Note: Descriptions are shown in the official language in which they were submitted.
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MYRINGOTOMY INSTRUMENT
FIELD OF THE INVENTION
The present invention relates in general to myringotomy. More
particularly, the present invention relates to an instrument providing for
incising
the eardrum, suctioning the fluid released from the middle ear passage and
positioning the tympanostomy tube in place.
BACKGROUND OF THE INVENTION
Treating middle ear infection, or otitis media occasionally involves a
surgical operation in which an incision is made through the tympanic membrane.
Any fluid and/or usually thickened secretions are removed. A tympanostomy
tube is typically inserted into the incision to keep the middle ear passage
aerated and permit drainage of fluid to the outer ear meatus. Normally such an
operation requires a number of devices to be employed by a surgeon who, as a
result, occasionally must redirect his/her line of vision from the patient's
ear. An
integral instrument providing for a significant number of activities typically
associated with such an operation may aid the surgeon to remain focused in the
patient's ear during the operation process.
U.S. Patent 3,913,584 discloses an instrument providing for most of
the activities typically performed during myringotomy and the insertion of
tympanostomy tube into the eardrum. The disclosed device consists of an outer
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sleeve surrounding an inner tube. The inner tube, the distal end tip of which
is
sharpened, is adapted for releasably holding the tympanostomy tube across its
distal end, such that its sharpened end tip protrudes from the tympanostomy
tube outwards. The inner tube also provides for suctioning the fluid released
from the middle ear passage following the incision made in the tympanic
membrane by means of its sharpened tip. The tympanostomy tube is released
from the inner tube and placed through the incision by means of the moveable
sleeve. However, the disclosed device does not provide the surgeon with the
required control for correctly positioning the tympanostomy tube through the
incision in the eardrum. Furthermore its sharpened tip may harm the patient's
ear and/or the surface of the tympanostomy tube. Therefore, a more user-
friendly instrument providing for orienting and positioning of the
tympanostomy
tube in the eardrum that is less hazardous to the ear passages and or the
tympanostomy tubes is called for.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is an isometric view of a myringotomy instrument according to a
preferred embodiment of the present invention;
Fig. 2 is an isometric view of a segment of the device for incising,
suctioning and tympanostomy tube holding of the myringotomy instrument
shown in Fig. 1;
Fig. 3 is a sectional view of the segment of the device for incising,
suctioning and tympanostomy tube holding shown in Fig. 2;
Fig. 4 is a front side view of the distal end of the myringotomy
instrument shown in Fig. 1;
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Fig. 5 is an isometric view of the proximal segment of the device for
incising, suctioning and tympanostomy tube holding of the myringotomy
instrument shown in Fig. 1;
Fig. 6 is a sectional view of a segment of the myringotomy instrument
shown in Fig. 1; and
Fig. 7 is a schematic presentation of a tympanosomy tube on which an
auxiliary spacer is placed.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
In accordance with the present invention an instrument for performing
myringotomy operations is provided. The instrument of the invention provides
for
incising the tympanic membrane, suctioning the fluids released from the middle
ear passage and positioning the tympanostomy tube (TT). An instrument
provided in accordance with a preferred embodiment of the present invention is
hereby described with reference to Figs 1- 3. All the directional notations
such
as upwards or downwards referred to hereinafter relate only to the scenario
indicated in the referenced drawings, as the devices in reality can be
arbitrarily
oriented in any direction. In Fig. 1 an isometric view of instrument for
performing
myringotomy 8 consisting of a device for incising, suctioning and grasping a
TT
(ISGTT) 10 attached to gripping handle 12 is shown. ISGTT 10 has external
tube 14 in which the TT holder and the incising blade, both not shown, are
installed. Gripped TT 16 protrudes from the distal end of ISGTT 10. The length
of extemal tube 14 is such that the distance between the distal end of ISGTT
10
and distal surface of gripping handle 12, referred to hereinafter as the
clearance
length, exceeds a predefined value. Typically the clearance length is not
smaller
than 8 centimetres. Therefore, the clearance between the patient's ear and
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gripping handle 12 provides the surgeon with conveniently rotating and
translating ISGTT 10 within the external ear passage without blocking the line
of
sight. The incising blade is drawn outwards and is withdrawn through bore 17,
by means of blade positioning selector 18 located at the proximal end of ISGTT
10. Lever 20 that is pivotally connected to the upper side of gripping handle
12
provides for grasping and releasing TT 16 and for pushing TT 16 through the
incision made in the tympanic membrane, as is further described infra.
Negative
pressure for suctioning is provided through aperture 24 by means of a vacuum
tube of prior art, not shown, when slip fitted into aperture 24. Fluids and
air
passageway, not shown, connects between aperture 24 and the lumen of the
pushing and suctioning member (PS) of the TT holder, not shown. The lumen of
the PS has a fluid connection with bore 17, as is further described infra. The
sealing of working aperture 26, which is an additional aperture of this
passageway, by a user's finger, effects negative pressure at the distal end of
bore 17.
In Fig. 2 an isometric view of a segment of the ISGTT shown in Fig. 1
is shown. Out of the distal end of external tube 30 TT holder 32 is forwardly
protruding. A TT holder of the invention typically consists of a gripper, a PS
and
a base. A gripper according to the invention has an engaging surface
surrounding the tubular segment a TT for its grasping. The gripper in
accordance with a preferred embodiment of the present invention consists of
tube 34 whose distal end is furcated into a circle of inwardly bendable
fingers
36. PS 38 is another tube coaxially disposed within the lumen of tube 34. TT
40
is appended to PS 38 such that its bore is coaxial with PS 38. In Fig. 3 a
sectional view of the segment of the ISGTT described above is shown. External
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tube 50 surrounds tube 52 of the gripper, while the gripper is translatable
within
tube 52. Circle of fingers 54 the outside surface of which is conical,
protrudes
out of the distal end of tube 50. Inwardly protruding teeth 56 of fingers 54
provides for clutching TT 58 attached to the distal end of PS 60 and for
sealing
5 the connection between TT 58 and PS 60. The inner surfaces of teeth 56
constitute a divided engaging surface of the gripper. The external diameter of
PS 60 conforms with the inner diameter of tube 52 except for its extreme end
the diameter of which equals the diameter of the tubular segment of TT 58.
Clearance 62 provides for inwardly bending fingers 54 and for forcing
respective
surfaces of teeth 56 against the surface of TT 58, when moved backwards in the
direction of arrow 64 into a gripping position. Alternatively, a gripper
consists of
one or more rings the diameter of which is changeable, or gripping fingers
translatable in directions normal to the axis of the TT. Incising blade 66 is
disposed in the lumen of PS 60. The blade is connected by means of a shaft,
not shown, to blade positioning selector 18 shown in Fig. 1 to which reference
is
again made.
Reference is now made to Figs 4 - 6 in which further details of the
ISGTT shown in Fig. 1 are provided. In Fig. 4 a front side view of the ISGTT
is
shown. Blade 80 that is attached to shaft 82 is either drawn out of bore 86,
or
withdrawn into the lumen of the PS, not shown. Bore 86 is centered at the
distal
face of TT 84. Typically, the diameter of the external tube surrounding the
gripper and the maximal diameter of the cone formed by the outermost surfaces
of the gripper fingers when fully retracted do not exceed the diameter of the
distal surface of TT 84. Namely, the distal segment of the ISGTT ranging from
its distal end up to the surface of the gripping handle is confined by a
cylindrical
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projection of TT 84 coaxial with bore 86. Therefore, the external surface of
TT
84 is the front end of an ISGTT of the invention facing any part of an ear of
a
patient in the course of the surgical process, whenever the incising blade is
withdrawn. Furthermore, the external tube and/or the ISGTT may touch the oval
speculum typically employed for maintaining sterility and protecting the ear
only
by one of its points.
In Fig. 5 blade positioning selector 100 is shown. Lever 102 is
attached to shaft 104 that is further connected on its other end to the
incising
blade, not shown. Biasing spring 106 provides for retracting lever 102 and
therefore withdrawing the incising blade back into the lumen of the PS, not
shown. Pushing lever 102 in the direction of arrow 108 draws the incising
blade.
Stopper 110 resiliently attached to frame 111 is released when forced by lever
102 in this direction. Lever 102 is continuously moved further up to the point
that
stopper 110 faces recess 112. It is sprung into recess 112 whereby the
movement of lever 102 is stopped. At this position, which is the drawn
position,
the incising blade is drawn out to its full extent. Releasing stopper 110 by
means
of lever 114 causes lever 102 to retract to its initial position and
concomitantly
withdraw the incising blade. In a drawn position the length of the segment of
the
incision blade protruding out of the TT is not smaller than a predefined
drawing
length. Thus the TT and/or the ISGTT do not block the line of sight of the
surgeon who may conveniently incise the tympanic membrane. A drawing
length of two centimetres normally conforms to the small diameters of the
above-mentioned speculums.
In Fig. 6 a sectional view of a segment of the instrument for performing
myringotomy shown in Fig. 1 is shown. External tube 130 and frame 132 of
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ISGTT 134 are attached to gripping handle 136. Gripper 138 and PS 140 are
attached to TT holder base 142. Optionally gripper 138 and PS are also
attached to each other. TT holder 141 is movably disposed in the lumen of
external tube 130. The lumen of PS 140 is hermetically sealed except for the
aperture, not shown, in its distal end and the longitudinal aperture 144
leading to
the fluid and air passageway 146. Lever 148 is connected to gripping handle
136 by hinge 150. One end of lever 148 is engaged in recess 152 located at the
bottom of TT holder base 142, whereas its other end is downwardly protruding.
Therefore, translational motion of TT holder 141 in the directions of arrows
153
or 154 is imparted by respective pivotal rotations of lever 148. Shaft 155
connecting the incising blade and the blade positioning selector is movably
disposed in the lumen of PS 140. Optionally o-rings 158 hermetically seal
apertures 159 and the connection between gripping handle 136 and PS 140
respectively. One or more spacers such as spacer 160 are optionally disposed
in the lumen of PS 140 for keeping shaft 154 coaxial with PS 140. The gripper
and the PS can be moved independently according to the invention, such as by
employing separate bases instead of common TT base holder 142, an
engagement mechanism and one or two pivotal and or translational dedicated
levers, as known in the art.
For operating an instrument for performing myringotomy of the
invention first a TT must be inserted and gripped by the distal end of the
ISGTT.
For this purpose a TT is vertically placed having its distal face on a
horizontal
surface. The gripper is opened by pulling lever 148 to its maximal extent in
the
direction of arrow 153. Then the tubular segment of the TT is inserted into
the
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clearance surrounded by the fingers of the gripper such that the distal face
of
the PS engages the TT.
Optionally, an auxiliary spacer is employed, as can be seen in Fig. 7 to
which reference is now made. TT 190 is vertically posted having spacer 192
placed over flange 194. The width of spacer 192 conforms to the difference
between the length of tubular segment 196 and the distance between the distal
end of the ISGTT and the distal face of the PS. Reference is again made to
Fig.
6. The distal end of the ISGTT is pressed against the spacer while lever 148
is
concomitantly pushed to its maximal range in the direction of arrow 154. At
this
stage in which the TT is gripped and the gripper and the TT holder are in a
retracted position the instrument for performing myringotomy is ready to be
inserted into an external ear passage of the treated patient.
Reference is again made to Fig. 1. Range selector 180 provides for
limiting the pivotal rotations of lever 20 such that three distinct positions
of the
gripper are provided. When range selector 180 is pulled outwards as is shown
in
Fig. I lever 20 can be rotated up to its maximal extents in the directions of
arrows 182 and or 184 respectively. For gripping a TT, lever 20 is maximally
rotated in the direction of arrow 184 by which the gripper moves to an open
position. Then lever 20 is maximally rotated in the opposite direction to
bring the
gripper into a retracted position, as is described hereinabove. At a retracted
position selector 180 is pushed inwards which results a limited rotational
angle
in the direction of arrow 182. Rotating lever 20 by such an angle causes TT 16
to be pushed away from aperture 186 by a distance conformal to the length of
the tubular segment of TT 16. At this stage in which the gripper is in an
intermediate gripping position TT 16 is still being held by the gripper
providing
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for improving the positioning of TT 16 through the incision made in the
eardrum.
Two stoppers, not shown, limit the translational range of the TT holder in
both
directions, which in turn limit the angles of respective pivotal rotations of
lever
20.
The ISGTT of the invention is normally made of materials such as
stainless steel or plastic resins typically employed for manufacturing
disposable
medical devices. The gripping handle is typically made of such plastic resins.
Mounting of a ISGTT onto a gripping handle need not be limited to the
manufacturing phase of an instrument for performing myringotomy of the
invention but can be also carried out by a user prior to its usage in the
operating
room.
