U.S. patent application number 11/701769 was filed with the patent office on 2008-08-07 for capsule medical apparatus and body-cavity observation method.
This patent application is currently assigned to Olympus Medical Systems Corporation. Invention is credited to Hidetake Segawa, Hironobu Takizawa.
Application Number | 20080188710 11/701769 |
Document ID | / |
Family ID | 39386103 |
Filed Date | 2008-08-07 |
United States Patent
Application |
20080188710 |
Kind Code |
A1 |
Segawa; Hidetake ; et
al. |
August 7, 2008 |
Capsule medical apparatus and body-cavity observation method
Abstract
Provided is a capsule medical apparatus including a capsule
body, a control member, and an observing member. The capsule body
is to be introduced into a lumen of a subject. The control member
controls a movement of the capsule body in the lumen by a flow of a
fluid introduced in the lumen. The observing member is fixed inside
the capsule body and observes a direction of the flow of the fluid
and a direction different from the flow of the fluid according to
the movement of the capsule body.
Inventors: |
Segawa; Hidetake; (Tokyo,
JP) ; Takizawa; Hironobu; (Tokyo, JP) |
Correspondence
Address: |
SCULLY SCOTT MURPHY & PRESSER, PC
400 GARDEN CITY PLAZA, SUITE 300
GARDEN CITY
NY
11530
US
|
Assignee: |
Olympus Medical Systems
Corporation
Tokyo
JP
|
Family ID: |
39386103 |
Appl. No.: |
11/701769 |
Filed: |
February 2, 2007 |
Current U.S.
Class: |
600/101 |
Current CPC
Class: |
A61B 1/00177 20130101;
A61B 1/045 20130101; A61B 1/00179 20130101; A61B 1/00156 20130101;
A61B 1/041 20130101; A61B 1/00181 20130101 |
Class at
Publication: |
600/101 |
International
Class: |
A61B 1/00 20060101
A61B001/00 |
Claims
1. A capsule medical apparatus comprising: a capsule body to be
introduced into a lumen of a subject; a control member controlling
a movement of the capsule body in the lumen by a flow of a fluid
introduced in the lumen; and an observing member fixed inside the
capsule body and observing a direction of the flow of the fluid and
a direction different from the flow of the fluid according to the
movement of the capsule body.
2. The capsule medical apparatus according to claim 1, wherein the
control member is a rotary guide member which rotates the capsule
body by the flow of the fluid in a circumferential direction about
a longitudinal axis of the capsule body.
3. The capsule medical apparatus according to claim 2, wherein the
rotary guide member includes a spiral member provided on an outer
surface of the capsule body so as to interfere the flow of the
fluid.
4. The capsule medical apparatus according to claim 3, wherein the
spiral member is a spirally-formed projection.
5. The capsule medical apparatus according to claim 4, wherein the
spirally-formed projection is a single continuous projection.
6. The capsule medical apparatus according to claim 4, wherein the
spirally-formed projection includes a plurality of discontinuous
projections.
7. The capsule medical apparatus according to claim 1, wherein the
observing member includes a first imaging member forming an imaging
field in a longitudinal direction of the capsule body and a second
imaging member forming an imaging field in a direction different
from the direction of the imaging field of the first imaging
member.
8. The capsule medical apparatus according to claim 7, wherein the
first imaging member has a far focus and the second observing
member has a near focus.
9. The capsule medical apparatus according to claim 7, wherein the
second observing member has the imaging field oblique to the
longitudinal axial direction of the capsule body.
10. The capsule medical apparatus according to claim 7, wherein the
second imaging member has the imaging field perpendicular to the
longitudinal axial direction in the capsule body.
11. The capsule medical apparatus according to claim 1, wherein the
control member is a rotary guide member which rotates the capsule
body in a radial direction about an axis passing through the
gravity center of the capsule body and perpendicular to the
longitudinal axis by the flow of the fluid.
12. The capsule medical apparatus according to claim 11, wherein
the rotary guide member includes a pair of one-way resistive
elements, the resistive elements having a same shape and being
located on an outer surface of the capsule body to be point
symmetric with respect to the gravity center of the capsule body,
and the resistive elements having directionality for generating a
reaction force toward the flow of the fluid.
13. The capsule medical apparatus according to claim 12, wherein
the one-way resistive elements are projections.
14. The capsule medical apparatus according to claim 13, wherein
the projections can be projected and retracted with respect to the
outer surface of the capsule body.
15. The capsule medical apparatus according to claim 13, wherein
the projections are pocket projections each having an opening
opened along the longitudinal axial direction.
16. The capsule medical apparatus according to claim 12, wherein
each of the one-way resistive elements is a groove opened toward an
end portion of the capsule body along the longitudinal axial
direction.
17. The capsule medical apparatus according to claim 12, wherein
each of the one-way resistive elements is a hole opened toward an
end portion of the capsule body along the longitudinal axial
direction.
18. The capsule medical apparatus according to claim 11, wherein
the observing member includes an imaging member which forms an
imaging field in the longitudinal axial direction of the capsule
body.
19. The capsule medical apparatus according to claim 11, wherein
the observing member includes two imaging members each being
respectively fixed at both end portions of the capsule body in the
longitudinal axial direction.
20. The capsule medical apparatus according to claim 19, wherein
the imaging members are a first imaging member and a second imaging
member, respectively the first imaging member being fixed at an end
of the capsule body in the longitudinal axial direction and having
a far focus, and the second imaging member being fixed at another
end of the capsule body in the longitudinal axial direction and
having a near focus.
21. The capsule medical apparatus according to claim 1, wherein the
capsule body has a specific gravity which is substantially one with
respect to the fluid introduced into the subject, and the gravity
center of the capsule body is in a substantial center of the
capsule body.
22. A body-cavity observation method, comprising the steps of:
ingesting a capsule medical apparatus; ingesting a fluid having a
specific gravity which is substantially same as that of the capsule
medical apparatus; controlling the capsule medical apparatus
movement in a lumen, by a flow of the fluid; observing, by the
capsule medical apparatus, a direction of the flow of the fluid;
and observing, by the capsule medical apparatus, a direction
different from the direction of the flow of the fluid.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a capsule medical apparatus
such as a capsule endoscope for traveling in a lumen with a liquid
such as water, which is introduced into a subject, to observe
inside the lumen and a body-cavity observation method.
[0003] 2. Description of the Related Art
[0004] Recently, in a field of endoscopes, a capsule endoscope
having an imaging function and a radio communication function has
been appearing. This capsule endoscope includes a structure for
displacing along with peristaltic movement in an internal organ (in
a lumen) such as the esophagus, stomach and small intestine and
sequentially taking images with its imaging function until it is
naturally discharged from the body of the subject, after swallowed
by the subject through his or her mouth for the observation
(examination).
[0005] WO 02/95351 discloses a technique suited for observing the
large intestine, in which the specific gravity of the capsule
endoscope is set as same as that of the liquid therearound or 1
which is same as that of water so that, when a subject swallows the
capsule endoscope with the liquid, the capsule endoscope floats in
the liquid and travels quickly in the body-cavity to the large
intestine. When the capsule endoscope is attached to the wall
surface of the body-cavity, only close narrow area is imaged;
however, according to WO 02/95351, since the capsule endoscope
floats in the liquid to observe, an observing field is maintained
and every part can be observed.
[0006] Regarding observations of inside hollow organs such as the
large intestine with the use of such a capsule endoscope, an entire
of the lumen may be needed to be observed in some cases and a
particular portion such as a polyp (lumen wall) may be needed to be
observed in other cases. In order to meet such demands, for
example, WO 03/11103 discloses a capsule endoscope having at least
one illumination source, at least one imaging sensor, and at least
two optic systems. Further, WO 02/54932 discloses a capsule
endoscope having at least one imaging device and an optic system
including a plurality of optical paths. According to WO 03/11103
and WO 02/54932, the capsule endoscope is capable of imaging the
lumen not only in the axial direction of the lumen but also in an
inner wall direction of the lumen in the hollow organ.
[0007] However, according to the capsule endoscope of WO 03/11103
and WO 02/54932, the system depends on the structure of the imaging
optical system in the capsule endoscope and in order to optimize
imaging direction to perform a proper observation in the lumen in
its axial direction and the inner wall direction, more optic
systems or optical paths are required to be set. Thus, the
structure becomes more complex and enlarged so that the proper size
of the capsule endoscope to be introduced into a subject cannot be
maintained.
SUMMARY OF THE INVENTION
[0008] A capsule medical apparatus according to one aspect of the
present invention includes a capsule body to be introduced into a
lumen of a subject; a control member controlling a movement of the
capsule body in the lumen by a flow of a fluid introduced in the
lumen; and an observing member fixed inside the capsule body and
observing a direction of the flow of the fluid and a direction
different from the flow of the fluid according to the movement of
the capsule body.
[0009] A body-cavity observation method according to another aspect
of the present invention includes the steps of: ingesting a capsule
medical apparatus; ingesting a fluid having a specific gravity
which is substantially same as that of the capsule medical
apparatus; controlling, by the capsule medical apparatus, movement
in a lumen by a flow of the fluid; observing, by the capsule
medical apparatus, a direction of the flow of the fluid; and
observing, by the capsule medical apparatus, a direction different
from the direction of the flow of the fluid.
[0010] The above and other objects, features, advantages and
technical and industrial significance of this invention will be
better understood by reading the following detailed description of
presently preferred embodiments of the invention, when considered
in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic block diagram showing a use example of
a capsule endoscope according to a first embodiment of the present
invention;
[0012] FIG. 2 is a schematic block diagram showing a use example of
a capsule endoscope according to a first modification;
[0013] FIG. 3 is a schematic block diagram showing a use example of
a capsule endoscope according to a second modification;
[0014] FIG. 4 is a schematic rear view of the capsule
endoscope;
[0015] FIG. 5 is a schematic perspective view showing the capsule
endoscope according to a second embodiment of the present
invention;
[0016] FIG. 6 is a rear view of the capsule endoscope in FIG.
5;
[0017] FIGS. 7A, 7B and 7C are schematic block diagrams showing a
use example of the capsule endoscope;
[0018] FIG. 8 is a schematic block diagram showing a use example of
a capsule endoscope according to a third modification;
[0019] FIG. 9 is a schematic block diagram showing a use example of
a capsule endoscope according to a fourth modification;
[0020] FIG. 10 is a schematic block diagram showing a use example
of a capsule endoscope according to a fifth modification;
[0021] FIG. 11 is a rear view of the capsule endoscope in FIG.
10;
[0022] FIG. 12 is a schematic block diagram showing a use example
of a capsule endoscope according to a sixth modification;
[0023] FIG. 13 is a rear view of the capsule endoscope in FIG. 12;
and
[0024] FIGS. 14A, 14B and 14C are schematic block diagrams showing
a use example of a capsule endoscope according to a seventh
modification.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] Embodiments of a capsule medical apparatus and a body-cavity
observation method according to the present invention will be
described with reference to the drawings. The embodiments describe
examples of the present invention applied to a capsule endoscope as
a capsule medical apparatus. It will be appreciated that the
present invention is not limited to the following embodiments and
can be implemented with modifications within the spirit of the
present invention.
[0026] FIG. 1 is a schematic block diagram showing a use example of
a capsule endoscope according to a first embodiment of the present
invention. The capsule endoscope 10 of the first embodiment
includes a capsule body 20 insertable into a lumen of a subject 1
to be tested, an observing member 30 installed in the capsule body
20, other installed elements such as a radio transmission unit, a
battery, an image processing unit, which are not shown, and a
rotary guide member 40 disposed on outer face of the capsule body
20.
[0027] The capsule body 20 is made in a size capable of being
swallowed by the subject 1 through his or her mouth into a body
cavity of the subject 1. The capsule body 20 is formed in a domed
capsule shape, in which ends of hemispherical domes are integrated
by a cylindrical member therebetween and the direction connecting
the ends of the hemispherical domes represents a longitudinal
direction.
[0028] Here, the capsule endoscope 10 of the first embodiment is
configured to propel in the lumen 2 of the subject 1, for example,
the large intestine, as floating in a fluid 3 that is introduced in
the lumen 2. The capsule body 20, which includes installed elements
such as the observing member 30, is configured to have a specific
gravity that is substantially one with respect to the fluid 3,
substantially the same as the fluid 3. The fluid 3 is a fluid,
which is capable of being swallowed by the subject 1 through his or
her mouth and is clear to the wavelength of a light source used by
the observing member 30 for imaging. In the first embodiment,
drinkable water having specific gravity close to one is used as an
example of the fluid 3. A gravity center G of the capsule body 20
containing the observing member 30 and other elements is set as the
center of the capsule body 20 (the center on the longitudinal axis
L passing through the center of the cylinder).
[0029] Further, the observing member 30 is an imaging member for
imaging an image of the inside of the lumen and, according to the
fist embodiment, is composed of fist and second imaging members 31,
32 which are fixed at a position one-sided with respect to the
longitudinal axial direction in the capsule body 20. The first
imaging member 31, which is not shown, includes a light source for
illuminating an imaging region, a solid-state imaging device such
as CCD or CMOS imager for receiving catoptric light from the
imaging region generated by the illuminating light of the light
source to image the inside of the lumen, and an imaging optic
system such as an imaging lens for producing an optical image of
the imaging region to the solid-state imaging device. As shown with
dashed lines in FIG. 1, the first imaging member 31 is disposed so
as to provide an imaging field in the longitudinal axial direction
of the capsule body 20. Further, the second imaging member 32,
which is not shown, includes a light source for illuminating an
imaging region, a solid-state imaging device such as CCD or CMOS
imager for receiving catoptric light from the imaging region
generated by the illuminating light of the light source to image
the inside of the lumen, and an imaging optic system such as an
imaging lens for producing an optical image of the imaging region
to the solid-state imaging device. As shown with the dashed lines
in FIG. 1, the second imaging member 32 is disposed so as to
provide an imaging field in a direction oblique to the longitudinal
axis direction of the capsule body 20. Here, the first imaging
member 31 is set to be a far focus to focus on a distant point and
the second imaging member 32 is set to be a near focus to focus on
a close point. The imaging field of the second imaging member 32
may be in a horizontal direction with respect to the vertical axial
direction of the capsule body 20. Here, the capsule body 20
includes a member having clearness or translucency at least at
regions corresponding to the imaging fields of the first and second
imaging members 31, 32.
[0030] Further, the rotary guide member 40 is configured to work as
a control member for controlling movement of the capsule body 20 in
the lumen 2, which is moved by the flow of the fluid 3 introduced
into the lumen 2. According to the first embodiment, the rotary
guide member 40 is configured to rotate the capsule body 20 with
the flow of the fluid 3 about the longitudinal axis of the capsule
body 20 in a circumferential direction. The rotary guide member 40
is composed of a spiral member formed of a continuous projection 41
with projection amount which is capable of interfering the flow of
the fluid 3, spirally formed around the outer surface of the
capsule body 20. The cross-sectional shape of the projection 41 may
be formed in a hemicycle or a rectangle shape. Further, the
interval of the spiral, the number of the spiral, the angle of the
spiral or the like of the projection 41 can be set arbitrarily.
[0031] An image processing unit which is installed in the capsule
body 20, which is not shown, provides necessary processing on the
images of the inside of the lumen taken by the first and second
imaging members 31, 32. A radio transmission unit, which is not
shown, radio-outputs lumen image data which has been subjected to
necessary processing by the image processing unit to a receiver
(not shown) or the like disposed outside the subject 1. A battery,
which is not shown, supplies necessary power to an electrical drive
unit such as the light source or solid-state imaging device in the
capsule body 20.
[0032] Next, an observation of inside of the lumen 2, for example,
the large intestine, with the use of the capsule endoscope 10 of
the first embodiment will be described. Basically, the capsule
endoscope 10 and the fluid 3 are swallowed by the subject 1 to
substantially fill the lumen 2 such as the large intestine as an
observed portion in the subject 1 with the fluid 3 so that the
capsule endoscope 10 travels as floating in the fluid 3. Then the
inside image of the lumen is taken by the first and second imaging
members 31, 32 to observe the lumen. The capsule endoscope 10 and
the liquid 3 may be swallowed at the same time or may be swallowed
in any order.
[0033] Here, as shown by arrows in FIG. 1, the fluid 3 introduced
in the lumen 2 flows along the axis of the lumen 2 toward an exit
of the lumen. When the capsule endoscope 10 is in such a flow of
the fluid 3, since the capsule body 20 has the rotary guide member
40 of the spirally formed projection 41 on the outer face and the
rotary guide member 40 interferes the flow of the fluid 3, the
capsule endoscope 10 is controlled to move along the flow as
rotating in the circumferential direction about the longitudinal
axis L. The first and second imaging members 31, 32 take images
inside the lumen 2 in such movements of the capsule body 20. In
other words, the first imaging member 31 takes images of the lumen
2, as rotating, in front (or back) in the axial direction that is
the direction of the flow of the fluid 3. The second imaging member
32 sequentially takes images of an internal surface 2a of the lumen
2, which is located in different direction from the flow of the
fluid 3, as moving around therein. Further, since the focus
position of the first imaging member 31, which images the lumen 2
in the axial direction, is set at a long distance, a far focused
and fine image of the inside of the entire lumen can be obtained.
Since the focus position of the second imaging member 32, which
images the internal surface 2a as moving around therein, is set at
a short distance, a near focused and fine internal surface image
can be obtained and a particular portion such as a polyp 2b can
surely be observed.
[0034] As described above, according to the capsule endoscope 10 of
the first embodiment, the observing fields in the lumen 2 can be
dynamically changed to be optimized by controlling the capsule body
20 to move as rotating in a circumferential direction with the use
of the flow of the fluid 3. With this structure, the entire parts
in the lumen 2 can surely be observed without complicating the
structure of an observing member (imaging member), which is to be
installed in the capsule body 20. Further, according to the capsule
endoscope 10 of the first embodiment, the gravity center G is set
at the substantially center of the capsule body 20 and the specific
gravity with respect to the fluid 3 is set as substantially one.
Accordingly, the capsule body 20 is in a mobile state and rotatable
smoothly in the circumferential direction when the rotary guide
member 40 interferes the flow of the fluid 3. With this structure,
the above described observing operation can be certainly
performed.
[0035] FIG. 2 is a schematic block diagram showing a use example of
the capsule endoscope according to a first modification. According
to a capsule endoscope 11 of the first modification, a rotary guide
member 42 is formed with a plurality of noncontiguous projections
43 so as to form an intermissive spiral shape. In this way, the
rotary guide member 42 may be formed in an intermissive spiral
shape with the noncontiguous projections 43 if the rotary guide
member 42 is configured to interface the flow of the fluid 3 to
rotate the capsule body 20 in a circumferential direction about the
longitudinal axis L. Such a rotary guide member 42 may be formed
more easily than the rotary guide member of the continuous
projection 41.
[0036] The rotary guide member is not limited to what is formed
spirally with the projections 41, 43 and may be, for example,
formed with a recess, which is spirally formed on the outer surface
of the capsule body 20 to interface the flow of the fluid 3.
Further, according to the first embodiment and the first
modification, the observing member 30 (the first and second imaging
members 31, 32) is not limited to be disposed only at one end in
the capsule body 20 and the observing members 30 may be fixed at
both ends as a compound-eye-type structure. In addition, the first
imaging member 31 and the second imaging member 32 may be arranged
at different ends.
[0037] FIG. 3 is a schematic block diagram showing a use example of
a capsule endoscope according to a second modification and FIG. 4
is a schematic rear view of the capsule endoscope. A capsule
endoscope 12 according to the second modification includes a
propeller 44 as a rotary guide member 45, which is integrally
provided on the outer surface of a rear portion (the portion where
the observing member 30 is not provided) of the capsule body 20.
When the capsule endoscope 12 having such structure receives a flow
of the fluid 3 in the lumen 2, the propeller 44 as the rotary guide
member 45 rotates as interfering the flow of the fluid 3 so that
the capsule body 20 moves forward in the lumen 2 as rotating,
together with the propeller 44, in a circumferential direction
about the longitudinal axis L. Accordingly, same as the case of the
first embodiment, the inside of the lumen 2 may surely be
observed.
[0038] Next, a capsule endoscope according to a second embodiment
of the present invention will be described. FIG. 5 is a schematic
perspective view showing the capsule endoscope according to the
second embodiment, FIG. 6 is a rear view of the capsule endoscope
in FIG. 5, and FIGS. 7A, 7B and 7C are schematic block diagrams
showing a use example of the capsule endoscope. A capsule endoscope
50 according to the second embodiment includes a capsule body 60
which is insertable into a lumen of a subject 1, an observing
member 70 installed in the capsule body 60, other installed
elements, which are not shown, such as a radio transmission unit, a
battery or an image processing unit, and a rotary guide member 80
disposed on the outer surface of the capsule body 70.
[0039] The capsule body 60 is basically same as the capsule body
20. The capsule body 60 is made in a size capable of being
swallowed by the subject 1 through his or her mouth into a cavity.
The capsule body 60 is formed in a domed capsule shape, in which
ends of hemispherical domes are integrated by a cylindrical member
therebetween and the direction connecting the ends of the
hemispherical domes is a longitudinal direction.
[0040] Here, the capsule endoscope 50 of the second embodiment
moves in a lumen 2, for example, the large intestine of the subject
1, as floating in the fluid 3 introduced into the lumen 2. The
capsule body 60, which includes elements such as the observing
member 70 therein, is configured to have a specific gravity that is
substantially one with respect to the fluid 3, substantially the
same as that of the fluid 3. The fluid 3 is a liquid, which is
capable of being swallowed by the subject 1 through his or her
mouth and is clear to the wavelength of a light source used by the
observing member 30 for imaging. In the second embodiment,
drinkable water having specific gravity close to one is used as an
example of the fluid 3. The gravity center G of the capsule body 60
containing the observing member 30 and other elements is set as the
center of the capsule body 60 (the center on the longitudinal axis
L passing through the center of the cylinder).
[0041] Further, the observing member 70 is an imaging member for
imaging an image of the inside of the lumen and, according to the
second embodiment, is composed of an imaging member 71 that is
fixed at a position one-sided with respect to the longitudinal
axial direction in the capsule body 60. The imaging member 71,
which is not shown, includes a light source for illuminating an
imaging region, a solid-state imaging device such as CCD or CMOS
imager for receiving catoptric light from the imaging region
generated by the illuminating light of the light source to image
the inside of the lumen, and an imaging optical system such as an
imaging lens for producing an optical image of the imaging region
to the solid-state imaging device. As shown with dashed lines in
FIGS. 7A to 7C, the imaging member 71 is disposed so as to provide
an imaging field in the longitudinal axial direction of the capsule
body 60. Here, the capsule body 60 includes a member having
clearness or translucency at least at regions corresponding to the
imaging field of the imaging member 71.
[0042] Further, the rotary guide member 80 is configured to work as
a control member for controlling movement of the capsule body 20 in
the lumen 2, which is moved by the flow of the fluid 3 introduced
into the lumen 2. According to the second embodiment, the rotary
guide member 80 is configured to rotate the capsule body 60 with
the flow of the fluid 3 about an axis S passing through the gravity
center G of the capsule body 60 and substantially perpendicular to
the longitudinal axis L in a circumferential direction. The rotary
guide member 80 is composed of projections 81, 82 in a pocket form
having openings 81a, 82a on the outer surface of the capsule body
60 to form a pair of one-way resistive elements. The openings 81a,
82a are opened along the longitudinal axial direction and toward
the center portion of the capsule body 60. These pocket projections
81, 82 are disposed at a position off the center of the
longitudinal axis L on the outer surface of the capsule body 60 so
as to be point symmetric with respect to the gravity center G of
the capsule body 60. Further, these pocket projections 81, 82 are
formed symmetrically when they are divided into two pieces at a
plane face including the longitudinal axis L of the capsule body 60
and disposed to be point symmetric with respect to the gravity
center G of the capsule body 60. Here, the pocket projections 81,
82 work as resistive elements and generate reaction force when the
openings 81a, 82a are opened toward upstream to face to the flow of
the fluid 3, and, on the other hand, the pocket projections 81, 82
do not work as resistive elements when the openings 81a, 82a are
opened toward downstream and does not face to the flow of the fluid
3 and have directionality to generate reaction force to the flow of
the fluid 3.
[0043] Next, an observation of inside of the lumen 2, for example,
the large intestine with the use of the capsule endoscope 50 of the
second embodiment will be described. Basically, the capsule
endoscope 50 and the fluid 3 are swallowed from a mouth to
substantially fill the lumen 2 such as the large intestine as an
observed portion in the subject 1 with the fluid 3 so that the
capsule endoscope 50 travels as floating in the fluid 3 while an
imaging member 71 takes images of the inside of the lumen 2. The
capsule endoscope 50 and the liquid 3 may be swallowed at the same
time or may be swallowed in any order.
[0044] Here, as shown by arrows in FIG. 7A, the fluid 3 introduced
in the lumen 2 flows toward an exit of the lumen. When the capsule
endoscope 50 is in such a flow of the fluid 3, since the capsule
body 60 has the rotary guide member 80 of the pocket projections
81, 82 on its outer face, one of the projection 81 or the
projection 82 faces to the flow of the fluid 3 to generate a
reaction force. Accordingly, the capsule body 60 is controlled to
move along the flow as rotating radially about an axis S that
passes through the gravity center G of the capsule body 60 and
substantially perpendicular to the longitudinal axis L.
[0045] For example, as shown in FIG. 7A, when the opening 81a of
the projection 81 faces to the flow of the fluid 3, the projection
81 generates an reaction force against the flow of the fluid 3 and
works as a trigger to rotate the capsule body 60 in the clockwise
direction about the axis S. The capsule body 60 rotates in the
clockwise direction about the axis S (rolls forward) along the flow
of the fluid 3, as shown in FIG. 7B. In this operation, the other
projection 82 does not generate a reaction force since the opening
82a does not face to the flow. Then, when the capsule body 60
continues to rotate, as shown in FIG. 70C, the opening 82a of the
other projection 82 comes to face to the flow of the fluid 3 and
the projection 82 generates a reaction force against the flow of
the fluid 3 to rotate the capsule body 60 in the clockwise
direction about the axis S. With repeating this operation, the
capsule body 60 travels forwardly in the lumen 2 as rotating about
the axis S by the flow of the fluid 3.
[0046] The imaging member 71 takes images of the inside of the
lumen 2 in such a movement of the capsule body 60. In other words,
the imaging member 71 sequentially takes images of internal
surfaces 2a of the lumen 2 at front side and back side of an axis
of the lumen 2 that is the flowing direction of the fluid 3 and at
different directions from the flowing direction of the fluid 3 as
rotating forwardly and following the rotating trajectory. With this
structure, the entire area in the lumen 2 and particular parts of
the internal surface 2a can be observed.
[0047] When the flow of the fluid 3 is small, since the resistance
received by the projection 81 or 82 facing to the flow becomes
small, the capsule body 60 does not rotate about the axis S.
Accordingly, when the flow is small, the imaging member 71 takes
images in axial direction of the lumen 2 and, when the flow has
certain strength or more, the imaging member 71 observes particular
portion of the internal surface 2a. When the flow of the fluid 3
has a periodicity, both entire images and partial images can be
observed more efficiently.
[0048] As described above, according to the capsule endoscope 50 of
the second embodiment, the capsule body 60 is moved as rotating
radially about the axis S (rotating forwardly) with the use of the
flow of the fluid 3. With this structure, an observing field in the
lumen 2 can dynamically be changed to be optimized even when the
capsule endoscope 50 has a structure including a single observing
member 70 for a direct view. Thus, the entire area in the lumen 2
can be surely observed without complicating the structure of an
observing member (imaging member), which is to be installed in the
capsule body 60. Further, according to the capsule endoscope 50 of
the second embodiment, the gravity center G is set at the
substantially center of the capsule body 60 and the specific
gravity with respect to the fluid 3 is set as substantially one.
Accordingly, the capsule body 60 is in a mobile state and rotatable
in the radial direction about the axis S smoothly when the pocket
projections 81, 82 constituting the rotary guide member 80
alternately face to the flow of the fluid 3. With this structure,
the above described observing operation can certainly be
performed.
[0049] FIG. 8 is a schematic block diagram showing a use example of
a capsule endoscope according to a third modification. A capsule
endoscope 51 of the third modification has a pair of pocket
projections 81, 82 constituting a rotary guide member 80 in which
openings 81a, 82a are opened toward ends along the longitudinal
axial direction. With the capsule endoscope 51 having the structure
described in the third modification, operations and effects same as
those of the second embodiment can be obtained.
[0050] FIG. 9 is a schematic block diagram showing a use example of
a capsule endoscope according to a fourth modification. A capsule
endoscope 52 of the fourth modification includes an imaging member
71 as a first observing member and a second observing member 72 for
forming at another imaging field in a longitudinal direction of the
capsule body 60, which is fixed another end of the capsule body 60.
A compound-eye-type observing member 70 is composed of the first
and second imaging members 71, 72.
[0051] Here, similarly to the first imaging member 71, the second
observing member 72, which is not shown, includes a light source
for illuminating an imaging region, a solid-state imaging device
such as CCD or CMOS imager for receiving catoptric light from the
imaging region generated by the illuminating light of the light
source to image the inside of the lumen, and an imaging optical
system such as an imaging lens for producing an optical image of
the imaging region to the solid-state imaging device. Further, the
first imaging member 71 is set to be a far focus to focus on a
entire image of the lumen 2 and the second imaging member 72 is set
to be a near focus to observe the internal surface or the like of
the lumen 2. Here, the capsule body 60 also includes a member
having clearness or translucency for a region corresponding to the
imaging field of the second imaging member 72.
[0052] With the capsule endoscope 52 having the structure described
in the fourth modification, operations and effects same as those of
the second embodiment can be obtained. Particularly, since the
capsule endoscope 52 of the third modification has a
compound-eye-type structure with the first and second imaging
members 71, 72 having different focusing lengths, when the capsule
body 60 rotates radially about the axis S by the flow of the fluid
3, the first and second imaging members 71, 72 sequentially take
images in the lumen 2 as following the rotating trajectory. In this
case, since the focus position of the first imaging member 71 is
set at a long distance, a far focused and fine image of the inside
of the entire lumen can be obtained by extracting a well-focused
image from the obtained images. Further, since the focus position
of the second imaging member 72 is set at a short distance, a near
focused and fine internal surface image can be obtained and a
particular portion such as a polyp can surely be observed by
extracting a well-focused image from the obtained images.
[0053] FIG. 10 is a schematic block diagram showing a use example
of a capsule endoscope according to a fifth modification and FIG.
11 is a rear view of the capsule endoscope. A capsule endoscope 53
of the fifth modification includes a pair of grooves 83, 84 as a
pair of one-way resistive elements constituting a rotary guide
member 80, as substitutes for the pair of pocket projections 81,
82. The grooves 83, 84 are formed in a manner being opened near the
end portions on the outer surface of the capsule body 60 along the
longitudinal axial direction and toward the side of the end
portions. Inner walls of the grooves 83, 84 work as fluid contact
faces 83a, 84b. The grooves 83, 84 are arranged to be point
symmetric with respect to the gravity center G of the capsule body
60. Further, the cross-sectional shape of the grooves 83, 84 may be
triangular or U-shaped which are symmetrical when they are divided
into two at a flat face including the longitudinal axis L of the
capsule body 60 and arranged to be point symmetric with respect to
the gravity center G.
[0054] Here, the grooves 83, 84 work as resistive elements to
generate a reaction force when the fluid contact faces 83a, 84a
face toward the upstream and face to the flow of the fluid 3, and
the grooves 83, 84 do not work as resistive element when the fluid
contact face 83a, 84a face toward the downstream and do not face to
the flow of the fluid 3 and have directionality to generate
reaction force to the flow of the fluid 3. With the capsule
endoscope 53 having the structure described in the fifth
modification, operations and effects same as those of the second
embodiment can be obtained.
[0055] FIG. 12 is a schematic block diagram showing a use example
of a capsule endoscope according to a sixth modification and FIG.
13 is a rear view of the capsule endoscope. A capsule endoscope 54
of the sixth modification includes a pair of holes 85, 86 as a pair
of one-way resistive elements constituting a rotary guide member
80, as substitutes for the pair of pocket projections 81, 82. The
holes 85, 86 are formed in a manner opened near the end portions on
the outer surface of the capsule body 60 along the longitudinal
axial direction and toward the side of the end portions. The holes.
85, 86 are arranged to be point symmetric with respect to the
gravity center G of the capsule body 60. Further, the
cross-sectional shape of the holes 85, 86 may be triangular or
round shape, which are symmetrical when they are divided into two
at a flat face including the longitudinal axis L of the capsule
body 60, and arranged to be point symmetric with respect to the
gravity center G.
[0056] Here, the holes 85, 86 work as resistive elements to
generate a reaction force when the openings opened toward the
upstream and face to the flow of the fluid 3, and the holes 85, 86
do not work as resistive element when the openings open toward the
downstream and do not face to the flow of the fluid 3 and have
directionality to generate reaction force to the flow of the fluid
3. With the capsule endoscope 54 having the structure described in
the sixth modification, operations and effects same as those of the
second embodiment can be obtained.
[0057] Here, according to the third to sixth modifications of the
second embodiment, the rotary guide member 80 is composed of a pair
of one-way resistive elements formed by the pair of the pocket
projections 81, 82, grooves 83, 84, or holes 85, 86. However, the
rotary guide member 80 composed of a pair of one-way resistive
elements in which a plurality of projections, grooves, or holes are
symmetrically disposed in combination in each side may be
employed.
[0058] Further, the projected resistive element may be openable and
closable (projected and retracted) with respect to the outer
surface of the capsule body. In other words, when the fluid 3 is
still (or its flow is small), the resistive element is closed
(installed in the capsule body) and when a large flow is generated,
the resistive element is opened (projected) corresponding to the
flow. With this structure, since projections are projected only
when they are need, the capsule endoscope can be easily swallowed
by the subject 1.
[0059] FIGS. 14A to 14C are schematic block diagrams showing a
capsule endoscope according to a seventh modification. A capsule
endoscope 55 of the seventh modification includes a weight 91
installed in the capsule body 60 and a slide space 92 for sliding
the position of the weight 91 in the longitudinal axial direction
of the capsule body 60. Here, the weight 91 slides in the slide
space 92 due to the flow of the fluid 3 to the capsule body 60 so
that the position of the gravity center of the capsule body 60 is
changed.
[0060] When the capsule endoscope 55 having such a structure is
introduced in the lumen 2 and stays in the fluid 3, for example,
the weight 91 is located at a position one-sided in the slide space
92, as shown in FIG. 14A, and the capsule endoscope 55 flows in the
fluid 3 in a manner of being tilted due to the position of the
gravity center, as shown in FIG. 14A. When the flow of the fluid 3
works on the capsule body 60 in such a condition, the capsule body
60 rotates forwardly to be a substantially horizontal state, as
shown in FIG. 14B. With such movement of the capsule body 60, the
weight 91 slides to the center of the slide space 92 and further
moves to the other end of the slide space 92. According to the
dynamical changes of the position of the gravity center, the
capsule body 60 moves to continue the rotation, as shown in FIG.
14C. By repeating this operation, the capsule body 60 travels in
the lumen 2 due to the flow of the fluid 3 as rotating forwardly.
Accordingly, with the capsule endoscope 55 having the structure
described in the seventh modification, operations and effects same
as those of the second embodiment can be obtained.
[0061] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *