrically positioned in the closed end410(i.e., it is preferably not located at the center of the end). The inner section404is of similar construction to the outer section402, and is generally tube-shaped, comprising a sidewall416, having a proximal end418, a distal end420, and a lumen422therebetween. The distal end420is substantially closed, having a passage424therein. The passage424is preferably eccentrically positioned in the closed end420(i.e., it is preferably not located at the center of the end).

The outer section402and the inner section404are relatively rotatable, i.e., the inner section404can rotate relative to the outer section402. If at least one of the passages414in the outer section and424in the inner section is eccentric, the relative rotation of the outer and inner sections causes a medical device, such as a catheter, that extends through the two passages to change direction. Thus, as shown inFIG. 19, when the outer and inner sections402and404are positioned so that their passages414and424are aligned, a catheter extending through the redirection device400extends from the device generally parallel to the axis of the distal end portion. However, as shown inFIG. 21, when the outer and inner sections402and404are rotated relative to each other, such that their passages414and424are not aligned, a catheter extending through the redirection device, extends from the device at an angle determined by the relative positions of the outer and inner sections402and404. By controlling the relative positions by rotating the outer and/or inner sections, the physician can direct a catheter or other medical device in selected directions.

A sixth embodiment of a redirection device constructed according to the principles of this invention is indicated generally as450inFIGS. 23 and 24. As shown inFIGS. 23 and 24, the redirection device450comprises a cannula452, having a sidewall454with a proximal end456and a distal end458, and a lumen460therebetween. There is a preferably a stricture462at the distal end458retaining a guide member therein. This stricture462can be formed integrally in the distal end of the sidewall454, or it can be a separate piece secured on the distal end of the cannula452. A guide member464is disposed in the lumen460of the cannula452, adjacent the distal end458. The guide member464includes a spherical body466, having a magnetic tube468mounted thereon. The spherical body466may be but need not be made of a magnetically responsive material (i.e., a permanent magnetic material, or a permeable magnetic material), but the magnetic tube468is made of a magnetically responsive material, either a permanent magnetic material, such as Nd—Fe—B, or a permeable magnetic material. A passage470extends through the spherical body466and the magnetic tube468. A flexible sheath472, having a lumen474therethrough, extends proximally from the passage470. The sheath472may incorporate a coil or braid to prevent kinking. An elongate magnetic medical device can be advanced through the lumen474of the sheath472, into the passage470through the spherical body466and the magnetic tube468. The orientation of the magnetic tube469, and thus the direction that the medical device leaves the redirection device450can be controlled by applying a magnetic field with an external magnet system, which may include one or more electromagnets and/or permanent magnets. An interface can be provided to allow the physician to select the direction in which to direct the medical device, and operate the external magnetic system to apply the appropriate magnetic field to orient the magnetic tube in the correct direction. The device can then be advanced in the selected direction. A lock mechanism, as described above, can be provided to secure the guide member464in a selected position.

The guide450can be used in automatically deploying devices. An interface can receive the physician's input on a direction and/or destination, control the external magnet system to orient the guide in the proper direction, and control an advancer to automatically advance the medical device through the guide in the proper direction, for the proper distance.

A seventh embodiment of a redirection device is indicated generally as500inFIGS. 25-28. As shown inFIGS. 25 and 26, the redirection device500comprises a cannula502, having a sidewall504with a proximal end506and a distal end508, and a lumen510therebetween. There is a preferably a stricture512at the distal end508retaining a guide member therein. This stricture512can be formed integrally in the distal end of the sidewall504, or it can be a separate piece secured on the distal end of the cannula502. A guide member514is disposed in the lumen510of the cannula502, adjacent the distal end508. As shown inFIG. 28, the guide member514includes a spherical body516. The spherical body516is made from, or includes, a magnetically responsive material. In particular it may be made from or include a permanent magnetic material, such as Nd—Fe—B, or a permeable magnetic material. A passage520extends through the spherical body516. A flexible sheath522, having a lumen524therethrough, extends proximally from the passage520. The sheath522may incorporate a coil or braid to prevent kinking. There may be a conical cut out518in the spherical body516to accommodate the sheath522as the spherical body moves to guide a medical device, as described below. An elongate magnetic medical device can be advanced through the lumen524of the sheath522, into the passage520through the spherical body516. The orientation of the spherical body516, and thus the direction that the medical device leaves the redirection device500can be controlled by applying a magnetic field to the spherical body. In this seventh preferred embodiment this is accomplished with three magnetic coils incorporated into the cannula502.

As shown inFIG. 27, three coils524,526, and528are embedded in the wall of the cannula502. Coil524is arranged in a plane parallel to the longitudinal axis of the cannula, and has leads530and532extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. Coil526is arranged in a plane parallel to the longitudinal axis of the cannula, and perpendicular to the plane of coil524, and has leads534and536extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. Coil528is arranged in a plane perpendicular to the longitudinal axis of the cannula, and has leads538and540extended therefrom so that the coil can be selectively connected to a power source to create a magnetic field. By selectively connecting the coils524,526, and528to a power source, a magnetic field can be created in the vicinity of the spherical body516to orient the body in a selected direction.

Of course fewer coils could be provided, or coils in some other arrangement could be provided. The range of motion of the spherical body516is limited, so it may not be necessary to be able to provide a magnetic field in any direction, as is possible with the three mutually orthogonal coils524,526, and528.

An interface can be provided to allow the physician to select the direction in which to direct the medical device, and energize the coils524,526, and528to apply the appropriate magnetic field to orient the spherical body516in the correct direction. The device can then be advanced in the selected direction. A lock mechanism, as described above, can be provided to secure the guide in a position.

The guide500can be used in automatically deploying medical devices. An interface can receive the physician's input on a direction and/or destination, control the coils524,526, and528to orient the guide in the proper direction, and control an advancer to automatically advance the medical device through the guide in the proper direction, for the proper distance.

An eighth embodiment of a redirection device constructed according to the principles of this invention is indicated generally as550inFIGS. 29 and 30. As shown inFIGS. 29 and 30, the redirection device550comprises a cannula552, having a sidewall554with a proximal end556and a distal end558, and a lumen560therebetween. There is a preferably a stricture562at the distal end568retaining a guide member therein. This stricture562can be formed integrally in the distal end of the sidewall554, or it can be a separate piece secured on the distal end of the cannula552. A guide member564is disposed in the lumen560of the cannula562, adjacent the distal end568. The guide member564includes a spherical body566. The spherical body566is made from, or includes, a magnetically responsive material. In particular it may be made from or include a permanent magnetic material, such as Nd—Fe—B, or a permeable magnetic material. A passage570extends through the spherical body566. A flexible sheath572, having a lumen574therethrough, extends proximally from the passage520. The sheath572may incorporate a coil or braid to prevent kinking. There may be a conical cut out in the conical body566to accommodate the sheath572as the spherical body moves to guide a medical device, as described below.

As shown inFIGS. 29 and 30an extension580comprises a cannula582, having a sidewall582with a proximal end586and a distal end588, and a lumen590therebetween. The proximal end584is secured to the spherical body566. There is a preferably a stricture592at the distal end558retaining a guide member therein. This stricture592can be formed integrally in the distal end of the sidewall582, or it can be a separate piece secured on the distal end of the cannula582. A guide member594is disposed in the lumen590of the cannula582, adjacent the distal end588. The guide member594includes a spherical body596. The spherical body596is made from, or includes, a magnetically responsive material. In particular it may be made from or include a permanent magnetic material, such as Nd—Fe—B, or a permeable magnetic material. A passage598extends through the spherical body596. A flexible sheath600, having a lumen602therethrough, extends proximally from the passage598. The sheath600may incorporate a coil or braid to prevent kinking. There may be a conical cut out in the spherical body596to accommodate the sheath600as the spherical body moves to guide a medical device, as described below.

The redirection is thus articulated, such that the orientation of the extension580relative to the cannula552can be adjusted, and the orientation of a medical device leaving the distal end of the cannula582can be adjusted. The orientation of the extension580relative to the cannula552is adjusted by moving the spherical body566, and the orientation of the medical device relative to the cannula582is adjusted by moving the spherical body596. The spherical bodies566and596are magnetically responsive and can be moved by the application of a magnetic field. This application of a magnetic field can be accomplished with a magnet system comprising one or more electromagnets and/or permanent magnets. Preferably, however, this is accomplished with one or more electromagnetic coils in the cannulas552and582. Coils (like the coils524,525, and528in device500) can be provided in the distal end of cannula552, to selectively apply a magnetic field to orient the spherical body566is a desired direction. Similarly, coils (like the coils524,525, and528in device500) can be provided in the distal end of cannula582, to selectively apply a magnetic field to orient the spherical body596is a desired direction.

More specifically, three coils are embedded in the wall of the cannula552. A first coil is arranged in a plane parallel to the longitudinal axis of the cannula, and has leads extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. A second coil is arranged in a plane parallel to the longitudinal axis of the cannula, and perpendicular to the plane of the first coil, and has leads extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. A third coil is arranged in a plane perpendicular to the longitudinal axis of the cannula, and has leads extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. By selectively connecting the coils to a power source, a magnetic field can be created in the vicinity of the spherical body556to orient the body in a selected direction. Similarly, Three coils are embedded in the wall of the cannula582. A first coil is arranged in a plane parallel to the longitudinal axis of the cannula, and has leads extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. A second coil is arranged in a plane parallel to the longitudinal axis of the cannula, and perpendicular to the plane of the first coil, and has leads extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. A third coil is arranged in a plane perpendicular to the longitudinal axis of the cannula, and has leads extending therefrom so that the coil can be selectively connected to a power source to create a magnetic field. By selectively connecting the coils to a power source, a magnetic field can be created in the vicinity of the spherical body596to orient the body in a selected direction.

An interface can be provided to allow the physician to select the direction in which to orient the extension580and to select the direction to direct the medical device from the end of the extension580, and energize the coils to apply the appropriate magnetic field to orient the spherical body566and extension580, and to orient the spherical body596, in the proper directions. A medical device can then be advanced through the device550. Lock mechanisms can secure the guide members564and594in their selected orientations. The redirection device550can be used in automatically deploying devices. An interface can receive the physician's input on a direction and/or destination, control the coils to orient the guide member564and594in the proper directions, and control an advancer to automatically advance the medical device through the guide in the proper direction, for the proper distance.

Various radioopaque patterns can be incorporated into the guides, so that the position and/or orientation of the guide can be seen on x-ray or fluoroscopic images. Examples of these patters are shown inFIGS. 31A-31E.

Imaging can also be incorporated into redirection devices of the various embodiments of the present invention. As shown inFIG. 32, an optical fiber can be incorporated into a wall of a device, with the distal end positioned at the distal end of the device to provide an image from the distal end of the device useful in operating the redirection device. As shown inFIG. 33, an optical fiber can be incorporated into the medical device being deployed from the redirection device to provide an image from the direction in which the medical device is actually traveling. As shown inFIG. 34, multiple optical fibers can be incorporated into a wall of a device, with the distal ends positioned at the distal end of the device to provide an image from the distal end of the device useful in operating the redirection device. The multiple optical fibers allow for separate illumination and/or allow for stereoscopic imaging. As shown inFIG. 35, an optical fiber can be incorporated into the wall of the redirection device such that it projects from the distal end to a position more closely adjacent where the medical device exists the redirection device.