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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a therapeutical apparatus of
extracorporeal type, and more particularly, to a therapeutical apparatus
of extracorporeal type in which an object to be treated (such as a
calculus formed within a physical body of a patient) is detected by a
measuring apparatus, and therapeutic shock wave energy which is generated
externally of the physical body is focussed upon the object to fracture
it, and specifically, to an ultrasonic therapeutical apparatus which
focuses an ultrasonic shock wave from a source located externally of the
physical body upon the object to be treated for the purpose of fracturing
the same.
2. Prior Art
An arrangement which utilizes an X-ray or ultrasonic measuring apparatus to
detect the presence of a calculus formed in a bile duct or kidney, and
which also utilizes therapeutical energy in the form of a shock wave which
is produced, as by voltage discharge or ultrasonic vibration, externally
of the physical body of a patient and is focussed upon the calculus to
fracture it, is disclosed in U.S. Pat. No. 4,617,931. As disclosed in this
patent, a probe with piezoelectric elements disposed in an array in a
mosaic pattern along a quadratic surface is brought into contact with a
patient's back via a water bag filled with an ultrasonic wave transmitting
medium such as water interposed therebetween to focus an ultrasonic shock
wave from the piezoelectric elements upon a calculus, as formed within a
kidney, to fracture it. As disclosed in Japanese Laid-Open patent
applications No. 31,140/1988 and No. 45,747/1986, an ultrasonic probe may
move across an extensive area and focus an ultrasonic wave of increased
intensity upon a calculus once it is located. Japanese Laid-Open patent
application No. 37,149/1986 discloses a measuring apparatus including a
detection system which determines positions in two directions. The present
applicant has also proposed an arrangement which permits displacement of
the ultrasonic probe in a direction perpendicular to the scan direction,
as disclosed in Japanese patent application No. 282,979/1986. U.S. Pat.
No. 4,526,168 discloses a technique for focussing an ultrasonic wave upon
a calculus by changing the timing and phases with which a plurality of
piezoelectric elements are driven. In the ultrasonic therapeutical
apparatus disclosed in U.S. Pat. No. 4,617,931, the ultrasonic probe is
located only at the center of an ultrasonic wave generator which provides
an ultrasonic wave of an increased intensity, resulting in a limited
scanning field over which an observation is possible. However, such an
arrangement may fail to locate a calculus. When displacement of the probe
in a direction perpendicular to the scan direction is enabled as disclosed
in Japanese patent application No. 282,979/1986, tracking the movement of
the calculus is possible, but it is still difficult to locate the calculus
before the therapy is conducted. A manual focussing operation results in a
low hit rate of the ultrasonic wave whenever the calculus happens to move
as a result of breathing.
The ultrasonic therapeutical apparatus disclosed in Japanese Laid-Open
patent application No. 31,140/1986 enables the extent of observation to be
increased, but involves a combination with a patient suspension system
with the patient suspended in a bath in a water vessel, thus
disadvantageously requiring a very bulky arrangement. The ultrasonic
therapeutical apparatus disclosed in Japanese Laid-Open patent application
No. 37,149/1986 uses X-ray in its detector, which may be hazardous to the
patient. In addition, where a pair of ultrasonic probes are employed, they
are located such that each scan plane passes through the focus of a
reflector of the shock wave and such that their axes are perpendicular to
each other. This limits the extent of observation which is available, and
thus still leaves much to be improved.
The apparatus disclosed in U.S. Pat. No. 4,617,931 includes means for
focussing a shock wave on a calculus. Specifically, an ultrasonic wave or
X-ray is employed to detect the spatial location of a calculus within the
physical body of a patient, as illustrated in FIG. 46, where the focal
point of the shock wave is indicated by a marker on an image 300 which is
obtained by ultrasonic or X-ray tomography. The positioning is achieved by
bringing an image 302 of a calculus into alignment with the marker. Thus,
the position of a focus F is indicated as shown at 304 on a display 303,
and the means for generating a shock wave is moved so that the image 302
of the calculus is aligned with the position of the focus F. However, such
technique only indicates the focal point of the display.
Accordingly, where organs such as lungs, intestines or bones, which are
sensitive to the shock wave, are located around the calculus when the
latter is to be fractured, there arises a significant problem inasmuch as
such organ may be damaged or otherwise adversely influenced by the shock
wave.
Another form of therapeutical apparatus of extracorporeal type is disclosed
in Japanese patent application No. 282,980/1986 (see FIGS. 44 and 45). The
apparatus includes ultrasonic measuring means 311 (location detecting
means) which detects the location of a calculus within the physical body,
positioning signal generating means 312, focus shifting means 313 and
shock wave generating means 314 which generates a shock wave used to
fracture a calculus.
The ultrasonic measuring means 311 includes an ultrasonic measuring unit
317 which radiates an ultrasonic wave toward a patient 315 to detect the
location of a calculus 316, and a display unit 318 which receives a
detection signal to indicate the location of the calculus on a CRT screen.
The positioning signal generating means 312 includes a single generator 320
which fixes a marker on a given point on the screen of the display unit
318 and produces a signal which is delivered to focus shifting means 313
which is effective to bring the focus of the fracturing shock wave into
alignment with the marker. The generator 320 is effective to process the
image of the detected calculus so that an operator (such as a surgeon) can
recognize the size or the number of calculus or calculi displayed and to
indicate a most effective signal on the screen as by a light pen to
indicate the sequence in which the calculi are to be fractured in order of
decreasing size, or to indicate a particular region of a coral calculus
where the fracture is to be initiated or to change the focal point of the
shock wave in response to the location and size of the calculus which is
performed periodically during the fracturing process because of a
displacement of the calculus. The generator stores such signals, and
delivers them to a drive unit 319 which shifts the shock wave generator
during the fracturing process.
The focus shifting means 319 or the drive unit which shifts the shock wave
generator operates to drive both a water bag 321 and a shock wave
generator 322 by means of a numerically controlled robot in accordance
with the positioning signal. The shock wave generator 322 includes a
plurality of ultrasonic vibrators or piezoelectric elements 323 which are
applied to and secured to the front surface of a mounting plate 324, which
is formed as a spherical surface, in a mosaic pattern. The front surface
of the piezoelectric elements which emit the shock wave is directed toward
the patient 315. The water bag 321 includes an ultrasonic wave
transmitting medium and means for injecting liquid medium and controlling
the pressure of the medium.
The water bag is interposed between the shock wave generator 322 and the
patient 315. The shock wave transmitting liquid (such as water) fills the
bag 321.
The shock wave generating means 314 includes a known ultrasonic pulse
voltage generator for driving the piezoelectric elements 323.
FIG. 45 indicates the sequence of operation performed by the apparatus
mentioned above. Initially, the location of the calculus within the
physical body of a patient is determined by the measuring means 311. The
positioning signal generating means 312 analyses the condition of the
calculus which is detected by the measuring means. An operator (such as a
surgeon) selects an optimum procedure to treat the calculus depending on
the kind thereof. In response thereto, a positioning signal (which
determines the sequence of treatment) is stored. The focus shifting means
313 is activated in accordance with the positioning signal to drive the
water bag 321 and the shock wave generator 322 so that the shock wave is
focussed upon the calculus. Subsequently, a shock wave is generated in
response to the shock wave generating means 314 to fracture the calculus.
After a given number of shock waves have been generated, the procedure is
temporarily stopped, and the size of the remaining calculus or the focal
point of the shock wave is determined again, and the above operation is
repeated until the calculus is completely fractured.
However, in the therapeutical apparatus of extracorporeal type as mentioned
above, the use of the ultrasonic wave for observing the location of a
calculus and for aiming fails to provide a tomographic image of good
quality because of the spacing between the apparatus and the patient. This
makes it difficult to aim the apparatus.
In addition, in the apparatus described above, the entire shock wave
generator has been moved in order to bring the focal point of the shock
wave into alignment with the calculus. However, because the shock wave
generator (including the water bag) is of an increased weight, an
extensive unit is required for such movement and the apparatus lacks
speed.
On the other hand, a calculus or tumor which is to be treated by such an
apparatus tends to move in response to breathing or movement of blood
vessel, and thus may be displaced from the focal point of the ultrasonic
beam. In such instance, the focal point of the ultrasonic beam must be
aligned with a region to be treated to avoid wasteful generation of an
ultrasonic wave. This increases the length of time required for the
therapy and also jeopardizes normal tissues. Movement caused by breathing
may be rapid enough to prevent automatic tracking of the focal point of
the ultrasonic beam on the moving calculus since the water bag itself has
a given magnitude.
Almost all apparatus of the kind described utilize a devoted bed on which a
patient is positioned in a supine posture. The bed includes a table
section supporting an upper region of a patient including his shoulder and
head and another table section supporting a lower section extending from
the waist to the feet, leaving a free space between the breast and the
abdomen. A patient is laid in a supine posture on the bed, and the
measuring apparatus as well as a unit for generating therapeutical energy
are brought close to or into abutment against the patient to perform the
treatment. Accordingly, the patient has a small degree of freedom during
the therapy, which restricts the space requirement for the measuring
apparatus and the energy generating apparatus. Specifically, with an X-ray
measuring apparatus, it is only possible to cause the X-ray to transmit
through the physical body of a patient. With an ultrasonic measuring
apparatus, it is only possible to move the ultrasonic vibrator along the
surface of the physical body.
There has been no capability to provide an efficient, fine adjustment of
the angle with which the X-ray transmits or the angle at which the
ultrasonic wave is emitted. It has been impossible to locate a shock wave
generator at an angle which avoids the lung when treating a biliary
calculus or to adjust the angle at which the shock wave is emitted to an
efficient angle. It has only been possible to guide the shock wave
generator along the physical body of a patient.
Usually, a supine posture is chosen for therapy of a biliary calculus while
either a supine or prone posture is chosen for treating a renal calculus,
and it is unfavorable that a posture used for the therapy be restricted by
a devoted bed.
Hospitals usually have an X-ray apparatus and an ultrasonic diagnostic
apparatus, and therefore it is uneconomical for the hospital to purchase a
separate extracorporeal therapeutical apparatus with a devoted bed. It is
desirable that a therapeutical apparatus of extracorporeal type be
provided which uses a common bed which allows a free choice of either
supine or prone posture.
Thus, an ordinary hospital is usually provided with an X-ray unit or
ultrasonic diagnostic apparatus which may be used as the measuring
apparatus mentioned above as well as associated patient beds. If an
extracorporeal therapeutical apparatus as mentioned above must be provided
anew, an increased demand in space requirement and additional cost result.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a therapeutical
apparatus of extracorporeal type which permits a choice of therapy
postures and which improves economy and which is capable of adjusting an
angle with which a measuring apparatus makes an observation as well as an
angle with which energy from a therapeutical energy generator is emitted
or directed.
It is a second object of the invention to provide a therapeutical apparatus
of extracorporeal type which requires less space and reduces cost while
utilizing an ultrasonic diagnostic apparatus or X-ray unit which is
already available in the hospital.
It is a third object of the invention to eliminate disadvantages of the
prior art, by providing an ultrasonic therapeutical apparatus having
enhanced measurement capabilities while facilitating the location of a
calculus before therapy and also enabling an accurate tracking of the
calculus for efficient therapy.
It is a fourth object of the invention to provide a therapeutical apparatus
of extracorporeal type which is capable of detecting movement of a
calculus to bring a focus into alignment with the calculus which has
quickly moved, thus providing efficient and dependable therapy.
It is a fifth object of the invention to provide a therapeutical apparatus
of extracorporeal type which is capable of reliably bringing the focal
point of a shock wave into alignment with a recognized calculus in an
accurate manner while avoiding adverse influence upon other organs, thus
further improving the fracture efficiency and reducing the length of time
required for the therapy while avoiding any pains to the patient.
It is a sixth object of the invention to provide an ultrasonic probe having
a simplified construction and exhibiting an increased efficiency. In
accordance with the invention, the patient may assume any posture during
therapy. The angle at which an observation is made as well as the angle at
which the shock wave used for the therapy is emitted can be accurately
adjusted to achieve a most efficient operation. The apparatus of the
invention may be efficiently used in combination with any other instrument
such as an X-ray unit. This avoids unnecessary expenses and reduces space
requirements while improving the degree of freedom and economy.
In accordance with the invention, an ultrasonic shock wave is radiated in
recognition of the location within a specified area (an area of
interest--AOI) where a calculus exists, thus eliminating a wasteful
emission of an ultrasonic shock wave to provide a further enhanced therapy
efficiency.
In accordance with the invention, an ultrasonic probe allows an increased
coverage for observation, facilitating the location of a calculus before
it is treated. In this manner, any resort to a separate ultrasonic
observation unit as has been done conventionally is avoided. The locating
and the automatic tracking of a calculus enable the length of time
required for the therapy to be reduced and any pain caused to the patient
to be diminished, because an efficient treatment is achieved.
In accordance with the invention, the focal point of an ultrasonic shock
wave may be brought into alignment with any object being treated which may
move rapidly as a result of breathing, by merely choosing ultrasonic
vibrators which are to be driven while maintaining a shock wave generator
at a fixed position. The focal point is brought into alignment with the
object by an electronic technique which utilizes a CPU to drive a drive
circuit, and hence the arrangement is compact in construction and
efficient in achieving the therapy of an object such as a calculus.
Additionally, if a calculus or tumor changes its position because of the
patient's breathing, the ultrasonic wave may be maintained focussed on the
object being treated. This improves the efficiency of the therapy and
enhances the safety of the therapy by avoiding concentration of an
ultrasonic wave upon areas which are unrelated to treatment. This is
achieved by feeding a digital signal representing the location of a
calculus or tumor detected by the ultrasonic probe to a CPU, which then
automatically focuses the ultrasonic wave on an area to be treated, thus
avoiding manual intervention and allowing an automatic tracking.
Additionally, in accordance with the invention, an image representing a
spatial location of a focus within the patient may be obtained by driving
ultrasonic vibrators. Data representing the distribution of the intensity
of the ultrasonic wave which is previously calculated is superimposed upon
the image to provide a color display, whereby the location of the calculus
may be readily and reliably positioned to a point where the intensity of
the shock wave is at its maximum. This also allows a decision to see if
any organ such as a lung, intestine or bones which are sensitive to the
shock wave is located within a region where the intensity of the shock
wave is significant. In this manner, any damage to such organ may be
avoided by changing the posture of the patient or by moving the shock wave
generator.
Other features and advantages of the present invention will become apparent
from the following description of the invention, with reference to the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of an apparatus according to a first embodiment
of the invention;
FIGS. 2 and 3 are a fragmentary rear view and a side elevation,
illustrating manners of operating the apparatus illustrated in FIG. 1;
FIG. 4 is a schematic view of a therapeutical apparatus according to a
second embodiment of the invention;
FIG. 5 is a side elevation of another form of guide arm;
FIG. 6 is a side elevation of an apparatus according to the invention in
combination with an X-ray unit;
FIG. 7 is a side elevation of another form of the therapeutical apparatus;
FIG. 8 is a perspective view of an apparatus according to a third
embodiment of the invention;
FIG. 9 is a fragmentary, enlarged, longitudinal section illustrating one
manner of use of the apparatus illustrated in FIG. 8;
FIG. 10 is a longitudinal section of a water bag in its shrunk condition;
FIG. 11 is a schematic view, partly in longitudinal section, of an
apparatus according to a fourth embodiment of the invention;
FIG. 12 is a perspective view of an apparatus according to a fifth
embodiment of the invention;
FIG. 13 is an enlarged, fragmentary cross sectional view of the apparatus
illustrated in FIG. 12;
FIG. 14 is a block diagram of an apparatus according to a sixth embodiment
of the invention;
FIG. 15 is an illustration of a monitor screen of a display unit
illustrated in FIG. 14;
FIG. 16 is a flowchart illustrating the operation of an apparatus according
to the invention;
FIG. 17 is a flowchart illustrating the operation of an apparatus according
to a seventh embodiment of the invention;
FIG. 18 is a block diagram of an apparatus according to an eighth
embodiment of the invention;
FIG. 19 is a fragmentary cross sectional view of an apparatus according to
a ninth embodiment of the invention;
FIG. 20 is a schematic illustration of an apparatus according to a tenth
embodiment of the invention;
FIG. 21 is a block diagram of an apparatus according to an eleventh
embodiment of the invention;
FIG. 22 is a diagram illustrating the relationship between the wave surface
and the focal point in the arrangement illustrated in FIG. 21;
FIG. 23 graphically illustrates the waveforms of ultrasonic signals from
individual piezoelectric elements used in the arrangement of FIG. 21;
FIG. 24 is a flowchart of the operation of the arrangement illustrated in
FIG. 21;
FIG. 25 is a perspective view of an apparatus according to a twelfth
embodiment of the invention;
FIGS. 26A, B and C illustrate an apparatus according to a thirteenth
embodiment of the invention; FIG. 26A being a cross sectional view of the
relationship between an acoustical prism and a focal point; FIG. 26B being
a perspective view of an acoustical prism; and FIG. 26C being an enlarged,
fragmentary cross sectional view of an acoustical prism;
FIG. 27 is a schematic illustration of an apparatus according to a
fourteenth embodiment of the invention;
FIG. 28 is a schematic illustration of an apparatus according to a
fifteenth embodiment of the invention;
FIG. 29 is a diagram illustrating an echo-through which may occur in a
tomographic image formed by an ultrasonic probe;
FIG. 30 is a schematic illustration of an apparatus according to a
sixteenth embodiment of the invention;
FIG. 31 is a diagram of an example of angle of rotation of an ultrasonic
probe used in the apparatus of FIG. 30;
FIG. 32 illustrates several B-mode images at different angles of rotation
of the probe;
FIG. 33 is a flowchart illustrating a procedure which is utilized in the
sixteenth embodiment to bring a calculus into the focal point of an array
of vibrators;
FIG. 34 illustrates a B-mode image, specifically illustrating the
relationship between a calculus and the focal point of an array of
ultrasonic vibrators on a P2 image plane illustrated in FIG. 32;
FIG. 35 shows a B-mode image, illustrating another use of the apparatus
illustrated in FIG. 30;
FIG. 36 is a block diagram of display means used in an apparatus according
to a seventeenth embodiment of the invention;
FIG. 37 is a diagram illustrating a data screen of the display;
FIG. 38 is a block diagram of another form of display means;
FIG. 39 is a longitudinal section through an ultrasonic probe and a shock
wave generator which are used in an apparatus according to an eighteenth
embodiment of the invention;
FIG. 40 is a plan view of the probe illustrated in FIG. 39;
FIG. 41 is an enlarged, fragmentary longitudinal section of the probe
illustrated in FIG. 39;
FIGS. 42 and 43 are a perspective view and a plan view of another form of
probe;
FIG. 44 is a schematic illustration of a conventional apparatus;
FIG. 45 is a block diagram illustrating the sequence of operation of the
apparatus illustrated in FIG. 44; and
FIG. 46 is a diagram illustrating a conventional data display screen.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, the invention will now be described with
reference to several embodiments thereof. In the description to follow, a
therapeutical apparatus of extracorporeal type is constructed as a
calculus fracture apparatus, but it should be understood that the
invention is not limited in its application to the fracture of a calculus.
The apparatus 1 of FIG. 1 includes a movable body 2 on which an operating
keyboard 3 and a monitor display 4 are installed. An operating head 7 is
also carried. The head 7 guides a measuring apparatus 5 and a
therapeutical energy generator 6 to a desired angular position.
The head 7 is mounted on the top end of a rotatable shaft 8 which is
vertically supported within the body 2. The shaft 8 can be elevated up and
down to permit vertical movement of the head 7, which is also movable
toward and away from a patient 11 by a mechanism, not shown. The head 7
carries a support shaft 9 which projects horizontally and forwardly, with
a guide arm 10 mounted on the free end of the support shaft 9. The
measuring apparatus 5 is slidably mounted on the arm 10 by a movable mount
5a, and the energy generator 6 is also slidably mounted on the arm 10 by a
movable mount 6a. The guide arm 10 is arcuate or semicircular in the
present embodiment so that both the measuring apparatus 5 and the
generator 6 may be moved around one-half the circumference of the patient
11. The support shaft 9 is also rotatable around its axis, whereby the
guide arm 10 is rotatable through 360.degree. around an extension of the
axis of the support shaft 9.
The measuring apparatus 5 (mounted on the movable mount 5a) includes an
ultrasonic vibrator which performs a sector scan, for example, radiating
an ultrasonic wave toward the patient 11 to detect the location of a
calculus 13 which may be located within a kidney 12 of the patient. The
detected renal calculus 13 is displayed on the screen of the monitor
display 4 (which may include a cathode ray tube).
The therapeutical energy generator 6 (mounted on the movable mount 6a)
includes a high tension discharge type source for generating shock wave
energy. The source is focussed upon the renal calculus 13 within the
patient 11, through an interposed water bag 14 (such as GOATEX
(trademark)) which is filled with a shock wave transmitting medium (such
as water) for fracturing the calculus 13.
In operation, the patient 11 usually lies on an ordinary bed 15 in prone
posture, and the body 2 is moved close to the patient. By adjusting the
operating head 7 back and forth and up and down, the guide arm 10 is
brought in spaced, opposing relationship with the circumference of the
patient 11 to facilitate detection and fracture of the calculus by
bringing the measuring apparatus 5 and the energy generator 6 close to or
in abutment against the surface of the patient. As illustrated in FIG. 2,
the support shaft 9 may be rotated around its axis to bring the guide arm
10 to an inclined position with respect to the surface of the patient so
that the generator 6 may be brought to an angular position to maximize
fracture efficiency or where the location of a lung or the like may be
avoided from the path of the shock wave energy.
Where the patient 11 lies on the bed 15 in supine posture as illustrated in
FIG. 2, the support shaft 9 may be rotated through 180.degree. to position
the guide arm 10 in the space below the bed 15, whereby the measuring
apparatus 5 and the generator 6 are brought close to or into abutment
against the patient 11 from the underside thereof for therapy.
FIG. 4 is a schematic illustration of an apparatus according to a second
embodiment of the invention. This apparatus differs from the first
embodiment in that the energy generator 6 includes an ultrasonic shock
wave generator 16. Specifically, the generator 16 includes a mounting
plate 17 in the form of a spherical shell. A multiplicity of ultrasonic
vibrators 18, formed by piezoelectric elements, are secured in a mosaic
pattern on the internal surface of the shell so that the front surface of
each element (on which a shock wave is generated) faces the patient 11. A
water bag 19 of a material such as GOATEX (trademark) which includes
liquid injection means and pressure control means is interposed between
the generator and the patient 11. The bag 19 is filled with a shock wave
transmitting liquid such as water. An ultrasonic measuring apparatus 20
which is adapted for a linear scan or a sector scan is mounted centrally
on the mounting plate 17.
The ultrasonic energy generator 16 is movably mounted on the guide arm 10
by a movable mount 16a. In other respects, the arrangement is similar to
the first embodiment, and this embodiment operates similarly and with a
similar effect as in the first embodiment.
In FIG. 5, the guide arm 10 of the first embodiment is replaced by a C-ring
shaped guide arm 21 on which the measuring apparatus 5 and the
therapeutical energy generator 6 may be movably mounted. This facilitates
changing the posture of the patient. This permits utilization of an X-ray
unit having a C-shaped guide arm as the measuring apparatus associated
with the therapeutical apparatus of the invention.
Specifically, as illustrated in FIG. 6, an X-ray unit 25 carries a C-shaped
guide arm 24 on which an X-ray emitter 22 and an image intensifier 23
(which is an X-ray receptor and includes photomultipliers) are mounted in
opposing relationship. The unit 25 may be disposed along one side of the
patient 11 lying on the bed 15 while the therapeutical apparatus 1
(including either the therapeutical energy generator 6 or 16) mounted on
the guide arm 10 may be disposed on the other side. In this manner, the
location of the calculus 13 may be detected by the X-ray observation unit
25, and then the therapeutical apparatus 1 may be activated to fracture
the calculus 13.
The therapeutical apparatus of the invention may be used in combination
with an endoscope. As illustrated in FIG. 7, the body 2 of the
therapeutical apparatus may be provided with shelves 26 on which a light
source unit 27 for the endoscope and a treatment tool 28 may be
conveniently located.
FIGS. 8 to 10 illustrate a third embodiment of the invention which utilizes
an X-ray unit (already provided in the hospital) as the measuring
apparatus. Specifically, the X-ray unit includes an X-ray emitter 32 on
which a therapeutical energy generator 31 is detachably mounted. The
emitter 32 is movable up and down above a surgical bed 33 and has an
arm-shaped mounting member 48 secured thereto at a downward angle. The
generator 31 is detachably mounted on the mounting member 48 by mounting
screws 49. The generator 31 is of a high tension discharge type and
includes an external housing 39 having a focussing reflector 40 disposed
in its free end. The reflector has an elliptical surface. A discharge
electrode 42 is located at one of the foci of the elliptical surface, and
the opening of the reflector 40 is covered by a flexible water bag 41
which is filled with a shock wave transmitting medium 43 such as water,
thus filling the space between the external surface of a patient 50 and
the discharge electrode 42. Piping 44, 45 inside of the housing 39
supplies or discharges water to and from the bag 41. The electrode 42 is
connected through a connection cord 46 passing through the housing 39 to a
source of high tension 34, whereby a discharge voltage may be applied to
the electrode. An ultrasonic probe 47 (which is used as an auxiliary
measuring apparatus) is located along the underside of the housing 39.
The X-ray emitter 32 is supported by a support member 36 to be movable
vertically above the surgical bed 33. The bed is conventionally
horizontally translatable in two dimensions. The X-ray is transmitted
through the patient 50 lying on the bed to be received by an X-ray
receptor or an image intensifier 35 (including photomultipliers) located
below the bed 33. The arrangement may include a monitor 37 which indicates
the focus of the shock wave and an X-ray monitor 38. The patient's kidney
50 is indicated at 51, with a calculus 52 located therein.
In operation, when the energy generator 31 is mounted on the X-ray
measuring apparatus, the system is adjusted so that the axes of ultrasonic
energy and X-ray radiation intersect each other at the calculus 52, as
indicated in FIG. 9. The apparatus is connected to the source 34 and to a
source of water, not shown, through the piping 44, 45. The patient 50 then
lies on the bed 33. The X-ray unit is then operated to cause the X-ray to
pass through the kidney 51 to observe and detect the calculus 52. At this
time, the water bag 41 should be shrunk as indicated in FIG. 10 to
approach the opening of the reflector 40, by removing the water therefrom,
to prevent the bag from interfering with the X-ray unit. After the
calculus 52 is detected, the water is supplied to the water bag 41 to
expand it, and the support member 36 is operated to bring the bag into
close contact with the patient. While observing the monitor 37, the
location of the calculus 52 is brought to the other focal point of the
elliptical reflector 40. A high tension is then applied to the electrode
42 to cause its discharge, whereupon shock wave energy is focussed upon
the calculus 52 located within the kidney 51, thus fracturing it as
intended to allow it to be digested in a natural manner.
While the apparatus may be used in combination with an X-ray unit to detect
the location of a calculus, the location of a calculus may also be
detected by an ultrasonic probe 47 mounted on a housing 39. In addition,
the energy generator 31 may be detachably mounted on the image intensifier
35 of the X-ray unit with a similar effect.
FIG. 11 is a longitudinal section through an apparatus according to a
fourth embodiment of the invention, which is similar to the apparatus
illustrated in FIGS. 8 and 9. Accordingly, similar parts are designated by
corresponding numerals without repeating their description. Specifically,
the only difference between the embodiments is that a therapeutical energy
generator 31A is detachably mounted on the surgical bed in distinction to
the energy generator 31 which is detachably mounted on the X-ray emitter
32 or the image intensifier 35 in the embodiment of FIGS. 8 and 9. Thus,
referring to FIG. 11, the generator 31A is detachably mounted on a
surgical bed 33A by mounting screws 49A with a mounting member 48A
interposed therebetween. When the energy generator is directly mounted on
the bed 33A, the generator 31A may be more firmly secured to improve
stability during use. The apparatus functions in a similar manner and
achieves a similar effect as the apparatus illustrated in FIGS. 8 and 9.
FIG. 12 is a schematic illustration of an apparatus according to a fifth
embodiment of the invention which is used in combination with an existing
ultrasonic diagnostic apparatus utilized as a measuring apparatus, with a
therapeutical energy generator detachably mounted thereon. Specifically,
FIG. 12 illustrates a therapeutical energy generator 31B, an ultrasonic
diagnostic observation apparatus 32A, an observation monitor 53, an
ultrasonic probe of mechanical scan type associated with the apparatus
32A, and an arm 55 which carries the probe 54 in a movable manner. As
illustrated, the ultrasonic diagnostic apparatus 32A is free to move
above, and the probe 54 may be freely positioned relative to an affected
part 57 of a patient 56 (see FIG. 13) by means of the arm 56.
Referring to FIG. 13, the therapeutical energy generator 31B includes a
body 58 in the form of a cup-shaped casing having an opening 59 centrally
in its top in which the probe 54 is fitted and having a bottom opening
which is closed by a water bag 60. An array of piezoelectric elements 65
is disposed along a spherical surface on the internal upper surface of the
body 58. The water bag 60 is filled with water 61 acting as an ultrasonic
wave transmitting medium, and an O-ring 62 is fitted around the top
opening 59 to maintain the body 58 watertight against the probe 54. The
top of the body 58 is integrally formed with three threaded lugs 63, which
are engaged by mounting screws 64 to permit the apparatus 31B to be
detachably mounted on the probe 54 of the ultrasonic diagnostic apparatus
32A. The piezoelectric elements 65 are connected to a drive unit 66, and
shock wave energy generated by the piezoelectric elements 65 is focussed
upon the affected part 57 (such as the calculus of the pa | | |
