Guiding Tube for Stimulation Leads

Abstract

The present invention relates to a guiding tube for stimulation leads, comprising a longitudinal, dimensionally stable tubular body enclosing an inner channel adapted to receive a stimulation lead, wherein at least one section of an otherwise electrically insulated inner surface of the tubular body has electroconductive properties. The present invention further relates to a corresponding stimulation lead placing system comprising such guiding tube, and to a corresponding computer program for placing a stimulation lead, utilizing such guiding tube.

Claims

1. A guiding tube for stimulation leads, comprising: a longitudinal, dimensionally stable tubular body encompassing an inner channel adapted to receive a stimulation lead; wherein at least one section of an otherwise electrically insulated inner surface of the tubular body has electroconductive properties.

2. The guiding tube according to claim 1, wherein at least one section has an open, non-circular cross section in a plane perpendicular to the longitudinal axis of the tubular body.

3. The guiding tube according to claim 1, wherein at least one section extends at least partially in a direction substantially parallel to the longitudinal axis of the tubular body.

4. The guiding tube according to claim 1, wherein at least one section has a longitudinal shape.

5. The guiding tube according to claim 1, further comprising at least one tracking marker coupled to the tubular body, the at least one tracking marker being adapted to be identified by a medical tracking system.

6. The guiding tube according to claim 1, further comprising an interface having an electroconductive interconnection to the at least one electroconductive section.

7. The guiding tube according to claim 1, wherein the guiding tube is adapted to be advanced through body tissue.

8. The guiding tube according to claim 1, wherein the guiding tube has in at least one lengthwise portion a rotationally asymmetric cross-section.

9. The guiding tube according to claim 1, wherein the guiding tube has a proximal interface section adapted to engage a correspondingly formed interface of a spatially fixed support structure, thereby providing an interlock between the guiding tube and the spatially fixed support structure.

10. A non-transitory computer readable storage medium on which a program is stored, which, when executed by at least one processor, causes the at least one processor to perform the steps of: acquiring guiding tube position data describing the spatial position of a guiding tube, the guiding tube comprising a longitudinal, dimensionally stable tubular body encompassing an inner channel adapted to receive a stimulation lead; acquiring contact data describing whether at least one directional electrode of the stimulation lead contacts at least one electroconductive section of the guiding tube; and determining, based on said guiding tube position data and said contact data, electrode position data describing the spatial position of the at least one directional electrode.

11. A stimulation lead placing system comprising: a guiding tube comprising a longitudinal, dimensionally stable tubular body encompassing an inner channel adapted to receive a stimulation lead; a stimulation lead adapted to be inserted into the inner channel of the guiding tube; wherein an outer diameter of the stimulation lead conforms to the inner diameter of the tubular body, enabling at least one electrode of the stimulation lead inserted into the inner channel to contact at least one electroconductive section of the guiding tube.

12. The stimulation lead placing system according to claim 11, wherein the stimulation lead comprises at least two directional electrodes, and wherein the at least one electroconductive section is adapted to short at least two electrodes.

13. The stimulation lead placing system according to claim 11, further comprising a readout unit which is connected to an interface of the guiding tube, the readout unit being adapted to determine whether at least one electrode of the stimulation lead contacts the at least one electroconductive section of the guiding tube.

14. The stimulation lead placing system according to claim 11, wherein the guiding tube and the stimulation lead have complementary rotationally asymmetric cross-sections in at least one lengthwise portion, allowing the stimulation lead to be placed within the guiding tube in a limited number of dedicated positions only.

15. The stimulation lead placing system according to claim 14, wherein the limited number of dedicated positions is one single position only.

16. The stimulation lead placing system according to claim 11, wherein the stimulation lead, when being placed in the guiding tube, protrudes from the distal end of the guiding tube.

17. The stimulation lead placing system according to claim 16, wherein at least one electrode placed at the distal end of the stimulation lead is not covered by tubular body.

18. The stimulation lead placing system according to claim 11, further comprising: a non-transitory computer readable storage medium on which a program is stored, which, when executed by at least one processor, causes the at least one processor to: acquire guiding tube position data describing the spatial position of the guiding tube; acquire contact data describing whether the at least one electrode of the stimulation lead contacts the at least one electroconductive section of the guiding tube; and determine, based on said guiding tube position data and said contact data, electrode position data describing the spatial position of the at least one directional electrode.

19. The stimulation lead placing system according to claim 11, further comprising: a computer including at least one processor that executes instructions stored on a computer readable storage medium to: acquire guiding tube position data describing the spatial position of the guiding tube; acquire contact data describing whether the at least one electrode of the stimulation lead contacts the at least one electroconductive section of the guiding tube; and determine, based on said guiding tube position data and said contact data, electrode position data describing the spatial position of the at least one directional electrode.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0054] In the following, the invention is described with reference to the enclosed Figures which represent preferred embodiments of the invention. The scope of the invention is not however limited to the specific features disclosed in the Figures, which show:

[0055] FIG. 1 a first embodiment of a guiding tube and a corresponding stimulation lead;

[0056] FIG. 2 a second embodiment of a guiding tube and a corresponding stimulation lead;

[0057] FIG. 3 a third embodiment of a guiding tube and a corresponding stimulation lead; and

[0058] FIG. 4 a detailed view on the proximal end of the guiding tube shown in FIG. 3.

DETAILED DESCRIPTION

[0059] FIG. 1 shows a first embodiment of the inventive guiding tube 1 which comprises a tubular body 2 and an electroconductive section 5 provided at the inner surface 6 of the tubular body 2. The body 2 encompasses a circular channel 3 having an inner diameter D, into which a stimulation lead 4 can be placed. The stimulation lead 4 has a circular cross-sectional shape having an outer diameter d that corresponds to the shape of the channel 3 of the guiding tube. This ensures that the electrodes 11 provided at the outer surface of the stimulation lead 4 contact the electroconductive section 5 as soon as the electrodes 11 reach the electroconductive section 5 which is provided at the inner surface 6. Apart from section 5, the inner surface 6 of the tubular body 2 is non-conductive. It becomes apparent from FIG. 1 that the longitudinal section 5 extending parallel to the longitudinal axis of the tubular body 2 is about to short electrodes 11 which are arranged in a longitudinal direction of the stimulation lead 4.

[0060] FIG. 2 shows a guiding tube 1 which mostly resembles the guiding tube shown in FIG. 1, but comprises an electroconductive section 5 which has a spiral shape. Further, the electroconductive section 5 is connected to an interface 10, so that an electroconductive circuit including the lead supply lines for the electrodes 11, electrode 11, section 5 and interface 10 is closed as soon as at least one of the electrodes 11 contacts section 5.

[0061] An impedance measurement on the electrodes 11 immediately indicates when at least one of the electrodes 11 of the lead 4 shown in FIG. 2 or at least two of the electrodes 11 of the lead 4 shown in FIG. 1 contact section 5, so that the position of the stimulation lead 4 and therefore also the position of the electrodes 11 can be calculated with respect to the guiding tube 1. Since the spatial position of the guiding tube 1 is determined with the help of the camera array 8 of a medical navigation system detecting the marker array 7 attached to the proximate end of the guiding tube 2 and detected by, the spatial position of the stimulation lead 4 and of each of the electrodes 11 can be calculated.

[0062] FIG. 3 shows a further embodiment of the inventive guiding tube 1. The inner channel 3 of the guiding tube has an asymmetric cross-sectional shape with four bulges, three of the bulges being identical, wherein the fourth bulge has a different shape. This will allow the stimulation lead 4 to be placed within the guiding tube 1 with one specific orientation only. The guiding tube 1 further comprises a disk-shaped interface section 13 provided at its proximal end, which can be grasped by a person so as to rotate the guiding tube 1 around the central longitudinal axis of the guiding tube 1. The form fit provided by the mating asymmetric cross-sectional shapes of channel 3 and the stimulation lead 4 rotationally holds the stimulation lead 4 in place while the guiding tube 2 is being turned. For holding the stimulation lead 4 in place, it is not even necessary for the inner channel 3 or the stimulation lead 4 to have an asymmetric cross-sectional shape over their entire length, as this is shown in the left cross-sectional view shown in FIG. 34. As shown in the right cross-sectional view in FIG. 3, it is rather sufficient to provide at least one lengthwise portion 14, preferably at the distal end of the guiding tube 1, and a corresponding lengthwise portion 15, preferably at the distal end of the stimulation lead 4, for holding the stimulation lead 4 in place.

[0063] FIG. 3 further shows that the stimulation lead 4 together with the electrodes 11 protrudes from the distal end of the tubular body 2 when being placed within the guiding tube 1.

[0064] FIG. 4 shows in detail the proximal end of the guiding tube 1 together with a corresponding interface assigned to a support structure such as a stereotactic arc. At the proximal end of the guiding tube 1, a disc-shaped interface section 13 is integrally formed with the tubular body 2, which comprises at its downward facing side a ridge. A corresponding disc that may be rigidly attached to a stereotactic arc has one central hole the tubular body 2 is placed through, and several receptacles arranged at the disc's circumference, which are to receive the ridge of disc 13. As long as disc 13 is spaced from the corresponding disc attached to the support structure (as shown in the lower right depiction in FIG. 4) the guiding tube can be rotated with respect to the stereotactic arc. As soon as a desired rotational orientation of the guiding tube has been reached, the rotational alignment of the guiding tube is fixed by snap-fitting disc 13 onto the corresponding disc of the stereotactic arc by pushing the tubular body 2 through the corresponding opening of the disc of the stereotactic arc so that the ridge engages one of the receptacles, thereby maintaining the rotational orientation of the guiding tube 1 and the stimulation lead 4 placed therein.