This application is based upon and claims the benefit of priority from prior Japanese patent applications No. 2011-279712 filed on Dec. 21, 2011 and 2012-240825 filed on Oct. 31, 2012, the entire contents of which are incorporated herein by reference.
The presently disclosed subject matter relates to a cuff which is to be used in a blood pressure measurement or the like, and also to a method of observing a tissue under pressure by using it.
In the field of medicine, the central venous pressure (CVP) is sometimes measured during treatment of a critically ill patient. In such a measurement, a catheter is inserted into and indwelled in the superior or inferior vena cava of the patient, and the blood pressure in the region is measured. The measurement of the central venous pressure is performed in order to, for example, check whether the balance of the circulatory blood volume in the living body of the patient is lost because of bleeding, dehydration, or the like, or whether heart failure or the like occurs or not.
As described above, the related-art measurement of the central venous pressure is performed while a catheter is inserted into and indwelled in the body of the patient. Therefore, the physical burden on the patient is large. Consequently, it is requested to develop a less or non-invasive method of measuring the central venous pressure.
On the other hand, Non-patent Document 1 below discloses a technique in which an ultrasonic probe in which a pressure sensor is attached to the tip end is pressed against a region of the forearm, the state of the vein in the region is checked on a monitor, the pressure at the timing when the vein collapses is measured, and the pressure is determined as a pressure (hereinafter, referred to as the alternative central venous pressure) that functions as an alternative to the central venous pressure.
Non- or less-invasive medical techniques have been developed also in fields other than the measurement of the central venous pressure. Examples of such techniques are the apparatus for examining a breast disclosed in Patent Document 1, and the method which is described in Non-patent Document 2 and which is to be used in the diagnosis of an ectopic ureterocele.
The apparatus for examining a breast disclosed in Patent Document 1 is used in breast cancer screening or the like. The apparatus for examining abreast has: an ultrasonic array probe; a sealing liquid container which accommodates liquid and the ultrasonic array probe, and which partly has a stretchable film through which an ultrasonic wave is transmissible; a contact pressure adjusting unit which, in accordance with the a specimen, adjusts a contact pressure between the specimen and the stretchable film; an ultrasonic wave transmitting/receiving circuit which causes the ultrasonic array probe to transmit and receive an ultrasonic wave; an image producing unit which produces an image of the specimen from a signal that is received by the ultrasonic wave transmitting/receiving circuit; and an image displaying unit which displays the produced image. According to the configuration, breasts of various sizes can be pressed into a shape which is adequate for displaying an image.
The method of Non-patent Document 2 is used in diagnosis of disease which is called an ectopic ureterocele, and in which an ureterocele develops in a state where the ureter dose not open in the trigone of the bladder. According to the method of Non-patent Document 2, in the case where an ultrasonic examination is performed in a state where the hydroureter in the flank is pressed, in order to diagnose an ectopic ureterocele, when an ectopic ureterocele exists, the ureterocele can be clearly displayed in an echo image due to an ultrasonic wave.
(Patent Document 1) JP-A-2007-282960
(Non-patent Document 1) Christoph Thalhammer et al. “Noninvasive Central Venous Pressure Measurement by Controlled Compression Sonography at the Forearm,” Journal of the American College of Cardiology, Elseveir Inc., [online], Jan. 17, 2011, Vol. 50, No. 16, p. 1584-1589, Internet <URL:http://content.onlinejacc.org/cgi/content/full/50/16/1584>
(Non-patent Document 2) Gotaro KURASAWA et al. “Sokufukubu Appakuho niyoru Choonpa Kensa ga Shindan ni Yuyodeatta Isyosei Nyokanryu no Ichirai,” Nippon Syoni Jinzobyo Gakkai Zashi, Nippon Syoni Jinzobyo Gakkai, 1996, Vol. 9, No. 1, p. 49-52
In the method of Non-patent Document 1, a pressure sensor-equipped ultrasonic probe pressurizes the vein in the forearm in the range of from 0 mmHg to 50 mmHg at intervals of 5 mmHg, and the pressure at the timing when the blood vessel collapses is determined as a pressure corresponding to the central venous pressure. In the method of Non-patent Document 1, however, the probe is pressed by the hand, and therefore the pressure is hardly maintained constant. Consequently, it is difficult to accurately measure the alternative central venous pressure.
A cuff is used for measuring the blood pressure of the artery. If a cuff is used, the whole periphery of the vein can be constantly pressurized also in measurement of the alternative central venous pressure (the pressure is not limited to the venous pressure in the forearm, and means the venous pressure of the vein in a region where the pressure can be measured by using a cuff, and the same shall apply hereinafter). However, a related-art cuff cannot observe a tissue such as the vein under pressure, and therefore cannot measure the alternative central venous pressure.
In the examining apparatus disclosed in Patent Document 1, the structure of the sealing liquid container is complicated, and therefore a dedicated apparatus is necessary. If such a dedicated apparatus is necessary in the examination of breast cancer, an economic burden is imposed on a hospital which introduces the apparatus, and a patient who uses the apparatus. Therefore, the breast cancer screening cannot be easily performed.
In Non-patent Document 2, the manner of pressing the hydroureter in the flank is not described in detail. When an apparatus for pressing the flank is not prepared, a technician such as a doctor presses the region. In the case where, in order to display an ureterocele, a technician manually presses the hydroureter in the flank with the hand, however, it is difficult to apply a constant pressing force, and therefore a clear display of the hydroureter can be hardly obtained.
The presently disclosed subject matter may provide a cuff which enables the state of a tissue under pressure to be observed, and an examination or the like to be easily performed, and a method of observing a tissue under pressure by using it.
The cuff may comprise: a belt-like body which is adapted to be wrapped around a desired region of a living body; a fixing portion which is provided in the body, and which is configured to fix the body in a state where the body is adapted to be wrapped around the region of the living body; a pressurizing portion which is provided in the body, and to which a fluid pressure is to be supplied to be inflated to pressurize the region of the living body; and an ultrasonic transmissive portion which is provided in the body, and through which an ultrasonic wave for observing a tissue in the region of the living body is transmissible.
The region of the living body may be one of four limbs.
The region of the living body may be breast, and the fixing portion may be configured to fix the body in a state where the body is adapted to be wrapped around a chest so as to cover the breast.
The region of the living body may be abdomen.
The ultrasonic transmissive portion may be configured by providing, in the body, a window portion formed by a member having ultrasonic transmissive properties.
The ultrasonic transmissive portion maybe configured by forming the body by a member having ultrasonic transmissive properties.
The ultrasonic transmissive portion may be disposed in a position through which an extension line of a centerline of the pressurizing portion in a direction intersecting with a direction of wrapping the body around the region of the living body passes.
The ultrasonic transmissive portion may be transparent.
The tissue observing method may comprise: wrapping the body of the cuff around the region of the living body; fixing, by the fixing portion, the body in a state where the ultrasonic transmissive portion faces against an observation region of the region of the living body; supplying the fluid pressure to the pressurizing portion to pressurize the region of the living body; and irradiating an ultrasonic wave from an ultrasonic probe through the ultrasonic transmissive portion to observe a tissue of the observation region of the region of the living body.
Hereinafter, embodiments of the presently disclosed subject matter will be described with reference to the accompanying drawings. The following description shall not be interpreted to limit the technical scope and meaning of terms of the claims. In the drawings, the dimension ratios are exaggerated for the sake of convenience in description, and may be sometimes different from the actual ratios.
The pump 11 supplies a predetermined flow amount of the air to an air bag 3 which is housed in the cuff 1, and which is described later. The control valve 12 is controlled by the controlling section 14 to switch air supply/exhaustion to and from the air bag 3. The pressure sensor 13 detects the pressure applied to the air bag 3, and sends a signal indicative of the pressure to the controlling section 14. The controlling section 14 calculates the pressure applied to a desired region of the living body such as the upper or lower limb from the pressure signal obtained from the pressure sensor 13, and controls the flow amount to be supplied from the pump 11.
When the process of measuring the pressure is ended, the controlling section 14 controls the control valve 12 to exhaust the air in the air bag 3, and then causes the pump 11 to stop. Independent from the pressure measurement, the controlling section 14 performs an image process on a signal which is obtained by touching the ultrasonic probe 15 against a measurement region, and controls the display device 16 to display an echo image. The display device 16 displays various results such as the maximal and minimal blood pressures, the echo image, and the like which are processed by the controlling section 14. Alternatively, the display device 16 may be configured by a device on which the blood pressure is displayed, and another device on which the echo image is displayed.
Referring to
As shown in
The fixing portion 4 is configured by a surface fastener. The surface fastener includes a hook surface 4a which is disposed in a left end portion in
The hook surface 4a and the loop surface 4b are formed by cutting away respective necessary amounts from roll-like members, and then sewn to the body 2. In the embodiment, the hook surface 4a is placed on the side which is inside when the cuff 1 is wrapped, and the loop surface 4b is placed on the outer side. Alternatively, the hook surface 4a may be placed on the outer side, and the loop surface 4b may be placed on the inner side.
As shown in
The air bag 3 is placed in a right end portion in
As shown in
In the illustrated embodiment, the ultrasonic transmissive portion A is configured by placing the window portion B formed by a member having ultrasonic transmissive properties, in the body 2. As the member having ultrasonic transmissive properties, the ultrasonic transmissive film 21 is used. The material forming the ultrasonic transmissive film is not particularly limited. For example, polymethylpentene which is called TPX (registered trademark) may be used.
As shown in
As shown in
Moreover, it is preferable that the ultrasonic transmissive portion A is transparent, because of the following reason. According to the configuration, the measurement region can be viewed from the above the ultrasonic transmissive film 21, and the convenience in the case where the cuff 1 is to be adjusted to the position of the measurement region can be improved.
Referring to
The blood pressure measurement using the cuff 1 of the embodiment will be described taking as an example the case where the venous pressure in the right forearm is measured as the alternative central venous pressure. First, the cuff 1 is wrapped around the right forearm of the patient to be attached thereto, and the cuff 1 is adjusted by rotating it so that the portion where the ultrasonic transmissive film 21 is formed is above the position of the vein which is the measurement object.
After the portion of the cuff 1 where the ultrasonic transmissive film 21 is formed is located above the vein, a gel through which an ultrasonic wave is transmissible is applied onto the ultrasonic transmissive film 21. The gel may be further applied between the ultrasonic transmissive film 21 and the forearm region which is the measurement region.
While touching the ultrasonic probe 15 against the ultrasonic transmissive film 21 to which the gel is applied, the air bag 3 of the cuff 1 is inflated by the pump 11 to pressurize the measurement region, and the condition of the blood vessel is observed on the display device 16.
In the related-art measurement of the alternative central venous pressure, a pressure sensor is attached to a probe, and a pressure is applied by the hand. Therefore, it is difficult to pressurize the vein at a constant pressure. Even by using a related-art cuff, a tissue under pressure cannot be observed, and the alternative central venous pressure cannot be measured.
In the cuff 1 of the embodiment, by contrast, the ultrasonic transmissive film 21 is disposed in the cuff 1, and therefore, while the whole periphery of the measurement region is evenly pressurized at a constant pressure, the state of a tissue under pressure can be observed. Consequently, it is possible to measure the alternative central venous pressure.
The cuff 1 of the embodiment can be used also in an index which is called ABI, and in which a blood pressure measurement is employed. The ABI (Ankle Brachial Index) indicates the ratio of the maximal blood pressure of the ankle to that of the upper arm, and is also called the ratio of ankle pressure to brachial pressure.
The ABI is obtained by measuring the blood pressures of the upper arm and the ankle in a supine position. In a healthy person, the blood pressure of the ankle is slightly higher than that of the upper arm. In the case where a constricted or obstructed part exists in a blood vessel of the ankle, the blood flow is impaired, and the blood pressure of the ankle is lowered as compared to that of the upper arm, so that the ABI shows a low value. The ABI is measured in the first inspection of arteriosclerosis obliterans.
Even in the case where a constricted part exists in a blood vessel of the foot, when calcification occurs in a vessel of the blood pressure measurement region of the ankle, the vessel is hardly crushed even by pressurization of a cuff, and therefore the situation where the ABI does not show a low value is produced. In the case where calcification occurs as described above, when a blood pressure measurement is performed by using a related-art cuff, it is impossible to adequately determine whether arteriosclerosis obliterans occurs or not.
Even in such a case, according to the cuff 1 of the embodiment, an ultrasonic echo image of a vessel region of the foot can be produced, so that the state of the tissue of the measurement region under pressure can be observed. Therefore, it is possible to check whether calcification occurs in the measurement region or not, and the reliability of the ABI can be improved.
As described above, the cuff 1 of the embodiment is configured so as to have: the body 2; the fixing portion 4 which is disposed in the body 2, and which fixes the body 2 to a state where it is fixed to the desired region of the living body such as the forearm; the air bag 3 which is disposed in the body 2, and which is inflated by supplying a fluid pressure to pressurize the desired region of the living body; and the ultrasonic transmissive portion A which is disposed in the body 2, and through which an ultrasonic wave for observing a tissue in the desired region of the living body is transmissible. Therefore, the ultrasonic transmissive portion A enables the state of a tissue under pressure to be observed.
The cuff 1 is wrapped around the desired region of the living body, the ultrasonic transmissive portion A is caused to face against an observation region, the body 2 is fixed to the desired region of the living body by the fixing portion 4, and the desired region of the living body is pressurized by the air bag 3. Then, the ultrasonic wave irradiated from the ultrasonic probe 15 is caused to transmit through the ultrasonic transmissive portion A to impinge on the observation region, thereby enabling a measurement of a blood pressure such as the alternative central venous pressure to be accurately performed.
The ultrasonic transmissive portion A in the embodiment is configured by placing the window portion B formed by the ultrasonic transmissive film 21. When a window portion is disposed in a related-art cuff and an ultrasonic transmissive film is placed in the portion, therefore, it is possible to form a cuff which enables the state of a tissue under pressure to be observed.
The ultrasonic transmissive portion A is placed so that an extension line of the centerline O, which is parallel to the direction of wrapping the body 2 around the desired region of the living body, of the airbag 3 in the direction intersecting with the direction of wrapping the body 2 around the desired region of the living body passes through the ultrasonic transmissive portion A. In the cuff 1, therefore, the ultrasonic transmissive portion A can be placed in a location where a blood vessel can be sufficiently pressurized, so that the state of the blood vessel can be adequately checked.
Since the ultrasonic transmissive portion A is transparent, the ultrasonic transmissive portion A can be adjusted to the measurement region by means of a visual check. Therefore, the convenience in the case where the cuff 1 is to be attached to the measurement region can be improved.
The invention is not limited to the above-described embodiment, and can be variously modified within the scope of the appended claims.
Although the embodiment in which the ultrasonic transmissive portion A is configured by placing the window portion B formed by the member having ultrasonic transmissive properties in the body 2 has been described, the invention is not limited to this. For example, the ultrasonic transmissive portion may be configured by forming the body by a member having ultrasonic transmissive properties. According to the configuration, the range where the ultrasonic probe 15 can be placed can be expanded as compared to the case where a member having ultrasonic transmissive properties is partly used, and therefore the position adjustment of the cuff can be facilitated.
The embodiment in which the housing pocket for housing the air bag 3 is formed in the body 2 has been described. The housing pocket is required simply to house the air bag 3. In the case where the pocket is formed by overlapping two sheets of the material constituting the body 2, such as polyester, therefore, the other portion including the hook surface 4a and the like may be configured by one sheet of the material. This is applicable also to a cuff in which the body is formed by an ultrasonic transmissive film.
Although the embodiment in which the ultrasonic transmissive film 21 is configured by polymethylpentene which is called TPX or the like has been described, the invention is not limited to this, and another configuration may be employed. In order to prevent an ultrasonic wave from being reflected from an intermediate point, the ultrasonic transmissive film 21 may be configured by a material which is similar in acoustic impedance to the body tissue.
The embodiment in which the ultrasonic wave transmission portion A is configured so as to be transparent has been described. Since, among materials through which an ultrasonic wave is transmissible, there are those which are not transparent, the ultrasonic wave transmission portion A may not always be transparent.
Next, an experiment in which the cuff of the embodiment was used, and which was conducted with respect to a pressure acting on a region immediately below the ultrasonic transmissive film will be described.
In the experiment, a cuff in which a window portion formed by an ultrasonic transmissive film is placed in the body, and that in which the body is formed by an ultrasonic transmissive film were used. As shown in
The pressure acting between the air bag 3 and the arm region 6 was detected by the pressure sensor 13 shown in
By contrast, with respect to the pressure immediately below the ultrasonic transmissive film, when the pressure is detected while placing a bag filled with air between the ultrasonic transmissive film and the arm region 6, the bag filled with air collapses at a pressure of a certain level or higher, and it is impossible to detect a pressure which is higher than the level. Therefore, a bag 7 having a size which is similar to that of the ultrasonic transmissive film was filled with water, and placed between the ultrasonic transmissive film and the arm region 6. A pressure sensor was attached to the bag 7 filled with water, and a pressure waveform was output.
The solid-line part and the broken-line part in each of the figures substantially overlap with each other, and therefore the broken-line part is additionally drawn in the vicinity of the solid-line part. The rates of pressurizing and depressurizing the arm region in
As shown in
Next, Embodiment 2 of the presently disclosed subject matter will be described.
In Embodiment 1 above-described, when the cuff 1 is used in a limb region such as the upper limb or the lower limb, the alternative central venous pressure can be accurately measured while pressurizing the region at a constant pressure, and, when the cuff is used in the blood pressure measurement for calculating the ABI, the reliability of the ABI can be improved. Alternatively, the cuff of the presently disclosed subject matter can be used in the following manner. The components identical with those of Embodiment 1 re denoted by the same reference numerals, and their detailed description will be omitted.
A cuff 1a of Embodiment 2 is used in breast cancer screening. The cuff 1a of Embodiment 2 is wrapped around the chest 80, and the breasts are pressed at a predetermined pressure by the inflation of the air bag 3.
The circumferential length of the body 2 is adjusted so as to be suitable for the size of the chest of an adult female. The circumferential length of the ultrasonic transmissive portion A is adjusted to a degree at which the portion can cover the breasts when the cuff 1a is attached. Although one ultrasonic transmissive portion A is disposed as shown in
The length of the body 2 in the direction perpendicular to the sheet of
Breast cancer screening using the cuff 1a of Embodiment 2 is performed in the following manner. The cuff 1a is wrapped around the chest 80 of the patient so that the ultrasonic transmissive portion A covers both the breasts, and then fixed in a state where a predetermined circumferential length is set. Next, the air bag 3 is inflated by the pump 11. Since the circumferential length of the cuff 1a is fixed by the fixing portion 4, the chest 80 is pressed, and also the breasts are similarly pressed, with the result that the breasts are deformed to a substantially flat state. In this state, the ultrasonic probe 15 is touched against the breast, and the internal condition of the breast is observed in the echo image displayed on the display device 16, thereby determining whether tumor exist or not.
In breast cancer screening, in order to find tumor, the ultrasonic probe is touched against all regions of the breast, and the internal condition is observed. In the breast, the central and peripheral regions have different thicknesses. When, in the breast, a region having a relatively large thickness is not properly collapsed, therefore, there is a case where an echo image of the region cannot clearly display deep tissue.
By contrast, according to the cuff 1a of Embodiment 2, also an echo image of a breast region having a relatively large thickness is enabled to be clearly displayed so that the condition of internal tissue can be observed, simply by the improvement that, in the cuff having a size which allows the cuff to be wrapped around the chest, the ultrasonic transmissive portion is disposed in accordance with the size of the breasts, and the air bag is adjusted so as not to overlap with the ultrasonic transmissive portion. As the ultrasonic probe which is to be touched against the ultrasonic transmissive portion A, and the like, moreover, related-art devices can be used. When the cuff 1a of Embodiment 2 is used, therefore, breast cancer screening can be easily performed.
As described above, the cuff 1a of Embodiment 2 is configured so that it can be fixed by the fixing portion 4 in a state where the body 2 is wrapped around the chest 80 so as to cover the breasts. When the cuff 1a of Embodiment 2 is used, therefore, breast cancer screening can be easily performed by using a related-art ultrasonic apparatus without necessitating a dedicated apparatus.
Next, Embodiment 3 of the presently disclosed subject matter will be described.
The cuff of Embodiment 1 is attached to a limb region to be used in the blood pressure measurement for measuring the central venous pressure or for calculating the ABI, and the cuff of Embodiment 2 is attached to the chest to be used in breast cancer screening. In addition to above-described uses, the cuff of the presently disclosed subject matter can be used also in the following manner.
The cuff 1b of Embodiment 3 is used in, for example, the diagnosis of an ectopic ureterocele. In the cuff 1b of Embodiment 3, the circumferential length of the body 2 is adjusted so that the body can be wrapped around the abdomen 90. The circumferential length of the ultrasonic transmissive portion A is adjusted to a degree at which a wide region of the abdomen 90 can be observed, and the pressing by the air bag 3 can be sufficiently performed.
Similarly with the above-described embodiments, the circumferential length of the airbag 3 is adjusted to a degree at which the bag does not overlap with the ultrasonic transmissive portion A. The air bag 3 is placed in a region where the pressing is performed when the cuff 1b is attached to the patient as shown in
For example, the lengths of the body 2 and the air bag 3 in the direction perpendicular to the sheet of
As described above, cases were reported in which, in an ultrasonic examination which is performed in the diagnosis of an ectopic ureterocele, when the ultrasonic examination is performed in a state where the hydroureter in the flank is pressed, the ureterocele can be clearly displayed.
Also in the above cases, when the cuff 1b of Embodiment 3 is used, the ectopic ureterocele can be clearly displayed. Namely, the body 2 of the cuff 1b is wrapped around the patient so that the air bag 3 is butted against the hydroureter in the flank, the body is fixed by the fixing portion 4, and the air bag 3 is pressurized to a predetermined pressure by the pump 11 to be inflated. In this state, the ultrasonic probe 15 is butted against the ultrasonic transmissive portion A, and the condition of the bladder is observed on the display device 1. In the pressurization by the air bag 3, a constant pressing force can be stably applied to the flank as compared to the case where the pressurization is performed by the hand. The pressure application on the air bag 3 by the pump 11 can be adjusted while viewing an indicator to check the current pressure, and therefore the pressing force can be accurately adjusted. In the pressing by the cuff, a dedicated apparatus is not used. Therefore, the diagnosis of an ectopic ureterocele or the like can be easily performed simply by the improvement that the ultrasonic transmissive portion is disposed in a related-art cuff, and the air bag is formed so as not overlap with the ultrasonic transmissive portion.
In the cuff 1b of Embodiment 3, as described above, the size is adjusted so that the body 2 is fixed by the fixing portion in the state where the body is wrapped around the abdomen 90 so that the air bag 3 is butted against the hydroureter in the flank. Therefore, the pressing force can be constantly applied as compared to the manual case, and accurately controlled, thereby enabling an ureterocele to be smoothly displayed in the diagnosis of an ectopic ureterocele or the like. Also in the cuff 1b of Embodiment 3, the diagnosis of an ectopic ureterocele or the like can be easily performed without using a dedicated apparatus, simply by the improvement that the ultrasonic transmissive portion is disposed in a related-art cuff, and the air bag is formed so as not overlap with the ultrasonic transmissive portion.
According to an aspect of the presently disclosed subject matter, the ultrasonic transmissive portion through which an ultrasonic wave for observing a tissue in a desired region of the living body is transmissible is provided in the body of the cuff. Therefore, an ultrasonic echo image can be produced, and the state of the tissue under pressure can be observed.
The cuff of the presently disclosed subject matter is wrapped around a desired region of the living body, the ultrasonic transmissive portion is caused to face against an observation region, the body of the cuff is fixed to the desired region of the living body by the fixing portion, and the desired region of the living body is pressurized by the pressurizing portion. Then, the ultrasonic wave irradiated from the ultrasonic probe is caused to transmit through the ultrasonic transmissive portion to impinge on the observation region, thereby enabling a measurement of a blood pressure such as the alternative central venous pressure to be accurately performed.
The cuff of the presently disclosed subject matter has a simple configuration in which the ultrasonic transmissive portion is provided in a related-art cuff. When the cuff of the presently disclosed subject matter is used in, for example, breast cancer screening, therefore, the breast cancer screening can be easily performed by the cuff without introducing a dedicated apparatus.
According to an aspect of the presently disclosed subject matter, the object region can be pressurized with constant force. When it is used in, for example, the diagnosis of an ectopic ureterocele, therefore, the flank can be pressed with constant force by the pressurizing portion. Therefore, a clear image of an ureterocele can be smoothly obtained as compared to the case where the pressurization is performed by the hand.
Number | Date | Country | Kind |
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2011-279712 | Dec 2011 | JP | national |
2012-240825 | Oct 2012 | JP | national |