Advancer for surgical instrument

A device for axially advancing a surgical instrument into the brain of a patient includes an advancer that is engageable with the gooseneck of a surgical apparatus. The is axially telescoping, and the advancer can selectively grip the surgical instrument. Accordingly, the surgical instrument can be gripped by the advancer and the advancer telescoped to advance the instrument into the brain along a predetermined path.

FIELD OF THE INVENTION 
The present invention relates generally to neurosurgery instruments, and 
more particularly to devices for advancing neurosurgery probes into a 
patient. 
BACKGROUND 
To perform neurosurgery, it is typically necessary to advance a 
neurosurgical instrument, e.g., an endoscope, scalpel, etc. into the brain 
of a patient. The instrument is advanced into the brain until the operable 
portion of the instrument is positioned adjacent the site of interest, 
i.e., the site of the brain to be operated on. Then, the instrument is 
manipulated as appropriate for performing the particular procedure. 
Modern neurosurgery techniques fall into two general categories. The first 
is relatively invasive and involves removing a large portion of the 
patient's skull, to gain access to the brain. After surgery, the portion 
of the skull which was removed is replaced. 
The second type of neurosurgery, referred to herein as neuroendoscopy 
because it often permits advancing an endoscope into the brain to provide 
the surgeon with a view of the brain, is much less traumatic to the 
patient than the first. Neuroendoscopy requires drilling a small hole in 
the skull, and then advancing one or more surgical instruments and/or 
endoscopes through the hole into the brain to perform the operation. 
Neuroendoscopy is preferred when use of it is practicable, for the reason 
that it causes relatively little trauma to the patient and allows for 
relatively rapid patient recovery. 
Not surprisingly, in neuroendoscopy the surgical instrument or instruments 
must be advanced along a precisely determined path into the brain, to 
avoid unintentionally damaging the brain. Also, once precisely positioned 
in the brain, the instruments must be securely held in position, again to 
avoid unintentional injury to the brain. 
To aid the surgeon in advancing an instrument or probe along a precisely 
predetermined path, devices referred to as stereotactic frames have been 
introduced. A stereotactic frame can be positioned near the patient's 
skull prior to surgery, and the frame has one or more surgical instrument 
holders, each of which can securely grip a surgical instrument or probe 
and hold the probe in a predetermined orientation relative to the brain. 
One type of stereotactic device is the Bookler Laparascopic Scope Holder 
made by Flex-Bar Machinery Corporation of New York. The Bookler Scope 
Holder has a flexible arm that has a fixed end which is mounted on a 
frame. The flexible arm, sometimes referred to as a gooseneck, has a free 
end, and the free end can be moved in any direction in three dimensional 
space relative to the frame, and can be locked relative to the frame once 
the free end has been placed in the desired position and orientation 
relative to the frame. 
A neurosurgery instrument holder is connected to the free end of the 
gooseneck, such that a neurosurgery instrument can be engaged with the 
holder of the gooseneck. The instrument can thus be oriented relative to 
the frame as desired. To orient the instrument relative to the frame, the 
free end is unlocked, the instrument moved as desired, and the free end 
locked again in position. 
It can be appreciated in reference to the above discussion that once a 
neurosurgery instrument has been engaged with the holder of the gooseneck 
and oriented as desired, the free end of the gooseneck must be unlocked to 
permit advancing the instrument along the predetermined path. Unlocking 
the free end, however, as discussed above, permits movement of the 
instrument in all three spatial dimensions. 
This is undesirable, because it results in difficulty in simply advancing 
the instrument axially into the brain, while maintaining the orientation 
of the instrument relative to the brain. Stated differently, each time it 
is desired to move the instrument axially into the brain along the 
predetermined path, the free end of the gooseneck must be unlocked, 
permitting unintentional movement of the instrument in the remaining two 
dimensions and potentially causing the instrument to deviate from the 
predetermined path of advancement. 
Accordingly, it is an object of the present invention to provide a device 
for permitting movement, in only a single direction, of a surgical 
instrument that is held by a surgical apparatus. Another object of the 
present invention is to provide an adaptor for engaging the holder of the 
flexible arm of a surgical apparatus and for selectively gripping a 
surgical instrument. Another object of the present invention is to provide 
an adaptor for connecting a surgical instrument to a surgical apparatus, 
that is easy to use and cost-effective to manufacture. 
SUMMARY OF THE INVENTION 
A device is disclosed which is engageable with a surgical apparatus for 
axially advancing a surgical instrument into a patient. The device of the 
present invention includes a telescoping advancer which is engageable with 
the surgical apparatus. As intended by the present invention, the advancer 
is movable from a shortened configuration, wherein the advancer has a 
first length, to an extended configuration, wherein the advancer has a 
second length longer than the first. The advancer includes a gripping 
element for gripping the surgical instrument, such that the surgical 
instrument is advanced axially into the patient when the advancer is moved 
toward the extended configuration. 
In another aspect of the present invention, an axial advancer for advancing 
a neurosurgery instrument into the brain of a patient includes an annular 
adaptor for engaging a surgical apparatus. The adaptor defines an axis, 
and a hollow holder is slidably disposed in the adaptor coaxially with the 
adaptor. 
Also, an annular resilient gripping element is disposed in the holder 
coaxially with the holder. In accordance with the present invention, the 
gripping element is biased to a normal configuration, wherein the gripping 
element has a first inside diameter that is sufficiently large to permit 
the surgical instrument to be positioned within the gripping element. 
Additionally, the gripping element has a gripping configuration, wherein 
the gripping element has a second inside diameter smaller than the first, 
for gripping the surgical instrument. 
Further, a cap is threadably engaged with the holder for selectively moving 
the gripping element to the gripping configuration to grip a surgical 
instrument. Moreover, a handle is threadably engaged with the holder and 
is rotatably engaged with the adaptor for selectively moving the holder 
axially relative to the adaptor. When the surgical instrument is gripped 
by the gripping element and the handle is rotated in a predetermined 
direction, the surgical instrument is axially advanced into the patient's 
brain. 
Preferably, the holder is formed with a seat, and the cap can be rotated to 
urge the gripping element against the seat and thereby move the gripping 
element to the gripping configuration. Also, the holder has a longitudinal 
slot formed in it, and the advancer includes a retaining pin which is 
attached to the adaptor and which protrudes through the slot to retain the 
holder within the adaptor. 
As further intended by the present invention, the holder has an inner 
surface and an outer surface, and a portion of the inner surface is 
threaded for engaging the cap. Further, a portion of the outer surface of 
the holder is threaded for engaging the handle. 
In the presently preferred embodiment, the adaptor is configured for 
engaging an instrument holder on a flexible arm of a surgical apparatus. 
In another aspect of the present invention, a device for moving a surgical 
instrument axially relative to a surgical apparatus has an adaptor for 
engaging the surgical apparatus and a holder slidably disposed in the 
adaptor. Also, the device has a gripping element that is disposed in the 
holder and is selectively movable between a normal configuration, wherein 
the gripping element does not grip the surgical instrument, and a gripping 
configuration, wherein the gripping element can hold the surgical 
instrument stationary relative to the holder. 
In yet another aspect of the present invention, a method is disclosed for 
axially advancing a neurosurgery instrument into the brain of a patient 
along a predetermined path. The method of the present invention includes 
the steps of providing a surgical apparatus which is positionable in a 
predetermined orientation relative to the brain. Also, an advancer is 
provided which has an extended configuration and a shortened 
configuration, and the advancer holds the instrument. 
In accordance with the method of the present invention, the advancer is 
engaged with the surgical apparatus, and the surgical instrument is 
engaged with the advancer such that the surgical instrument is oriented 
along the predetermined path of advancement into the brain. The advancer 
can then be moved toward the extended configuration to advance the 
instrument into the brain along the predetermined path. 
The details of the present invention, both as to its construction and 
operation, can best be understood in reference to the accompanying 
drawings, in which like numerals refer to like parts, and which:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring initially to FIG. 1, an advancer for axially advancing a surgical 
instrument into a patient is shown, generally designated 10. As shown, the 
advancer 10 has a generally cylindrical adaptor 12 that can fit snugly 
within an annular holder 14 of a surgical apparatus, generally designated 
16. Preferably, the advancer 10 is made of a rigid, lightweight, 
low-friction hard plastic or metal material. More preferably, the advancer 
10 is made of anodized aluminum, polycarbonate, or steel, and can be made 
by machining or molding processes well-known in the art. 
In one presently preferred embodiment, the surgical apparatus 16 is a 
Bookler Laparascopic Scope Holder made by Flex-Bar Machinery Corporation 
of New York. Such an apparatus includes a flexible arm 18 (familiarly 
referred to as a gooseneck) having a free end 20, and the free end 20 can 
be moved in space to orient the holder 14 as desired. Also, the arm 18 can 
be locked to prevent motion of the free end 20. 
FIG. 1 further shows that the advancer 10 can hold a surgical instrument 
22. In one presently preferred embodiment, the surgical instrument 22 is a 
neuroendoscope. It is to be understood that the surgical instrument 22 can 
be another type of surgical instrument, e.g., a probe, an endoscopic 
scalpel or forceps, etc. 
In accordance with the principles of operation of a Bookler Laparascopic 
Scope Holder, the arm 18 can be moved as appropriate to orient the holder 
14 as desired to establish a predetermined path of advancement of the 
surgical instrument 22 into a patient, e.g., into the brain of a patient 
incident to neurosurgery. As will be more fully appreciated after further 
discussion below, the advancer 10 can telescope axially to advance the 
surgical instrument 22 into the patient (i.e., in the direction of the 
arrow 24), without requiring the unlocking of the arm 18 of the surgical 
apparatus 16. 
Now referring to FIGS. 2 and 3, the details of the advancer 10 can be seen. 
As shown in FIGS. 2 and 3, the components of the advancer 10 described 
below are coaxial, i.e., all the hollow or annular components described 
below share a common axis 11. 
FIGS. 2 and 3 show that the advancer 10 includes the adaptor 12, and the 
adaptor 12 has a hollow cylindrical adaptor skirt 26 and an annular flange 
28 formed integrally with the adaptor skirt 26. The adaptor skirt 26 is 
configured to fit snugly within the holder 14 (FIG. 1) in an interference 
fit therewith. 
FIGS. 2 and 3 further show that the advancer 10 includes a hollow 
instrument holder 30. Preferably, the instrument holder 30 is made of a 
unitary piece of rigid material. The instrument holder 30 has a hollow 
cylindrical holder skirt 32 which can slide within the adaptor 12. Also, 
the instrument holder 30 has a hollow cylindrical engagement segment 34 
that has a larger outside diameter than the holder skirt 32, and a portion 
36 of the outer surface of the engagement segment 34 is threaded. 
As intended by the present invention, slidable motion of the instrument 
holder 30 within the adaptor 12 is mechanically limited by the structure 
described below. More specifically, as shown best in FIG. 3, a face 38 of 
the engagement segment 34 of the instrument holder 30 can abut the adaptor 
flange 28, to prevent movement of the face 38 past the flange 28 in the 
direction of the arrow 39 in FIG. 3. Additionally, FIGS. 2 and 3 show that 
a slot 40 is formed longitudinally in the holder skirt 32, and a retainer 
pin 42 extends into the slot 40. As shown, the retainer pin 42 is fixedly 
mounted in an orifice 44 that is formed in the adaptor 12. The pin 42 can 
abut a stop 46 that is formed on the instrument holder 30, to prevent 
motion of the pin 42 past the stop 46 in the direction opposite that 
indicated by the arrow 39. To hold the pin 42 within the orifice 44, the 
pin 42 can be threaded or glued to the adaptor 12. The pin 42 also 
prevents rotation of the instrument holder 30 so that the holder 30 will 
not rotate as is axially advances (i.e., as it undergoes longitudinal 
translation). 
Still referring to FIGS. 2 and 3, the advancer 10 includes a hollow, 
resilient cylindrical gripping element 48. Preferably, 180 the gripping 
element 48 is a compressible gland seal made of silicon or other rubber 
material. 
As shown, the engagement segment 34 has a seat 50, and an end 52 of the 
gripping element 48 abuts the seat 50. As will be more fully disclosed 
below, when the end 52 of the gripping element 48 is urged against the 
seat 50, the gripping element is deformed to enable the gripping element 
48 to hold the surgical instrument 22 stationary with respect to the 
instrument holder 30. 
To provide for urging the gripping element 48 against the seat 50, 
compression element e.g., a hollow cap 54 is threadably engaged with the 
engagement segment 34 of the instrument holder 30. More specifically, an 
outside surface 56 of the cap 54 is threaded, and the surface 56 is 
threadably engaged with a threaded portion 58 of the inside surface of the 
engagement segment 34. Accordingly, the cap 54 can be rotated as 
appropriate to urge the gripping element 48 against the seat 50 and 
thereby deform the gripping element 48. FIG. 2 best shows that the cap 54 
includes an annular cap flange 60 that is manually grippable by a person, 
for manipulating the cap 54. 
Briefly cross-referencing FIGS. 3 and 4, the gripping element 48 is biased 
to a normal configuration (FIG. 4) when the element 48 is not urged 
against the seat 50. In the normal configuration, the gripping element 48 
has an inside diameter ID.sub.1 which is sufficiently large to permit the 
surgical instrument 22 (not shown in FIG. 4) to slide within the 
instrument holder 30. 
On the other hand, when the gripping element 48 is urged against the seat 
50 by the cap 54 (FIG. 3), the gripping element 48 is deformed into a 
gripping configuration, wherein at least a portion of the gripping element 
48 has an inside diameter ID.sub.2 that is sufficiently small to prevent 
motion of the surgical instrument 22 within the instrument holder 30. 
In other words, when the gripping element 48 is in the gripping 
configuration, the gripping element 48 grips the surgical instrument 22 
and holds it stationary with respect to the instrument holder 30. Thus, 
the inside diameter ID.sub.1 of the gripping element 48 when in the normal 
configuration is greater than the inside diameter ID.sub.2 of the gripping 
element 48 when in the gripping configuration. 
Referring back to FIGS. 2 and 3, the advancer 10 includes an annular 
adjustment handle 62. As shown, the outside surface of the handle 62 is 
knurled or textured to facilitate manipulation of the handle 62 by a 
person. Also, the inside surface of the handle 62 is threaded, and the 
inside surface of the handle 62 is threadably engaged with the threaded 
portion 36 of the instrument holder 30. 
FIGS. 2 and 3 show that the handle 62 is formed with a lip 64 that 
protrudes radially inwardly. A retainer ring 66 is threadably engaged with 
the adaptor 12, and the lip 64 of the handle 62 is positioned between the 
retainer ring 66 and the flange 28 of the adaptor 12. Accordingly, the 
handle 62 can be rotated relative to the adaptor 12, but cannot move 
axially relative to the adaptor 12. 
As stated above, the hollow or annular components described above are 
coaxial, and together establish a passageway in which the surgical 
instrument 22 (FIGS. 1 and 3) can be positioned. It may now be appreciated 
that the gripping element 48 can be deformed to grip the surgical 
instrument 22, and the handle 62 rotated to move the instrument holder 30 
from a first position (FIG. 3) to a second position (FIG. 4) relative to 
the adaptor 12. Stated differently, the handle 62 can be rotated to move 
the advancer 10 from a shortened configuration (FIG. 3) toward an extended 
configuration (FIG. 4) to thereby advance the surgical instrument 22 into 
a patient, without manipulating the arm 18 of the surgical apparatus 16. 
FIG. 4 shows the dimensions of one presently preferred embodiment of the 
advancer 10. As shown, the cap 54 has a diameter 68 of about an inch 
(1.0"), and the advancer 10 has an overall length 70 of about three and 
six-tenths inches (3.6") when in the extended configuration. Also, the 
handle 62 has a length 72 of about one and three-tenths inches (1.3"), and 
the adaptor skirt 26 has an outside diameter 74 of about six hundred 
ninety-five thousandths of an inch (0.695"). 
FIG. 5 shows an alternate embodiment of the advancer of the present 
invention, generally designated 100. The advancer 100 is in all essential 
respects identical to the advancer 10, with the exceptions shown in the 
drawings and noted below. Specifically, the advancer 100 has a surgical 
instrument holder 102 that has an outside diameter 104 of about thirty 
five hundredths of an inch (0.35"). Also, the advancer 100 has an adaptor 
106 which has an outside diameter 108 of about fifty hundredths of an inch 
(0.50"). 
Furthermore, the advancer 100 includes a handle 110 having a length 112 of 
about one and two-tenths inches (1.2") and an outside diameter 114 of 
about eighty-eight hundredths of an inch (0.88"). As shown, the advancer 
100 also has a cap 116 for compressing a gripping element 118, and the cap 
116 can slide within the handle 110. Like the hollow components of the 
advancer 10, the hollow components of the advancer 100 share a common axis 
120. 
While the particular advancer for surgical instrument as herein shown and 
described in detail is fully capable of attaining the above-described 
objects of the invention, it is to be understood that it is the presently 
preferred embodiment of the present invention and is thus representative 
of the subject matter which is broadly contemplated by the present 
invention, that the scope of the present invention fully encompasses other 
embodiments which may become obvious to those skilled in the art, and that 
the scope of the present invention is accordingly to be limited by nothing 
other than the appended claims.