ENDOSCOPIC LIGATING INSTRUMENT

INSTRUMENT ENDOSCOPIQUE POUR EFFECTUER DES LIGATURES

English Abstract

An endoscopic instrument for ligating multiple lesions within a hollow body organ. A plurality of cords (103) are laid over the tube (101) to extend longitudinally thereon and be folded over the distal end of the tube. A plurality of elastic rings (50) are mounted on the tube (101) in stretched condition and overlaying the cords (103). The segment of each cord (103) between each pair of adjacent rings (50) is in slack condition and of a length which equals or exceeds the distance of the tube's distal end to the furthest ring of the pair. By a trip cord (105) threaded through a working channel (19) of the endoscope and connected to the cords (103), a pull can be exerted thereon to simultaneously retract the cords (103) and dislodge each of the rings in controlled stepped sequence in a procedure wherein only one elastic ring at a time moves over the tube in the process of its dislodgement to ligate a lesion which has been suctioned part way into the tube (101).

French Abstract

Un instrument endoscopique permettant d'effectuer des ligatures sur des lésions multiples dans un organe creux. On place une pluralité de fils (103) sur le tube (101), de sorte qu'ils s'étendent longitudinalement par rapport à ce dernier et se replient sur l'extrémité distale du tube. Plusieurs anneaux élastiques (50) sont montés en position étirée sur le tube (101) et recouvrant les fils (103). Le segment de chaque fil (103) entre chaque paire d'anneaux adjacents (50) est lâche et présente une longueur égale ou supérieure à la distance entre l'extrémité distale du tube et l'anneau le plus éloigné de la paire. Un fil d'actionnement (105) passant dans un canal de travail (19) de l'endoscope et relié aux fils (103) permet d'exercer une traction sur ces derniers de sorte qu'ils se rétractent et que les anneaux soient délogés en séquence échelonnée contrôlée, un seul anneau élastique à la fois se déplaçant le long du tube lors de son délogement pour ligaturer une lésion qui a été aspirée partiellement dans le tube (101).

Claims

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CLAIMS:
1. An endoscopic ligating apparatus, comprising:
a hollow barrel defining a barrel proximal end, a
barrel distal end, a hollow interior and an outer surface;
at least one elastic ligating band stretched
around said barrel outer surface; and
at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material extending through said
hollow interior, folding over said barrel distal end, and
lying between at least a portion of said at least one
ligating band and said outer surface;
wherein pulling said material proximal end in a
proximal direction is operative to pull said material distal
end toward said barrel distal end, thereby pulling said at
least one ligating band off of said barrel distal end.
2. An endoscopic ligating apparatus, comprising:
a hollow barrel defining a barrel proximal end, a
barrel distal end, a hollow interior and an outer surface;
at least one elastic ligating band stretched
around said barrel outer surface; and
at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material extending through said
hollow interior, folding over said barrel distal end, and
lying between at least a portion of said at least one
ligating band and said outer surface;

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wherein pulling said material proximal end in a
proximal direction is operative to pull said at least one
ligating band off of said barrel distal end.
3. An endoscopic ligating apparatus for use with a
flexible endoscope, said endoscope having an endoscope
distal end, said endoscopic ligating apparatus comprising:
a hollow barrel defining a barrel proximal end, a
barrel distal end, a hollow interior having an annular
shoulder formed therein, and an outer surface;
at least one elastic ligating band stretched
around said barrel outer surface; and
at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material extending through said
hollow interior, folding over said barrel distal end, and
lying between at least a portion of said at least one
ligating band and said outer surface;
wherein said hollow interior at said barrel
proximal end is sized to mount over said endoscope distal
end such that said endoscope distal end abuts said annular
shoulder; and
wherein pulling said material proximal end in a
proximal direction is operative to pull said material distal
end toward said barrel distal end, thereby pulling said at
least one ligating band off of said barrel distal end.
4. An endoscopic ligating apparatus, comprising:
a hollow barrel defining a barrel proximal end, a
barrel distal end, a hollow interior having an annular
shoulder formed therein, and an outer surface;

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at least one elastic ligating band stretched
around said barrel outer surface; and
at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material extending through said
hollow interior, folding over said barrel distal end, and
lying between at least a portion of said at least one
ligating band and said outer surface;
wherein said hollow interior at said barrel
proximal end is sized to mount over said endoscope distal
end such that said endoscope distal end abuts said annular
shoulder; and
wherein pulling said material proximal end in a
proximal direction is operative to pull said at least one
ligating band off of said barrel distal end.
5. An endoscopic ligating apparatus, comprising:
a support member defining a support member
proximal end, a support member distal end, a hollow interior
and an outer surface;
at least one elastic ligating band stretched
around said support member outer surface; and
at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material lying between at least
a portion of said at least one ligating band and said outer
surface,
wherein pulling said material proximal end in a
proximal direction is operative to pull said at least one

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ligating band distally off of said support member distal
end.
6. An endoscopic ligating apparatus for use with a
flexible endoscope having an endoscope distal end, said
endoscopic ligating apparatus comprising:
a support member defining a support member
proximal end, a support member distal end, a hollow
interior, and an outer surface;
at least one elastic ligating band stretched
around said support member outer surface; and
at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material lying between at least
a portion of said at least one ligating band and said outer
surface;
wherein said support member proximal end is
adapted to contact a portion of said endoscope distal end;
and
wherein pulling said at least one piece of
flexible material is operative to pull said at least one
ligating band distally off of said support member distal
end.

Description

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ENDOSCOPIC LIGATING INS1'RUMENT
FIELD OF INVENTION
The invention relates to an instruinent for ligating
lesions, and more particularly to an endoscopic instrumeiit
for,ligating mucosal and subinucosal lesions within a hollow
organ of the body, sucli as the alimentary tract.
BACKGROUND OF THE INVENTION
The endoscopic treatmeiit of lesions presently encompasses
a variety of techniques such as electrocauterization, leser
photocoagulation, heat therapy by the application of heat
probes, aricl scierotherapy which involves the iiijection of
iuedicine into a target varix by a needle passed i:lirough tlie
working channel of the endoscope. A further, widely used and
increasingly promising technique involves the ligation of
lesions, wherein mucosal and submucosal tissue is
strangulated by an elastic ligature.
A variety of instrtiments for effecting the ligation of
body tissue by the application of an elastic.ring are well
known in the prior art. Some of these instruments, because
of their rigidity and size are suited only for treatment of
lesioiis that are in the external regions of the body or in
the shallow body cavities. Others are particularly suited

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for ttie ligation of tissue in the abclomitial cavity, such as
for tubal ligation, when the abdominal cavity has been opened
surgically.
U.S. Patent No. 3,760,810 to Van Hoorn discloses an
endoscope-equipped iristrument comprising a device witli two
tubes mounted one insid- the other, with the inner tube
protruding at the front of the outer tube. Means are
included to move the outer tube forwardly relative to the
inrier tube and cause an elastic cord to be disloclged arid
placed about the tissue to be ligated. In U.S. Patent No..
4,257,419, there is disclosed an instrument for ligating
hemorrhoids wherein a suction tube fitted inside a
proctoscope provides means for sucking the hemorrhoid into a
suction cavity where a ligating ring is applied. Both of
these instriiments are rigid devices suited for treating
lesions close to the external regions, and both are equipped
with only a single elastic ring for treating a single lesion.
There are also instruments in the prior art which employ
laparoscope-assisted means for ring ligation such as shown in
U.S. Patent No. 4,257,420 an 4,471,766, wherei.n the
instruments are eacti equipped with a single elastic band and
utilize forceps to position the tissue for ring ligation.
In U.S. Paterit No. 3,870,048, there is disclosed a ring
applicator device having forceps slidably mounted in a
cylinder for grasping the fallopian tube and including means
for displacing an elastic ring to effect a ligation of
tissue. While this device can be eqiii.pped with a plurality
of elastic rings, its rigidity precludes its use with a
flexible endoscope for treating the deeper regions of an
internal orgaii, such as the alimentary tract.
A flexible endoscopic instrument used for ligation
pur2.ioses and disclosed in U.S. Patent No. 4,735,194 comprises
a floxible fiber optic endoscope on the end of which is
secured ari outer tube and aii inner tube reciprocally movable
therein. A trip wire is fastened to the inner tube to

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provide rearward motion to the inner tube to cause an
elastic ririg fitted about the inner tube to slide off and
effect ligation. While this instrument is suitable for
ligating ).esions c7eep within the alimentary tract, it can
only be used to treat but one lesion during a sirigle
irisertion of the instruinent.
In many instances, liuwever, there are a nuniber of lesions
present in the organ being treated, such as the esopliagtis,
stomach or colon. If an endoscopic instrument equipped with
on?y one elastic ring is used, the treatment of multiple
lesioris in the sarne orgaii requires the extraction of the
endoscope after the placing of each elastic ring about a
lesion and reinsertion of tlre endoscope into the organ to
repeat the procedure for placing an elastic ligating ring
about each of the lesions. In addition to being tirne
cons>>ming and an associated concern for blood loss when there
are bleeding lesions, ttiere are other disadvantages
associated with ttie repetitions of this procedure. The
instrument, when withdrawn from the body, is usually covered
witli blood and mucous. Furthermore, each time the instrument
is reinserted into the organ, it becomes necessary to
relocate a lesion to be treated and to orient the instrunient
with respect thereto. In some cases wtiere considerable blood
and mucous are present, the relocating of ttie instrument is a
tedious and difficult task.

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SUMMARY OF TIIE INVENTION
A flexible endoscopic instrument is provided with a
plurality of elastic ligating rings mounted on one tube of a
pair of tubular mernbers which are affixed in coaxial relation
to the insertion end of an endoscope. The rings are adapted
to be dislodged therefrom in sequence at selectively
controlled times for treating niultiple lesions during a
single insertion of the endoscope into a body organ. The
endoscope is equipped wit-h illuinination and viewing means to
io facilitate orientation of the instrument in the body organ,
and longitudinally extending tubular passages.comprising a
channel through whiclr objects rnay be passed and suction
applied for drawing the lesion tissue into the tubular end of
the endoscope to facilitate ligation of a lesion, and a
working channel through which a flexible actuating cable is
inserted. The cable is connected to one of the tubular
members and serves as a means for imparting relative motion
between the pair of tubular members to sequentially dislodge
the elastic rings frorn the endoscope at controlled times.
Eactr of the elastic rings can be dislodged from the endoscope
and placed in ligating relation to a lesion when lesion
tissue is drawn irito the innermost of the tubular mernbers by
a suction force applied ttirough the suction channel and each
of Lhe rings can be applied to a different one of the
multiple lesions in tiie body organ during a single insertion
of the eridoscope.
In one embodiment of the invention, a tubular member is
provided with a lielical groove in its inner wall and with
mearis at one end for fitting the tubular meinber orito the
insertion end of the endoscope. A plurality of elastic
ligaLing rings are mounted in stretched condition about the
periphery of a second tubular mernber which, when inserted
into the first tubular member with a twisting motion, causes

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tlie greater part of each of the elastic riiigs to be placed iri
a different one of the coils of the helical groove. By a
drive gear connection between the flexible cable and the
inner tubular ineinber, rotary niotion of ttie cable is imparted
to the inner tubular member whereby the elastic rings are
adapted to be dislodgec] one at a time to effect ttie ligaL-ion
of nrultiple lesions during a single insertion of the
endoscope.
In a second embodiment, a first rigid tubular meniber is
fitted to the insertion eiid of the endoscope in coaxial
relation thereto. A second tubular member of flexible
material is placed on the rigid tubular member with a first
outer portion tliereof sleeved over the rigid tubular merriber
and a second portion inserted within the first tubular member
by folding over the free end of the rigid tubular member.
The elastic rings are placed in stretched condition about the
outer portion of the flexible tubular member in side-by-side
spaced relation to one another. By direct connection of the
flexible cable to tiie inner second portion of the flexible
tubular inember, the cable can be retracted to pull most of
the outer sleeve portion over the free end of the rigid tube
arid into the interior of the rigid tubular member thereby
causing the elastic rings to be dislodged from the endoscope
one at a time as they pass over the end of the rigid tubular
member at times controlled by the ret-ractiozi of tlre flexible
cable.
In a third embodiment, a rigid tubular member is fitted
to the insertion end of the endoscope and a plurality of
cords connected together at the saine point inside the tube,
are each folded over its distal end with the free end portion
thereof extending in the longitudinal direction of the tube
arrd aiigularly spaced relative to one another witli respect to
tlie axis of tlie tube. A plurality of elastic riligs are
placed in stretched conditiori about the tube at
longiLudinally spaced locations thereori and also over the

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cords which lay over the tube. Each cord is provided with
knots at predetermined spaced locations thereon against each
of which an elastic ring is placed. By means of a trip wire
or trip line threaded through a working channel of the
endoscope and connecting to the cords at this mutual
connecting point, the cords can be simultaneously retracted
to pull the rings over the distal end of the tube in
controlled sequence. By also providing a slack length of
the cord between each pair of adjacent elastic rings, which
slack length equals or exceeds the distance of the tube's
distal end to the furthermost ring of the pair a small
pulling force is required to dislodge a ring from the tube.
Thus, in a broad aspect the invention provides a
flexible endoscopic instrument for ligating a multiplicity
of lesions within a hollow body organ, such as the
alimentary tract, said instrument comprising: (a) a flexible
fiber optic endoscope having a forward insertion end and a
rearward end, said endoscope including means for
illumination and viewing through said endoscope, means for
providing a suction force at said insertion end, and a
working channel; (b) a tubular member having a forward
distal end, a rearward end and a longitudinal axis, said
rearward end having means for providing attachment to the
insertion end of the endoscope; (c) a plurality of string-
like cords of flexible substantially inelastic material,
each said cord being folded over the distal end of the
tubular member with a first portion of each said cord
overlaying a part of the exterior of said tubular member and
a second portion thereof being disposed internally of said
tubular member, said cords being oriented in angular spacing
about the longitudinal axis of said tubular member; (d) a
plurality of elastic ligating rings removably mounted in
stretched condition on said tubular member in coaxial

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relation thereto and in overlying relation to said cords,
said rings being spaced from one another in the longitudinal
direction of the tubular member at successively greater
different distances from the distal end of the tubular
member; and (e) means for imparting relative sliding motion
between said cords and said tubular member to dislodge each
of the elastic rings in controlled sequence during a single
insertion of the endoscope into the body organ whereby each
of the elastic rings can be dislodged from the endoscope and
placed in ligating relation to a lesion when lesion tissue
is drawn into the tubular member by said suction means with
each ring being applied to a different one of multiple
lesions present in the body organ, said means comprising a
flexible line element threaded through the working channel
of the endoscope and connecting at one end to said cords
disposed within said tubular member and exiting the
endoscope at the rearward end thereof whereby a pulling
force may be exerted on the other end of the line element to
cause sliding movement of the cords over said tubular
member, each said cord being arranged in slack condition
between each pair of adjacent elastic rings.
In another aspect the invention provides a
flexible endoscopic instrument for ligating a multiplicity
of lesions within a hollow body organ, such as the
alimentary tract, said instrument comprising: (a) a flexible
fiber optic endoscope having a forward insertion end and a
rearward end, said endoscope including means for
illumination and viewing through said endoscope, means for
providing a suction force at said insertion end, and a
working channel; (b) a tubular member having a forward
distal end, a rearward end and a longitudinal axis, said
rearward end having means for providing attachment to the
insertion end of the endoscope; (c) a plurality of string-

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like cords of flexible substantially inelastic material,
each said cord being folded over the distal end of the
tubular member with a first portion of each said cord
overlaying a part of the exterior of said tubular member and
a second portion thereof being disposed internally of said
tubular member, said cords being oriented in angular spacing
about the longitudinal axis of said tubular member; (d) a
plurality of elastic ligating rings removably mounted in
stretched condition on said tubular member in coaxial
relation thereto and in overlying relation to said cords,
said rings being spaced from one another in the longitudinal
direction of the tubular member and between at least one
pair of adjacent elastic rings each of said cords having a
slack segment of cord of a length which is at least equal to
the distance between the distal end of the tubular member
and the ring of said pair which is furthest from said distal
end; and (e) means for imparting relative sliding motion
between said cords and said tubular member to dislodge each
of the elastic rings in controlled sequence during a single
insertion of the endoscope into the body organ whereby each
of the elastic rings can be dislodged from the endoscope and
placed in ligating relation to a lesion when lesion tissue
is drawn into the tubular member by said suction means with
each ring being applied to a different one of multiple
lesions present in the body organ, said means comprising a
flexible line element threaded through the working channel
of the endoscope and connecting at one end to said cords
disposed within said tubular member and exiting the
endoscope at the rearward end thereof whereby a pulling
force may be exerted on the other end of the line element to
cause sliding movement of the cords over said tubular
member, each said cord being arranged in slack condition
between each pair of adjacent elastic rings.

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In another aspect the invention provides a
flexible endoscopic instrument for multiple ligation, said
instrument comprising: (a) a flexible endoscope having a
forward insertion portion, said endoscope including means
for illumination and viewing through said endoscope, means
for providing a suction force at said insertion portion, and
a working channel; (b) a hollow support member having a
forward distal end and a rearward portion, said rearward
portion being connectable to the insertion portion of the
endoscope; (c) at least two string-like cords of flexible
substantially inelastic material, each of said cords having
a first portion overlaying a part of the exterior of said
support member and a second portion disposed internally of
said support member; and (d) a plurality of elastic ligating
rings removably mounted in stretched condition on said
support member and each of said rings being in overlying
contacting relation to each of said cords, said rings being
spaced from one another along said support member at
successively greater different distances from said distal
end of said support member; wherein a pulling force may be
exerted on each of said cords to cause movement of each of
said cords relative to said support member to dislodge one
or more of said rings in controlled sequence from said
support member, each of said cords being arranged in slack
condition between each pair of adjacent elastic rings.
In another aspect the invention provides use of a
ligation apparatus for ligating tissue, said ligation
apparatus including: a hollow support member having a
forward distal end and a rearward portion; at least two
string-like cords of flexible substantially inelastic
material, each of said cords having a first portion
overlaying a part of the exterior of said support member and
a second portion disposed internally of said support member;

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and a plurality of elastic ligating rings removably mounted
in stretched condition on said support member and each of
said rings being in overlying contacting relation to each of
said cords, each of said cords being arranged in slack
condition between each pair of adjacent elastic rings,
wherein: said rearward portion of said support member is
capable of connection to a forward insertion end of an
endoscope; said forward end of said support member is
capable of insertion into a body organ and placement
adjacent tissue to be ligated; said ligation apparatus is
capable of drawing tissue within said support member; and
said ligation apparatus is capable of dislodging one of said
rings from said support member to ligate tissue drawn within
said support member upon exertion of a pulling force on each
of said cords.
In another aspect the invention provides a
flexible endoscopic instrument for multiple ligation, said
instrument comprising: (a) a flexible endoscope having a
forward insertion portion, said endoscope including means
for illumination and viewing through said endoscope, means
for providing a suction force at said insertion portion, and
a working channel; (b) a hollow support member having a
forward distal end and a rearward portion, said rearward
portion being connectable to the insertion portion of the
endoscope; (c) at least two string-like cords of flexible
substantially inelastic material, each of said cords having
a first portion overlaying a part of the exterior of said
support member and a second portion disposed internally of
said support member; and (d) a plurality of elastic ligating
rings removably mounted in stretched condition on said
support member and each of said rings being in contacting
relation to each of said cords, said rings being spaced from
one another along said support member at successively

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greater different distances from said distal end of said
support member; wherein a pulling force may be exerted on
each of said cords to cause movement of each of said cords
relative to said support member to dislodge one or more of
said rings in controlled sequence from said support member,
each of said cords being arranged in slack condition between
each pair of adjacent elastic rings.
In another aspect the invention provides a
flexible endoscopic instrument for multiple ligation, said
instrument comprising: (a) a flexible endoscope having a
forward insertion portion, said endoscope including means
for illumination and viewing through said endoscope, means
for providing a suction force at said insertion portion, and
a working channel; (b) a hollow support member having a
forward distal end and a rearward portion, said rearward
portion being connectable to the insertion portion of the
endoscope; (c) at least one string-like cord of flexible
substantially inelastic material, each said cord having a
first portion overlaying a part of the exterior of said
support member and a second portion disposed internally of
said support member; and (d) a plurality of elastic ligating
rings removably mounted in stretched condition on said
support member and each of said rings being in overlying
contacting relation to each said cord, said rings being
spaced from one another along said support member at
successively greater different distances from said distal
end of said support member; wherein a pulling force may be
exerted on each said cord to cause movement of each said
cord relative to said support member to dislodge one or more
of said rings in controlled sequence from said support
member, each said cord being arranged in slack condition
between each pair of adjacent elastic rings.

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In another aspect the invention provides use of a
ligation apparatus for ligating tissue, said ligation
apparatus including: a hollow support member having a
forward distal end and a rearward portion; at least one
string-like cord of flexible substantially inelastic
material, each said cord having a first portion overlaying a
part of the exterior of said support member and a second
portion disposed internally of said support member; and a
plurality of elastic ligating rings removably mounted in
stretched condition on said support member and each of said
rings being in overlying contacting relation to each said
cord, each said cord being arranged in slack condition
between each pair of adjacent elastic rings, wherein: said
rearward portion of said support member is capable of
connection to a forward insertion end of an endoscope; said
forward end of said support member is capable of insertion
into a body organ and placement adjacent tissue to be
ligated; said ligation apparatus is capable of drawing
tissue adjacent to said forward end, within said support
member; and said ligation apparatus is capable of dislodging
one of said rings from said support member to ligate tissue
drawn within said support member upon exertion of a pulling
force on each said cord.
In another aspect the invention provides a
flexible endoscopic instrument for multiple ligation, said
instrument comprising: (a) a flexible endoscope having a
forward insertion portion, said endoscope including means
for illumination and viewing through said endoscope, means
for providing a suction force at said insertion portion, and
a working channel; (b) a hollow support member having a
forward distal end and a rearward portion, said rearward
portion being connectable to the insertion portion of the
endoscope; (c) at least one string-like cord of flexible

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substantially inelastic material, each said cord having a
first portion overlaying a part of the exterior of said
support member and a second portion disposed internally of
said support member; and (d) a plurality of elastic ligating
rings removably mounted in stretched condition on said
support member and each of said rings being in contacting
relation to each said cord, said rings being spaced from one
another along said support member at successively greater
different distances from said distal end of said support
member; wherein a pulling force may be exerted on each said
cord to cause movement of each said cord relative to said
support member to dislodge one or more of said rings in
controlled sequence from said support member, each said cord
being arranged in slack condition between each pair of
adjacent elastic rings.
In another aspect the invention provides an
endoscopic ligating apparatus, comprising: a hollow barrel
defining a barrel proximal end, a barrel distal end, a
hollow interior and an outer surface; at least one elastic
ligating band stretched around said barrel outer surface;
and at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material extending through said
hollow interi'or, folding over said barrel distal end, and
lying between at least a portion of said at least one
ligating band and said outer surface; wherein pulling said
material proximal end in a proximal direction is operative
to pull said material distal end toward said barrel distal
end, thereby pulling said at least one ligating band off of
said barrel distal end.
In another aspect the invention provides an
endoscopic ligating apparatus, comprising: a hollow barrel
defining a barrel proximal end, a barrel distal end, a

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hollow interior and an outer surface; at least one elastic
ligating band stretched around said barrel outer surface;
and at least one piece of flexible material having a
material proximal end and a material distal end, said at
least one piece of flexible material extending through said
hollow interior, folding over said barrel distal end, and
lying between at least a portion of said at least one
ligating band and said outer surface; wherein pulling said
material proximal end in a proximal direction is operative
to pull said at least one ligating band off of said barrel
distal end.
In another aspect the invention provides an
endoscopic ligating apparatus for use with a flexible
endoscope, said endoscope having an endoscope distal end,
said endoscopic ligating apparatus comprising: a hollow
barrel defining a barrel proximal end, a barrel distal end,
a hollow interior having an annular shoulder formed therein,
and an outer surface; at least one elastic ligating band
stretched around said barrel outer surface; and at least one
piece of flexible material having a material proximal end
and a material distal end, said at least one piece of
flexible material extending through said hollow interior,
folding over said barrel distal end, and lying between at
least a portion of said at least one ligating band and said
outer surface; wherein said hollow interior at said barrel
proximal end is sized to mount over said endoscope distal
end such that said endoscope distal end abuts said annular
shoulder; and wherein pulling said material proximal end in
a proximal direction is operative to pull said material
distal end toward said barrel distal end, thereby pulling
said at least one ligating band off of said barrel distal
end.

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In another aspect the invention provides an
endoscopic ligating apparatus, comprising: a hollow barrel
defining a barrel proximal end, a barrel distal end, a
hollow interior having an annular shoulder formed therein,
and an outer surface; at least one elastic ligating band
stretched around said barrel outer surface; and at least one
piece of flexible material having a material proximal end
and a material distal end, said at least one piece of
flexible material extending through said hollow interior,
folding over said barrel distal end, and lying between at
least a portion of said at least one ligating band and said
outer surface; wherein said hollow interior at said barrel
proximal end is sized to mount over said endoscope distal
end such that said endoscope distal end abuts said annular
shoulder; and wherein pulling said material proximal end in
a proximal direction is operative to pull said at least one
ligating band off of said barrel distal end.
In another aspect the invention provides an
endoscopic ligating apparatus, comprising: a support member
defining a support member proximal end, a support member
distal end, a hollow interior and an outer surface; at least
one elastic ligating band stretched around said support
member outer surface; and at least one piece of flexible
material having a material proximal end and a material
distal end, said at least one piece of flexible material
lying between at least a portion of said at least one
ligating band and said outer surface, wherein pulling said
material proximal end in a proximal direction is operative
to pull said at least one ligating band distally off of said
support member distal end.
In another aspect the invention provides an
endoscopic ligating apparatus for use with a flexible
endoscope having an endoscope distal end, said endoscopic

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ligating apparatus comprising: a support member defining a
support member proximal end, a support member distal end, a
hollow interior, and an outer surface; at least one elastic
ligating band stretched around said support member outer
surface; and at least one piece of flexible material having
a material proximal end and a material distal end, said at
least one piece of flexible material lying between at least
a portion of said at least one ligating band and said outer
surface; wherein said support member proximal end is adapted
to contact a portion of said endoscope distal end; and
wherein pulling said at least one piece of flexible material
is operative to pull said at least one ligating band
distally off of said support member distal end.

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BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal view, partly in section of an
endoscopic ligating instrument representing a preferred
embodiment of the invention;
FIG. 2 is a frontal plan view of the insertion end of the
endoscopic ligating instrument of FIG. 1;
FIG. 3 is a section view through the end portion of the
instrtrment as taken along the section line 3-3 in FIG. 2;
FIG. 4 is a fragmentary view in cross-section showing
details of the end portion of the flexible actuating cable at
its connection with a planetary gear in a tubular niember in
an assembly of tubular members affixed to the insertion end
of the endoscope;
FIG. 5 is a section view throuyh the iiisertion end of the
endoscope as taken along the section line 5-5 in FIG. 3;
FIG. 6 is an exploded view of a tubular assembly wlrich is
affixed to the inserLion end of the endoscope;
FIG. 7 is a fragmentary view, partly in section, showing
the insertion end of the instrument of the invention applied
to a lesion witti lesion tissue drawn by suction into arr inner
tubular nrenrber on the end of the instrument;
FIG. 8 is a view similar to FIG. 7, but showing an
elastic ligating ring applied about a lesion after its
dislodgement front lie end of the endoscopic instrument of the
invention;
FIG. 9 shows a lesion witfi an elastic ligating ring
applied in strangulatirrg relaLionship hereto;
FIG. 10 is a block plan view showing an endoscopic
instrument as shown in FIG. 1 which is provided with a
step-niotor for selecLively and automatically controlling the
rotation of the flexible cable;
FIG. 11 is a fragmentary view in longitudinal
cross-section of a modified form of tubular assembly wlricli is
connectable to the insertion end of the endoscope of the

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invention;
FIG. 12 is a sectional view as taken along the sectiori
line 12-12 in FIG. 11;
FIG. 13 is an enlarged fragmentary view of the tubular
assembly of FIG. 11 which shows the nature and direction of
the relative movemerit wliich is imposed between the paired
tubular meniber of the assembly for effecting the discharge of
an elastic ligating ring;
FIG. 14 is a view siinilar to FIG. 13 but sliowing a
modified form of ribbing which is provided on the exterior of
a LexLile mernber of the Luvular assenibly of FIG. 11; arrd
FIG. 15 is a plan view of an embodiment of the inverlL-ior-
as illustrated in FIGS. 11 - 14.
FIG. 16 is a perspective fragmentary view of a furtlier
embodiment of the invention showing the insertiori end of an
endoscope witti elastic rings displaceably mounted on a rigid
tube affixed tlieret-o;
FIG. 17 is a frorit view of the apparatus attaclied to the
insertion end of the endoscope of FIG. 16;
FIG. 18 is a longitudinal sectional view of the endoscope
apparatus as taken along the sectzori line 18-18 in FIG. 17
showing the arrarigement of elastic rings on the rigid tube
connected to the end of the endoscope;
FIG. 19 is an erilarged fragmentary view showing the
distal end of the tubular meinber fitted to the end of the
endoscope in FIG. 16; and
FIG. 20 is a longiLuclinal sectiorial view similar to FIG.
18 but showing a suctioned lesion ligated by an elastic ring
which has been dislodged from the tube.

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DETAILED DESCRIPTION OF THE INVENTION
Referring more particularly to the drawings, there is
shown in FIG. 1 a flexible endoscopic instrument 10 of a
lengtli which perniits access to the deeper regions of a hollow
body organ, such as the alimentary tract. The instrument 10
comprises a conventional endoscope with an operating controls
section 11 of rigid coristructioii and a flexible sectiori 12
wliich extends therefrom and is a length sufficient to reach
the deeper regions of the alimentary tract. The distal end
of the flexible sectiozr 12 is the iiisertion end 13 of the
endoscope and the viewing end 14 of the endoscope is at the
erid of the rigid operating controls section 11 remote from
the end tlsereof which connects to the flexible section 12.
Ttie endoscope is provided with passages 16-21 which
extend longitudinally therein from its insertion end 13 to
exit ports near the viewing end of ttie endoscope. The
passages comprise an illumiriation channel 16 through which is
inserted a fiber optic cable for the transmission of light
from a light source, a viewing channel 17 whicli is also
provided with a fiber optic cable for viewing purposes, and a
channel through which objects may be passed or suction
applied 18. The illuniiriation channel and suction channel
exit laterally througli a lateral extension 22 of tiie side
wall of the endoscope at a location on the operating controls
section 11 near the viewing end 14. At their exit location,
the fiber optic cable f-rom channel 16 and the channel 18 are
connectable through an.umbilical cable 23 to a control device
(riot shown) wliicli is adaptable for supplying illumination to
ttie transinission optic cable and for connecting the channel
18 to an appropriate means for applying a suction
therelhrougli. The fiber optic viewing channel 17 extends to
the viewing ericl 14 of the eric]oscope which may lie p.iovidecl
witti a viewing lens aiid an adapter for mounting a caniera
tliereon, if desired.

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The endoscope is also provided with a working channel 19
which extends througli the endoscope from its inserl=ion end 11
to an exit in the lateral extension 22. The working cliannel
19 includes a branch 19a which extends i:lirough an angularly
exteiiding protuberance 24 to a second exit near the viewing
end of the endoscope.
Additional channels 20 ancl 21, shown in FIG. 2, may be
utilized for delivering pressurized air or a jet stream of
water for cleanirig the lens.
In the ecubodiment of the iriverition sliown in FIGS. 1-6,
the insertion end of the ericioscope is fitted with an assembly
of coaxially arranged tubes 25, 26, the outer tube 26 of
wLich is secured in coaxial relation thereto preferably by a
tubular adapter 27 which provides a friction fit as shown in
FIG. 3 although other fastening means such as a threaded
connection niiglit be suitably employed. The tube 26 is
preferably of transparent plastic material for enhancing the
illumination and field of vision from the insertion end of
the endoscope, altliougli otlier inert material miglit also be
suitable includirig stainless steel. The tube 26 is provided
at its attaching end with an external frusto-conical bevel
surface 28 to facilitate the placement of the tubular adapter
27 thereover. The adapter 27 is preferably of a flexible
material such as plastic and is provided with an internal
diameter which allows it to be sleeved tightly over the tube
26. For furtlier en}rancirig the connecLion, the adapter 27 is
provided witli an internal annular flange 31 which is adapted
to seat in an accommodating annular groove 32 from externally
about the surface of the tube 26, tliereby locking the adapter
27 to the tube 26.
At its otlier end, the inner wall of the adapter 27 is
fornied with a succession of outwardly diverging
frusto-conical grooved surfaces 34 wliich provide teeth-like
edges for enhancing its grip on the endoscope when sleeved
over the end thereof. In addition, it is provided with an

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internal annular latchiiig flange 36 which is adapted to seat
in a latcliing groove 37 formed about the exterior of the
endoscope.
The inner wall of outer tube 26 is formed with a lielical
groove 40 which extends from its distal end for the greater
part of its lengt-li. Near its attacliing end, the inner wall
of outer tube 26 is formed with an internal annular flange 41.
The inner tubular member 25 has a forward end 42 and a
rearward erid 43 and comprises a first elongate section 44 and
an adjoining shorter section 45 of circular cylinder
configuration and larger radial dimensions. Tl-e tubular
u-ember 25 llas an external annular shoulder 46 formea at the
jiinction of the elongate tubular section 44 with the larger
diameter section 45. The tubular member 25 is also provided
an i,iternal annular radial slioulder 47, wliich is forined at
the juriction of the bore of section 45 with the smaller bore
of the elongate section 44.
Ttie elongate section 44 lias a radial cross section in the
configuration of a segntented circle and an external
cylindrical surface characterized by an elongate planar
surface section 48 which exteiids froin the forward end 42 of
ttie tubular member 25 to the radial shoulder 46.
The inner tubular member 25 serves as a carrier for a
plurality of elastic ligating rings 50 wliich are placed in
stretclied coridition about the elongate section 44 and mounted
thereon in side-by-side relation to one another and in
sleeved relation to the section 44. Z'he elastic rings 50 are
typically of rubber rnaterial or an inert non-toxic plastic
composition.
The tubular mernber 25 is also provided with a circular
plarietary gear 52 wliicli is seated in the bore of the circular
section 45 in the coaxial reaction therewith. The gear 52
may be fabricated as an integral part of the tubular meniber
25 or it could be separately formed and bonded to the radial
shoulder 47 and the inner cylindrical wall of circular

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section 45 by an appropriate adhesive although other
fastening means could also be used. An opening 49 is also
provided in the radial shoulcler 47 to insure full
communication of the interiors of the tubular members 25 and
26 with the suction channel 18.
When completely assembled as shown in FIG. 3, the gear
teeth of planetary gear 52 are in meshing engagement with a
drive gear 53 which is mounted by a connecting adapter 54 on
the enc] of a flexible steel cable 55, preferably a single
wire, which is inserted through the working clianriel 19 of the
eridoscope. The cable 55 extends through the working channel
section 19a where it is fitted with a rotary control mearis
sucli as knob 56 for manually effecting axial rotation of the
cable 55.
The adapter 54 cotnprises a shaf t 57 enlarged at one erid
which is provided with a socket 58 characterized by a socket
cavity of rectangular transverse cross-section which receives
the squared erid of the cable 55. At its otlier end, the shaf t
57 is journaled for rotation on a transverse support 60
fitted internally of tube 25. Ttie shaft 57 is also fitted
with a drive gear 53 which is fixed on the shaft 57 in
coaxial relation thereL-o by a press fit or any suitable
bonding means. Also sleeved about the shaft 57 is a plastic
spacer 59 which is in abutting engagement with the drive gear
53 and one end of the socket 58.
Also sliown in FIG. 3, a retaining riilg 61 is also fitted
irrto the end of the inner tubular nieiiiber 25 in coaxial
relation therewith and in abutting engagement with both ttie
rearward end of the tubular member 25 and the planetary gear
52. The retaining ring 61 is provided in its outer surface
with a circumferential groove 62 whicli receives the annular
flange 41 of the tubular member 25 and latches the retaining
iing 61 iri position.
In assembly of the instrurnent 10 of tlie elastic ligatiiig
rings 50 must be placed onto tlie inner tubular mernber 25

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before it is inserted in the outer tubular member 26. This
is also done before the i.ubular members 25, 26 are fitted
onto the endoscope. The elastic ligating rings 50, when iri
the relaxed state are of a diameter less than that of the
inserLion end of the endoscope, wliicli for representative
endoscopes, is in the range of approximately 9mm to 13mm.
The rings 50 are placed in stretched condition onto the
elongate section 44 of the tubular member 25 in side-by-side
relation to one another and in sleeved relation to the
section 44. The tubular member 25 is then inserted with an
axially twisting motion tlirough the attaching end of the
otiter tubular meniber 26 whereby each elastic ring, except for
the portion thereof which rests atop the planar surface of
the inner tubular member 25, is placed in a coil of the
helical groove 40 in spaced relation to the adjacent elastic
ring in the next adjacent coil of the helical groove.
The tubular assembly, coniprising tubular member 25 and 26
witli tubular adapter 27 secured to the member 26, is then
sleeved onto the insertion end of the endoscope such that the
planetary gear 52 and drive gear 53 are in meshed driving
engagement witli orie another and the attaching end of the
tubular member 26 abuts the insertion end of the endoscope.
When treating a paL-ient, the endoscopic instrument of the
inverltion is first iiiserted into the affected orgarr, such as
the alimentary tract, to place the insertion end of the
endoscope in the vicinity of lesions in the alimentary
tract. In some iilstances, liowever, it rnay be preferred that
insertioii of the instrurnent be preceded by the insertion of
an encloscopic overtube (not shown) into the alimentary tract
atid the instrumerit then be inserted through the overtube. In
either case, the instrument is then oriented for sighting of
a target lesion, such as lesion 77 shown in FIG. 7, and the
instrument advanced tiiider the control of a liuman operator
until the distal end of the tubular rnember 25 contacts the
lesion area and is placed in surrounding relation to the
target lesion.

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A suction force is Llien applied through the suction
chazinel 18 to conrpletely draw the lesion tissue into the
inner tubular meinber 25 as shown in FIG. 7. The operator
then manually initiaLes axial rotation of the cable 55 and
the inner tubular member 25 in the spirally forward direction
of the helical groove 40 whereby the elastic rings 50 are
driven along Llie surface of the tubular merrrber 25 by the
walls of the helical groove 40 until one of the elastic ririgs
is dislodged from ttie instrurnent and placed in ligating
relation about Llie base of Llie target lesion as shown in FIG.
8. Tlte end of the instrunient 10 is then withdrawn from
around the lesion tissue, as shown in FIG. 9.
It is to be appreciated that by continuing the axial
rotation of the tubular rrteniber 25, more of the elastic rings
can be dislodged from the instrurnent. Accordingly, the
enc7oscopic iristrument of the invention permits the successive
ligation of rnult=iple lesions during a single insertion of the
instrurnent. With patienL-s who are not bleeding, the ligation
treatrnent is started at the niost distal point in the
aliiiientary tract and then continued proxirnally so that
elastic bands wliich are placed about the lesioii tissue are
not disturbed by movement of the instrument. The instrument
ttierefore facilitates the treatment of multiple lesions and
alleviates the need for repeated removal and reinsertion of
the instrument and reloading of an elastic ring for treating
each lesion.
In sorne instances, particularly where vision is oLscured,
the instrument operator may liave diffictilty in ascertaining
the precise amouiit of rotation of the flexible cable 55 tliat
is iiecessary for dislodging one and only one elastic ring 50
when ligating a single target lesioii. In this respect, a
rnodified form of Llie inveriLion, which enables the axial
rotation of the cable 55 in steps of precise amounts, is
represented by ttie endoscopic instrurnent 7U as shown in
scliematic form in FIG. 10. The instrument 70 is ideiitical in

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all respects to the irrstrumenl 10 except for the means of
iinparting axial rotation to the flexible cable 55 and
identical components are identically numbered. in lieu of a
knob 56 which enables the manual rotation of the cable 55,
the instrument 70 is provided with automatic means
represented by a stepping motor 72 and a controller 74 for
rotation of the cable 55 in precisely controlled amounts.
The controller 74 and inotor 72 are connected to receive power
from ari electrical power source 76. A foot pedal triyger
switclr 75 is used by tlre operator to energize the steppiny
motor 72 for a precise time interval during which time the
flexible cable 55 is axially rotated by an amourit which moves
the elastic rings a precise distance along the tubular rnember
25 such that the most distal elastic ring 50 is forced off
the end of the tubular niember 25 and the remainirig ring 50 is
forced off ttie end of the tubular niember 25 and the remaining
rings 50 are retained thereon. In effect, the precise time
interval of motor operation moves the elastic rings a
distance wtiich corresponds to the distance between adjacent
coils of the helical groove 40.
It is to be appreciated therefore that the endoscopic
instrument 70 provides tlre operator with means for precisely
controlling wtieri an elastic ring 50 is dislodged from the
instrument and for insuring that oiily one elastic ring is
dislodge when ligating a target lesion. It is therefore
possible for the operator to dislodged additiorral elastic
rings in sequence and at tiines controlled by the operator so
tlrat multiple lesions can be ligated during a single
insertion of the instrument.
A further embodiment of the invention represented by the
eridoscopic instrument 80 is disclosed in FIGS. 11-15. The
endoscopic instrument 80 differs from t.tie instruments 10 and
70 in the nature and operation of the tubular assembly which
is affixed to the irisertion end of ttie endoscope, but is
otlierwise iderrtical thereto. As si-iown in FIG. 11, a rigid

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tube 81 is fixed in coaxial relation to the insertion encl of
the endoscope, preferably by a sleeve adapter 82. A tubular
textile rneniber 83 of an inelastic material, such as the
conunercial product Kevlar or other inelastic flexible
material, is mounted onto the rigid tube 81 such that the
member 83 is folded over the distal end of the tube 81 with a
first portion 83a thereof being sleeved over the tube 81 and
a second portion 83b thereof disposed internally of the tube
81 and substantially coaxial thereto.
As sliown in FIG. 11, a plurality of elasl:ic ligating
rings 50a are placed in stretched condition in encircling
relation about the portion 83a of the tubular mernber 83. The
textile material of portion 83a is provided with an external
surface 1-iaving a plurality of annular ridges 84 in the
encirclirrg r.elation thereto and preferably arranged in pairs
wiricly define a plurality of urriforrnly spaced annular recesses
or grooves 85, each of whiclr is adapted to receive an elastic
ring 50a ttierein. The elastic rings 50a are therefore
maintained in uniform side-by-side spacing on the tubular
portion 83a.
The end of the second portion 83b of the textile tubular
member 83 is fitted with a rigid aiiiiular ring clamping
assembly 86 to which the textile fabric of the tubular meniber
83 is attached. The clamping assernbly 86 comprises an outer
retaining ring 86a and an inner clamping ring 86b whicli is of
a smaller external diarneter tlrarr the internal diarneter of the
outer ring 86a and is irisertable therein from the distal end
of the t-ube 81 to clamp tlie portion 83b of the textile
tubular member 83 tlrerebetween. Preferably, the inner wall
of the outer ring 86a is forrned with an annular coaxial
groove 87 and the outer wall of the inner ring 86b is formed
with an annular ridge 88 of conforrrring configuration and
location such as to serve in retaining the textile mernber 83
therebetween. The outer ring 86a is also provided with at
least tliree cenL-ering protuberances 90 wliich are in uniforrn

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angular spacing and serve to maintain the ring 86a in coaxial
relation to the tube 81 and in a tight friction fit therein.
As best seen in FIG. 11, the adapter 82 is sleeved over
an annular bevel surface 89 oiz the attaching end of the tube
81 and is provided with an internal annular flange 91 which
latches in an anriular groove 92 formed about the external
surface of the rigid tube 81. At its other end, the adapter
is designed for a press fit connection with the insertion end
oi ttie endoscope as provided for the adapter 27 in the
embodimerit of FIG. 1 or could be provided with threads, if
desired.
A flexible cable 55a, similar to the cable 55 sliown in
the embodiment of FIG. 1, and similarly tlireaded througli the
working channel of the endoscope is attached to an internal
flange 93 on the inner wall of the clainping ring 86b. As
best seeri iri FIGS. 11 and 12, one end of the cable 55a is
placed in an axial blind bore formed inwardly from one end of
a sleeve inernber 94 wlriclr is swayed in engagement tlierewith.
The sleeve member 94 which is externally tllreaded at its
other end, is inserted through an opening in the flange 93
and secured by a nut 95 on its threaded end. It is thus to
be seen that by a pull on the cable 55a to the right as sliown
in FIG. 11, the portion 83b of textile tubular nieniber 83
which is ir_terior of the rigid tube 81 is increased and the
portion 83a whicli is exterior of the tube 81 is decreased.
The relative movernent of the flexible tube 83 with
respect to the rigid tube 81 is illustrated by arrows in FIG
13 whicli show the textile tubular meiuber 83 sliding over the
distal errd of the tube 81. As this movenient increases, the
most distal of the elastic ligating rings 50a passes over the
distal etid of the tube 81 and is discharged ttierefrarn. When
the assen-bly of tubes 81, 83 are placed in surrounding
relation to a target lesion, and lesion tissue is drawn into
tlre tube 83 by suction iri a inanner as previously described,
it is to be appreciated that ligation of a lesion as shown in

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FIG. 9 can be readily acliieved.
It is irnportanL that only a single ligat-irig ring 50a be
discharged frorn the instrument 80 for treating each lesion
and the movemerit of the cable 50a must be determined
accordingly. AFter treating one lesion, the instrument can
be reoriented in surroiinding relation to another lesion and
the proceclure repeated. Accordingly, multiple lesions can be
ligated during a single insertion of the instrument. For
most applications, the instrument shotild be provided with at
least six elastic rings 50a.
In FIG. 15, the cable 55a is shown attached to a reel 96
whereby an indexed rotatioii thereof is designed to move the
cable 55a a predeterniined distance to cause the discharge of
only a single ligating ring 50a. Obviously, the inovemerit --
could be coritrolled manually or other techniques eiiiployed for
controlling a precise axial movement of the cable 55a.
A variation in the arrangement of ridges 84 on the
external surface of the textile tubular member 83 is shown in
FIG. 14. In this modified form of the member 83, only a
single ridge 84 is used for aligning the elastic rizigs 50a in
uniform spacing ori the member 83. The rings 50a are
installed wliereby each is in abutting engagement with the
side of a ridge 84 which faces toward the distal end of the
tubular assembly so as to preveiit their being moved or
disturbed as tlie instriimerit is inserted into a body organ.
It is to be noled tliat iii tlie einbodiment of ttie invention
disclosed in FIGS. 11-15, the force required to pull the
sleeve inember 83 over the distal end of the tube 81 iilcreases
proportionately witli the number of elastic rings, such that a
strong aricl sturdy construction must be used for the parts
mounted on ttre insertion end of the endoscope and the
coinponent parl-s for imparting sliding movement beL-weer- tlie
sleeve 83 and the tube 81 and for a precise ainouiit of slidlSlg
to ensure that orily orie ring is dislodged at a time. The
force to dislodge the first riiig, which must be strong enough

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i ~.
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-
to pull the sleeve and all the elastic rings towards the
distal end of the tube, is considerably greater than the
force required to dislodge the last remaining elastic ring
from the tube.
A third embodimerit of the invention represerited by the
endoscopic instrument 100 disclosed iri FIGS. 16-19 requires a
pulliilg force to dislodge an elastic ring which is comparable
to that required for dislodging the last ring of the sleeve
version disclosed in FIGS. 11-15. As best seen in FIG. 16, a
transparent rigid tube 101 is fitted to the insertion end of
the endoscope 100 by an adapter section 102 whicli provides a
friction fit witli the iiisertiozi end of the endoscope. The
endoscope 100 is provided with a plurality of flexible and
substantially in elastic cords 103, each of which is folded over
the distal end of tiie tube 101 and includes a first portion
which is laid over the exterior surface of the tube and a
secorid portion wliich is disposed iiiternally of the tube. The
ends of the cords 103 iiiside the tube are fastened to oiie end
of a flexible line 105 as by tying thereto or the use of an
adapter connector 106. From its connection with cords 103,
the flexible line 105 is threaded through the working channel
19 of the endoscope and exits near the rearward end of the
endoscope sucli that L-he exiting end portion of the line 105
may be fitted witti a handle.
As best seen in FIG. 17, the cords 103 are disposed in
preferably uniforin angular spacing about the longitudinal
axis 107 of the tube 101. A plurality of elastic ligating
rings 50 are=each placed in stretclied condition in sleeved
relationship about the tube 101 and in overlying relation to
the plurality of cords 103 to thereby hold the cords against
the tube 101.
It is to be noted in FIGS. 16, 18 and 20 LhaL the rings
50 are spaced from one another in the longitudinal direction
of the tubular meniber at successingly greater distances from
L-he distal end 108. Each cord 103 is also provided witli a

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.#10 95/34244 PCTIUS95/01303' - 20 -
series of longitudinally spaced knots 109 agaiilst eacli of
which an elastic ring 50 is placed on the forward side of the
knot. A means for iinparting sliding motion betweeri said
cords and the tubular member is provided by the flexible line
element 105 by which because of its connection to the ends of
the words 103 williin the tubular member 101, a pulliilg force
niay be exerted at its outer end to cause sliding movement
between the cords and the tubular member so as to dislodge
eacli of the elastic rings in desirably controlled sequence.
When tiie pull is applied, a knot 109 acts as a shoulder which
precludes relative movement between the elastic ring and the
cord until the ring is dislodged at the distal end of the
tubular member.
As is best shown in FIG. 16, each cord 103 inclucles a
seginenL- of cord between eacli pair of adjacent elastic rings
wliich his in slack condition and of a length which is equal
to the distance between said pair plus ttie distance from the
distal end of the tube 101 to the ring of the pair whicli is
riearest the distal end 108. It will therefore be seen ttiat
when the cords are pulled a ciistarice which moves ttie forward
ring of the pair to the distal end of the tube and off the
tube, the slack lengt-li of cord suffices to preclude any
movement of the remaining elastic rings. lt is therefore to
be noted that the required pulling force to dislodge a ring
is L-l-iat wliicli is necessary to move a single ring and the
required force does not increase as additional rings are
dislodged.
After tiie cords 103 aiid elastic rings 50 have been loaded
on the rigid tube 101 and positioned thereon as shown in FIG.
16 and 18, it may be a desirable option to place a flexible
sleeve of plastic or a Lextile niaterial L-o fit loosely over
Ltie cords 103 and llie tube 101. Suci- a sleeve, wlien attaclied
at one end to the flexible sectiozi 12 of the endoscope and
extendirig over the cords 103 and elastic rings 50 to
approximately ttie distal eirci of the tube 101, would serve to

CA 02512905 1995-01-31
WO 95/34244 PCT/US95/01305
- 21 -
protect against "sriagging" of the slack segments or loop of
cords beLween Lhe ririgs when the endoscope is in use or
prepared for use.
It is to be uriderstood that the foregoing descriptions of
a preferred embodiment of the itivention has been preserited
for purposes of illustration and explanation and are not
intended to limit the invention to the precise forms
disclosed. For example, a motor coiitrol could be provided
for controlling the movement of the cable 55a in precise
steps. Also, the riurnber of elastic ligating rings 50 or 50a
could be greater or less Llian those illustrated lierein. In
some instances the rings 50a cari be aligned on the textile
tubular member 83 without ridges 84. It is to be appreciated
therefore, that various material and structural changes may
be macle by those skilled in ttie art without departing from
the spirit of the invention.

Representative Drawing