5,301,684
1 2
other end to the plunger, the flap being shaped to tend
BIOPSY NEEDLE to spring outwardly from the plunger.
The interior of the tubular body preferably has a
BACKGROUND OF THE INVENTION circular cross section so that the plunger is rotatable as
The subject of this invention is a needle for perform 5 wel1 38 slidable in the tubular body,
biopsies, i.e. for removal of pieces of tissue from human The handle is tubular and may thereupon be formed
or animal bodies. The needle which is the subject of this with a slot having two axially disposed portions circum
application is of particular use in performing pleural ferentially spaced and connected at their distal ends by
biopsies. a circumferential portion, one of the axially disposed
Needles for performing biopsies are well known and 10 slot portions being open at its proximal end. The
normally comprise a probe which carries near the distal plunger presents a pin engaging the slot, the position of
end a scoop projecting from the side of the probe, a the pin on the plunger and the positions of the various
biopsy being performed by inserting the probe through portions of the slot with respect to the tubular body
an incision made in the skin and pressing the probe into being such that when the pin on the plunger is engaged
the body far enough for the scoop to reach the position 15 with the open ended axial portion of the slot the flap is
of the body from which a portion is to be removed. The circumferentially displaced from the aperture in the
probe is then withdrawn, the scoop entraining a portion tubular body. The length of this axial portion is such
of the tissue of the body, and as the probe is removed that, when the pin is at the distal end of the slot, the flap
this portion of tissue held by the scoop is brought back is nearer the distal end of the tubular body than the
out for medical examination. Such known biopsy nee- 20 aperture wnae behig still circumferentially displaced
dies suffer from the disadvantage that their results are from the aperture. Rotating the plunger so that the pin
extremely unpredictable and in fact usually a suitable moves the circumferential portion of the slot to
portion of tissue is removed in little more than 70% of the end where it joins the ^ of the slot brings
such biopsy operations. Even when a satisfactory por- ^ flap mt0 line with the aperture although the flap is
tion of tissue is removed, this frequently is accompanied 25 ^ ... ^ ^ end Qf ^ ... ^ than ±e
by a piece of unwanted tissue Also, the probe may cause aperture. 7^ retracting the plunger along this other
more damage than necessary to surrounding tissue and ^ ^ of the s,ot tQwards the M en(J of the
.f the tissue sample obtained ,s unsatisfactory, the needle ^ bfm ^ fl ^ ... rfi m ^
must be re-inserted into the body and a fresh attempt ... the flap to swing ouVand project
made to obtain a satisfactory tissue sample. 30 3 r " * J
The International Patent Publication No. WO thr°"ShKthe aPertu£- ... . t 89/05608 discloses a biopsy needle which gives a high . Th,s ... needle< wh?e constituting a significant degree of success in removing satisfactory samples afa TMPTM««ent over prior known biopsy needles, has first attempt, a success rate normally well above 90%, been found to present the drawback that the plunger, and which readily removes cleanly a sample of wanted 35 whlch fits loosely wltmn the tubular »»dy, can easily tissue without dragging with it portions of unwanted rotate and slldab,v translate within tube, and can theretissue, fore change the relative positions of the flap and aper
A biopsy needle according to this disclosure incorpo- ture or even accidentally become disengaged from the
rates an elongated body pointed at one end having a tubular body.
tissue-removing edge directed backwardly from the 40 SUMMARY OF THE INVENTION pointed end. The tissue-removing edge is formed on a
flap supported by the body and is movable between a 11 is a principal object of the present invention, thereretracted position, in which the tissue-removing edge fore'to provide a biopsy needle of the type disclosed in lies within the lateral confines of the body, and an ex- the International Patent Publication No. WO 89/05608 tended position in which the tissue-removing edge lies 45 which does not exhibit the disadvantages referred to beyond the lateral confines of the body. above.
The proximal end of the needle, i.e., the end remote This object, as well as further objects which will
from the pointed end, is formed as a handle supporting become apparent from the discussion that follows, are
operating means coupled to the flap and operative to achieved, in accordance with the present invention, by
move the flap from the retracted position to the ex- 50 providing a spring, such as a helical compression spring,
tended position and vice versa. between the plunger and the tubular body, so as to
The operating means includes a means to lock the flap present a spring tension between these two elements
in the chosen position. tending to maintain their relative positions.
The flap may be formed as a flat flap or may be Advantageously, the slot on the tubular body which
curved in the form of a scoop. 55 engages the locating pin on the plunger includes a notch
The tissue-removing edge may be formed as a at approximately the center portion thereof. This notch
straight edge or may be formed with serrations. in the slot serves as a detent for the plunger and pin to
The flap is mounted on a plunger slidable within the hold the same in position,
tubular body. The wall of the tubular body in this con- For a full understanding of the present invention,
struction is formed with an aperture with which the flap 60 reference should now be made to the following detailed
may be brought into register by an appropriate sliding description of the preferred embodiments of the inven
movement of the plunger. tion as illustrated in the accompanying drawings.
The flap is pivoted at one end to the plunger and is wiw«
spring-urged to swing outwardly from the plunger, the BRIEF DESCRIPTION OF THE DRAWINGS tissue-removing edge being at the end of the flap remote 65 FIG. 1 illustrates a tubular body portion of the biopsy from the pivot. In an alternative construction the flap needle according to the invention,
may be formed of spring material, is formed at one end FIG. 2 illustrates a plunger movable through the with the tissue-removing edge and is attached at the tubular body portion.
