U.S. patent application number 15/296604 was filed with the patent office on 2017-05-11 for implantable electrical stimulation leads.
The applicant listed for this patent is EndoStim, Inc.. Invention is credited to Ofer Glasberg, Paul V. Goode, Virender K. Sharma.
Application Number | 20170128716 15/296604 |
Document ID | / |
Family ID | 51388811 |
Filed Date | 2017-05-11 |
United States Patent
Application |
20170128716 |
Kind Code |
A1 |
Goode; Paul V. ; et
al. |
May 11, 2017 |
Implantable Electrical Stimulation Leads
Abstract
An implantable electrical stimulation lead for the treatment of
biological conditions includes a lead body with an electrical
connector at one end and a pair of monopolar branches at the other
end. The lead body has a length ranging from 390 mm to 490 mm to
allow for implantation from an incision site further removed from
the final positioning site of the electrodes. The branches have
lengths ranging from 50 mm to 120 mm for the both branches. These
lengths facilitate successful laparoscopic implantation at sites
with confined anatomy, such as, near the gastroesophageal junction.
The branches include needles and sutures at their ends for suturing
anchors positioned on the branches to surrounding tissue. The
needles have curves designed to facilitate maneuvering in confined
anatomy. A separate lead includes a suture loop connecting the ends
of the first and second branches rather than needles. The loop is
used to pull the lead through the working channel of an endoscope.
The anchors on the lead are porous and allow for the ingrowth of
surrounding tissue for fixing the branches in place.
Inventors: |
Goode; Paul V.; (Round Rock,
TX) ; Glasberg; Ofer; (Zichron Ya'akov, IL) ;
Sharma; Virender K.; (Paradise Valley, AZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
EndoStim, Inc. |
St. Louis |
MO |
US |
|
|
Family ID: |
51388811 |
Appl. No.: |
15/296604 |
Filed: |
October 18, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14191085 |
Feb 26, 2014 |
9498619 |
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15296604 |
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61769732 |
Feb 26, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 1/00087 20130101;
A61N 1/36007 20130101; A61B 2017/0034 20130101; A61F 5/0026
20130101; A61N 1/0509 20130101; A61B 2018/00595 20130101; A61B
18/082 20130101; A61B 1/00082 20130101 |
International
Class: |
A61N 1/05 20060101
A61N001/05; A61B 18/08 20060101 A61B018/08; A61N 1/36 20060101
A61N001/36; A61B 1/00 20060101 A61B001/00; A61F 5/00 20060101
A61F005/00 |
Claims
1. An implantable electrical lead for use in the stimulation of
biological tissues, said lead comprising: an elongate lead body
having a proximal end and a distal end, said lead body comprising
an electrically conductive inner coil, an electrically conductive
outer coil, a first insulating sheath covering said inner coil, and
a second insulating sheath covering said outer coil wherein said
lead body has a length within a range of 390 mm to 490 mm; a
connector attached to and in electrical communication with said
proximal end of said lead body; a first elongate branch having a
proximal end and a distal end, said first elongate branch
comprising said inner coil and said first insulating sheath
covering said inner coil and not comprising said outer coil and
said second insulating sheath, wherein said first branch has a
length within a range of 50 mm to 120 mm; a second elongate branch
having a proximal end and a distal end, said second elongate branch
comprising said outer coil and said second insulating sheath
covering said outer coil and not comprising said inner coil and
said first insulating sheath, wherein said proximal end of said
first branch and said proximal end of said second branch join to
form said distal end of said lead body, wherein said second branch
has a length within a range of 50 mm to 120 mm; a first anchoring
element and a first electrode attached to said first branch and
positioned proximate said distal end of said first branch; and, a
second anchoring element and a second electrode attached to said
second branch and positioned proximate said distal end of said
second branch.
2. The implantable electrical lead of claim 1, further comprising a
first length of suturing material and a second length of suturing
material, each having a proximal end and a distal end, wherein said
proximal end of said first length of said suturing material is
attached to said distal end of said first branch and said proximal
end of said second length of said suturing material is attached to
said distal end of said second branch.
3. The implantable electrical lead of claim 2, wherein said first
and second lengths of suturing material are each in a range of 55
to 65 mm.
4. The implantable electrical lead of claim 2, further comprising a
first needle attached to said distal end of said first length of
suturing material and a second needle attached to said distal end
of said second length of suturing material, wherein said first
needle and said first length of suturing material are used to
suture said first anchoring element to a biological tissue and said
second needle and said second length of suturing material are used
to suture said second anchoring element to a biological tissue.
5. The implantable electrical lead of claim 4, wherein said first
and second needles are each within a range of 1/4 to 3/8 of a
circle curve needles with a length ranging from 18 to 23 mm and
include a base having a diameter in a range of 0.68 mm to 0.78
mm.
6. The implantable electrical lead of claim 1, wherein a distal end
of said outer coil is positioned at said distal end of said lead
body, said lead further comprising an additional electrically
conductive coil having a proximal end and a distal end and
comprising said second branch, wherein said proximal end of said
additional coil is attached to said distal end of said outer coil
and said second anchoring element and said second electrode are
attached to and positioned proximate said distal end of said
additional coil and said second insulating sheath extends over said
additional coil.
7. The implantable electrical lead of claim 1, further comprising a
sleeve covering the distal end of said lead body and the proximal
ends of said first branch and said second branch.
8. The implantable electrical lead of claim 1, further comprising a
marking element on said first branch to serve as a visual
indicator.
9. The implantable electrical lead of claim 1, wherein said first
insulating sheath extends over a proximal portion of said first
electrode and said second insulating sheath extends over a proximal
portion of said second electrode such that, after said lead is
implanted, said insulating sheaths are pulled partially in a
proximal direction to expose said proximal portions of said
electrodes.
10. The implantable electrical lead of claim 9, wherein said first
and second insulating sheaths extend in a range of 1 to 5 mm over
said first and second electrodes.
11. The implantable electrical lead of claim 9, wherein, after said
lead is implanted, a total exposed length of said electrodes is in
a range of 1 to 10 mm.
12. A lead delivery catheter to be used with an endoscope or a
laparoscope and for implanting the electrical stimulation lead of
claim 1 in the body of a patient, said catheter comprising: a
catheter body having a proximal end, a distal end, and a lumen
within; an inflatable balloon attached to said distal end of said
catheter body; and, a grasping mechanism attached to said distal
end of said catheter body for grasping said lead.
13. The catheter of claim 12, further comprising a light source
providing illumination at its distal end.
14. The catheter of claim 12, further comprising a camera at its
distal end.
15. The catheter of claim 12, further comprising a bipolar
electrocautery electrode at its distal end.
16. The catheter of claim 15, wherein said bipolar electrocautery
electrode is incorporated into said grasping mechanism.
17. An implantable electrical lead for use in the stimulation of
biological tissues, said lead comprising: a Y shaped structure
comprising a central portion, having a proximal end and a distal
end, a first prong, and a second prong, each prong having a
proximal end and a distal end, wherein said proximal ends of said
first and second prongs join together to form said distal end of
said central portion, further wherein: said central portion
comprises an electrically conductive inner coil covered by a first
insulating sheath and an electrically conductive outer coil covered
by a second insulating sheath, wherein said outer coil covered by
said second insulating sheath is positioned coaxially over said
inner coil covered by said first insulating sheath and said central
portion has a length within a range of 390 mm to 490 mm, further
wherein a connector is attached to and in electrical communication
with said proximal end of said central portion; said first prong
comprises said inner coil covered by said first insulating sheath
and does not comprise said outer coil covered by said second
insulating sheath, wherein said first prong has a length within a
range of 50 mm to 120 mm, further wherein a first anchoring element
and a first electrode are attached to said first prong and are
positioned proximate said distal end of said first prong, said
first anchoring element configured to permit the ingrowth of
biological tissues; said second prong comprises said outer coil
covered by said second insulating sheath and does not comprises
said inner coil covered by said first insulating sheath, wherein
said second prong has a length within a range of 50 mm to 120 mm,
further wherein a second anchoring element and a second electrode
are attached to said second prong and positioned proximate said
distal end of said second prong, said second anchoring element
configured to permit the ingrowth of biological tissues; and, a
length of suturing material having a first end and a second end,
wherein said first end of said length of suturing material is
attached to said distal end of said first prong and said second end
of said length of suturing material is attached to said distal end
of said second prong, joining said first and second prongs, said
length of suturing material forming a loop.
18. The implantable electrical lead of claim 17, wherein said
length of suturing material is in a range of 10 to 150 mm.
19. The implantable electrical lead of claim 17, wherein a distal
end of said outer coil is positioned at said distal end of said
central portion, said lead further comprising an additional
electrically conductive coil having a proximal end and a distal end
and comprising said second prong, wherein said proximal end of said
additional coil is attached to said distal end of said outer coil
and said distal end of said additional coil is attached to said
second end of said length of suturing material, further wherein
said second anchoring element and said second electrode are
attached to and positioned proximate said distal end of said
additional coil and said second insulating sheath extends over said
additional coil.
20. A method of implanting an electrical stimulation lead having a
connector, a first branch with a first electrode and first
anchoring element and a second branch with a second electrode and
second anchoring element, into a patient, said method comprising
the steps of: inserting a distal end of an endoscope into a natural
orifice of said patient; inserting a lead delivery catheter into a
working channel of said endoscope, said lead delivery catheter
comprising: a catheter body having a proximal end, a distal end,
and a lumen within; an inflatable balloon attached to said distal
end of said catheter body; and, a grasping mechanism attached to
said distal end of said catheter body for grasping said lead;
creating an incision in the internal wall of a body cavity entered
via said orifice; advancing said distal end of said catheter
through said incision into a target anatomy area, wherein said
target anatomy area comprises the outer walls of the esophagus and
stomach and surrounding tissues proximate the gastroesophageal
junction (GEJ); inserting a laparoscope having a proximal end, a
distal end, and a lumen within into an abdomen of said patient such
that said distal end is positioned proximate said target anatomy
area; placing said lead within said lumen of said laparoscope
through said proximal end of said laparoscope; pulling on said loop
of said lead via said grasping mechanism on said catheter to draw
said lead into said target anatomy area; positioning the first
branch and the second branch of said lead such that said first and
second electrodes are positioned proximate the target anatomy;
positioning said first anchoring element and said second anchoring
element proximate surrounding tissues to permit growth of said
surrounding tissues into said anchoring elements to secure said
branches; and, attaching said connector of said lead to an
electrical pulse generator.
Description
CROSS-REFERENCE
[0001] The present application is a continuation application of
U.S. patent application Ser. No. 14/191,085, entitled "Implantable
Electrical Stimulation Leads" and filed on Feb. 26, 2014, which
relies on U.S. Provisional Patent Application No. 61/769,732, of
the same title and filed on Feb. 26, 2013, for priority. The
aforementioned applications are herein incorporated by
reference.
[0002] U.S. patent application Ser. No. 13/602,184, entitled
"Endoscopic Lead Implantation Method", filed on Sep. 2, 2012, and
assigned to the applicant of the present invention, is herein
incorporated by reference in its entirety.
FIELD
[0003] The present specification relates generally to implantable
leads used in the electrical stimulation of human tissues. More
particularly, the present specification relates to implantable
electrical stimulation leads useful in the stimulation of
anatomical structures proximate the gastroesophageal junction.
BACKGROUND
[0004] Electrical stimulation of nerves and surrounding tissue is
used to treat a variety of conditions. For example, electrical
stimulation can be used to restore partial function to limbs or
organs following traumatic injury. Electrical stimulation can also
be used to reduce pain. Specifically, electrical stimulation can be
used to treat disorders associated with the gastrointestinal (GI)
system, such as, obesity and gastroesophageal reflux disease
(GERD).
[0005] Obesity is a common condition and a major public health
problem in developed nations including the United States of
America. As of 2009, more than two thirds of American adults,
approximately 127 million people, were either overweight or obese.
Data suggest that 300,000 Americans die prematurely from
obesity-related complications each year. Many children in the
United States are also either overweight or obese. Hence, the
overall number of overweight Americans is expected to rise in the
future. It has been estimated that obesity costs the United States
approximately $100 billion annually in direct and indirect health
care expenses and in lost productivity. This trend is also apparent
in many other developed countries.
[0006] For adults, the body mass index (BMI) is used to determine
if one is overweight or obese. A person's BMI is calculated by
multiplying body weight in pounds by 703 and then dividing the
total by height in inches squared. A person's BMI is expressed as
kilograms per meter squared.
[0007] An adult is considered overweight if his or her BMI is
between 25 and 30 kg/m2. Obesity is defined as possessing a BMI
between 30 and 40 kg/m2. A BMI greater than 30 kg/m.sup.2 is
associated with significant co-morbidities. Morbid obesity is
defined as possessing either a body weight more than 100 pounds
greater than ideal or a body mass index (BMI) greater than 40
kg/m.sup.2. Approximately 5% of the U.S. population meets at least
one of the criteria for morbid obesity. Morbid obesity is
associated with many diseases and disorders including, for example:
diabetes; hypertension; heart attacks; strokes; dyslipidemia; sleep
apnea; pickwickian syndrome; asthma; lower back and disc disease;
weight-bearing osteoarthritis of the hips, knees, ankles and feet;
thrombophlebitis and pulmonary emboli; intertriginous dermatitis;
urinary stress incontinence; gastroesophageal reflux disease
(GERD); gallstones; and, sclerosis and carcinoma of the liver. In
women, infertility, cancer of the uterus, and cancer of the breast
are also associated with morbid obesity. Taken together, the
diseases associated with morbid obesity markedly reduce the odds of
attaining an average lifespan. The sequelae raise annual mortality
in affected people by a factor of 10 or more.
[0008] Gastro-esophageal reflux disease (GERD) is another common
health problem and is expensive to manage in both primary and
secondary care settings. This condition results from exposure of
esophageal mucosa to gastric acid as the acid refluxes from the
stomach into the esophagus. The acid damages the esophageal mucosa
resulting in heartburn, ulcers, bleeding, and scarring, and long
term complications such as Barrett's esophagus (pre-cancerous
esophageal lining) and adeno-cancer of the esophagus.
[0009] Gastric electrical stimulation (GES) is aimed at treating
both obesity and GERD. GES employs an implantable, pacemaker-like
device to deliver low-level electrical stimulation to the
gastrointestinal tract. For obesity, GES operates by disrupting the
motility cycle and/or stimulating the enteric nervous system,
thereby increasing the duration of satiety experienced by the
patient. The procedure involves the surgeon suturing electrical
leads to the outer lining of the stomach wall. The leads are then
connected to the device, which is implanted just under the skin in
the abdomen. Using an external programmer that communicates with
the device, the surgeon establishes the level of electrical
stimulation appropriate for the patient. The Abiliti.RTM.
implantable gastric stimulation device, manufactured by IntraPace,
is currently available in Europe for treatment of obesity.
[0010] In another example, Medtronic offers for sale and use the
Enterra.TM. Therapy, which is indicated for the treatment of
chronic nausea and vomiting associated with gastroparesis when
conventional drug therapies are not effective. The Enterra.TM.
Therapy uses mild electrical pulses to stimulate the stomach.
According to Medtronic, this electrical stimulation helps control
the symptoms associated with gastroparesis, including nausea and
vomiting.
[0011] Electrical stimulation has also been suggested for use in
the treatment of GERD, wherein the stimulation is supplied to the
lower esophageal sphincter (LES). For example, in U.S. Pat. No.
6,901,295, assigned to Endostim, Inc., "A method and apparatus for
electrical stimulation of the lower esophageal sphincter (LES) is
provided. Electrode sets are placed in the esophagus in an
arrangement that induce contractions of the LES by electrical
stimulation of the surrounding tissue and nerves. The electrical
stimulus is applied by a pulse generator for periods of varying
duration and varying frequency so as to produce the desired
contractions. The treatment may be short-term or may continue
throughout the life of the patient in order to achieve the desired
therapeutic effect. The stimulating electrode sets can be used
either alone or in conjunction with electrodes that sense
esophageal peristalsis. The electrode sets can be placed
endoscopically, surgically or radiologically." The referenced
invention relies on sensing certain physiological changes in the
esophagus, such as changes in esophageal pH, to detect acid reflux.
Once a change in esophageal pH is recognized, the system generates
an electrical stimulation in an attempt to instantaneously close
the LES and abort the episode of acid reflux. U.S. Pat. No.
6,901,295 is hereby incorporated by reference in its entirety. The
leads used in electrical stimulation of gastrointestinal tissues
traditionally comprise elongated or coiled, insulated wires or
cables having a means for attachment to an electrical pulse
generator at one end and one or more exposed electrodes at the
other end. The leads are typically anchored in place such that the
electrodes are positioned and remain proximate the target nerve or
tissues. Anchoring is often accomplished by suturing the electrode
containing ends of the leads proximal to the electrodes and into
the surrounding tissue. Traditional leads often comprise a needle
attached to a length of suture nylon at the distal end of each
branch of the lead. A butterfly shaped anchoring element is
positioned on each branch just proximal to each electrode. The
needle and suture nylon are used to create a pathway for the
electrode to be inserted into the tissue, with the needle and most
of the suture being removed thereafter. The remaining suture is
used as a tether onto which at least one clip (e.g., titanium clip)
is used to provide a distal stop thus preventing the electrode from
backing out until sufficient fibrosis is formed.
[0012] While current electrical leads are effective in transmitting
electrical stimulation to target nerves and tissues, they are not
without their drawbacks. For example, the overall length of current
leads limits the implantation site of the stimulator to which they
connect. A lead that is intended to have its electrodes positioned
proximate the gastroesophageal junction is often implanted through
the abdominal wall via laparoscopy, but requiring the stimulator
and its unsightly scar at the patient's exposed abdomen. Therefore,
what is needed is a lead having an increased overall length to
permit stimulator implantation at points further from the therapy
site, whereby the scar could be covered by most clothing apparel
(e.g., male and female swimsuits) or the implant access could be
through the umbilicus.
[0013] In addition, with regard to bipolar leads, the monopolar
branches that extend beyond the bifurcation point are often too
long. Lengthy monopolar branches can become entangled in
surrounding tissues, leading to dislodgment of anchored leads and
stricture formation. Therefore, what is needed is a bipolar lead
having shortened monopolar branches. Further, traditional leads are
often pulled backward to facilitate anchoring, causing the proximal
2 to 3 mm of conductive material to become exposed. Exposed
conductive material can result in inadvertent electrical
stimulation of non-target tissues as well as less stimulation
current reaching the target tissues. Therefore, what is also needed
is a lead having additional insulation closer to the
electrodes.
[0014] Traditional leads also include electrodes that are too large
for certain applications, including stimulation of the
gastroesophageal junction. Oversized electrodes can also result in
inadvertent electrical stimulation of non-target tissues.
Therefore, what is needed is a lead having smaller sized
electrodes. In addition, the space in which to work surrounding the
gastroesophageal junction (GEJ) is relatively confined compared to
other spaces, such as, around the body of the stomach. Traditional
leads having long suture nylons tempt the surgeon to use the same
needle and suture for anchoring the lead proximal to the electrode;
however, this suture material is chosen for applying distal clips
and not anchoring the leads. Therefore, what is also needed is a
lead having shorter suture nylons on each branch such that this
needle and suture is not long enough to be used for anchoring the
leads proximal to the electrode. Having shorter suture nylons also
reduces the number of pulling maneuvers required in order to bring
the electrode(s) into final position. Traditional leads often
include a curved needle for anchoring.
[0015] The degree of curvature of the needle is often not
sufficient when considering the adjacent tissues, resulting in
injury to the tissue. What is needed is a needle curvature which
will allow the user to significantly bury the electrode within the
target tissue while also making the needle easily retrievable from
the tissue exit site without puncturing or scraping nearby
tissues.
[0016] Therefore, what is needed specifically for GEJ implantation
is a lead having a needle with a degree of curvature specific to
the target and surrounding tissue. Some traditional leads include
an additional suture sleeve over the lead body to prevent damage to
surrounding tissues during implantation. However, this sleeve tends
to attract much fibrosis. Therefore, what is also needed is a lead
having no additional anchoring sleeve.
[0017] Traditional leads are often implanted laparoscopically via
an incision site on the abdomen. The incision typically leaves
several visible scars and use of anchoring needles usually results
in some trauma to the internal tissues. Applying suture anchors
through an endoscope are difficult, specifically in the confined
space of the GEJ or in a small endoscopic tunnel. Therefore, there
is also a need for an electrical lead that can be implanted using
an endoscope and can be anchored to surrounding tissues without
using needles and sutures.
SUMMARY
[0018] The present specification discloses an implantable
electrical lead for use in the stimulation of biological tissues,
said lead comprising: an elongate lead body having a proximal end
and a distal end, said lead body comprising an electrically
conductive inner coil, an electrically conductive outer coil, a
first insulating sheath covering said inner coil, and a second
insulating sheath covering said outer coil wherein said lead body
has a length within a range of 390 mm to 490 mm; a connector
attached to and in electrical communication with said proximal end
of said lead body; a first elongate branch having a proximal end
and a distal end, said first elongate branch comprising said inner
coil and said first insulating sheath covering said inner coil and
not comprising said outer coil and said second insulating sheath,
wherein said first branch has a length within a range of 50 mm to
120 mm; a second elongate branch having a proximal end and a distal
end, said second elongate branch comprising said outer coil and
said second insulating sheath covering said outer coil and not
comprising said inner coil and said first insulating sheath,
wherein said proximal end of said first branch and said proximal
end of said second branch join to form said distal end of said lead
body, wherein said second branch has a length within a range of 50
mm to 120 mm; a first anchoring element and a first electrode
attached to said first branch and positioned proximate said distal
end of said first branch; and, a second anchoring element and a
second electrode attached to said second branch and positioned
proximate said distal end of said second branch.
[0019] Optionally, in one embodiment, the implantable electrical
lead further comprises a first length of suturing material and a
second length of suturing material, each having a proximal end and
a distal end, wherein said proximal end of said first length of
said suturing material is attached to said distal end of said first
branch and said proximal end of said second length of said suturing
material is attached to said distal end of said second branch. In
various embodiments, the first and second lengths of suturing
material are each in a range of 55 to 65 mm. In one embodiment, the
implantable electrical lead further comprises a first needle
attached to said distal end of said first length of suturing
material and a second needle attached to said distal end of said
second length of suturing material, wherein said first needle and
said first length of suturing material are used to suture said
first anchoring element to a biological tissue and said second
needle and said second length of suturing material are used to
suture said second anchoring element to a biological tissue. In
various embodiments, the first and second needles are each within a
range of 1/4 to 3/8 of a circle curve needles with a length ranging
from 18 to 23 mm and include a base having a diameter in a range of
0.68 mm to 0.78 mm.
[0020] Optionally, in one embodiment, wherein a distal end of said
outer coil is positioned at said distal end of said lead body, said
lead further comprises an additional electrically conductive coil
having a proximal end and a distal end and comprising said second
branch, wherein said proximal end of said additional coil is
attached to said distal end of said outer coil and said second
anchoring element and said second electrode are attached to and
positioned proximate said distal end of said additional coil and
said second insulating sheath extends over said additional
coil.
[0021] Optionally, in one embodiment, the implantable electrical
lead further comprises a sleeve covering the distal end of said
lead body and the proximal ends of said first branch and said
second branch.
[0022] Optionally, in one embodiment, the implantable electrical
lead further comprises a marking element on said first branch to
serve as a visual indicator.
[0023] Optionally, in one embodiment, said first insulating sheath
extends over a proximal portion of said first electrode and said
second insulating sheath extends over a proximal portion of said
second electrode such that, after said lead is implanted, said
insulating sheaths are pulled partially in a proximal direction to
expose said proximal portions of said electrodes. In various
embodiments, the first and second insulating sheaths extend in a
range of 1 to 5 mm over said first and second electrodes. In
various embodiments, after said lead is implanted, a total exposed
length of said electrodes is in a range of 1 to 10 mm.
[0024] The present specification also discloses a lead delivery
catheter to be used with an endoscope or a laparoscope and for
implanting the electrical stimulation lead described above in the
body of a patient, said catheter comprising: a catheter body having
a proximal end, a distal end, and a lumen within; an inflatable
balloon attached to said distal end of said catheter body; and, a
grasping mechanism attached to said distal end of said catheter
body for grasping said lead.
[0025] Optionally, in one embodiment, the catheter further
comprises a light source providing illumination at its distal
end.
[0026] Optionally, in one embodiment, the catheter further
comprises a camera at its distal end.
[0027] Optionally, in one embodiment, the catheter further
comprises a bipolar electrocautery electrode at its distal end. In
one embodiment, the bipolar electrocautery electrode is
incorporated into said grasping mechanism.
[0028] The present specification also discloses an implantable
electrical lead for use in the stimulation of biological tissues,
said lead comprising: a Y shaped structure comprising a central
portion, having a proximal end and a distal end, a first prong, and
a second prong, each prong having a proximal end and a distal end,
wherein said proximal ends of said first and second prongs join
together to form said distal end of said central portion, further
wherein: said central portion comprises an electrically conductive
inner coil covered by a first insulating sheath and an electrically
conductive outer coil covered by a second insulating sheath,
wherein said outer coil covered by said second insulating sheath is
positioned coaxially over said inner coil covered by said first
insulating sheath and said central portion has a length within a
range of 390 mm to 490 mm, further wherein a connector is attached
to and in electrical communication with said proximal end of said
central portion; said first prong comprises said inner coil covered
by said first insulating sheath and does not comprise said outer
coil covered by said second insulating sheath, wherein said first
prong has a length within a range of 50 mm to 120 mm, further
wherein a first anchoring element and a first electrode are
attached to said first prong and are positioned proximate said
distal end of said first prong, said first anchoring element
configured to permit the ingrowth of biological tissues; said
second prong comprises said outer coil covered by said second
insulating sheath and does not comprises said inner coil covered by
said first insulating sheath, wherein said second prong has a
length within a range of 50 mm to 120 mm, further wherein a second
anchoring element and a second electrode are attached to said
second prong and positioned proximate said distal end of said
second prong, said second anchoring element configured to permit
the ingrowth of biological tissues; and, a length of suturing
material having a first end and a second end, wherein said first
end of said length of suturing material is attached to said distal
end of said first prong and said second end of said length of
suturing material is attached to said distal end of said second
prong, joining said first and second prongs, said length of
suturing material forming a loop.
[0029] In various embodiments, the length of suturing material is
in a range of 10 to 150 mm.
[0030] Optionally, in one embodiment, wherein a distal end of said
outer coil is positioned at said distal end of said central
portion, said lead further comprises an additional electrically
conductive coil having a proximal end and a distal end and
comprising said second prong, wherein said proximal end of said
additional coil is attached to said distal end of said outer coil
and said distal end of said additional coil is attached to said
second end of said length of suturing material, further wherein
said second anchoring element and said second electrode are
attached to and positioned proximate said distal end of said
additional coil and said second insulating sheath extends over said
additional coil.
[0031] The present specification also discloses a method of
implanting an electrical stimulation lead having a connector, a
first branch with a first electrode and first anchoring element and
a second branch with a second electrode and second anchoring
element, into a patient, said method comprising the steps of:
inserting a distal end of an endoscope into a natural orifice of
said patient; inserting a lead delivery catheter into a working
channel of said endoscope, said lead delivery catheter comprising:
a catheter body having a proximal end, a distal end, and a lumen
within; an inflatable balloon attached to said distal end of said
catheter body; and, a grasping mechanism attached to said distal
end of said catheter body for grasping said lead; creating an
incision in the internal wall of a body cavity entered via said
orifice; advancing said distal end of said catheter through said
incision into a target anatomy area, wherein said target anatomy
area comprises the outer walls of the esophagus and stomach and
surrounding tissues proximate the gastroesophageal junction (GEJ);
inserting a laparoscope having a proximal end, a distal end, and a
lumen within into an abdomen of said patient such that said distal
end is positioned proximate said target anatomy area; placing said
lead within said lumen of said laparoscope through said proximal
end of said laparoscope; pulling on said loop of said lead via said
grasping mechanism on said catheter to draw said lead into said
target anatomy area; positioning the first branch and the second
branch of said lead such that said first and second electrodes are
positioned proximate the target anatomy; positioning said first
anchoring element and said second anchoring element proximate
surrounding tissues to permit growth of said surrounding tissues
into said anchoring elements to secure said branches; and,
attaching said connector of said lead to an electrical pulse
generator.
[0032] The aforementioned and other embodiments of the present
invention shall be described in greater depth in the drawings and
detailed description provided below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] These and other features and advantages of the present
invention will be further appreciated, as they become better
understood by reference to the detailed description when considered
in connection with the accompanying drawings:
[0034] FIG. 1A is a side view illustration of one embodiment of an
implantable electrical stimulation lead of the present
specification;
[0035] FIG. 1B is an oblique side view illustration of the
embodiment of the implantable electrical stimulation lead of FIG.
1A;
[0036] FIG. 2 is a close-up view illustration of the first and
second monopolar branches of the embodiment of the implantable
electrical stimulation lead of FIG. 1A;
[0037] FIG. 3 is a close-up view illustration of the anchors and
insulated proximal portions of the electrodes of the monopolar
branches of the embodiment of the implantable electrical
stimulation lead of FIG. 1A;
[0038] FIG. 4 is a close-up view illustration of the lengths of
suture material attached to the distal ends of the monopolar
branches of the embodiment of the implantable electrical
stimulation lead of FIG. 1A;
[0039] FIG. 5 is a close-up view illustration of the needle used to
suture in place the anchors of the embodiment of the implantable
electrical stimulation lead of FIG. 1A;
[0040] FIG. 6 is a side view illustration of another embodiment of
an implantable electrical stimulation lead, depicting a length of
suture material joining the distal ends of the two monopolar
branches:
[0041] FIG. 7 is a side view illustration of one embodiment of a
lead delivery catheter used to implant a needleless electrical
stimulation lead using the natural orifice transluminal endoscopic
surgery (NOTES) technique; and,
[0042] FIG. 8 is a flowchart illustrating one embodiment of the
steps involved in implanting a needleless electrical stimulation
lead using an endoscope.
DETAILED DESCRIPTION
[0043] The present specification discloses an implantable
electrical stimulation lead that is dimensioned specifically for
use in confined anatomy, particularly the area proximate the
gastroesophageal junction (GEJ). The lead is designed to be
implanted laparoscopically and includes needles for suturing
anchoring elements to the neighboring anatomy. The present
specification also discloses another, needleless implantable
electrical stimulation lead that is designed to be implanted
through the working channel of an endoscope and includes anchoring
elements that eliminate the need for suturing the lead to
surrounding tissues. The present specification also discloses a
lead delivery catheter used for implanting the needleless
electrical stimulation lead through the working channel of an
endoscope. The present invention is directed toward multiple
embodiments. The following disclosure is provided in order to
enable a person having ordinary skill in the art to practice the
invention. Language used in this specification should not be
interpreted as a general disavowal of any one specific embodiment
or used to limit the claims beyond the meaning of the terms used
therein. The general principles defined herein may be applied to
other embodiments and applications without departing from the
spirit and scope of the invention. Also, the terminology and
phraseology used is for the purpose of describing exemplary
embodiments and should not be considered limiting. Thus, the
present invention is to be accorded the widest scope encompassing
numerous alternatives, modifications and equivalents consistent
with the principles and features disclosed. For purpose of clarity,
details relating to technical material that is known in the
technical fields related to the invention have not been described
in detail so as not to unnecessarily obscure the present
invention.
[0044] In one embodiment, an implantable electrical stimulation
lead is a bipolar lead and comprises an elongate lead body having a
proximal end and a distal end. The lead body is comprised of an
electrically conductive material with an overlaying insulating
sheath. Attached to the proximal end is a coupling means for
connecting the lead to a pulse generator such that the two are in
electrical communication. In one embodiment, the coupling means is
an international standard (IS-1) connector system. The distal end
of the lead body includes a bifurcation sleeve. In one embodiment,
the electrically conductive material of the lead body includes an
inner coil and an outer coil, electrically insulated from each
other, which split into separate branches within the bifurcation
sleeve.
[0045] The inner coil and outer coil continue distally beyond the
bifurcation sleeve as first and second monopolar branches. In one
embodiment, the first and second monopolar branches comprise first
and second elongate branch bodies respectively, each having a
proximal end and a distal end. In one embodiment, the first branch
body of the first monopolar branch comprises the continuation of
the inner coil of the lead body and the second branch body of the
second monopolar branch comprises a partial continuation of the
outer coil of lead body attached to an additional coil. The
additional coil is an elongate coil having a proximal end and a
distal end with its proximal end attached to the distal end of the
outer coil. In another embodiment, the first branch body of the
first monopolar branch comprises the continuation of the inner coil
of the lead body and the second branch body of the second monopolar
branch comprises the continuation of the outer coil of lead body.
The proximal ends of the first and second branch bodies join
together within the bifurcation sleeve as described above. The
distal ends of the first and second branch bodies each have a
length of suturing material attached to them. In one embodiment,
the suture is a monofilament using nylon as the material. Attached
to the distal end of each length of suturing material is a needle.
In one embodiment, the needle is a curved needle. In one
embodiment, the needle is a straight needle. Both the first and
second branch bodies additionally include at least one anchor and
at least one electrode. Each electrode is in electrical
communication with either the inner or outer coil of its respective
branch body. In one embodiment, the anchor has a butterfly shape
with two holes, one on each side, for passing the needle and suture
material during anchoring. Each electrode is positioned just distal
to each anchor. In one embodiment, the first monopolar branch has a
length that is longer than that of the second monopolar branch. In
another embodiment, the first and second monopolar branches have
the same length.
[0046] In one embodiment, a portion of each electrode is insulated
by a length of tubing. In one embodiment, the tubing extends
distally from the distal end of the anchoring element. In one
embodiment, the tubing and anchoring element are composed of
silicone.
[0047] The lead is designed to be implanted using a standard
laparoscopic technique common in the prior art.
[0048] In another embodiment, an implantable electrical stimulation
lead is intended for implantation via the working channel of an
endoscope and includes anchoring elements rather than a needle and
sutures for anchoring. In this embodiment, the implantable
electrical stimulation lead is a bipolar lead and also comprises an
elongate lead body having a proximal end and a distal end. The lead
body is comprised of an electrically conductive material with an
overlaying insulating sheath. Attached to the proximal end is a
coupling means for connecting the lead to a pulse generator such
that the two are in electrical communication. In one embodiment,
the coupling means is an IS-1 connector system. The distal end of
the lead body includes a bifurcation sleeve. In one embodiment, the
electrically conductive material of the lead body includes an inner
coil and an outer coil, electrically insulated from each other,
which split into separate branches within the bifurcation
sleeve.
[0049] The inner coil and outer coil continue distally beyond the
bifurcation sleeve as first and second monopolar branches. In one
embodiment, the first and second monopolar branches comprise first
and second elongate branch bodies respectively, each having a
proximal end and a distal end. In one embodiment, the first branch
body of the first monopolar branch comprises the continuation of
the inner coil of the lead body and the second branch body of the
second monopolar branch comprises a partial continuation of the
outer coil of lead body attached to an additional coil. The
additional coil is an elongate coil having a proximal end and a
distal end with its proximal end attached to the distal end of the
outer coil. In another embodiment, the first branch body of the
first monopolar branch comprises the continuation of the inner coil
of the lead body and the second branch body of the second monopolar
branch comprises the continuation of the outer coil of lead body.
The proximal ends of the first and second branch bodies join
together within the bifurcation sleeve as described above. The
distal ends of the first and second branch bodies are connected by
a suture loop. The suture loop is designed to be grasped with
endoscopic graspers and pulled through the working channel of the
endoscope. In one embodiment, the material of the suture loop is
silk. Both the first and second branch bodies additionally include
at least one anchoring element and at least one electrode. Each
electrode is in electrical communication with either the inner or
outer coil of its respective branch body. The anchoring elements
allow for fibrosis around them in the created endoscopic tunnel so
that the electrodes remain in position. This eliminates the need
for suturing the lead branches in place. In various embodiments,
the anchoring element is a silicone sleeve having grooves, spikes,
or holes to allow for the ingrowth of fibrous tissue and anchoring.
In another embodiment, the anchoring element is comprised of a
porous material that allows fibrous ingrowth and anchoring. In one
embodiment, the porous material is a Dacron mesh. In another
embodiment, the anchoring material is made of an electrically
conductive material, such as platinum-iridium alloy, and is
electrically connected to the electrode to increase the area of
stimulation. In another embodiment, the electrodes are the anchors,
with special shapes, such as barbs, to facilitate anchoring and
tissue in-growth. Each electrode is positioned just distal to each
anchor. In one embodiment, the first monopolar branch has a length
that is longer than that of the second monopolar branch such that
the electrodes are staggered in an in-line position. In another
embodiment, the first and second monopolar branches have the same
length.
[0050] The present specification also discloses a lead delivery
catheter for use during the implantation of the needleless
electrical stimulation lead through the working channel of an
endoscope. In one embodiment, the catheter is used with the natural
orifice transluminal endoscopic surgery (NOTES) technique to
implant one or more leads proximate the lower esophageal sphincter
(LES) using an endoscopic approach or a laparoscopic approach. In
one embodiment, the catheter includes a catheter body having a
proximal end, a distal end, and a lumen within. The catheter
includes an inflatable balloon, a grasping mechanism, and a light
source at its distal end. Optionally, in one embodiment, the
catheter includes a camera at its distal end. Optionally, in one
embodiment, the catheter includes a bipolar electrode at its distal
end for electrocautery.
[0051] The leads disclosed in the various embodiments of the
present specification can be implanted into a patient using the
methods described in U.S. patent application No. 13/602,184,
entitled "Endoscopic Lead Implantation Method", filed on Sep. 2,
2012, and assigned to the applicant of the present invention, which
is herein incorporated by reference in its entirety.
[0052] FIGS. 1A and 1B are side and oblique side view illustrations
respectively, of one embodiment of an implantable electrical
stimulation lead 100 of the present specification. The lead 100 is
a bipolar lead and includes an elongate lead body 105 having a
proximal end and a distal end. The lead body 105 is comprised of an
electrically conductive inner coil and an electrically conductive
outer coil. The inner coil and outer coil are each covered by an
insulating sheath. An IS-1 connector system 107, having proximal
and distal ends, is attached to the proximal end of the lead body
105 and a bifurcation sleeve 109, having proximal and distal ends,
is coupled to the distal end of the lead body 105. In various
embodiments, the length of the lead body 105, from the proximal end
of the IS-1 connector pin 107 to the distal end of the bifurcation
sleeve 109, is in a range of 390 mm to 490 mm. In one embodiment,
the length of the lead body 105, from the proximal end of the IS-1
connector pin 107 to the distal end of the bifurcation sleeve 109,
is 433 mm. This length is greater than that encountered in the
prior art, which often measures approximately 350 mm. The greater
length allows for greater variation in implantation site. A
physician can implant the lead from a more cosmetically pleasing
position, for example, a sub-bikini line implantation site or a
transumbilical implantation site. The resulting stimulator implant
scar would not be visible on the patient's abdomen. In addition,
the greater length allows for appropriate routing of the lead to
prevent entanglement in the small bowel or a gravid uterus in a
female with child bearing potential.
[0053] The inner and outer coils of the lead body 105 separate
within the bifurcation sleeve 109 and continue distally as
monopolar branches. Referring to FIGS. 1A and 1B, the inner coil
continues distally from the distal end of the bifurcation sleeve
109 as a first monopolar branch 111, having proximal and distal
ends, and the outer coil continues distally from the distal end of
the bifurcation sleeve 109 and attaches to an additional coil 110
having proximal and distal ends, which continues as a second
monopolar branch 112 having proximal and distal ends. In another
embodiment, the outer coil continues distally from the distal end
of the bifurcation sleeve 109 as the second monopolar branch 112
having proximal and distal ends. The first monopolar branch 111
comprises the inner coil with a covering insulating sheath and
includes an anchor 113, having a proximal end and a distal end, and
an insulated electrode 115, having a proximal end and a distal end,
at a point proximate its distal end. The electrode 115 is
positioned just distal to the anchor 113. Attached to the distal
end of the first monopolar branch 111 is a length of suture
material 117, itself having a proximal end and a distal end. In one
embodiment, the suture material is composed of nylon. Attached to
the distal end of the suture material is a suture needle 119. The
second monopolar branch 112 comprises a portion of the outer coil
and an attached additional coil 110 with a covering insulating
sheath and includes an anchor 114, having a proximal end and a
distal end, and an insulated electrode 116, having a proximal end
and a distal end, at a point proximate its distal end. The
electrode 116 is positioned just distal to the anchor 114. Attached
to the distal end of the second monopolar branch 112 is a length of
suture material 118, itself having a proximal end and a distal end.
In one embodiment, the suture material is composed of nylon.
Attached to the distal end of the suture material is a suture
needle 120.
[0054] In another embodiment, each branch includes an additional
suture with needle and the anchor, in a butterfly shape, is
positioned just distal to the bifurcation sleeve. The additional
suture and position of the anchor will help maintain the anchor
flat on the esophagus after implantation. This will prevent the
anchor from pivoting and avoid extra pressure on the esophageal
wall.
[0055] FIG. 1A also includes a close-up view illustration of the
insulated electrode 115 of the first monopolar branch 111. In one
embodiment, the electrode 115 includes a covering length of
insulating material which will be discussed further with reference
to FIG. 3 below. In another embodiment, the electrode is not
covered by any insulating material.
[0056] FIG. 2 is a close-up view illustration of the first 211 and
second 212 monopolar branches of the embodiment of the implantable
electrical stimulation lead of FIG. 1A. The monopolar branches 211,
212 are depicted emanating distally from the distal end of the
bifurcation sleeve 209. Also depicted is the distal end of the lead
body 205 coupled to the bifurcation sleeve 209. The first monopolar
branch 211 includes an anchor 213 and an insulated electrode 215 at
a point proximate its distal end and the second monopolar branch
212 includes an anchor 214 and an insulated electrode 216 at a
point proximate its distal end. In various embodiments, the length
l.sub.1 of the first monopolar branch 211, from its proximal end
where it exits the distal end of the bifurcation sleeve 209 to its
distal end where it meets the proximal end of the anchor 213, is in
a range of 50 mm to 120 mm. In one embodiment, the length l.sub.1
of the first monopolar branch 211, from its proximal end where it
exits the distal end of the bifurcation sleeve 209 to its distal
end where it meets the proximal end of the anchor 213, is 70 mm.
This is shorter than the length encountered in the prior art, which
is approximately 90 mm. In various embodiments, the length l.sub.2
of the second monopolar branch 212, from its proximal end where it
exits the distal end of the bifurcation sleeve 209 to its distal
end where it meets the proximal end of the anchor 214, is in a
range of 50 mm to 120 mm. In one embodiment, the length l.sub.2 of
the second monopolar branch 212, from its proximal end where it
exits the distal end of the bifurcation sleeve 209 to its distal
end where it meets the proximal end of the anchor 214, is 60 mm.
This is shorter than the length encountered in the prior art, which
is approximately 90 mm.
[0057] The longer length of the monopolar branches in the prior art
facilitates their implantation across the gastric greater
curvature, with one electrode on each wall. The shorter lengths of
the monopolar branches of the lead of the current embodiment
facilitate placement about the GEJ, where the anatomy in more
confined. In one embodiment, the first monopolar branch 211 further
includes a visual indicator 231 at its distal end, just proximal to
the anchor 213. The visual indicator 231 indicates to the physician
that this lead contains the inner coil of the lead body. In one
embodiment, the visual indicator 231 is a black marking on the
insulation of the first monopolar branch 211. Having monopolar
branches of different lengths allows the physician to implant the
electrodes in-line with each other.
[0058] FIG. 3 is a close-up view illustration of the anchors 313,
314 and insulated proximal portions of the electrodes 315b, 316b of
the monopolar branches 311, 312 of the embodiment of the
implantable electrical stimulation lead of FIG. 1A. In one
embodiment, the electrode of the first monopolar branch 311
comprises an exposed portion 315a and an insulated, unexposed
portion 315b that is covered by a length of insulating tubing. In
various embodiments, the length l.sub.3 of the insulating tubing
covering the insulated portion of the electrode 315b is in a range
of 1 mm to 5 mm. In one embodiment, the length l.sub.3 of the
insulating tubing covering the insulated portion of the electrode
315b is 3 mm. In one embodiment, the insulating tubing is attached
to the distal end of the anchor 313. Depicted attached to the
distal end of the exposed portion of the electrode 315a is the
proximal end of a length of suture material 319. In another
embodiment, the electrode of the first monopolar branch does not
include any insulating tubing and is exposed along its entire
length (not shown).
[0059] In one embodiment, the electrode of the second monopolar
branch 312 comprises an exposed portion 316a and an insulated,
unexposed portion 316b that is covered by a length of insulating
tubing. In various embodiments, the length of the insulating tubing
covering the insulated portion of the electrode 316b of the second
monopolar branch 312 is the same as the length of the insulating
tubing covering the insulated portion of the electrode 315b of the
lead of the first monopolar branch 311, that is, in a range of 1 mm
to 5 mm. In one embodiment, the length of the insulating tubing
covering the insulated portion of the electrode 316b of the second
monopolar branch 312 is the same as the length of the insulating
tubing covering the insulated portion of the electrode 315b of the
lead of the first monopolar branch 311, that is, 3 mm. In one
embodiment, the insulating tubing covering the insulated portion of
the electrode 316b is attached to the distal end of the anchor 314.
Depicted attached to the distal end of the exposed portion of the
electrode 316a is the proximal end of a length of suture material
318. In another embodiment, the electrode of the second monopolar
branch does not include any insulating tubing and is exposed along
its entire length (not shown).
[0060] The insulating tubing covering the insulated, unexposed
portions of the electrodes 315b, 316b serve to prevent the exposure
of the proximal 2 to 3 mm of each electrode that often occurs
during anchoring as the electrodes are pulled backward slightly
over time.
[0061] In one embodiment, the insulating tubing covering the
insulated portions of the electrodes 315b, 316b is composed of
silicone. In various embodiments, the wall thickness of the
insulating tubing is in a range of 0.160 mm to 0.170 mm. In one
embodiment, the wall thickness of the insulating tubing is 0.165 mm
(0.0065 in). In one embodiment, the anchors 313, 314 are composed
of silicone. In one embodiment, the electrodes are composed of
platinum-iridium (Pt--Ir). In various embodiments, the exposed
portion of the electrodes 315a, 316a, after anchoring, is in a
range of 1 mm to 10 mm. In one embodiment, the exposed portion of
the electrodes 315a, 316a, after anchoring, is 5 mm. This length is
shorter than the average of approximately 10 mm encountered in the
prior art. The shorter electrodes have a higher charge density
which has been shown to contribute to better results.
[0062] FIG. 4 is a close-up view illustration of the lengths of
suture material 417, 418 attached to the distal ends of the
monopolar branches 411, 412 of the embodiment of the implantable
electrical stimulation lead of FIG. 1A. Also depicted are the
anchors 413, 414, exposed electrode portions 415a, 415b, and
insulating tubing covering the insulated portions of the electrodes
415b, 416b of the first 411 and second 412 monopolar branches.
Attached to the distal end of the first monopolar branch 411 and
extending distally from the exposed portion of electrode 415a is a
first length of suture material 417. The length of suture material
417 includes a proximal end and a distal end. A suture needle 419
is attached to the distal end of the suture material 417 via a
coupling means 421. In various embodiments, the length l.sub.4 of
the suture material 417 is in a range of 55 mm to 65 mm. In one
embodiment, the length l.sub.4 of the suture material 417 is 60
mm.
[0063] Attached to the distal end of the second monopolar branch
412 and extending distally from the exposed portion of electrode
416a is a second length of suture material 418. The length of
suture material 418 includes a proximal end and a distal end. A
suture needle 420 is attached to the distal end of the suture
material 418 via a coupling means 422. In various embodiments, the
length of the suture material 418 attached to the distal end of the
second monopolar branch 412 is the same as the length of the suture
material 417 attached to the distal end of the first monopolar
branch 411, that is, in a range of 55 mm to 65 mm. In one
embodiment, the length of the suture material 418 attached to the
distal end of the second monopolar branch 412 is the same as the
length of the suture material 417 attached to the distal end of the
first monopolar branch 411, that is, 60 mm.
[0064] The average length of the suture material encountered in
leads in the prior art is approximately 112 mm. For applications at
the GEJ, such a length requires the physician to perform
additional, unnecessary pulling maneuvers in order to properly
position the anchors. The area to maneuver proximate the GEJ is
limited by the proximity of the GEJ to the diaphragm. Therefore, a
lead with shorter lengths of suture material is advantageous for
such an application.
[0065] In one embodiment, the suture material is composed of nylon.
In another embodiment, the suture material is barbed, such as
V-Loc.TM. by Covidien, to improve anchoring of the electrodes.
During anchoring, a physician sutures the branches into position by
threading the needles 419, 420 through holes 433, 444 in the
anchors 413, 414 and into the surrounding tissue. In one
embodiment, the anchors 413, 414 have a butterfly shape with two
holes 433, 444 positioned on either side of each monopolar branch
411, 412.
[0066] FIG. 5 is a close-up view illustration of the needle 500
used to suture in place the anchors of the embodiment of the
implantable electrical stimulation lead of FIG. 1A. A needle 500 is
attached to the distal end of each length of suture material
emanating from the distal end of each monopolar branch. In one
embodiment, each needle 500 is attached to the distal end of the
suture material via a coupling means. In one embodiment, each
needle 500 is a 3/8 of a circle curve needle and has a length
within a range of 18 to 23 mm. In another embodiment, each needle
500 is a 1/4 of a circle curve needle and has a length within a
range of 18 to 23 mm. The needle 500 has a tapered point and is a
non-cutting needle. In various embodiments, the needle has a
diameter d at its base in a range of 0.68 mm to 0.78 mm, being at
least as large as the diameter of the insulated or non-insulated
electrode. In one embodiment, the needle has a diameter d at its
base of 0.73 mm (0.029 in), which is 0.56 mm (0.022 in) larger than
the insulating tubing of the electrode.
[0067] During anchoring, the electrode tract should be straight.
Traditional 1/2 curve sky shaped or ski needles encountered in the
prior art start with a tight bend and hence require a circular
maneuver. With such a needle, when a straight bite is attempted,
the tissue is often heavily injured, similar to what occurs with a
biopsy. The needle of the present embodiment, having a shorter
curve, can be more easily straightened when maneuvering near the
GEJ when compared to the needles of the prior art. In addition,
suturing needles and leads encountered in the prior art often
include a suture sleeve. Such sleeves tend to attract fibrosis. The
lead of the present specification does not include a sleeve so as
to minimize fibrosis.
[0068] FIG. 6 is a side view illustration of another embodiment of
an implantable electrical stimulation lead 600, depicting a length
of suture material 650 joining the distal ends of the two monopolar
branches 611, 612. The lead 600 is a bipolar lead and includes an
elongate lead body 605 having a proximal end and a distal end. The
lead body 605 is comprised of an electrically conductive inner coil
and an electrically conductive outer coil. The outer coil is
covered by an insulating sheath. An IS-1 connector system 607,
having proximal and distal ends, is attached to the proximal end of
the lead body 605 and a bifurcation sleeve 609, having proximal and
distal ends, is coupled to the distal end of the lead body 605. In
various embodiments, the length l.sub.5 of the lead body 605, from
the proximal end of the IS-1 connector system 607 to the distal end
of the bifurcation sleeve 609, is in a range of 390 mm to 490 mm.
In one embodiment, the length l.sub.5 of the lead body 605, from
the proximal end of the IS-1 connector system 607 to the distal end
of the bifurcation sleeve 609, is 433 mm.
[0069] The inner and outer coils of the lead body 605 separate
within the bifurcation sleeve 609 and continue distally as
monopolar branches. The inner coil continues distally from the
distal end of the bifurcation sleeve 609 as a first monopolar
branch 611, having proximal and distal ends, and a portion of the
outer coil continues distally from the distal end of the
bifurcation sleeve 609 and attaches to an additional coil 610,
having proximal and distal ends, which continues as a second
monopolar branch 612 having proximal and distal ends. In another
embodiment, the outer coil continues distally from the distal end
of the bifurcation sleeve 609 as the second monopolar branch 612
having proximal and distal ends. The first monopolar branch 611
comprises the inner coil with a covering insulating sheath and
includes an anchor 613, having a proximal end and a distal end, and
an electrode 615, having a proximal end and a distal end, at a
point proximate its distal end. The electrode 615 is positioned
just distal to the anchor 613. The second monopolar branch 612
comprises a portion of the outer coil and an attached additional
coil 610 with a covering insulating sheath and includes an anchor
614, having a proximal end and a distal end, and an electrode 616,
having a proximal end and a distal end, at a point proximate its
distal end. The electrode 616 is positioned just distal to the
anchor 614. In various embodiments, the length l.sub.6 of the first
monopolar branch 611, from its proximal end where it exits the
distal end of the bifurcation sleeve 609 to its distal end where it
meets the proximal end of the anchor 613, is in a range of 50 mm to
120 mm. In one embodiment, the length l.sub.6 of the first
monopolar branch 611, from its proximal end where it exits the
distal end of the bifurcation sleeve 609 to its distal end where it
meets the proximal end of the anchor 613, is 70 mm. In various
embodiments, the length l.sub.7 of the second monopolar branch 612,
from its proximal end where it exits the distal end of the
bifurcation sleeve 609 to its distal end where it meets the
proximal end of the anchor 614, is in a range of 50 mm to 120 mm.
In one embodiment, the length l.sub.7 of the second monopolar
branch 612, from its proximal end where it exits the distal end of
the bifurcation sleeve 609 to its distal end where it meets the
proximal end of the anchor 614, is 60 mm.
[0070] In various embodiments, the length of the electrodes 615,
616 is in a range of 1 mm to 10 mm. In one embodiment, the length
of the electrodes 615, 616 is 5 mm. The different lengths of the
first and second monopolar branches allow the electrodes to be
positioned in a staggered, in-line configuration. In various
embodiments, after anchoring, the electrodes are positioned in a
range of 1 to 20 mm apart from one another. In one embodiment,
after anchoring, the electrodes are positioned 10 mm apart from one
another.
[0071] A length of suture material 650, having a first end and a
second end, joins the two monopolar branches 611, 612. The first
end of the length of suture material 650 is attached to the distal
end of the first monopolar branch 611, just distal to the electrode
615, and the second end of the length of suture material 650 is
attached to the distal end of the second monopolar branch 612, just
distal to the electrode 616. The suture material 650 acts as a loop
to direct the lead 600 during implantation. In various embodiments,
the suture material has a length of 10 to 150 mm. In one
embodiment, the suture material has a length of 60 mm. In one
embodiment, the suture material 650 is composed of nylon. In
various embodiments, the total length of the lead 600 from the
proximal end of the IS-1 connector system 607 to the proximal end
of the electrode 615 of the first monopolar branch 611 is in a
range of 500 mm to 540 mm. In one embodiment, the total length of
the lead 600 from the proximal end of the IS-1 connector system 607
to the proximal end of the electrode 615 of the first monopolar
branch 611 is 520 mm.
[0072] The implantable electrical implantation lead 600 is designed
to be implanted through the working channel of an endoscope. A
physician inserts an endoscope into a patient using natural orifice
transluminal endoscopic surgery (NOTES). In NOTES, a physician
passes an endoscope through a natural orifice in the patient's
body, such as, the mouth, urethra, or anus, creates an incision in
the wall of an internal organ, such as, the stomach, bladder, or
colon, and then passes the endoscope through the incision and into
the target area or lumen of the organ. The incision is always
internal with a NOTES technique, therefore, no visible scar
remains. For the present embodiment, once the distal end of the
endoscope is positioned proximate the target anatomy, the physician
uses endoscopic graspers to grasp the suture material 650 of the
lead 600 and then pulls the lead 600 through the working channel of
the endoscope. Alternatively, the lead could be passed through a
working channel of a laparoscopic and pulled through the endoscopic
tunnel proximate to the target tissue thus eliminating the need to
dissect to expose the target tissue. The monopolar branches 611,
612 are then positioned proximate the target anatomy. The anchors
613, 614 are designed to allow for fibrosis around the implantation
site in the endoscopic tunnel, thereby holding the electrodes 615,
616 in place and eliminating the need for needles and sutures. In
various embodiments, the anchors 613, 614 comprise sleeves having
grooves, spikes, or holes to allow for the ingrowth of fibrous
tissue and resultant anchoring. In another embodiment, the anchors
are narrow plastic strips having a plurality of openings for tissue
ingrowth. In another embodiment, the anchors are porous silicone
with a plurality of openings for tissue ingrowth and
neovascularization. In another embodiment, the anchors are
rosette-shaped and include a plurality of openings for tissue
ingrowth. In various embodiments, the anchors are configured to be
wide enough to perform as stoppers but are sufficiently fluffy
(porous) to prevent erosion through the esophageal wall. In one
embodiment, the anchors are comprised of silicone. In another
embodiment, the anchors 613, 614 are composed of a porous material
that promotes fibrosis and anchoring. In one embodiment, the
anchors are comprised of a Dacron mesh.
[0073] FIG. 7 is a side view illustration of one embodiment of a
lead delivery catheter 700 used to implant the needleless
electrical stimulation lead described above using the natural
orifice transluminal endoscopic surgery (NOTES) technique. The
catheter 700 includes a catheter body 711 having a proximal end, a
distal end, and a lumen within. In one embodiment, the catheter 700
has an inflatable balloon 712 attached to its distal end. The
inflatable balloon 712 is used to perform blunt dissection during
implantation. The catheter 700 also includes a grasping mechanism
713 at its distal end for grasping the lead. In one embodiment, the
grasping mechanism 713 comprises a pair of opposing grasping
members having teeth for grasping the suture loop of the lead. In
one embodiment, the catheter 700 also includes a light source 714
at its distal end for illumination of the implantation area. The
light source 714 illuminates the implantation tunnel created using
the catheter 700. In one embodiment, the catheter 700 further
includes a camera 715 at its distal end for visualization of the
implantation area. The light source 714 illuminates the tunnel so
that it can be visualized using the camera 715. In one embodiment,
the catheter 700 further includes a bipolar electrode 716 for
electrocautery of tissues as the implantation site. In one
embodiment, the bipolar electrode 716 is incorporated into the
grasping mechanism 713. The bipolar electrode 716 is used to create
a primary incision, for dissection in the implantation tunnel,
and/or for hemostasis during the implantation procedure.
[0074] The lead delivery catheter 700 can be used to implant one or
more leads via the NOTES technique using an endoscopic approach or
a laparoscopic approach. For example, when placing leads proximate
the lower esophageal sphincter (LES), an incision is made with the
catheter tip in the esophageal wall at least one inch proximal to
the LES using an endoscopic approach. Using a laparoscopic
approach, an incision is made with the catheter tip in the gastric
wall at least one inch distal to the LES. In both approaches, the
distal end of the catheter is then advanced through the incision.
Air is then pumped through the catheter lumen to inflate the
balloon attached to the distal end of the catheter. The inflated
balloon is used to create a submucosal or subserosal pocket using
blunt dissection. The distal end of the catheter is then further
advanced into the pocket and the balloon is deflated and
re-inflated to extend the pocket longitudinally, creating a tunnel
for the passage of the lead.
[0075] In the endoscopic approach, once an adequate tunnel has been
created that crosses the implant site, a second incision is made on
the contralateral side to create an exit through the
gastrointestinal wall. A laparoscopic trocar is inserted into the
abdomen with its distal end passing through the second incision.
The catheter is advanced further and the lead is passed through the
laparoscopic trocar, grasped by the grasping mechanism, and pulled
into the created tunnel. The lead is then positioned proximate the
LES. In the endoscopic approach, the lead can also be passed
through an abdominal incision directly and grasped using the
grasping mechanism of the catheter. The lead and the endoscope with
the catheter are withdrawn into the tunnel and the lead is released
once the electrodes are in the desired position proximate to the
LES muscles. In the laparoscopic approach, once an adequate tunnel
has been created that crosses the implant site, the catheter is
removed from the endoscope. The lead is then passed through a
working channel of the endoscope. The catheter is reinserted
through a laparoscopic trocar and advanced to the implant site.
Using the grasping mechanism, the physician grabs the lead which is
then positioned proximate the LES. Over time, fibrosis about the
anchors permanently fixes the lead in the tunnel with the
stimulating electrodes proximate the LES. In one embodiment,
temporary sutures or clips are used to provide temporary anchoring
support while fibrosis is setting in about the anchors. The
temporary sutures or clips are later removed after permanent
anchoring has been achieved with the lead anchors.
[0076] Optionally, in another embodiment, the lead is delivered to
the implantation site using a laparoscopic method with tunneling
from the outside inwards. This implantation is performed completely
laparoscopically without the need for an opening at the distal end
of the implantation tunnel. The physician laparoscopically creates
a dead-end tunnel proximate the target tissues. The lead is then
pushed into the blind tunnel and allowed to anchor over time.
[0077] Optionally, in another embodiment, the lead is delivered to
the implantation site via a completely endoscopic procedure. Using
an endoscope and the lead delivery catheter, the physician creates
a tunnel as described above. The lead is passed through the
endoscope and placed into position using the grasping mechanism of
the catheter.
[0078] FIG. 8 is a flowchart illustrating one embodiment of the
steps involved in implanting the needleless electrical stimulation
lead using an endoscope. The lead is of the type having the suture
material loop as described with reference to FIG. 6 above. At step
802, using the NOTES technique, a physician inserts an endoscope
into the mouth of a patient with lower esophageal sphincter (LES)
dysfunction. A lead delivery catheter as described with reference
to FIG. 7 is also inserted into a working channel of the endoscope.
At step 804, an incision is made in the wall of the lower
esophagus. The distal end of the catheter is then advanced through
the incision and into an area proximate the GEJ at step 806. At
step 808, the balloon at the distal end of the catheter is inflated
and used to create an implantation tunnel using blunt dissection.
Then, at step 810, the lead is pulled by endoscopic graspers
through a laparoscope that has been inserted into the patient's
abdomen to the tunnel created proximate the GEJ. The monopolar
branches of the lead are then positioned with the electrodes
proximate the LES at step 812. At step 814, the IS-1 connector at
the other end of the lead is attached to a pulse generator. Over
time, at step 816, fibrous tissue grows into the anchor, fixing the
lead in place.
[0079] The above examples are merely illustrative of the many
applications of the system of the present invention. Although only
a few embodiments of the present invention have been described
herein, it should be understood that the present invention might be
embodied in many other specific forms without departing from the
spirit or scope of the invention. Therefore, the present examples
and embodiments are to be considered as illustrative and not
restrictive, and the invention may be modified within the scope of
the appended claims.
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