U.S. patent application number 11/741658 was filed with the patent office on 2008-01-10 for methods for using after-loaders.
This patent application is currently assigned to WORLDWIDE MEDICAL TECHNOLOGIES LLC. Invention is credited to Edward Bleich, Warren W. Johnston, Gary A. Lamoureux, Anthony Viselli, Paul Walker.
Application Number | 20080009661 11/741658 |
Document ID | / |
Family ID | 38694681 |
Filed Date | 2008-01-10 |
United States Patent
Application |
20080009661 |
Kind Code |
A1 |
Lamoureux; Gary A. ; et
al. |
January 10, 2008 |
Methods for Using After-Loaders
Abstract
After-loader devices, kits, and methods for using the same are
provided. Such after-loader devices are useful for loading implants
into hollow needles, especially after the needles are inserted into
patient tissue. The after-loader devices can be pre-loaded with
implants, before the after-loaders are connected to hubs of hollow
needles, or loaded thereafter.
Inventors: |
Lamoureux; Gary A.;
(Woodbury, CT) ; Johnston; Warren W.; (Thomaston,
CT) ; Viselli; Anthony; (Highlands Ranch, CO)
; Walker; Paul; (Springdale, AR) ; Bleich;
Edward; (Windham, NH) |
Correspondence
Address: |
FLIESLER MEYER LLP
650 CALIFORNIA STREET
14TH FLOOR
SAN FRANCISCO
CA
94108
US
|
Assignee: |
WORLDWIDE MEDICAL TECHNOLOGIES
LLC
115 Hurley Road, Building 3
Oxford
CT
06478
|
Family ID: |
38694681 |
Appl. No.: |
11/741658 |
Filed: |
April 27, 2007 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11592909 |
Nov 3, 2006 |
|
|
|
11741658 |
Apr 27, 2007 |
|
|
|
60799161 |
May 9, 2006 |
|
|
|
60847834 |
Sep 28, 2006 |
|
|
|
Current U.S.
Class: |
600/7 |
Current CPC
Class: |
A61M 37/0069 20130101;
A61N 5/1007 20130101; A61N 2005/1008 20130101 |
Class at
Publication: |
600/007 |
International
Class: |
A61N 5/00 20060101
A61N005/00 |
Claims
1. A method for implanting an implant into patient tissue, the
method comprising: inserting a distal end of a hollow needle into
patient tissue at a desired location and to a desired depth, the
needle having a cylindrical needle hub at its proximal end;
connecting an after-loader device to the cylindrical needle hub of
the hollow needle by inserting at least a portion of the
cylindrical needle hub into a distal portion of a bore of the
after-loader, such that the after-loader is rigidly connected to
the cylindrical needle hub of the hollow needle without requiring
additional support; inserting a stylet into an opening at a
proximal end of the after-loader device; urging an implant from the
after-loader device, through a lumen of the hollow needle, to a
distal end of the hollow needle; and retracting the hollow needle
and the after-loader device, while the stylet is held in place, to
thereby deposit the implant at the desired location and to the
depth.
2. The method of claim 1, further comprising: loading the implant
into the after-loader device, after the after-loader device is
connected to the hollow needle, but before the stylet is inserted
into the after-loader device.
3. The method of claim 1, wherein the implant was loaded into the
after-loader device before the after-loader device is connected to
the hollow needle.
4. The method of claim 3, further comprising: removing end plugs of
the after-loader device, which maintain the implant within a bore
of the after-loader device, prior to connecting the after-loader
device to the hollow needle.
5. The method of claim 1, wherein the implant comprises a treatment
member that includes a plurality of radioactive sources spaced
apart from one another.
6. The method of claim 1, wherein the implant comprises a plurality
of loose seeds and spacers.
7. A method for implanting an implant into patient tissue, the
method comprising: inserting a distal end of a hollow needle into
patient tissue at a desired location and to a desired depth, the
needle having a cylindrical needle hub at its proximal end;
connecting an after-loader device to the cylindrical needle hub of
the hollow needle by inserting at least a portion of the
cylindrical needle hub into a proximal portion of a bore of the
after-loader, such that the after-loader is rigidly connected to
the cylindrical needle hub of the needle without requiring
additional support; inserting a stylet into an opening at a
proximal end of the after-loader device; urging an implant from the
after-loader device, into a lumen of the hollow needle; retracting
the stylet from the after-loader; removing the after-loader;
inserting a stylet into an opening at a distal end of the hollow
needle; urging the implant to a distal end of the hollow needle;
and retracting the hollow needle, while the stylet is held in
place, to thereby deposit the implant at the desired location and
to the depth.
8. The method of claim 7, further comprising: loading the implant
into the after-loader device, after the after-loader device is
connected to the hollow needle, but before the stylet is inserted
into the after-loader device.
9. The method of claim 7, wherein the implant was loaded into the
after-loader device before the after-loader device is connected to
the hollow needle.
10. The method of claim 9, further comprising: removing end plugs
of the after-loader device, which maintain the implant within a
bore of the after-loader device, prior to connecting the
after-loader device to the hollow needle.
11. The method of claim 1, wherein the implant comprises a
treatment member that includes a plurality of radioactive sources
spaced apart from one another.
12. The method of claim 1, wherein the implant comprises a
plurality of seeds and spacers.
13. A method for implanting an implant into patient tissue, the
method comprising: inserting a distal end of a hollow needle into
patient tissue at a desired location and to a desired depth, the
needle having a locking needle hub at its proximal end; inserting a
distal hollow shaft of an adaptor through the needle hub and into a
proximal portion of a lumen of the hollow needle; connecting an
after-loader device to a proximal hollow shaft of the adaptor;
inserting a stylet into an opening at a proximal end of the
after-loader device; urging an implant from the after-loader
device, through the adaptor, and through a lumen of the hollow
needle, to a distal end of the hollow needle; and retracting the
hollow needle and the after-loader device, while the stylet is held
in place, to thereby deposit the implant at the desired location
and to the depth.
14. The method of claim 13, further comprising: loading the implant
into the after-loader device, after the after-loader device is
connected to the hollow needle, but before the stylet is inserted
into the after-loader device.
15. The method of claim 13, wherein the implant was loaded into the
after-loader device before the after-loader device is connected to
the hollow needle.
16. A method for implanting an implant into patient tissue, the
method comprising: inserting a distal end of a hollow needle into
patient tissue at a desired location and to a desired depth, the
needle having a locking needle hub at its proximal end; inserting a
distal hollow shaft of an adaptor through the needle hub and into a
proximal portion of a lumen of the hollow needle; connecting an
after-loader device to a proximal hollow shaft of the adaptor;
inserting a stylet into an opening at a proximal end of the
after-loader device; urging an implant from the after-loader
device, through the adaptor, and into a lumen of the hollow needle;
retracting the stylet from the after-loader; removing the
after-loader and the adaptor; inserting a stylet into an opening at
a distal end of the hollow needle; urging the implant to a distal
end of the hollow needle; and retracting the hollow needle, while
the stylet is held in place, to thereby deposit the implant at the
desired location and to the depth.
17. The method of claim 16, further comprising: loading the implant
into the after-loader device, after the after-loader device is
connected to the hollow needle, but before the stylet is inserted
into the after-loader device.
18. The method of claim 16, wherein the implant was loaded into the
after-loader device before the after-loader device is connected to
the hollow needle.
Description
PRIORITY CLAIM
[0001] This application is a continuation-in-part (CIP) of and
claims priority to U.S. patent application Ser. No. 11/592,909,
filed Nov. 3, 2006, which is entitled AFTER-LOADER FOR POSITIONING
IMPLANTS FOR NEEDLE DELIVERY IN BRACHYTHERAPY AND OTHER RADIATION
THERAPY (Attorney Docket No. WORLD-01026US2), and which is
incorporated herein by reference.
[0002] This U.S. patent application also claims priority under 35
U.S.C. 119(e) to U.S. Provisional Patent Application No.
60/799,161, which was filed May 9, 2006, and U.S. Provisional
Patent Application No. 60/847,834, which was filed Sep. 28, 2006,
each of which is entitled AFTER-LOADER FOR POSITIONING IMPLANTS FOR
NEEDLE DELIVERY IN BRACHYTHERAPY AND OTHER RADIATION THERAPY, and
each of which is incorporated herein by reference.
CROSS REFERENCE TO RELATED APPLICATION
[0003] This application relates to U.S. patent application Ser. No.
11/______, filed Apr. 27, 2007, which is entitled AFTER-LOADER
DEVICES AND KITS (Attorney Docket No. WORLD-01026US3).
FIELD OF THE INVENTION
[0004] This invention relates to devices and methods that are used
for transferring implants to needles used in brachytherapy.
BACKGROUND
[0005] Brachytherapy is a general term covering medical treatment
which involves placement of radioactive sources near a diseased
tissue and can involve the temporary or permanent implantation or
insertion of radioactive sources into the body of a patient. The
radioactive sources are located in proximity to the area of the
body which is being treated. A high dose of radiation can thereby
be delivered to the treatment site with relatively low doses of
radiation to surrounding or intervening healthy tissue. Exemplary
radioactive sources include radioactive seeds, radioactive rods and
radioactive coils.
[0006] Brachytherapy has been used or proposed for use in the
treatment of a variety of conditions, including arthritis and
cancer. Exemplary cancers that can be treated using brachytherapy
include breast, brain, liver and ovarian cancer and especially
prostate cancer in men. For a specific example, treatment for
prostate cancer can involve the temporary implantation of
radioactive sources (e.g., rods) for a calculated period, followed
by the subsequent removal of the radioactive sources.
Alternatively, radioactive sources (e.g., seeds) can be permanently
implanted in the patient and left to decay to an inert state over a
predictable time. The use of temporary or permanent implantation
depends on the isotope selected and the duration and intensity of
treatment required.
[0007] Permanent implants for prostate treatment include
radioisotopes with relatively short half lives and lower energies
relative to temporary seeds. Exemplary permanently implantable
sources include iodine-125, palladium-103 or cesium-131 as the
radioisotope. The radioisotope can be encapsulated in a
biocompatible casing (e.g., a titanium casing) to form a "seed"
which is then implanted. Temporary implants for the treatment of
prostate cancer may involve iridium-192 as the radioisotope. For
temporary implants, radioactive rods are often used.
[0008] Conventional radioactive seeds are typically smooth sealed
containers or capsules of a biocompatible material, e.g., titanium
or stainless steel, containing a radioisotope within the sealed
chamber that permits radiation to exit through the
container/chamber walls. Other types of implantable radioactive
sources for use in radiotherapy are radioactive rods and
radioactive coils, as mentioned above.
[0009] Preferably, the implantation of radioactive sources for
brachytherapy is carried out using minimally-invasive techniques
such as, e.g., techniques involving hollow needles. It is possible
to calculate a desired location for each radioactive source which
will give the desired radiation dose profile. This can be done
using knowledge of the radioisotope content of each source, the
dimensions of the source, accurate knowledge of the dimensions of
the tissue or tissues in relation to which the source is to be
placed, plus knowledge of the position of the tissue relative to a
reference point. The dimensions of tissues and organs within the
body for use in such dosage calculations can be obtained prior to
or during placement of the radioactive sources by using
conventional diagnostic imaging techniques including X-ray imaging,
magnetic resonance imaging (MRI), computed tomography (CT) imaging,
fluoroscopy and ultrasound imaging.
[0010] During the placement of the radioactive sources into
position, a surgeon can monitor the position of tissues such as the
prostate gland using, e.g., ultrasound imaging or fluoroscopy
techniques which offer the advantage of low risk and convenience to
both patient and surgeon. The surgeon can also monitor the position
of the relatively large needle used in implantation procedures
using ultrasound or other imaging.
[0011] As mentioned above, brachytherapy typically employs hollow
needles that are insertable into a patient's body, often with the
assistance of a template. A typical template used to guide and/or
inform the positioning of hollow needles at a surgical site can
provide access to more than one hundred locations. The number of
locations can be so numerous that a typical pitch between needle
access points can include a pitch of 5 mm.
[0012] A hollow needle, as explained above, is used to implant
radioactive sources and/or other types of treatment elements into
patient tissue at a desired location and to a desired depth. Such
treatment elements, which are implantable using the hollow needle,
shall be collectively referred to as an implant. Such an implant
can be an elongate treatment member, such as a strand that includes
a plurality of radioactive sources (e.g., seeds) spaced apart from
one another within a bioabsorbable material. Besides a strand, an
implant can be another type of treatment member that includes a
plurality of radioactive sources spaced apart from one another,
such as a member formed of seeds and spacers that are frictionally
or otherwise connected to one another (e.g., as described in U.S.
Pat. Nos. 6,010,446 and 6,450,939, which are incorporated herein by
reference). An elongate treatment member may also be made from a
hollow tube that includes a plurality of seeds and spacers loaded
within a bore of the tube, with the tube possibly heat shrunk
around the seeds and spacers, or the ends of the tube otherwise
closed. Alternatively, an implant can be a plurality of loose seeds
and loose spacers axially aligned one behind the other. It is also
possible that the implant be a single loose radioactive source.
Other possibilities also exist, as would be appreciated by one of
ordinary skill in the art. For example, an implant can include one
or more radioactive rod or coil. An implant can also include one or
more seed that has anchoring mechanisms, exemplary details of which
are provided in commonly assigned U.S. patent application Ser. No.
11/187,411, entitled "Implants for Use in Brachytherapy and Other
Radiation Therapy That Resist Migration and Rotation," filed Jul.
22, 2005. Alternatively, the implant can be or include some other
object and need not be radioactive, e.g. a spacer, a marker, or a
thermal seed that gives off heat.
[0013] Various types of hollow needles can be used in
brachytherapy, examples of which are shown in FIGS. 1A and 1B. A
first type of needle, shown in FIG. 1A, is often referred to as an
applicator needle, and is sometimes marketed under the trademark
MICK.RTM. needle. Referring to FIG. 1A, an applicator needle 102a
is shown as including a hollow needle 104a (also referred to as a
cannula) with a blunt or un-sharpened distal end 106a, and a hub
108a positioned at a proximal end. The hub 108a, as shown, has a
generally simple cylindrical shape. An exemplary length of the
entire needle 102a including the hub is about 77/8 inches (about 20
cm), with the hub 108a having a length of about 1 inch (about 2.5
cm). As shown in FIG. 1A, the hub 108a surrounds a proximal portion
of the cannula 104a. A bore 110a (also referred to as a lumen)
extends through the applicator needle 102a. An exemplary diameter
of the bore 110a (i.e., the inner diameter of the cannula 104a) is
about 0.042 inches.
[0014] When an applicator needle 102a is used in brachytherapy, a
sharp stylet (not shown) is inserted through the lumen 110a of the
hollow needle, so that the sharp distal end of the sharp stylet
(e.g., a trocar tip) extends past the blunt distal end 106a of the
applicator needle 102a. The needle 102a, with the sharp stylet
point extending out its blunt distal end 106a, can then be inserted
into patient tissue at a desired location, including to a desired
depth. Thereafter, the sharp stylet is removed, and an implant
(e.g., a strand, seeds and spacers, or combinations thereof) is
loaded into the needle through the proximal end of the needle.
Tweezers or the like can be used to insert a strand or other
treatment member, and/or loose seeds and spacers, into the proximal
end of the needle. However, this can be very difficult and time
consuming due to the small inner diameter of the hollow needle. A
blunt ended stylet (not shown) can then be inserted into the
proximal opening of the needle 102a, until the distal end of the
stylet contacts the proximal end of the treatment member (or most
proximal seed or spacer). The needle can then be retracted with the
stylet held in position so that the implant is deposited at a
desired location.
[0015] Alternatively, an applicator device, such as a MICK.RTM.
applicator, can be attached to the proximal end of the applicator
needle 102a, and the applicator device can be used to dispose loose
seeds (and optionally loose spacers) through the needle 102a and
into patient tissue. The MICK.RTM. applicator is available from
Mick Radio-Nuclear Instruments, Inc., Mount Vernon, N.Y. Details of
the MICK.RTM. applicator are provided in U.S. Pat. No.
5,860,909.
[0016] Referring now to FIG. 1B, a second type of needle 102b,
which shall be referred to herein as a locking hub needle for
reasons that will be apparent (and sometimes referred to as a
prostate seed needle, a standard needle, or a seed lock needle),
includes a cannula 104b, a sharpened distal end 106b (e.g., a
beveled end), and a hub 108b positioned at a proximal end. The hub
108b has an enlarged diameter with a funneled proximal portion 112,
and threads 114 on an outer circumference, that may be used, e.g.,
to connect the hub 108b to a syringe. The funneled distal end 112
allows a more forgiving tolerance for inserting implants into a
lumen 110b of the cannula 104b (if tweezers or the like are used to
insert a treatment member and/or loose seeds and spacers into the
proximal end of the needle). Nevertheless, even though the proximal
funneled opening of needle 102b is larger then the proximal opening
of needle 102a, it can still be very difficult and time consuming
to load an implant into the needle 102b.
[0017] Such needles 102b are typically plugged at the distal end
with bonewax or some other plugging material, and pre-loaded with a
treatment member and/or loose seeds and spacers, prior to the
needle 102b being inserted into patient tissue. Alternatively, such
needles 102b can be loaded (i.e., after-loaded) with a treatment
member and/or loose seeds and spacers after the needle 102b is
inserted into patient tissue.
[0018] An exemplary length of the entire needle 102b, including the
hub, is about 87/8 inches (about 22.5 cm). An exemplary length of
the hub 108b is about 1 inch (about 2.5 inches). Here, only a
portion of the hub 108a surrounds a proximal portion of the cannula
104b, so that the funneled portion 112 can have a larger diameter
than the diameter of the cannula 104b. An exemplary diameter of the
bore 110b (i.e., the inner diameter of the cannula 104b) is about
0.042 inches.
[0019] It has generally been difficult and time consuming for
physicians to load a hollow needle (e.g., 102a or 102b) with a
treatment member and/or loose seeds and spacers, especially after
the needle has been inserted into patient tissue. It would be
beneficial if devices and methods were provided for simplifying and
expediting such procedures.
SUMMARY OF EMBODIMENTS OF THE INVENTION
[0020] Embodiments of the present invention relate to devices,
referred to as after-loader devices, that are useful for loading an
implant into a hollow needle after the needle is inserted into
patient tissue. Embodiments of the present invention also relate to
kits that include such after-loader devices, as well as methods for
using after-loader devices.
[0021] In accordance with specific embodiments, an after-loader
device is especially useful for a connecting to a hollow needle,
known as an applicator needle, which has a simple cylindrical
needle hub at the proximal end of the needle. The after-loader
includes an elongated body having a proximal end and a distal end,
with a bore extending axially through the body between the proximal
and distal ends. A main portion of the bore has a first inner
diameter that is approximately equal to the inner diameter of the
hollow needle to which the after-loader attaches. A distal portion
of the bore has a second inner diameter that is larger than the
outer diameter of the needle hub, with the distal portion of the
bore being configured to connect to the cylindrical needle hub of
the hollow needle. In accordance with an embodiment, a depth of the
distal portion of the bore is sufficient to enable the body of the
after-loader device to rigidly connect to the cylindrical needle
hub of the hollow needle without requiring additional support. A
proximal portion of the bore can be funneled to assist with
inserting an implant and/or a stylet into the bore.
[0022] In accordance with specific embodiments, the after-loader
device includes a radiation shield configured to slide over an
outer circumferential surface of a main portion of the body, to
thereby cover the main portion of the body. The body of the
after-loader can be translucent or transparent so that a user can
observe an implant loaded into the bore, when the radiation shield
is at least partially removed.
[0023] In accordance with specific embodiments, a distal portion of
the body of the after-loader has an outer diameter that is greater
than an outer diameter of the main portion of the body, and greater
than an inner diameter of the radiation shield. Such distal portion
of the body provides a stop for the radiation shield, and also
accommodates the distal portion of the bore. Additionally, a
tapered outer circumference, that extends between the distal
portion of the body and the main portion of the body, can provide a
friction fit between the body and the radiation shield.
[0024] In accordance with specific embodiments, the after-loader
device includes a distal end plug to plug a distal opening of the
bore, and a proximal end plug to plug a proximal opening of the
bore. The distal end plug and the proximal end plug, when
respectively plugged into the distal and proximal openings of the
bore, prevent an implant loaded in the bore from falling out of the
bore. Such end plugs can each include a gripping portion and an
insertion portion, and can be made from a radiation blocking
material.
[0025] In accordance with an embodiment, a tapered nose at the
distal end of the body is configured to fit into a hub of a second
type of hollow needle, such as a locking hub needle.
[0026] In further embodiments of the present invention, the
after-loader device includes an adapter for use in connecting the
body of the after-loader device to a second type of hollow needle,
such as a locking hub needle. Such an adaptor can include a central
portion, a distal hollow shaft and a proximal hollow shaft. The
distal hollow shaft is for insertion into a hub of the second type
of needle and into a proximal most portion of a lumen of the second
type of needle. The proximal hollow shaft if for insertion into the
distal portion of the bore of the body of the after-loader device.
The central portion of the adaptor can includes inner threads, for
engaging threads on the hub of the second type of needle.
[0027] Embodiments of the present invention are also related to
brachytherapy kits. Such a kit can include a plurality of
after-loader devices, each of which is useful for loading an
implant into a hollow needle after the needle is inserted into
patient tissue. The kit can also include a plurality of treatment
members, each member loaded into a bore of one of the after-loader
devices, and maintained in the bore by end-plugs of the
after-loader device. Each such member (e.g., a strand) can include
a plurality of radioactive sources spaced apart from one another,
e.g., in accordance with a treatment plan. Alternatively, or
additionally, an implant loaded into a bore can include a plurality
of loose seeds separated from one another by spacers. Each the
after-loader device of the kit can include a radiation shield that
surrounds at least a main portion of the body of the after-loader
device. Also, the kit can include at least one stylet having a
length that is at least as long as a total length of the
after-loader device connected with a hollow needle, as well as at
least one hollow needle. In specific embodiments, the plurality of
treatment members of the kit fulfill an entire predetermined
treatment plan for a patient. The kit can also include a tray
holding the plurality of after-loader devices loaded with the
plurality of treatment members, as well as a pouch housing the tray
(which is holding the plurality of after-loader devices loaded with
the plurality of treatment members). Additionally, depending on the
type of hollow needle included in the kit, the kit can also include
at least one adaptor configured to connect the after-loader devices
to hub of a locking hub hollow needle.
[0028] Embodiments of the present invention are also directed to
methods for implanting implants into patient tissue. In accordance
with an embodiment, a distal end of a hollow needle is inserted
into patient tissue at a desired location and to a desired depth.
Where the hollow needle does not have a sharpened end, a sharp end
of a sharp stylet is extended beyond the distal end of the hollow
needle, to assist with the insertion of the needle. Where the
needle has a sharpened distal end, such a sharpened stylet need not
be used.
[0029] Where the needle hub is a simple cylindrical needle hub of a
hollow needle known as an applicator needle, the after-loader
device can be connected to the cylindrical needle hub by inserting
at least a portion of the cylindrical needle hub into a distal
portion of a bore of the after-loader, such that the after-loader
is rigidly connected to the cylindrical needle hub of the hollow
needle without requiring additional support. A stylet is inserted
into an opening at a proximal end of the after-loader device, to
urge an implant from the after-loader device into a lumen of the
hollow needle.
[0030] Certain embodiments employ the use of a stylet having a
length that is at least as long as a total length of the
after-loader device connected with a hollow needle. Where such a
stylet is available, the implant can be urged from the after-loader
device, through a lumen of the hollow needle, to a distal end of
the hollow needle, while the after-loader device is still connected
to the needle. Thereafter, the hollow needle and the after-loader
device are retracted, while the stylet is held in place, to thereby
deposit the implant at the desired location and to the depth.
[0031] In specific embodiments, the implant can be loaded into the
bore of the after-loader device, after the after-loader device is
connected to the hollow needle, but before the stylet is inserted
into the after-loader device. In other embodiments, the implant was
already loaded into the bore of the after-loader device before the
after-loader device is connected to the hollow needle.
[0032] In specific embodiments, where the after-loader device
includes end plugs, the end plugs of the after-loader device, which
maintain the implant within a bore of the after-loader device, are
removed prior to connecting the after-loader device to the hollow
needle.
[0033] In specific embodiments the implant is a treatment strand or
other treatment member, which includes a plurality of radioactive
sources spaced apart from one another. Alternatively, or
additionally, the implant can be a plurality of loose seeds and
spacers. Other implants are also possible, as described below.
[0034] Where the stylet to be employed is not as long as a total
length of the after-loader device connected with a hollow needle,
the stylet is used to urging an implant from the after-loader
device, into a lumen of the hollow needle. The stylet is then
retracted from the after-loader, and the after-loader is removed,
i.e., disconnected from the hollow needle. Thereafter, a stylet
(the same or a different stylet) is inserted into an opening at a
distal end of the hollow needle, and the stylet is used to urge the
implant to a distal end of the hollow needle. Then, the hollow
needle is retracted while the stylet is held in place, to thereby
deposit the implant at the desired location and to the depth.
[0035] Methods of the present invention also include methods that
used the adaptor mentioned above. For example, after a distal end
of a hollow needle is inserted into patient tissue, a distal hollow
shaft of an adaptor can be inserted through the needle hub and into
a proximal portion of a lumen of the hollow needle, and an
after-loader device can be connected to a proximal hollow shaft of
the adaptor. It is also possible that the adaptor, just described,
already be connected to the proximal portion of a hollow needle,
when the distal end of the hollow needle is inserted into patient
tissue. A stylet can then be inserted into an opening at a proximal
end of the after-loader device. Depending upon the length of the
stylet, the after-loader body and adaptor may be left in place
during the remainder of the implant procedure, or may need to be
removed before a stylet is used to urge the implant to the distal
end of the hollow needle. The hollow needle (and the after-loader
device and adaptor, if still in place) are then retracted, while
the stylet is held in place, to thereby deposit the implant at the
desired location and to the depth.
[0036] This summary is not intended to be a complete description of
the invention. Other features, aspects, objects and advantages of
the invention can be obtained from a review of the specification,
the figures, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1A is a side view of first type of hollow brachytherapy
needle, often referred to as an applicator needle.
[0038] FIG. 1B is a side view of a second type of hollow
brachytherapy needle, sometime referred to as a seed lock needle,
or a locking hub needle.
[0039] FIG. 2A is a side view of an after-loader in accordance with
an embodiment of the present invention, with its shield
removed.
[0040] FIG. 2B is a side view of the after-loader device of FIG.
2A, with its shield in place.
[0041] FIG. 2C is a perspective view of the after-loader device of
FIGS. 2A & 2B, with its shield removed.
[0042] FIG. 2D is a perspective view of the shield of the
after-loader device.
[0043] FIG. 3A is a cross-sectional side view of the after-loader
of FIG. 2A mated with the needle of FIG. 1A, and having a stylet
disposed within the after-loader device and hollow needle.
[0044] FIG. 3B is a cross-sectional side view of the after-loader
of FIG. 2A mated with the hollow needle of FIG. 1B, and having a
stylet disposed within the after-loader device and hollow
needle.
[0045] FIG. 4A is a perspective view of an adaptor, according to an
embodiment of the present invention, which can be used to help
connect the after-loader device of FIGS. 2A & 2B to the hollow
needle of FIG. 1B.
[0046] FIG. 4B is a cross-sectional view of the adaptor of FIG.
4A.
[0047] FIG. 4C is a cross-sectional side view of the after-loader
device of FIG. 2A mated with the hollow needle of FIG. 1B, using
the adapter of FIGS. 4A and 4B, and having a stylet disposed within
the bore of the after-loader and adaptor and the hollow needle.
[0048] FIG. 5A is a side view of a distal end plug for an
after-loader, in accordance with an embodiment of the present
invention.
[0049] FIG. 5B is a side view of a proximal end plug for an
after-loader, in accordance with an embodiment of the present
invention.
[0050] FIG. 5C is a side view of the after-loader of FIGS. 2A-2C
(without its shield) with the distal and proximal end plugs of
FIGS. 5A and 5B in place.
[0051] FIG. 6A is a side view of a distal end plug for an
after-loader, in accordance with another embodiment of the present
invention.
[0052] FIG. 6B is a side view of a proximal end plug for an
after-loader, in accordance with another embodiment of the present
invention.
[0053] FIG. 7 shows a plurality of after-loaded devices within a
tray.
[0054] FIG. 8 is a high level flow diagram that is used to
summarize a method of using an after-loader, in accordance with an
embodiment of the present invention.
[0055] FIG. 9 is a high level flow diagram that is used to
summarize a method of using an after-loader, in accordance with an
alternative embodiment of the present invention.
DETAILED DESCRIPTION
[0056] As explained above, it has generally been difficult and time
consuming for physicians to load a hollow needle (e.g., 102a or
102b) with a strand and/or loose seeds and spacers, especially
after the needle has been inserted into patient tissue. As will be
described below, embodiments of the present invention related to
devices and methods for simplifying and expediting such procedures.
More specifically, embodiments of the present invention relate to
devices, referred to as after-loader devices, that are useful for
loading an implant into a hollow needle after the needle is
inserted into patient tissue. Embodiments of the present invention
also relate to kits that include such after-loader devices, as well
as methods for using after-loader devices.
[0057] As will be described below, an after-loader of the present
invention can simplify and/or expedite the loading of an implant
into a hollow needle, especially after the needle has been inserted
into patient tissue. It is because such a device is useful in
loading a hollow needle "after" the needle is inserted into patient
tissue, that the device is referred to herein as an "after-loader".
Nevertheless, the after-loader device can also be used to pre-load
a needle (i.e., load an implant into a hollow needle before the
needle is inserted into patient tissue), if desired.
[0058] Referring to FIG. 2A, an after-loader device 202, according
to an embodiment of the present invention, is shown. FIG. 2C shows
a perspective view of the after-loader device 202, which is also
referred to simply as an after-loader 202. The after-loader 202 can
be used with the applicator needle 102a of FIG. 1A (as shown in
FIG. 3A), or alternatively with the locking hub needle 102b of FIG.
1B (as shown in FIGS. 3B and 4C), providing flexibility in needle
choice. The after-loader 202 includes an elongated body 204 having
a distal end 206, a proximal end 208, with a bore 210 extending
therebetween. The body 204 of the after-loader 202 is shown as
having a generally cylindrical shape, however variations on this
are possible.
[0059] The body 204 of the after-loader 202, or the after-loader
202 in general, includes a distal portion 212, a main portion 214
and a proximal portion 216. In accordance with an embodiment, the
main portion 214 of the after-loader 202 includes a generally
constant outer diameter (e.g., 0.162 inches), and a generally
constant inner diameter (e.g., 0.055 inches), with the inner
diameter being about the same as the inner diameter of the needle
with which the after-loader 202 will interface (as mentioned above,
the inner diameter of the cannula of the hollow needles 102a and
102b can be about 0.042 inches). More generally, the diameter of
the bore 210 that extends through the main portion 214 of the
after-loader 202 should be slightly larger than the outer diameter
of the implant (e.g., strand, seed(s) and/or spacer(s)) that is to
be loaded into the after-loader 202. In certain embodiments, the
inner diameter of the bore 210 of the main portion 214 of the
after-loader 202 can have one or more step, and/or have a taper
(rather than having a constant inner diameter), such that the
proximal end of the bore 210 within the main portion 214 has a
slightly larger diameter than the distal end of the bore 210 within
the main portion 214.
[0060] In the embodiment shown, the distal portion 212 of the
after-loader 202 includes an enlarged outer diameter (e.g., 0.188
inches), which tapers at each end. More specifically, at the
proximal end of the distal portion, the distal portion 212 tapers
at a small angle .theta. (e.g., 5 degrees) until the diameter of
the main portion 214 of the body 204 (e.g., 0.162 inches) is
reached. The purpose of this taper 219 is to provide a friction fit
for a shield 250 that slides over the rest of the after-loader 202,
the friction fit being attributable to the increase in diameter
toward the distal portion 210. The shield 250 is positioned around
the after-loader 202 to reduce or minify an amount of radiation
that escapes from the after-loader 202 where implants placed in the
after-loader 202 are radioactive. FIG. 2B shows the after-loader
202 with its shield 250 in place. FIG. 2D shows a perspective view
of the shield 250.
[0061] Referring to FIGS. 2A and 2C, the taper at the distal end of
the distal portion 212 forms a nose 218 of the after-loader 202,
which is tapered at an angle .alpha. generally corresponding to an
angle of the funneled proximal portion 112 of the locking hub
needle 102b. Thus, an external angle of the nose 218 can be
approximately 15 degrees in angle, in an embodiment wherein a
typical locking hub needle 102b is to be accommodated. The nose 218
of the after-loader 202 can be positioned within the funneled
portion 112 of the locking hub needle 102b, so that the
after-loader 202 is removably mated with the hub 108b of the
locking hub needle 102b, as can be appreciated from FIG. 3B,
discussed in more detail below. It is also possible that an
after-loader 202 not include a tapered nose 218.
[0062] A funneled portion 230 of the bore 210 of the after-loader
202 can be funneled at an angle .beta. to simplify insertion of an
implant and stylet into the bore 210 of the after-loader 202. For
example, the funnel can cause an increase in diameter at a 5 to 10
degree angle, and specifically at an 8 degree angle. Such funneled
portion 230 of the bore 210 extends through the proximal portion
216 of the body 204.
[0063] In accordance with an embodiment, the body 204 of the
after-loader 202 can be made of a transparent or translucent
material, such as a medial grade plastic, e.g., acrylic,
polycarbonate or other plastic, that enables a user (e.g.,
physician, clinician, physicist, etc.) to visually verify the
contents (i.e., implant) loaded in the after-loader 202. Where the
after-loader 202 is made of a plastic, the after-loader 202 may not
sufficiently restrict radiation from escaping the after-loader 202.
Accordingly, the shield 250 is employed to reduce and preferably
prevent leakage. As shown in FIG. 2D, the shield 250 can be a
hollow cylinder formed of a material (e.g., stainless steel) that
sufficiently restricts the amount of radiation that escapes the
shield 250. In such embodiments, the shield 250 can be slid back
(i.e., toward the proximal end of the after-loader 202) to reveal
the contents of the after-loader 202, for visual verification
purposes. In other embodiments, the after-loader 202 itself can be
made from a material more opaque to radiation, such as stainless
steel, or a plastic impregnated with lead, or some other shielded
plastic.
[0064] Referring to FIGS. 2A-2C, the enlarged outer diameter of the
distal portion 212 of the after-loader 202 serves two purposes.
First, it enables the diameter of a distal portion 220 of the bore
210 to be enlarged to accommodate the hub 108a of the applicator
needle 102a, as discussed in more detail below. Further, it acts as
a stop to hold the shield 250 in place at the proper location after
the shield 250 has been slid over the proximal end 208 of the
after-loader 202.
[0065] In accordance with an embodiment, the inner diameter of the
distal portion 212 of the after-loader 202 is larger than the inner
diameter of the main portion 214 of the after-loader 202, so that
the hub 108a of the applicator needle 102a can be accepted therein.
In other words, the diameter of the distal portion 220 of the bore
210 (which is the portion of the bore 210 within distal portion
212) is larger than the diameter of the main portion of the bore
210 (i.e., the portion of the bore 210 extending through the main
portion 214 of the body 204). More specifically, the distal opening
of the portion 220 of the bore 210, extending from the distal end
206 towards the proximal end 208 of the body 204, has a diameter
that is slightly larger than the outer diameter of the hub 108a of
the applicator needle 102a, so that the distal portion 220 of bore
210 is configured to receive, and thereby connect to, the hub 108a
of the applicator needle 102a. For example, the diameter of the
distal portion 220 of the bore 210 can be 0.099 inches, while the
diameter of the main portion of the bore 210, which roughly
corresponds to the inner diameter of a hollow needle, can be from
anywhere from about 0.042 to 0.055 inches. In specific embodiments,
the distal portion 220 of the bore 210 has a slight taper from its
opening rearward (e.g., an opening diameter of 0.105 inches tapers
to 0.985 inches), so that a slight friction fit can be provided
between the distal portion 220 of the bore 210 and the hub 108a
accepted therein (presuming the outer diameter of the hub 108a is
less than 0.105 inches, but greater than 0.985 inches).
[0066] Additionally, a depth d of the distal portion 220 of the
bore 210 is preferably sufficient to enable the body 204 of the
after-loader 202 to rigidly connect to the hub 108a of the needle
102a without requiring any additional support, e.g., from a user or
some support structure (e.g., a support rod). Preferably such depth
d is at least 1/4 inch, and more preferably about 1/2 inch.
However, other depths will work, and are within the scope of the
present invention.
[0067] FIG. 3A shows a cross-section of the after-loader 202
accepting the hub 108a of an applicator needle 102a. FIG. 3A also
shows a stylet 302, including a handle 304 at its proximal end,
inserted through the bore 210 of the after-loader 202 and the lumen
110a of the applicator needle 102a. As mentioned above, the
diameter of the distal portion 220 of the bore 210 of the
after-loader is slightly larger than the outer diameter of the hub
108a, so the hub 108a fits therein.
[0068] FIG. 3B shows a cross-section of the after-loader 202 with
its nose 218 within the funneled portion 112 of a locking hub
needle 102b. FIG. 3A also shows a stylet 302, including a handle
304 at its proximal end, inserted through the bore 210 of the
after-loader 202 and the lumen 110b of the locking hub needle 102b.
When used in the manner shown in FIG. 3B, the after-loader 202 may
need to be supported by the user, to prevent the after-loader from
disengaging from the hub 108b of the needle 102b. To ensure that no
such user support is needed, an adaptor 402 of an embodiment of the
present invention can be used, as will now be explained with
reference to FIGS. 4A-4C.
[0069] FIG. 4A is a perspective view of the adaptor 402, in
accordance with an embodiment of the present invention. FIG. 4B is
a cross-section of the adaptor 402. The adaptor 402 includes a
central portion 404, from which extends a distal hollow shaft 406
and a proximal hollow shaft 408. The hollow shafts 406 and 408 can
be discontinuous (i.e., separate from one another), as shown in
FIG. 4B. Alternatively, the distal and proximal shafts 406 and 408
can be parts of a continuous shaft that extends through the central
portion 404. A bore 410 extends axially through the entire adaptor
402, whether or not the shafts 406 and 408 are continuous. The
diameter of the bore 410 should be sufficient to allow an implant
to pass there-through. Thus, the diameter of the bore 410 can be
similar to the diameter of the bores 110a and 110b of needles 102a
and 102b, which can be similar to the diameter of the major portion
of the bore 210 of the after-loader 202 as discussed above.
[0070] Referring to FIG. 4C, the distal hollow shaft 406 of the
adaptor 402 is intended to fit within the proximal end of hub 108b
of locking hub needle 102b, and into a most proximal portion of the
lumen 110b of the cannula 104b. Additionally, the central portion
404 can include inner threads 414 to engage the outer threads 114
of the hub 108b of the locking hub needle 102b. An outer
circumference 412 of the central portion 404 can be textured, to
make it easier for a user to turn the adaptor 402 so it screws onto
threads 114 of the hub 108b. The proximal hollow shaft 408 is
intended to fit in the enlarged distal portion 220 of the bore 210
of the after-loader 202.
[0071] One or more empty after-loader 202 can be provided to a
user, so that the user can load each after-loader 202 with an
implant and thereafter use the after-loader(s) 202 during an
brachytherapy procedure. In another embodiment, one or more already
loaded after-loader 202 (i.e., a pre-loaded after-loader) can be
provided to a user. More specifically, a facility can load implants
into a plurality of after-loaders 202, and provide such pre-loaded
after-loaders to a user. The pre-loaded after-loaders 202 can
include all the implants that are necessary to fulfill a
predetermined patient specific treatment plan. In specific
embodiments, each after-loader is pre-loaded with a corresponding
strand or other treatment member that has been manufactured to meet
a treatment plan. Such pre-loaded after-loaders 202 can be
delivered in a tray having a unique number for each of the
pre-loaded after-loaders 202, so that the user knows which strand
or other member is located in which after-loader, and thus knows,
where each strand or other member should be implanted. It is also
possible that such numbers or similar designations are printed
directly on the after-loaders 202. When pre-loaded after-loaders
202 are provided to a user, it is preferred that each pre-loaded
after-loader 202 is covered by its shield 250. Also, the packaging
that is used to store the plurality of pre-loaded after-loaders can
include further shielding, e.g., a lead plate can cover a row of
pre-loaded after-loaders that are within a tray.
[0072] When the after-loader 202 is shipped pre-loaded with a
treatment member (e.g., strand), or other implant, the openings at
the proximal and distal ends 206 and of the after-loader 202 are
preferably plugged, to prevent the treatment member or other
implant from unintentionally falling out of the after-loader 202.
Referring to FIG. 5A, a distal end plug 502, according to an
embodiment of the present invention, is shown. FIG. 5B shows a
proximal end plug 512, according to an embodiment of the present
invention.
[0073] FIG. 5C shows a side view of a pre-loaded after-loader 202,
which is pre-loaded with a strand 502. The strand 522 includes a
plurality of radioactive seeds 524 that are spaced apart from one
another, e.g., in accordance with a treatment plan. A cut-away view
of the shield 250 is provided, so that it can be seen that the
strand 522 is within the bore 210 of the after-loader 202. The
opening at the distal end 206 of the after-loader 202 is plugged
with the distal end plug 502. Similarly, the opening at the
proximal end 208 of the after-loader 202 is plugged with the
proximal end plug 512. In addition to preventing a treatment member
(e.g., strand) or other implant from falling out of the
after-loader 202, the end plugs 502 and 512 can also be employed to
block radiation from emitting from the ends of the after-loader
202. If that is desired, the end plugs 502 and 512 should be made
of a material that blocks radiation, e.g., stainless steel.
Alternatively, the end plugs 502 and 512 need not block radiation,
and can be made of plastic or the like.
[0074] The distal end plug 502 includes a grip portion 504, that
can be gripped to insert the insertion portion 506 of the distal
end plug 502 into the opening at the distal end 206 of the
after-loader 202. The diameter of the grip portion 504 is greater
than the diameter of the distal portion 220 of the bore 210. The
diameter of the insertion portion 506 of the distal end plug 502 is
sized so that it fits within the distal portion 220 of the bore
210, yet creates a friction fit so the end plug 502 does not
inadvertently fall out. In accordance with an embodiment, a length
or depth of the insertion portion 506 of the distal end plug 502 is
about the same as the depth of the distal portion 220 of the bore
210. This will keep the distal end of the treatment member (e.g.,
strand) or other implant within the confines of the shield 250.
[0075] Similarly, the proximal end plug 512 includes a grip portion
514, that can be gripped to insert the insertion portion 516 of the
proximal end plug 512 into the opening at the proximal end 208 of
the after-loader 202. The diameter of the grip portion 514 is
greater than the largest diameter of the funneled portion 230 of
the bore 210. The diameter of the insertion portion 516 of the
proximal end plug 512 is sized so that it fits within the funneled
portion 230 of the bore 210, yet creates a friction fit so the end
plug 512 does not inadvertently fall out. In accordance with an
embodiment, a length or depth of the insertion portion 516 of the
proximal end plug 512 is about the same as the depth from the
proximal end 208 to the most distal point of the funnel 230. This
will keep the proximal end of the treatment member (e.g., strand)
or other implant within the confines of the shield 250.
[0076] It should be noted that the end plugs 502 and 512 need not
be shaped as shown in FIGS. 5A and 5B. The end plugs need only be
shaped so as to function to maintain the implant within the
after-loader 202. For example, where radiation emission from the
implant is not a concern, the end plug need not function to block
radiation. Alternative designs for the end plugs are shown in FIGS.
6A and 6B, which, respectively, show an alternative distal and plug
602 and alternative proximal end plug 612. Instead of using end
plugs, or in addition to using end plugs, an elongate treatment
member (that is loaded within the bore 210 of the after-loader 202)
can include one or more bumps, rings, wings, polymeric hairs or
other protrusions that frictionally maintains the member within the
bore 210, until the member is urged out using a stylet.
[0077] FIGS. 4A, 5B, 6A and 6B illustrate exemplary embodiments of
end plugs for use with after-loaders 202. In other embodiments,
some other style of end plugs can be employed to retain an implant
with an after-loader 202. In still other embodiments, end plugs for
use with the after-loader of the present invention can be
integrally formed with an implant housed within the
after-loader.
[0078] FIG. 7 shows a plurality of pre-loaded after-loaded devices
202 within a tray 702, according to an embodiment of the present
invention. The tray 702 is shown as including a plurality of
grooves 704, that are configured to frictionally hold fifteen
after-loaders 202. Of course, the tray 702 can be configured to
hold less or more after-loaders 202. Also shown (in dashed line) is
a further radiation shield 706, which provides for some additional
radiation shielding. Such a tray 702 can be part of a kit of the
present invention, and may also have a cover (not shown), both of
which can be placed in a pouch 720. Such a pouch 720, e.g., made of
Tyvek.TM., can keep the contents of the tray 702 sterile until they
are ready for use, and the pouch is opened to reveal its
contents.
[0079] Methods for using the after-loader 202 shall now be
described with reference to FIGS. 8 and 9. Steps that are common to
each method are numbered in the same manner, to avoid replication
of the discussion.
[0080] Referring to FIG. 8, at step 802, the hollow needle is
positioned at the desired location, e.g., with the assistance of a
template. At step 804, the hub of the hollow needle is mated with
the distal end 206 of the after-loader 202, either by way the
enlarged distal portion 220 of the bore 210, the tapered nose 218,
or by using the adaptor 402. At step 806, with the implant
positioned within the after-loader 202, and the after-loader
connected to the hub of the hollow needle, a stylet 302 is inserted
into the opening at the proximal end 208 of the after-loader 202. A
stylet 302 for use with the after-loader 202 can be sufficient in
length to accommodate both the needle 102 and the after-loader 202.
Where that is the case, at step 808, the implant is urged toward
the distal end of the needle until the implant is positioned at the
desired location and depth. Then, the stylet 302 is held in place
while the needle and after-loader are retracted, so that the
implant is deposited at a desired location, as indicated at step
810. Alternatively, a stylet of less than sufficient length to
accommodate both the needle and the after-loader 202 can be
employed. When such a stylet is used, the stylet can be used urge
the implant from the after-loader 202 to the hollow needle, as
indicated at step 806. The stylet can then be removed, and the
after-loader 202 disconnected, as indicated at step 908 in FIG. 9.
A stylet (the same, or a different stylet) can then be inserted
(e.g., reinserted) to urge the implant to the desired location and
depth, at step 910. At step 912, the needle can then be retracted
with the stylet held in position so that the implant is deposited
at the desired location and depth.
[0081] As specified above, each after-loader 202 can be employed
for use with one or more radioactive or other treatment seed, one
or more treatment member (e.g., strand), radioactive rod,
radioactive coil, marker, or some other implant. A strand (also
referred to as a treatment strand) can include a plurality of
radioactive sources spaced apart from one another, e.g. in
accordance with a treatment plan. A strand likely includes a
bioabsorbable material within which treatment sources (e.g.,
radioactive seeds) are encapsulated, and spaced apart from one
another, e.g., in accordance with a treatment plan.
[0082] As specified above, the after-loaders 202 can be pre-loaded
with strands, or other implants so that the pre-loaded
after-loaders can be provided to a physician. Pre-configured
strands or another implant can be loaded into the after-loader 202
off-site and fitted with end plugs at the distal and proximal ends
206 and 208 of the after-loader, and then shipped to the user for a
specific patient. Thus, the proper treatment can be determined as
part of a pre-plan. In such embodiments, the after-loader
preferably would include its shield 250 securely fitted to the
outside surface of the after-loader 202. Such pre-loaded
after-loaders can simplify and expedite the implantation process.
Further, such pre-loaded after-loaders 202 offer benefits to
hospitals or clinics that strive to minify the amount of handling
of the implants performed by staff.
[0083] It is also possible for a physician to load strands into the
after-loaders 202. The physician can do this prior to inserting any
needles into patient tissue. Alternatively, after needles are
inserted into patient tissue, the physician can connect an
after-loader 202 to a needle, and then insert the implant into the
after-loader 202. Thereafter, the physician would urge the implant
from the after-loader 202 into the needle, using a stylet. Other
variations are also possible, as would be understood from the
description herein.
[0084] As will be appreciated, and which can be extrapolated from
the embodiments described, the after-loaders 202 can be longer or
shorter in length as needed. In accordance with specific
embodiments, the after-loader 202 can include an outer diameter
that, at a maximum, does not exceed 5 mm in size to generally match
the pitch of a typical template. However, in other embodiments, the
after-loader 202 can be larger or smaller in diameter.
[0085] The previous description of the preferred embodiments is
provided to enable any person skilled in the art to make or use the
embodiments of the present invention. While the invention has been
particularly shown and described with reference to preferred
embodiments thereof, it will be understood by those skilled in the
art that various changes in form and details may be made therein
without departing from the spirit and scope of the invention.
* * * * *