U.S. patent application number 14/181553 was filed with the patent office on 2014-06-12 for anti-seeding arrangement.
This patent application is currently assigned to NEODYNAMICS AB. The applicant listed for this patent is NEODYNAMICS AB. Invention is credited to Gert Auer, Vilhelm Ekstrand, Hans Wiksell.
Application Number | 20140163544 14/181553 |
Document ID | / |
Family ID | 36778377 |
Filed Date | 2014-06-12 |
United States Patent
Application |
20140163544 |
Kind Code |
A1 |
Wiksell; Hans ; et
al. |
June 12, 2014 |
ANTI-SEEDING ARRANGEMENT
Abstract
The present invention relates to an anti-seeding arrangement
(100) for invasive treatment of a human or animal body comprising
an elongated hollow member (102), and a first electrode (116) of
which one portion is arranged near one end of the elongated hollow
member (102), said first electrode (116) being connectable to an
electromagnetic field generator (110), wherein the elongated hollow
member (102) is arranged to be inserted into the human or animal
body, control means (106, 108) arranged to control the
electromagnetic field generator (110) for delivering radio
frequency bursts to the first electrode (116), and sensing means
(104) to sense a physical property dependent on the insertion
length of the elongated hollow member (102) in the human or animal
body, and wherein the control means (106, 108) is arranged to
control the operation of the electromagnetic field generator (110)
in dependence of the sensed physical property.
Inventors: |
Wiksell; Hans; (Taby,
SE) ; Auer; Gert; (Solna, SE) ; Ekstrand;
Vilhelm; (Voorburg, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NEODYNAMICS AB |
Lidingo |
|
SE |
|
|
Assignee: |
NEODYNAMICS AB
Lidingo
SE
|
Family ID: |
36778377 |
Appl. No.: |
14/181553 |
Filed: |
February 14, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12294671 |
Dec 8, 2008 |
8652124 |
|
|
PCT/EP2007/052058 |
Mar 5, 2007 |
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14181553 |
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Current U.S.
Class: |
606/33 |
Current CPC
Class: |
A61B 2018/0019 20130101;
A61B 2018/00083 20130101; A61B 34/20 20160201; A61B 2018/1467
20130101; A61B 18/1477 20130101; A61B 18/1206 20130101; A61B
2018/00196 20130101; A61B 10/0233 20130101; A61B 2018/00875
20130101 |
Class at
Publication: |
606/33 |
International
Class: |
A61B 18/14 20060101
A61B018/14; A61B 18/12 20060101 A61B018/12 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 28, 2006 |
EP |
06006361.7 |
Claims
1-21. (canceled)
22. An arrangement adapted to avoid seeding infectious cells during
invasive medical procedures on a human body or an animal body, the
arrangement comprising: an electromagnetic field generator; an
elongated hollow member having two ends and an electrode, the
electrode positioned such that one portion of the electrode is at
one of the two ends of the elongated hollow member, the electrode
being connected to the electromagnetic field generator, the
elongated hollow member being configured to be inserted into a
human body or an animal body; a sensing unit configured to sense a
penetration depth of the elongated hollow member in tissue; and a
control unit arranged to control the electromagnetic field
generator so as to deliver radio frequency ("RF") energy bursts to
the electrode and being arranged to receive the sensed penetration
depth from the sensing unit and control the electromagnetic field
generator in dependence on the sensed penetration depth and
comprising a triggering unit arranged to trigger the
electromagnetic field generator to deliver RF energy bursts in
dependence on variations of the sensed penetration depth of the
elongated hollow member.
23. The arrangement according to claim 22, wherein the elongated
hollow member comprises a region that is electrically insulated in
relation to the electrode.
24. The arrangement according to claim 23, wherein the insulated
region comprises a hollow insulating sheath being longitudinally
movable along the elongated hollow member over the electrode,
whereby the effective length of the electrode can be varied without
moving the elongated hollow member longitudinally.
25. The arrangement according to claim 23, wherein the insulating
region comprises a hollow insulating sheath being longitudinally
movable along the elongated hollow member over the electrode, the
hollow insulating sheath having a first part arranged to be
insertable in tissue surrounding the electrode, and a second part
arranged to hinder further penetration of the second part into
tissue, the second part comprising a flange.
26. The arrangement according to claim 22, wherein the electrode is
longitudinally segmented with each segment individually controlled
by the control unit wherein the control unit is arranged to control
the triggering unit to trigger the electromagnetic field generator
to deliver bursts of radio frequency (RF) energy to selected
segments of the electrode, wherein a segment of the electrode that
is positioned at an air-skin interface of the elongated hollow
member can be deactivated whereby skin burn effects can be
avoided.
27. The arrangement according to claim 22, wherein the elongated
hollow member comprises a plurality of electrodes each of which is
individually controllable by the control means wherein the control
means is arranged to control the triggering unit to trigger the
electromagnetic field generator to deliver bursts of radio
frequency (RF) energy to selected electrodes of the plurality of
electrodes of the elongated hollow member.
28. The arrangement according to claim 22, wherein the elongated
hollow member is coated with a dielectric material whereby the
frequency of operation of the electrode is limited to higher
frequencies.
29. The arrangement according to claim 22, wherein the control
means is further arranged to automatically control the triggering
unit to trigger the electromagnetic field generator to deliver
bursts of radio frequency (RF) energy to the electrode of the
elongated hollow member when the sensing unit determines that
movement of the elongated hollow member is occurring.
30. The arrangement according to claim 22 wherein a burst of energy
provided by the electromagnetic field generator comprises energy
having an off-duration that is several orders of magnitude larger
than an on-duration of the energy.
31. An arrangement adapted to avoid seeding infectious cells during
invasive medical procedures on a human body or an animal body, the
arrangement comprising: an electromagnetic field generator; an
elongated hollow member having two ends and an electrode, the
electrode positioned such that one portion of the electrode is at
one of the two ends of the elongated hollow member, the electrode
being connected to the electromagnetic field generator, the
elongated hollow member being configured to be inserted into a
human body or an animal body, the hollow member further comprising
a hollow insulating sheath being longitudinally movable over the
electrode to selectively surround the electrode thereby creating an
insulating region; a sensing unit configured to sense an effective
penetration depth of the elongated hollow member in tissue, the
effective penetration depth being varied in dependence on the
movement of the hollow insulating sheath along the elongated hollow
member; and a control unit arranged to receive the sensed effective
penetration depth from the sensing unit and control the
electromagnetic field generator to deliver radio frequency ("RF")
energy bursts to the electrode, and being arranged to control the
electromagnetic field generator in dependence on the sensed
penetration depth, and comprising a triggering unit arranged to
trigger the electromagnetic field generator to deliver RF energy
bursts in dependence on variations of the sensed effective
penetration depth of the elongated hollow member.
32. The arrangement according to claim 31, wherein the hollow
insulating sheath has a first part arranged to be insertable in
tissue surrounding the electrode, and a second part arranged to
hinder further penetration of the second part into tissue, the
second part comprising a flange.
33. The arrangement according to claim 31, wherein the electrode is
longitudinally segmented with each segment individually controlled
by the control unit wherein the control unit is arranged to control
the triggering unit to trigger the electromagnetic field generator
to deliver bursts of radio frequency (RF) energy to selected
segments of the electrode, wherein a segment of the electrode that
is positioned at an air-skin interface of the elongated hollow
member can be deactivated whereby skin burn effects can be
avoided.
34. The arrangement according to claim 31, wherein the elongated
hollow member comprises a plurality of electrodes each of which is
individually controllable by the control means wherein the control
means is arranged to control the triggering unit to trigger the
electromagnetic field generator to deliver bursts of radio
frequency (RF) energy to selected electrodes of the plurality of
electrodes of the elongated hollow member.
35. The arrangement according to claim 31, wherein the elongated
hollow member is coated with a dielectric material whereby the
frequency of operation of the electrode is limited to higher
frequencies.
36. The arrangement according to claim 31, wherein the control
means is further arranged to automatically control the triggering
unit to trigger the electromagnetic field generator to deliver
bursts of radio frequency (RF) energy to the electrode of the
elongated hollow member when the sensing unit determines that
movement of the elongated hollow member is occurring.
37. The arrangement according to claim 31 wherein a burst of energy
provided by the electromagnetic field generator comprises energy
having an off-duration that is several orders of magnitude larger
than an on-duration of the energy.
38. A method for avoiding the seeding of infectious cells during an
invasive medical procedure on a human body or an animal body, the
method comprising: sensing a penetration depth in tissue of an
elongated hollow member having two ends and an electrode, the
electrode positioned such that one portion of the electrode is at
one of the two ends of the elongated hollow member, the electrode
being connected to an electromagnetic field generator; and
controlling the electromagnetic field generator to deliver radio
frequency ("RF") energy bursts to the electrode in dependence on
the sensed penetration depth of the hollow member and triggering
the electromagnetic field generator to deliver RF energy bursts in
dependence on variations of the sensed penetration depth of the
elongated hollow member.
39. The method according to claim 38, further comprising the step
of moving longitudinally a hollow insulating sheath along the
elongated hollow member over the electrode wherein the elongated
hollow member comprises a region that is electrically insulated in
relation to the electrode, and whereby the effective length of the
electrode can be varied without moving the elongated hollow member
longitudinally.
40. The method according to claim 39, further comprising the step
of hindering insertion of the second part of the hollow sheath
member into tissue by means of a flange associated with a second
part of the hollow member.
41. The method according to claim 38, wherein the step of sensing
further comprises sensing a penetration depth in tissue of an
elongated hollow member having a segmented electrode; and the step
of controlling further comprises triggering the electromagnetic
field generator to deliver bursts of radio frequency (RF) energy to
selected segments of the electrode, wherein a segment of the
electrode that is positioned at an air-skin interface of the
elongated hollow member can be deactivated whereby skin burn
effects can be avoided.
42. The method according to claim 38, wherein the step of sensing
further comprises sensing a penetration depth in tissue of an
elongated hollow member having a plurality of electrodes; and the
step of controlling further comprises triggering the
electromagnetic field generator to deliver bursts of radio
frequency (RF) energy to selected electrodes of the plurality of
electrodes located in the elongated hollow member, wherein each of
the electrodes is individually controllable.
43. The method according to claim 38, wherein the step of
controlling further comprises automatically triggering the
electromagnetic field generator to deliver bursts of radio
frequency (RF) energy to the electrode of the elongated hollow
member upon sensing that movement of the elongated hollow member is
occurring.
44. The method according to claim 38, wherein the step of
controlling further comprises controlling the electromagnetic field
generator to deliver radio frequency ("RF") energy bursts having an
off-duration that is several orders of magnitude larger than an
on-duration of the energy.
Description
[0001] The present invention relates in general to providing an
arrangement for invasive operations in human or animal bodies, and
especially to providing an arrangement for anti-seeding in
connection to invasive operations in human or animal bodies.
DESCRIPTION OF RELATED ART
[0002] Many people in the western world face the prospect of
cancer. The most common cancer forms in females and males are
breast cancer and prostatic cancer, respectively.
[0003] A successful cancer therapy is often dependent on a high
quality tumour diagnosis. There are today two major methods of
morphological diagnosis. These are histopathological examination of
surgical biopsies or core biopsies and cytopathological examination
of fine needle aspirates.
[0004] In core biopsy, a tissue sample is removed from the lesion,
for example by using a coarse core biopsy needle. This tissue
sample is then examined histologically.
[0005] In cytological diagnosis, a suspension of cells is aspirated
from the lesion with the aid of a fine needle. Since the adhesion
between tumour cells is lower than the adhesion between healthy
cells, tumour cells are enriched in the aspirate. Ongoing advances
suggest that completely objective molecular diagnostic procedures
on single cells from fine needle aspirates can be available in the
near future.
[0006] Applying modern diagnosis, small tumours can be detected
which have not yet metastased. For such cancer tumours, having an
extension that typically is less than 10 mm, conventional surgery
may be seen as too coarse a method.
[0007] Also, in therapy the tendency has been towards less invasive
local treatment of the tumour and hence away from radical surgery
such as mastectomy, in the breast cancer case. The goal of radical
mastectomy is to remove all malignant tissue, which combined with
lymph node resection, often results in considerable
hospitalisation.
[0008] Minimally invasive approaches, in contrast to open surgery,
have as potential benefits reduced morbidity rates, reduced
treatment duration and provide the possibility to treat a patient
in a weak medical condition.
[0009] One example of a minimally invasive therapy approach is the
radio frequency ablation (RFA) technique which uses radio frequency
energy to cause thermal destruction of tumour cells. The
destruction can be obtained by, for example, inserting a needle
directly in the tumour, arranging a large counter electrode to an
outer surface of the body and applying radio frequency energy
between the needle and the counter electrode. The high current
density at the needle generates heat in the tissue, causing thermal
destruction and/or denaturation of said tissue.
[0010] At present the RFA technique is most often viewed as being
palliative and used to shrink the tumours such that surgery can be
avoided.
[0011] Another minimally invasive approach is stereo tactic
excision or large core biopsy, which is a surgical technique that
preferably involves removing the entire breast lesion under image
guidance. By using large core biopsy, breast tissue of the size of
5 mm to 20 mm may be removed. This procedure also allows the
radiologist or surgeon to remove the entire lesion in one
non-fragmented piece. The core specimen of the breast tissue is
often removed with a looped wire and taken to the pathology
laboratory for diagnosis.
[0012] Yet another minimally invasive approach that can be applied
in diagnosis and therapy of body tissue is infusion of diagnostic
and therapeutic agents to a site within a tissue. By inserting a
needle reaching an invasive site, and presenting the needle tip to
the tissue site, a site-specific delivery of diagnostic and
therapeutic agents to said tissue site is enabled.
[0013] Yet other minimally invasive techniques that may be used for
the same or similar purposes are endoscopic procedures, wherein
tubular devices are percutaneously inserted in a body to reach an
invasive site in need for surgical operation or investigation. In
short, tissue may hence be resected, visually examined and sampled
without open surgery.
[0014] The techniques and methods for diagnosis and/or therapy of
tissue as mentioned above have the common denominator of involving
a touching or puncturing malignant tissue by at least one part of
the device being used.
[0015] In addition, said techniques and methods may also touch or
puncture local infections.
[0016] By puncturing and/or manipulating malignant tissue, cancer
cells can be disrupted from their original position and deposed in
other places.
[0017] Disruption and disposition of cancer cells may further give
rise to seeding of cancer cells in the tract formed by the
equipment being used, considered that some part, for instance the
distal end of a needle, of the equipment penetrates or contacts the
malignant tissue. Upon penetration or contacting by the distal end
of malignant tissue, said distal end becomes contaminated with
non-healthy cells. Upon removal of the equipment, the contaminated
distal end is slid along the tract/channel that was formed upon
insertion, malignant tissue cells may come loose from the
contaminated distal end or the malignant tissue as such and may be
repositioned onto the walls of the tract/channel, thereby causing
the seeding of the tumour.
[0018] This seeding of cancer cells may give rise to new cancer
tumours.
[0019] Tumour seeding may thus be result of core biopsy,
laparoscopy, radio frequency ablation, injection, and fine needle
aspiration or punctuation etc. and can therefore negate the
benefits of the operation involved.
[0020] For obvious reasons, seeding of local infectious matter may
also occur during the above operations. This is of special
importance during trans-rectal procedures of for example the
prostate.
[0021] In the following, prior art documents related to potential
spread of un-healthy cells are presented.
[0022] From US 2004/0186422 A1 a needle for delivering therapeutic
or diagnostic agents in a target site in a body is known. The
needle may be provided with an electrode that is coupled to a radio
frequency generator. By delivering electrical energy from at least
a portion of the needle to tissue surrounding at least a portion of
the tract, the surrounding tissue may coagulate, be ablated or
otherwise treat the surrounding tissue to substantially seal or
occlude the tract. Electrical energy may be delivered to additional
tissue along the tract in short bursts such that spaced-apart
regions can be treated. Alternatively, energy is delivered
substantially continuously upon withdrawal of the needle to
substantially seal the tract along its entire length. The tract may
thus be substantially sealed lowering the risk of tracking seeding
from a tumour and/or contaminating tissue surrounding a target
region to which an agent is delivered.
[0023] One disadvantageous property of this technique is that the
delivered radio frequency energy heats the tissue surrounding the
track such that tissue of a relatively large depth is affected by
the high temperature produced.
[0024] Another disadvantage of the diagnostic equipment of this
technique is that sample tissue in the needle is also affected by
the heating caused by the radio frequency energy.
[0025] A potential disadvantage of the technique of US 2004/0186422
A1 is associated with the application of the short bursts or
continuous radio frequency energy to substantially seal the track
when the needle or instrument is being retracted. Since the
technique is operated manually and the needle is typically held and
retracted by an operator, there is a risk that viable cells will
remain in the track after the application of the radio frequency
energy when retracting the needle, since the result of treating the
tract is dependent of the skill of the operator using this
technique.
[0026] Another potential disadvantage with the regime of US
2004/0186422 A1 is there is no solution to disruption of tumour
cells when the inserted instrument penetrates through the tumour,
potentially leading to seeding of tumour cells.
[0027] In addition, since the technique is operated manually, the
technique is time consuming in general and consumes time for an
operator in particular, which are disadvantageous.
[0028] From US 2003/0195500 it is known a modular biopsy ablation
or track coagulation needle comprising an outer tubular member and
an inner member which allows a biopsy needle to be inserted into,
and coaxially engaged with, a delivery needle and removed when not
needed. It also allows to more efficiently biopsy a tumour, ablate
it and coagulate the track by ablation while reducing the track
seeding and blood loss. The ablation needle and biopsy needle forms
a connector arranged to be coupled to an electric ablating
source.
[0029] In the case of track ablation, an isotherm of 48.degree. C.
is suggested which extends 1 mm radially from the track into the
tissue. In the case of tumour ablation the isotherm of 48.degree.
C. is suggested to have a radical extension of 20 mm, which is
being achieved by using a higher microwave power or a different
microwave frequency, as compared to the track ablation case.
[0030] A clear disadvantage with the technique as disclosed by US
2003/0195500 is that this device uses microwave frequency energy. A
consequence of using microwave frequencies is that a comparatively
large tissue region is heated, where said region also comprises
healthy tissue in no need of treatment, which clearly is
non-beneficial.
[0031] Another disadvantage of the US 2003/0195500 technique is
that coagulation of the entire track requires multiple applications
of micro-wave energy, where the delivery needle is rejected
piece-wise, and where microwave frequencies are applied to the
delivery needle in between the rejections, due to the fact that
each application of the microwave energy of the power being used to
achieve the isotherms as mentioned above, lasts a relatively long
time.
[0032] Moreover, manual operation of this regime brings the
disadvantage of risking that viable cells remain in the track
subsequent to the application of micro-wave energy, since the
tissue surrounding the track is often non-homogenous and therefore
require different applications of energy to ablate the track.
[0033] Yet another disadvantage is that energy absorption upon
application of microwave frequency is often non-homogenous, which
can result in spots being over-heated, so called "hot spots".
[0034] From U.S. Pat. No. 6,126,216 it is known a medical
instrument comprising a cannula or probe that is used to penetrate
tissue to a target area to be used in medical procedures including
biopsy and radio frequency ablation of undesirable tissues or cells
for treatment of or to prevent the spread of cancer cells during a
biopsy procedure.
[0035] The exterior surface of the probe has a dielectric coating,
and control means for adjusting the electric current to the
cannula, a radio frequency generator and a return electrode. By
generating radio frequency energy, the cannula is heated above a
critical temperature causing the tissue surrounding the cannula to
become non-viable.
[0036] The disclosure of U.S. Pat. No. 6,126,216 comprises a first
application being a biopsy needle, for which ablative radio
frequency energy is claimed to be delivered to the tissue to
provide resistive heating approximately 10 cell layers deep around
the cannula. No information is provided to support this cell layer
performance.
[0037] One drawback with the biopsy needle technique as disclosed
in U.S. Pat. No. 6,126,216 is the application of radio frequency
energy which is applied to achieve elevated temperature in tissue
of a depth of approximately 10 cell layers.
[0038] To our understanding, the radio frequency energy is applied
by applying a current having a very low current density in order to
restrict the temperature rise to a depth of approximately 10 cell
layers. Using a low current density however requires a long
duration of application of the radio frequency energy, which for
this reason is a clear drawback since the rise in temperature
during that duration will be influenced by heat conduction to
neighbouring tissues and thereby also by blood perfusion and other
tissue properties.
[0039] Another drawback of the technique as disclosed by U.S. Pat.
No. 6,126,216 is the skin burn effect that is caused due to the
contact between the electrode and the skin upon penetrating the
skin by the biopsy needle, upon application of radio frequency
energy to the biopsy needle. The usage of the entire shaft of the
needle as an electrode thus results in undesired skin burn
effects.
[0040] A potential drawback of the technique of U.S. Pat. No.
6,126,216 is that full penetration of a tumour by the electrode may
result in dislocated viable tumour cells that could proliferate in
healthy tissue into new cancer tumours.
[0041] Conclusively, a common disadvantage of the prior art
techniques and disclosures is that movement of inserted instruments
in longitudinal directions may result in non-complete track tumour
cell killing.
[0042] In addition, continuous application of energy may result in
an unnecessarily large diameter of tissue killing that the sample
in the needle is affected as well as an increased operation
time.
[0043] There is thus a need for providing a more efficient
anti-seeding device free from the disadvantages and drawbacks that
are associated with the prior art techniques.
SUMMARY OF THE INVENTION
[0044] It is an object of the present invention to provide an
anti-seeding arrangement enabling a complete anti-seeding
treatment.
[0045] According to one aspect of this invention, this object is
achieved by the arrangement for invasive treatment of a human or
animal body comprising
an elongated hollow member having two ends, and a first electrode
of which at least one portion is arranged at least near one end of
the elongated hollow member, said first electrode being connectable
to an electromagnetic field generator, wherein the elongated hollow
member is arranged to be at least partly inserted into the human or
animal body, sensing means arranged to sense a physical property of
the arrangement, which physical property is being dependent on at
least of the insertion length of the elongated hollow member in the
human or animal body, and control means arranged to control the
electromagnetic field generator for delivering radio frequency
bursts to the first electrode of the elongated hollow member, being
connectable to an electromagnetic field generator, being arranged
to control the operation of the electromagnetic field generator in
dependence of the sensed physical property by the sensing means and
comprising triggering means for triggering the electromagnetic
field generator to deliver radio frequency bursts in dependence of
variations of the sensed physical property.
[0046] A second aspect of the present invention is directed towards
the arrangement for invasive treatment including the features of
the first aspect, wherein the sensing means is arranged to sense
the physical property optically, mechanically, acoustically,
electrically or electromagnetically.
[0047] A third aspect of the present invention is directed towards
the arrangement for invasive treatment including the features of
the first aspect, wherein the sensing means comprises impedance
sensing means.
[0048] This aspect of the present invention is advantageous since
the impedance being an electrical quantity that is easily
obtainable and convenient to utilize in electrical or electronic
control means.
[0049] A fifth aspect of the present invention is directed towards
the arrangement for invasive treatment including the features of
the first aspect, further comprising a second electrode arranged to
be connected to the electromagnetic field generator and arranged to
be positioned on the human or animal body.
[0050] A sixth aspect of the present invention is directed towards
the arrangement for invasive treatment including the features of
the fifth aspect, wherein the impedance sensing means is arranged
to sense an impedance at least related to the impedance between the
second electrode and at least part of the first electrode.
[0051] This aspect of the present invention is advantageous since
the impedance between the second electrode and at least part of the
first electrode is easily measurable.
[0052] A seventh aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the sensing means is arranged
to sense the distance from a reference point for the elongated
hollow member to the surface of the tissue into which the elongated
hollow member is arranged to be at least partly inserted.
[0053] An eighth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the control means is arranged
to be connected to the sensing means.
[0054] A ninth aspect of the present invention is directed towards
the arrangement for invasive treatment including the features of
the first aspect, wherein the control means is arranged to control
the operation of the electromagnetic field generator such that
radio frequency bursts are delivered from the electromagnetic field
generator in dependence of variations of the sensed physical
property value.
[0055] This aspect of the present invention is advantageous since
making the electromagnetic field generator deliver radio frequency
energy in dependence of the variations of the sensed physical
property enables a rapid response to movements of the elongated
hollow member.
[0056] A tenth aspect of the present invention is directed towards
the arrangement for invasive treatment including the features of
the first aspect, wherein the arrangement further comprises the
electromagnetic field generator, and wherein the electromagnetic
field generator is arranged to deliver radio frequency bursts.
[0057] An eleventh aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the first electrode is
located at one end of the elongated hollow member.
[0058] A twelfth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the elongated hollow member
comprises a region that is electrically insulated in relation to
the first electrode.
[0059] This aspect of the present invention is advantageous since
it provides protection against skin burn effects upon operation of
the arrangement of the present invention.
[0060] A thirteenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the twelfth aspect, wherein the insulating region is
situated near the other end of the elongated hollow member.
[0061] A fourteenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the thirteenth aspect, wherein the insulating region
comprises a hollow insulating sheath being longitudinally movable
over the first electrode.
[0062] This aspect of the present invention is advantageous since
the insulating sheath enables quick variation of the effective
length of the first electrode in the tissue.
[0063] A fifteenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the first electrode is
longitudinally segmented.
[0064] This aspect of the present invention is advantageous since
segmentation may provide protection against skin burn effects, as
well as enable variation of the effective length of the first
electrode.
[0065] A sixteenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the elongated hollow member
is coated with a dielectric material.
[0066] This aspect of the present invention is advantageous since
ablation by part of an elongated hollow member may be achieved at
one radio frequency and anti-seeding of the entire track may be
achieved using the same elongated hollow member at a different
frequency
[0067] A seventeenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the sixteenth aspect, wherein the radio frequency
bursts are generated at one or more radio frequencies.
[0068] An eighteenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the elongated hollow member
comprises a needle arranged for fine needle aspiration or
injection.
[0069] This aspect of the present invention is advantageous since
it provides anti-seeding to fine aspiration or injection
needles.
[0070] A nineteenth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the elongated hollow member
further comprises a solid member insertable into the hollow member,
wherein both are arranged for biopsy operations.
[0071] This aspect of the present invention is advantageous since
it provides anti-seeding to elongated hollow members used in biopsy
operations.
[0072] A twentieth aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the elongated hollow member
is arranged for radio frequency ablation of tissue of human or
animal body.
[0073] This aspect of the present invention is advantageous since
it provides anti-seeding to elongated hollow members used in
ablation.
[0074] A twenty-first aspect of the present invention is directed
towards the arrangement for invasive treatment including the
features of the first aspect, wherein the elongated hollow member
is arranged for endoscopic operations.
[0075] This aspect of the present invention is advantageous since
it provides anti-seeding to elongated hollow members used for
endoscopic operations.
[0076] The present invention has the following overall
advantages:
[0077] Application of sensing means for the detection of movement
of the elongated hollow member together with the usage of radio
frequency power creating an essentially instantaneous denaturation
of tissue surrounding an anti-seeding electrode, provides a rapid
arrangement for anti-seeding without being directed towards time
consuming alternatives as presented by the prior art. The invention
is also advantageous since the rapid response will be dependent on
the triggering of the electromagnetic field generator.
[0078] It should be emphasized that the term "comprises/comprising"
when used in this specification is taken to specify the presence of
stated features, integers, steps or components, but does not
preclude the presence or addition of one or more other features,
integers, steps, components or groups thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0079] The present invention will now be described in more detail
in relation to the enclosed drawings, in which:
[0080] FIG. 1 shows a schematical representation of an arrangement
for invasive treatment according to one embodiment of the present
invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0081] The present invention thus relates to an arrangement for
treating a human or animal body in general, and to an arrangement
for denaturating tissue, cells and infectious matter in a human or
animal body in particular.
[0082] Since seeding or spreading of malignant cells, tissue or
infectious matter is an evident risk when inserting medical
equipment into a human or animal body site containing such matter,
seeding may occur in various applications such as infusion, radio
frequency ablation, fine needle aspiration, core biopsy as well as
endoscopic procedures. For this reason and to enable a more
efficient anti-seeding procedure the anti-seeding arrangement of
the present invention is arranged to be utilized in every one of
the applications as mentioned above, that is in infusion, in radio
frequency ablation, in fine needle aspiration, in core biopsy as
well as in endoscopic procedures.
[0083] Whenever a member is passed through healthy tissue after the
management of infectious or malign tissue, it is desirable that the
member is free from contamination
[0084] With this aim radio frequency bursts are applied between a
first electrode and a counter electrode in the present
invention.
[0085] In general terms the arrangement for anti-seeding according
to the present invention comprises an elongated hollow member that
is adapted to be inserted into a tissue by puncturing the tissue
with one end of the elongated hollow member.
[0086] In addition the arrangement comprises means for sensing
longitudinal movement of the member relative to the tissue.
Moreover the arrangement also comprises means for controlling an
electromagnetic field generator such that radio frequency bursts of
a relatively high power can be applied to the tissue by the
elongated hollow member.
[0087] With reference to FIG. 1 schematically showing one
representation of the arrangement for invasive treatment according
to the present invention, the present invention will further be
explained.
[0088] The representation in FIG. 1 of the arrangement 100
comprises an elongated hollow member 102, which may be adapted to
specific applications of this invention, as will be described down
below and which further is arranged to be at least partially
inserted in a human or animal body. The arrangement 100 further
comprises sensing means 104 coupled to the elongated hollow member
102 and arranged to be used when determining the insertion length
of the elongated hollow member 102 in a human or animal body, and a
control unit 108 to which the sensing unit 104 and a user input
unit 112, are connected. The control unit 108 is further connected
to a triggering unit 106 and a radio frequency generator 110, where
the triggering unit 106 is arranged to trigger the radio frequency
generator 110 in dependence of input from the sensing unit 104 and
the user input unit 112. The radio frequency generator 110 is
further coupled to a first electrode 116 that is comprised by the
elongated hollow member 102, and to a counter electrode 114, being
one example of a second electrode.
[0089] The sensing unit 104 may be arranged to sense the impedance
between the first electrode 116 of the elongated hollow member 102
and the counter plate 114, wherein the impedance is dependent of
the insertion length of the elongated hollow member in the human or
animal body. The impedance between the first electrode of the
elongated hollow member and the counter plate typically decreases
upon increasing the penetration depth in the human or animal body.
This is due to that the contact surface between the first electrode
and the surrounding tissue when penetrating the elongated hollow
member is increased.
[0090] In an alternative embodiment of the present invention, the
sensing unit 104 is arranged to sense the penetration depth of the
elongated hollow member in the tissue, for instance the distance
from a reference point for the elongated hollow member to the
tissue surface, in a mechanical way.
[0091] In yet another embodiment of the present invention, the
sensing unit 104 may be arranged to sense the penetration depth of
the elongated hollow member in the tissue acoustically or
electromagnetically, for instance by sensing the distance from a
reference point for the elongated tubular member to the tissue
surface.
[0092] According to still yet another embodiment of the present
invention the sensing means and the control means may be integrally
formed.
[0093] It should be emphasized that the arrangement as
schematically shown in FIG. 1 is one representation of an
arrangement of the present invention. Other representations which
may comprise different units, and/or comprise units having combined
functions as compared with the representation as shown in FIG. 1,
are also envisaged.
[0094] The triggering unit 106 is thus arranged to be connected to
the radio frequency generator 110 and to generate a trigger signal
triggering the radio frequency generator to generate radio
frequency energy. Moreover, the radio frequency generator 110 is
arranged to generate radio frequency energy in the form of bursts
having a duration of the order microseconds up to milliseconds
depending on the used frequency in the bursts. The radio frequency
generator is arranged to deliver such bursts at regular intervals
having an off-duration of several orders of magnitude larger than
the on-duration, wherein the on-duration equals to the burst
length.
[0095] For this reason a relatively high power of radio frequency
energy may be applied for the purpose of anti-seeding. The power
that is applicable in each case is dependent on a number of
parameters including the diameter of the elongated hollow member to
be inserted in the tissue, the conductivity and characteristics of
the tissue into which the member is to be inserted, the blood flow
of the tissue, the shape and configuration of the electrode of the
elongated hollow member etc.
[0096] Since the power dependency of the radius, R of an electrode
is proportional to R.sup.4, large electrodes require a high power,
whereas anti-seeding using thin electrodes shows promising results
using low or moderate power levels.
[0097] It is however possible to use high power radio frequency
energy under certain circumstances, as indicated above. For
instance peak power levels up to tens of kW may be used. Again by
using an off-duration being several orders of magnitude larger than
the on-duration, high power levels may be used in special
circumstances. In general more modest power levels tailored for the
case in point are used with which rapid highly efficient
anti-seeding may be obtained.
[0098] The triggering unit 106 may be arranged to trigger the
electromagnetic generator 110 to deliver electromagnetic energy to
the first electrode, as the sensing unit senses a movement of the
elongated hollow member 102. The elongated hollow member is either
retracted manually or mechanically or may even be moved by a
combined motion under both manual and mechanical influence. The
electromagnetic energy can be delivered to the first electrode
irrespective of how the elongated hollow member is retracted.
[0099] The radio frequency bursts as applied to the first electrode
may thus be activated upon retraction of the elongated hollow
member 102. In one alternative embodiment of the present invention
the radio frequency bursts may be activated upon insertion of the
elongated hollow member in the human or animal body.
[0100] Application of bursts or short pulses when using the
arrangement 100 in relation to a lesion in a human or an animal
body, enables the control of the application of radio frequency
energy to the tissue such that the tissue region that is affected
by radio frequency energy is a few cell layers thick around the
first electrode 116.
[0101] Moreover, using sensing means for the control of the
application of high power short pulses achieves substantially
immediate tract killing enabling rapid movement of elongated hollow
members 102 in the treated tissue, with unchanged anti-seeding
performance.
[0102] Rapid and reliable tract killing or denaturation of a tissue
site under investigation is thus enabled by using an elongated
hollow member of the present invention and triggering of radio
frequency bursts or anti-seeding pulses.
[0103] In one alternative embodiment of the present invention, the
arrangement 100 may comprise means for longitudinal and/or
rotational movements of the elongated hollow member. Such means may
provide an oscillating longitudinal vibration and/or rotational
movement of the elongated hollow member, wherein the movement has a
frequency in the order of 50-500 Hz. Providing an oscillating
longitudinal and/or rotational movement of the elongated hollow
member 102 facilitates insertion of the elongated hollow member in
the human or animal body as penetration resistance of the needle
into the tumour during the insertion phase is decreased. It may
also increase the sample volume.
[0104] Triggered anti-seeding is thus also needed during each
vibrational retraction and insertion phase.
[0105] In addition to the advantage of denaturation possible cancer
cells in the track caused upon insertion of the elongated hollow
member, application of radio frequency energy brings the advantage
of stopping potential bleeding from the lesion caused by the
elongated hollow member.
[0106] In the following will the elongated hollow member be
explained in more detail.
[0107] The elongated hollow member 102 typically has first and a
second end. Upon usage of the elongated hollow member 102, that is
for instance inserting the elongated hollow member in a human or
animal body, these ends can be denoted the proximal end and a
distal end, respectively. Moreover the first electrode may be
arranged at the distal end of the elongated hollow member 102,
according to one embodiment of the present invention. According to
another embodiment of the present invention the first electrode is
arranged near the distal end of the elongated hollow member 102.
According to yet another embodiment of the present invention, the
first electrode may be arranged at another position along the
elongated hollow member 102.
[0108] According to yet another embodiment of the present invention
the first electrode is arranged along the elongated hollow member
in a way such that the first electrode 116 possesses a longitudinal
extension, along the elongated hollow member 102.
[0109] According to one embodiment of the present invention the
elongated hollow member 102 is arranged to be connected to the
radio frequency generator 110, such that the first electrode 116 of
the elongated hollow member 102 is connectable to the radio
frequency generator 110.
[0110] According to yet another embodiment of the present invention
the elongated hollow member 102 comprises an insulating sheath that
is hollow and surrounds the elongated hollow member 102. The
insulating sheath is electrically insulating and may therefore be
used to insulate at least part of the first electrode from the
surrounding tissue. The insulating sheath surrounding the elongated
hollow member 102 is slideably movable in the longitudinal
direction of the elongated hollow member 102. By sliding the
insulating sheath along the elongated hollow member 102 over the
first electrode, variation of the length of the first electrode is
enabled. The effective length of the first electrode can thus be
varied without moving the elongated hollow member in the
longitudinal direction. Also the penetration depth of the first
electrode in the tissue can be varied without altering the length
of the first electrode that is subjected to the tissue, due to
presence of the insulating sheath.
[0111] Moreover, by letting the slideable insulating sheath at
least surround the first electrode at the air-skin interface upon
operating, an unfavourable skin burn effect can effectively be
avoided. The design of the slidable sheath may thus be such that a
first part is arranged to be insertable in the tissue surrounding
the first electrode and a second part is arranged to hinder further
penetration of the second part in the tissue. This second part for
instance in the form of a flange or a collar is arranged to contact
the tissue surface, that is the skin, whereas the first part of the
sheath is arranged to penetrate the skin of the tissue, to avoid
such a skin burn effect.
[0112] According to one alternative of the present invention the
first electrode may be segmented in the longitudinal direction of
the elongated hollow member 102, that is along the elongated hollow
member. Upon insertion of such a elongated hollow member having a
segmented first electrode, in a tissue, a few of the electrode
segments may be surrounded by body tissue, whereas others may still
face the surrounding air by being outside of the body tissue,
dependent on the insertion length of the elongated hollow member
102.
[0113] Since some electrode segments will be within the body and
other will not, the impedance between the electrode segments of the
first electrode of the elongated hollow member and the counter
electrode will vary in relation to the insertion depth of the
elongated hollow member in the tissue. Whereas the impedance
between the segments facing air and the counter electrode is
essentially infinite, the impedance between a segment being
penetrated in the tissue and the counter electrode will depend on
the surrounding tissue and will typically be less than the one for
the segment facing air.
[0114] According to this embodiment the sensing unit 104 senses the
number of electrode segments that are inserted in the body, and
determines the insertion depth by way of this segment number,
wherein each segment may have a longitudinal width of approximately
1-20 mm.
[0115] According to this embodiment of the present invention the
segmentation also permits the control unit 108 to turn on/off
various segments of the electrode depending for instance on the
impedance as an indicator of the penetration depth of first
electrode of the elongated hollow member. By turning off the
segment at the air-skin interface of the elongated hollow member,
skin burn effects can successfully be avoided, while simultaneously
ensuring complete tract killing. The application of radio frequency
energy may thus be optimized according to different positions or
motions of the elongated hollow member with respect to the tissue
surrounding the electrode.
[0116] According to an alternative embodiment of the present
invention the elongated hollow member 102 comprises a coating of a
dielectric material at the proximal or distal end, being an
electrical insulator at low radio frequency frequencies for which
frequencies the coated part of the first electrode cannot conduct
electric current. Upon the usage of higher frequencies the
impedance over the dielectric coating decreases, which enables the
usage of the entire needle including the coated part.
[0117] In the following a few applications of the present invention
are described. It should be mentioned that the principle
characteristics and features of the present invention as described
above in the detailed description of the embodiments are applicable
in each one of the applications that will be described below.
[0118] Although the usage of a few features will be repeated in
connection with the specific applications below, this is not
intended to preclude the usage of other features are described
above, as indicate in the above standing paragraph.
[0119] According to one preferred embodiment of the present
invention, the arrangement 100 is arranged to be used in connection
with fine needle aspiration (FNA). Within this application the
anti-seeding technique is incorporated in an aspiration needle,
being one example of an elongated hollow member 102, enabling the
aspiration of aspirate of suspected tumour cells without the risk
of seeding malignant cells and infectious matter upon both
withdrawal and insertion of the aspiration needle in the needle
track.
[0120] In the following, a FNA arrangement comprising anti-seeding
features will be described in some detail.
[0121] According to one embodiment of the present invention the
arrangement 100 comprises a tubular needle 102, being another
example of an elongated hollow member.
[0122] The FNA needle to be inserted into the sampling site of the
human or animal body, typically comprises a tubular member with a
sharp distal end. According to one embodiment, the needle has an
external diameter in the range of up to 3 mm and a length of 15-150
mm, depending on the tumour or sampling site.
[0123] The needle may furthermore comprise a first electrode
positioned along the needle from the distal end of the needle until
a region near the proximal end of the needle, which proximal end of
the needle is electrically isolated from the radio frequency
source.
[0124] If the needle is made of metal the exterior needle surface
is preferably provided with an insulating or a dielectric material
surrounding the needle near the proximal end of the needle, such
that skin damage of the skin in direct contact with the needle, due
to the heat of the needle upon application, can be effectively
avoided. If dielectric material is used, impedance measurements to
determine penetration depth variations can still be used.
[0125] As discussed above provision of alternatives such as a
slidable insulating sheath or a segmented electrode can also be
applied to avoid skin damage, with the advantage that the
penetration depth can be varied with complete denaturation of the
entire needle tract.
[0126] As earlier determined by the inventor facilitated
punctuation of un-healthy tissue and an increased amount of
aspirate may be achieved when applying a longitudinal motion and
rotational motion to the aspiration needle. This motion inserts and
retracts the needle periodically when being applied to the
needle.
[0127] In order to avoid spreading of malignant tumour cells and
infectious matter when for instance inserting/retracting the
aspiration needle into a tissue that is healthy, a solution
comprising the application of radio frequency energy is thus
proposed.
[0128] According to another preferred embodiment of the present
invention the arrangement 100 is an anti-seeding arrangement that
is adapted for infusion of diagnostic or therapeutic substances.
The infusion needle may in all other aspects be the same as the
fine needle aspiration needle, as described above.
[0129] According to another preferred embodiment of the present
invention the arrangement is an anti-seeding arrangement that is
adapted for core biopsy. Within this application the anti-seeding
technique is incorporated in a biopsy needle, being one example of
the elongated hollow member, enabling the removal of a core biopsy
of suspected tumour cells without the risk of seeding malignant
cells or infectious matter in the needle track.
[0130] The core biopsy needle may comprise a tubular member and a
solid member provided inside said tubular member having an outer
diameter of up to 3.5 mm and length of 50-150 mm depending on the
tumour site, according to one embodiment of the present invention.
An outer diameter up to 4.5 mm and a length of 30-200 mm may
however also be provided, according to an alternative embodiment.
The solid member may be provided with a storage compartment at the
distal end for the core biopsy sample. During sampling the tubular
member is slid over the solid member, usually under spring load or
the like, to cut off tissue material in the storage
compartment.
[0131] According to one core biopsy embodiment, the solid member
may be electrically connected to the tubular member, enabling
anti-seeding properties of also the solid member.
[0132] Further, the gathering of tissue is often completed within a
fraction of a second, for the reason of the tubular and solid
member being spring loaded in relation to each other. Both of these
aspects, periodic longitudinal motion and rapid tissue gathering,
require a rapid anti-seeding procedure. In order to achieve an
appropriate anti-seeding a triggered procedure comprising pulsed
energy delivery is required, for which reason it is provided by the
present invention.
[0133] In addition to the advantage of denaturing possible cancer
cells and infectious matter in the needle track, application of
radio frequency energy brings the advantage of stopping potential
bleeding from the biopsy needle track, which becomes an even more
important feature when using relatively coarse needles.
[0134] As explained above, embodiments comprising a slidable
insulating sheath may be successfully applied in connection with
core biopsy to avoid skin burn effects and to enable the optimizing
the effective length of the first electrode.
[0135] According to yet another embodiment of the present invention
a segmented electrode may also be used in connection to this
application being core biopsy of the present invention, according
to lines as stated above.
[0136] According to yet another embodiment of the present invention
a dielectric coating may also be used in connection to this
application being core biopsy of the present invention, according
to lines as stated above.
[0137] According to another preferred embodiment of the present
invention, the anti-seeding arrangement is arranged for treatment
with radio frequency ablation of for instance malignant tissue.
Within this embodiment of the present invention the elongated
hollow member comprises a treatment ablation needle.
[0138] In one example of such a treatment ablation needle it
comprises two parallel internal channels that are connected to each
other near or at the distal end of the needle, for enabling a
cooling media to flow through the channel to enable temperature
regulation of the ablation needle.
[0139] The ablation needle further comprises a first electrode that
according to a preferred embodiment is longitudinally sectioned in
two parts. This enables optimization of the distal section for
tumour ablation treatment whereas both parts may be activated
during anti-seeding.
[0140] According to an alternative embodiment of the present
invention the ablation needle is coated at the proximal or distal
end with a dielectric material, being an electrical insulator at
low radio frequency frequencies for which frequencies the coated
part of the first electrode cannot conduct electric current to for
example avoid tissue damage. Upon the usage of higher frequencies
the impedance over the dielectric coating decreases, which enables
the usage of the entire needle including the coated part for
denaturising or impedance measuring purposes of the needle
tract.
[0141] According to an alternative embodiment of the present
invention, the ablation needle comprises a movable isolation sheath
which may be slid in the longitudinal direction of the tubular
needle 102 which results in a variation of the electrode length of
the tubular needle 102. These embodiments thus enable optimization
of the electrode length for both the ablation treatment and the
anti-seeding procedure.
[0142] According to yet another embodiment the ablation needle
comprises an electrode being sectioned in more than two
electrodes.
[0143] Within the embodiments of the present invention as described
above, the slidable sheath being used for skin burn protection, can
be placed onto the skin surface by making use of, for example, a
larger diameter of the proximal end in the form of a flange or a
collar of the tubular member, enabling penetration depth
measurements by measuring impedance.
[0144] According to an alternative embodiment of the present
invention, the arrangement adapted for radio frequency ablation
comprises numerous treatment electrodes which can be extended from
the tubular member in an umbrella like configuration during the
ablation treatment phase. Such an arrangement can be considered to
comprise one treatment section of the extendable umbrella
electrodes, whereas anti-seeding is applied to the entire tubular
member, except for the proximal end of the member, optionally being
electrically isolated from the radio frequency source.
[0145] According to another preferred embodiment of the present
invention the arrangement is an anti-seeding arrangement that is
adapted for minimally invasive surgery, inspection and sampling
such as for example for endoscopic procedures.
[0146] During minimally invasive surgery or laparoscopy several
tubular members in the form of trocars may be inserted from
incisions and/or body openings of the patient. The trocars are
typically used for inserting a camera, surgical instruments,
illumination etc. into the site. Especially during excision of
tumours the risk of tumour spread in the trocar ports is
substantial.
[0147] The first electrode may for this reason be positioned along
the tubular member as was described in connection to the fine
needle aspiration embodiment. The surgical instruments that may be
inserted in the trocar can optionally be electrically connected to
the tubular member to enable anti-seeding if appropriate. The
relative penetration depth between the trocar and the inserted
instrument may be determined by measuring the impedance, or by
mechanically, electromagnetically or acoustically determining the
penetration distance.
[0148] During robot endoscopy the anti-seeding technique can be
implemented for the tubular members of the stereo tactical excision
system of the robot. By penetration depth measurements triggering
of anti-seeding pulsing may be accomplished.
[0149] Application of slidable insulating sheaths may be used for
this application also, bringing the same or similar advantageous as
described above in connection to the other applications of the
present invention.
[0150] The usage of segmented and coated electrodes may likewise be
used for minimally invasive surgery, offering advantageous effects
similar to the ones as described above.
[0151] The described present invention thus carries the following
advantages:
[0152] Upon applying pulsed radio frequency bursts for anti-seeding
of the tracks formed, the denaturation of cells occurs within a
layer having the thickness of the order of a few cell layers
surrounding the elongated tubular member. This is an advantage
since it is desired not to affect cells outside of the track
formed.
[0153] Another advantage is that the radio frequency bursts stop
potential bleeding by denaturating the cells in the layer
surrounding the elongated tubular member.
[0154] Yet another advantage is that the thickness of the layer to
be denatured may be altered by using different power and pulse
settings. It is further advantageous that the cell denaturation may
be performed automatically, that is without manual intervention,
and instantaneously, which results in minor tissue disturbances as
compared to the usage of the equipment as disclosed in the prior
art.
[0155] It is also advantageous that the radio frequency pulsing
technique is able to denaturise the needle tract instantaneously
during very fast instrument movements for example when using a
spring loaded biopsy excision instrument or when using longitudinal
vibration to decrease penetration resistance.
[0156] Still yet another advantage is that the automatic triggering
enables denaturing of multiple tracts that may be created during
insertion.
[0157] Still yet another advantage is that this invention enables
denaturation of the whole track length.
[0158] Still yet another advantage is that this invention enables
denaturation of infectious matter during insertion for example in
transrectal procedures.
[0159] Another clear advantage is that the use of pulsed radio
frequency energy results in the absence of substantial alteration
of the sample in the tubular member, within the diagnostic
embodiments of the present invention.
[0160] Application of sensing means for the detection of movement
of the elongated hollow member together with the usage of radio
frequency power creating an essentially instantaneous denaturation
of tissue surrounding an anti-seeding electrode, provides a rapid
arrangement for anti-seeding without being directed towards time
consuming alternatives as presented by the prior art.
[0161] It is emphasized that this invention can be varied in many
ways, of which the alternative embodiments above only are examples
of a few. These different embodiments are hence non-limiting
examples. The scope of the present invention, however, is only
limited by the subsequently following claims.
* * * * *