Medical instrument for tissue ablation by means of an HF electrode with the function of a controlled distal angular orientation

Patent metadata

Field	Value
Publication number	US-11266462-B2
Application number	US-201816117187-A
Country	US
Kind code	B2
Filing date	Aug 30, 2018
Priority date	Sep 5, 2017
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

The disclosure relates to a medical instrument for minimally invasive tissue ablation by means of an HF electrode, with a hollow shaft, wherein the HF electrode is electrically insulated from the hollow shaft, is arranged at a distal end of the latter and, in order to ablate tissue, protrudes axially beyond the hollow shaft at least in part. The angle orientation of the HF electrode relative to the hollow shaft is adjustable in a controlled manner to a working position in which the HF electrode, protrudes radially beyond an outer circumference of the hollow shaft in order to ablate tissue. In the working position, by means of suitable adjustment of the shaft and of the HF electrode, a position can always be found in which the distal end of the HF electrode sufficiently reaches or touches tissue portions that are to be ablated in the region of the bladder neck.

First claim

We claim:

1. Medical instrument for minimally invasive tissue ablation by means of an HF electrode, with a hollow shaft having a mid-line (M), wherein;
the HF electrode is electrically insulated from the hollow shaft, is arranged at a distal end of the hollow shaft and, in order to ablate tissue, protrudes axially beyond the hollow shaft at least in part;
wherein the distal end of the HF electrode is formed by a lateral ablation edge which merges, via symmetrically curved ablation edge, into a connection portion;
an angle orientation of the HF electrode relative to the hollow shaft is adjustable in a controlled manner to a fully extended working position in which the HF electrode protrudes radially beyond an outer circumference of the hollow shaft in order to ablate tissue;
wherein the lateral ablation edge intersects the mid-line (M) in the working position; and
during an axial adjustment of the connection portion of the HF electrode in the working position, the angle orientation of the curved ablation edge of the HF electrode is modified.

2. Medical instrument according to claim 1 , wherein the HF electrode has an electrical insulation channel and an HF coil, wherein
the insulation channel electrically insulates the HF electrode from the hollow shaft and protrudes axially beyond a distal end of the shaft, and
a distal end of the HF coil protrudes axially beyond the distal end of the insulation channel in order to ablate tissue.

3. Medical instrument according to claim 2 , wherein the angle orientation of the connection portion relative to the mid-line (M) of the hollow shaft is adjustable in a controlled manner in order to adjust in a controlled manner the angle orientation of the HF coil relative to the hollow shaft.

4. Medical instrument according to claim 3 , wherein the connection portion is made of a flexible or elastic, electrically conductive material, and the angle orientation of the HF coil relative to the hollow shaft is adjustable in a controlled manner by bending or kinking of the connection portion.

5. Medical instrument according to claim 4 , wherein the HF electrode is elastically prestressed to the working position, in which a distal end of the connection portion is bent or kinked relative to a proximal end of the connection portion in order to enclose an acute angle with a mid-line (M) of the hollow shaft.

6. Medical instrument according to claim 1 , further comprising an adjustable angling element, wherein the angle orientation of the HF electrode relative to the hollow shaft is adjustable in a controlled manner by adjustment of the angling element in contact with a portion of the HF electrode or of the electrical insulation channel.

7. Medical instrument according to claim 6 , wherein the angling element is a piezoelectric element, or a thermally adjustable element, or a mechanically adjustable element.

8. Medical instrument according to claim 3 , wherein the HF electrode has hinges which are arranged on the connection portion, such that the angle orientation of the HF coil relative to the hollow shaft is adjustable in a controlled manner by adjustment of the hinges.

9. Medical instrument according to claim 8 , further comprising a pulling or pushing rod which is coupled to the HF coil such that an adjustment of the pulling or pushing rod causes an adjustment of the angle orientation of the HF coil relative to the hollow shaft.

10. Medical instrument according to claim 8 , wherein elastic restoring means are assigned to the hinges in order to elastically prestress the HF coil to a rectilinear or angled rest position.

11. Medical instrument according to claim 1 , wherein the HF electrode is formed at least in part from a memory metal, which is configured such that the angle orientation of the HF electrode relative to the hollow shaft is adjustable in a controlled manner, in particular by application of an electric current or by a temperature change.

12. Medical instrument according to claim 1 , wherein the hollow shaft has a hollow outer shaft and an inner shaft received therein, wherein the inner shaft is guided longitudinally displaceably in the hollow outer shaft, and wherein the HF electrode can be retracted completely into the hollow outer shaft.

13. Medical instrument according to claim 1 , wherein an angle of inclination of the HF electrode relative to a mid-line (M) of the hollow shaft is adjustable by up to 90°.

14. Medical instrument according to claim 1 , wherein the lateral ablation edge comprises a first material, wherein the connection portion comprises a second material, and wherein the first material is less flexible than the second material.

Assignees

• Storz Karl Se & Co Kg

Inventors

• Löffler Oliver
• Rehbein Stefan
• Wittke Uwe
• Doll Frank
• Hermle Rainer
• Nagele Udo

Classifications

• A61B18/1485 Primary

  having a short rigid shaft for accessing the inner body through natural openings · CPC title

• A61B2018/00601

  Cutting · CPC title

• A61B2017/00274

  Prostate operation, e.g. prostatectomy, turp, bhp treatment · CPC title

• A61B2018/1475

  Electrodes retractable in or deployable from a housing · CPC title

• A61B2018/00196

  reciprocating lengthwise · CPC title