U.S. patent number 3,789,852 [Application Number 05/261,794] was granted by the patent office on 1974-02-05 for expandable trochar, especially for medical purposes.
Invention is credited to Andress Dusseau, Sung Soo Kim.
United States Patent |
3,789,852 |
Kim , et al. |
February 5, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
EXPANDABLE TROCHAR, ESPECIALLY FOR MEDICAL PURPOSES
Abstract
An expandable tubular element, especially for use as a trochar,
in which one or more thin metal strips, such as stainless steel,
are arranged to form a tubular element with the tubular element
being radially expandable and contractible.
Inventors: |
Kim; Sung Soo (Fort Wayne,
IN), Dusseau; Andress (Geneva, IN) |
Family
ID: |
22994900 |
Appl.
No.: |
05/261,794 |
Filed: |
June 12, 1972 |
Current U.S.
Class: |
604/104;
604/164.01; 606/198 |
Current CPC
Class: |
A61B
17/3439 (20130101); A61M 29/02 (20130101); A61M
2025/0024 (20130101); A61B 2017/06085 (20130101) |
Current International
Class: |
A61B
17/34 (20060101); A61M 29/00 (20060101); A61B
17/06 (20060101); A61b 017/34 () |
Field of
Search: |
;128/347-351,341,343,345,214R,215,221,3-9,17,18,20,342 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Truluck; Dalton L.
Attorney, Agent or Firm: Jeffers; Albert L. Rickert; Roger
M.
Claims
1. A trochar comprising an elongated tubular portion open at both
ends having slidable received therein a removable piercing
instrument having a body piercing point protruding from one end of
said tubular portion, said tubular portion being formed of at least
two thin expandable sheet elements concave toward the axis of said
tubular portion and having the circumferential terminal regions in
overlapping relation to define said tubular portion, and adjustable
means disposed at the other end of the tubular portion including
means connected to said concave elements for radially expanding and
retracting the sheet elements to increase or decrease the diameter
of the tubular portion substantially throughout the
2. A trochar according to claim 1 wherein the piercing instrument
is provided with a curved blunt tip portion protruding from one end
of the
3. A trochar according to claim 1 in which one end of said tubular
portion is adapted for insertion into the body, and a guide ring at
the other end of said tubular portion supporting said sheet means
and said adjustable
4. A trochar according to claim 3 in which said adjustable means
includes at least one finger piece connected to said sheet elements
and projecting radially outwardly therefrom, and circumferential
slot elements formed in
5. A trochar according to claim 3 in which said sheet means
comprises at least two elements each of which is in the form of a
sheet of metal doubled back on itself so as to have one end closed
and the other open, each element having a smaller radial thickness
extending from the closed end about half the circumferential length
of the element and the remainder of the circumferential length of
the element having a larger radial thickness, each element being
concave toward the axis of the trochar and the closed end of each
element telescopically engaging the open end of the
6. A trochar according to claim 5 in which stop tabs are provided
on the opposite ends of said elements which interengage with the
stop tabs at the next adjacent element in the position of minimum
telescopic engagement of said elements to prevent said elements
from becoming disengaged from each
7. A trochar according to claim 5 which includes a post fixed to
the radially outer side near the open end of each element and
projecting radially therefrom, an aperture in said guide ring for
each post, a finger piece connected to each element near the closed
end thereof and projecting radially therefrom, and slots formed in
said guide ring and in the radially outer part of the radially
trochar part of each element through which said finger pieces
extend and along which said finger pieces are
8. A trochar according to claim 3 in which said sheet elements
comprises a first sheet element concave toward the axis of said
trochar, and second and third sheet elements concave toward the
said of said trochar and in radially spaced relation and receiving
therebetween the circumferential
9. A trochar according to claim 8 which includes a compression
spring between said second and third sheet elements adapted to
engage the
10. A trochar according to claim 8 in which said first sheet
element comprises a double walled tubular member which is thin in
the radial
11. A trochar according to claim 3 in which said trochar includes
flange
12. A trochar according to claim 11 in which said flanges are
connected to
13. A trochar according to claim 1 which includes means for locking
said
14. A trochar according to claim 1 in which said sheet means is
formed of
15. A trochar according to claim 14 in which said metal is
stainless steel.
16. A trochar according to claim 3 which includes retaining means
retaining the overlapping regions of said sheet means in close face
to face sliding
17. A trochar according to claim 16 in which each said retaining
means comprises an element secured to the radially inner one of
said sheet means and projecting outwardly therefrom and then
axially along the outside of the radially outer one of said sheet
means and slidably engaging the outside of said radially outer one
of said sheet means.
Description
The present invention relates to an expandable and contractible
tubular element, especially for medical purposes and is referred to
herein as a trochar.
Trochars are employed in medical and surgical practice for gaining
access to interior regions of the body for the purpose of draining
fluid therefrom, for the placement of treatment materials therein,
or for the placement of catheters. Also, trochars are employed for
examination purposes in connection with the placement of such
instruments as a peritoneoscope or a thorascoscope. Trochars can be
employed as suprapubic devices to drain distended bladders, or to
place catheters therein.
Trochars are also employed in connection with the evacuation of
fluid from the abdominal cavity, a procedure referred to as
paracentesis, and for the evacuation of fluid from the plural
cavity or the placement of a tube into the plural cavity, a
procedure referred to as thoracentesis.
Most of the foregoing procedures in which a trochar is employed
require the forming of an incision, or a puncture, in a certain
body area and the introduction of the trochar into the body through
the incision or puncture.
In any case, a high degree of skill is required to insert the
trochar into the proper position, especially when the trochar is of
substantial diameter. It will be evident, from the foregoing, that
some trochars, especially those large enough to accommodate an
instrument, such as an optical viewing instrument, must be of
substantial size and the placement of such trochars involves a high
degree of skill on the part of the operator and involves
considerable discomfort to the patient.
With the foregoing in mind, a primary objective of the present
invention is the provision of a trochar which avoids the drawbacks
and difficulties referred to above.
Another object of the present invention is the provision of a
trochar which requires the minimum amount of skill for placement
and involves the minimum amount of discomfort to the patient.
A particular object of the present invention is the provision of a
trochar which can radially be expanded after placement.
Still another object of the present invention is the provision of a
trochar which is radially expansible and which is also
reusable.
It is also an object to provide an expandable trochar so
constructed as to be able to receive a removable puncturing
instrument which will form the puncture to receive the trochar and
which will guide the trochar into position.
A still further object of the invention is the provision of an
expandable trochar having a curved removable blunt shaped guiding
portion which can be used as an urethral dilator or uterine
dilator.
BRIEF SUMMARY OF THE INVENTION
The expandable trochar according to the present invention comprises
a tubular element, especially a stainless steel element, which can
be expanded in the radial direction.
Trochar has been defined in the dictionary as a sharp object
guiding the introduction of a tube into a body-like needle. In
medicine and in this application the term trochar is used to define
in combination a puncture guiding rod cooperating with a tube.
Also, the tube can be referred to as a trochar when the puncture
guiding rod is removed.
The trochar in its simplest form can be a strip of stainless steel
or other suitable material wound up spirally to form the tube with
the free ends of the thus wound up tube being movable in the
circumferential direction to cause expansion and contraction of the
trochar.
In another form which the trochar can take, two tubular stainless
steel elements which are split in the longitudinal direction are
placed in coaxial, coextensive, nesting relation and expansion and
contraction of the trochar is accomplished by varying the diameter
of the inner one of the split tubular elements.
In still another form, which the trochar can take, two or more
strips of stainless steel are folded back on themselves to form
U-shaped members with about half of the length of each member
commencing from the other end whereby, upon forming the members so
as to be arcuate when viewed endwise, the members can be disposed
in mutually telescopic engagement.
In this case, the diameter of the trochar is adjusted by adjusting
the degree of telescopic engagement of the members with each
other.
In yet another form which the trochar can take, a tubular stainless
steel element is flattened out and is then formed to an arcuate
configuration and the ends thereof are inserted between a pair of
spaced parallel curved stainless steel strips to form the tubular
trochar. In this case, the diameter of the trochar is adjusted by
adjusting the degree of telescopic engagement of the ends of the
first mentioned sheet with the last two mentioned parallel
sheets.
In every case, the trochar is tubular so that it can receive a
removable piercing instrument. The trochar at the end opposite the
end which is introduced into the body, has a guide ring which
supports the elements of the trochar and permits manipulation
thereof and the securing thereof to the body.
The foregoing objects as well as still other objects and advantages
of the present invention will become more apparent upon reference
to the following detailed specification taken in connection with
the accompanying drawings in which:
FIG. 1 is a side elevational view of a trochar according to the
present invention in radially collapsed position and with a
puncture device mounted therein.
FIG. 2 is a side elevational view similar to FIG. 1 but showing the
trochar in maximum expanded position.
FIG. 3 is a plan sectional view indicated by line III--III on FIG.
1.
FIG. 4 is a view like FIG. 3, but shows the trochar in maximum
expanded condition.
FIG. 5 is a fragmentary sectional view indicated by line V--V on
FIG. 1, showing a guide member forming a part of the trochar.
FIG. 6 is a fragmentary plan view drawn at enlarged scale and
showing tab elements which limit the expandability of the
trochar.
FIG. 7 is a plan sectional view, showing a modified form which a
trochar according to the present invention can take.
FIG. 8 is a plan sectional view, showing a further
modification.
FIG. 9 is a plan sectional view, showing a still further
modification.
FIG. 10 is a plan sectional view of still another modification.
FIG. 11 is a fragmentary sectional view showing a device for
locking the trochar in adjusted positions of expansion thereof.
FIG. 12 is a fragmentary view showing a modified form of the
guiding portion for the trochar when used as a dilator.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings somewhat more in detail, the trochar of
FIGS. 1 through 6 will be seen to comprise a rather elongated
tubular portion indicated at 10 which is contractible to its FIGS.
1 and 3 positions and expansible to its FIGS. 2 and 4
positions.
The trochar when in its FIG. 1 position is hollow from end to end
and can receive a removable piercing instrument 12 with a piercing
point, or needle, 14. The end of the tubular portion of the trochar
which is adjacent point 14, may be beveled or tapered as at 15 to
facilitate introduction of the trochar into a puncture made by
point 14.
The end of the trochar opposite point 14, namely, the outer end of
the trochar, is provided with a guide ring 16 which is flanged at
18 as shown in FIGS. 1 and 2. Guide ring 16 is provided with slot
means 20 in which is slidable rod means or post means or finger
piece means 22 extending in the radial direction of the
trochar.
Reference to FIG. 3, will show more in detail the various elements
of the trochar. The tubular portion 10 of the trochar is formed of
two elements 24, each of which is a stainless steel strip or other
suitable material folded back on itself so as to have a closed end
at 26 and an open end at 28. Commencing at the closed end, about
half the length of each element is formed to a smaller radial
dimension, while the remainder of each element is formed to a
larger radial dimension. Each element is formed concentrically
about the longitudinal axis 30 of the trochar and the smaller end
of each element telescopically engages the larger end of the other
element. The elements are formed of thin corrosive resistant metal,
such as stainless steel, and are thus flexible.
Attached to the larger end of each of the elements on the radially
outer side is a post 32 extending radially outwardly through a
pertaining aperture 34 in guide ring 16.
Also attached to each element near the closed end thereof and on
the radial outer side is the rod or post, or finger piece, 22
extending radially outwardly through the circumferential slot 20 in
guide ring 16 and also through a circumferential slot 40 in the
radially outer side of the larger end of the other element. By
manipulating finger pieces 22 along their slots 20, the degree of
telescopic engagement of the elements with each other can be
adjusted and this will adjust the diameter of the trochar. The
finger pieces 22 are threaded at 21 and a lock nut 23 serves to
lock the trochar in adjusted position.
FIG. 3 shows the trochar in maximum collapsed, minimum diameter,
position and FIG. 4 shows the trochar in maximum expanded, maximum
diameter, position and also shows the manner in which finger pieces
22 are adjusted in guide ring 16 to accomplish the expansion and
contraction of the trochar.
It is advantageous for the closed end of each element to have
connected thereto an angle piece, or side bar, 42 as shown in FIG.
5 extending outwardly through the adjacent slot 40 in the other
element and then downwardly along the outside of the other element,
thereby retaining the outer part of each of the said elements in
close engagement with the inner part of the other element which is
telescopically engaged therewith.
FIG. 6 will show that the free ends of the longer end of each
element are advantageously provided with turned in edges, or tabs,
44 which cooperate with turned out tabs 46 near the closed ends of
the other elements, thereby to limit the expanding movement of the
trochar and to prevent the telescopically engaged elements from
becoming disengaged.
FIG. 11 shows how a modified lock arrangement could be mounted on
each finger piece 22 to lock the trochar in adjusted position. The
lock arrangement comprises a nut 48 threaded to tubular element 50
so that the nut can be tightened up to clamp the respective finger
piece 22 fixedly to guide ring 16 in any adjusted position of the
finger piece.
In FIG. 7, a stainless steel tube is flattened out and formed to an
arcuate shape to form a double walled tubular member as indicated
at 60 with the ends thereof telescopically engaged between a pair
of parallel arcuate sheets 62 and 64. Finger pieces 66 on the ends
of the element 60 are disposed in slots in sheet 64 and can be
employed for adjusting the diameter of the trochar. In this
modification, a spring 68 may be disposed between sheets 62 and 64
and engages the ends of element 60 when the diameter of the trochar
is reduced and urges the said ends outwardly. The spring 68 may be
omitted if desired and the finger pieces 66 can be utilized to
expand the trochar.
FIG. 8 shows a modification similar to that first described except
three folded sheet elements 70, 72 and 74 are arranged in
telescopic engagement. The diameter of the trochar of FIG. 8 can be
adjusted in the same manner as in respect of the first described
modification, except that the FIG. 8 modification has three
adjustable finger pieces 76, 78 and 80.
FIG. 9 shows a modification in which there is mounted within guide
ring 82, an outer tubular element 84 split down one side at 85
while inside element 84 is an inner tubular element 86 split down
the opposite side at 87. The free ends of inner element 86 are
provided with finger pieces 88 extending radially through
circumferential slots provided therefor in outer element 84 and
guide ring 82 to permit expansion and contraction of the
trochar.
FIG. 10 shows a modification in which a single strip 90 of
stainless steel is wound up in a spiral to form a tube with finger
pieces 92 connected to the inner and of the spiral and extending
radially outwardly through a slot formed in the other convolutions
of the spirally wound sheet. A post 93 is provided and serves the
same purpose as previously described. By adjusting the finger
pieces relative to the outer end of the wound up sheet, the
diameter of the trochar can be adjusted.
Finally, FIG. 12 shows a modification in which a blunt shaped
guiding portion 96 having an obliqued or curved blunt tip portion
97 is provided for substitution of the sharp tipped piercing
instrument 14. The trochar with the curved tip guiding portion 96
is used as a uterine or urethral dilator. After placement of the
trochar in the desired position the tube can be expanded in the
same manner as previously described.
All of the trochars described are tubular for receiving a
puncturing or guiding instrument, and all are adjustable as to
diameter, and all can be provided with locking means to lock the
trochar in adjusted positions.
The invention has been described with reference to particular
modifications but it will be understood that modifications may be
made within the purview of the appended claims.
* * * * *