Medical apparatus

A medical apparatus includes a storing section in which information concerning a drug movement in a living body is stored, an arithmetic processing section that acquires, based on the information stored in the storing section, information concerning a target region to which a first fluorescent drug is administered, information concerning a method of administering the first fluorescent drug, and information indicating start of administration, diagnosis end timing corresponding to the first fluorescent drug and sets, administration start timing of a second fluorescent drug, and a control section that performs control to start the administration of the second fluorescent drug when a current time reaches the administration start timing of the second fluorescent drug and, after the diagnosis end timing corresponding to the first fluorescent drug, performs control to reduce an irradiating light amount of excitation light for exciting the first fluorescent drug.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a medial apparatus and, more particularly, to a medical apparatus capable of performing observation based on fluorescence emitted from a fluorescent drug.

2. Description of the Related Art

In recent years, a cancer diagnosis technique employing a molecular target drug has started to attract attention. Specifically, for example, a method of, after administering a fluorescent drug (a fluorescent probe) targeting living body protein, which specifically develops in a cancer cell, to a living body, determining presence or absence of cancer based on fluorescence emitted in a target region of the living body has been studied in recent years. Such a method is useful in early detection of cancer in a digestive tract field.

As an application of the method, a method of, after administering plural kinds of fluorescent drugs having different fluorescence wavelengths to a living body, complexly observing, based on plural fluorescences emitted in a target region of the living body, development states of plural kinds of living body protein corresponding to the plural kinds of fluorescent drugs is being proposed. Such a method is considered to be useful in, for example, estimation of a stage of cancer, prediction of an infiltration risk of cancer, and prediction of a metastasis risk of cancer.

For example, Japanese Patent Application Laid-Open Publication No. 2006-61683 discloses an endoscope apparatus including a laser beam source that generates excitation light, an endoscope scope including an irradiating section of the excitation light at a distal end portion thereof, an intensifier incorporating CCD that detects fluorescence generated in a subject by the excitation light, fluorescent image generating means for generating a fluorescent image signal based on a fluorescent signal from the intensifier incorporating CCD, distance measuring means for generating a distance signal corresponding to a distance between the irradiating section and the subject, fluorescence amount calculating means for correcting the fluorescent signal with the distance signal and calculating a fluorescence amount not affected by fluctuation in the distance. In the endoscope apparatus, the fluorescence amount calculating means includes time-after-drug-administration correcting means for correcting the fluorescent signal or the fluorescent image signal based on an elapsed time after the fluorescent drug is administered.

The configuration disclosed in Japanese Patent Application Laid-Open Publication No. 2006-61683 makes it possible to correct, even before the influence of the administered fluorescent drug spreads all over the subject, a fluorescent image to a state after the influence of the fluorescent drug spread all over the subject.

SUMMARY OF THE INVENTION

A medical apparatus according to an aspect of the present invention includes: a storing section in which information concerning a drug movement in a living body is stored in advance for each of types of a plurality of fluorescent drugs; an arithmetic processing section that acquires, based on the information stored in the storing section, information concerning a target region of a subject to which a first fluorescent drug is administered, information concerning a method of administering the first fluorescent drug to the target region, and information indicating start of administration of the first fluorescent drug to the subject, information concerning diagnosis start timing and diagnosis end timing corresponding to the first fluorescent drug and sets, based on the diagnosis end timing corresponding to the first fluorescent drug, administration start timing of a second fluorescent drug to the subject; and a control section that performs control to enable the administration of the second fluorescent drug to be started when a current time reaches the administration start timing of the second fluorescent drug to the subject and, after the diagnosis end timing corresponding to the first fluorescent drug, performs control in a state in which an irradiating light amount of excitation light for exciting the first fluorescent drug is set lower than an irradiating light amount of the excitation light in a period from the diagnosis start timing to the diagnosis end timing corresponding to the first fluorescent drug.

A medical apparatus according to another aspect of the present invention includes: a storing section in which information concerning a drug movement in a living body is stored in advance for each of types of a plurality of fluorescent drugs; an arithmetic processing section that acquires, based on the information stored in the storing section, information concerning a target region of a subject to which a first fluorescent drug and a second fluorescent drug are administered, information concerning a method of administering the first fluorescent drug and the second fluorescent drug to the target region, and diagnosis start scheduled timing serving as scheduled timing for starting diagnosis of the target region by both the first fluorescent drug and the second fluorescent drug, first administration start timing for starting administration of the first fluorescent drug to the subject and second administration start timing for starting administration of the second fluorescent drug to the subject; and a control section that performs control to enable the administration of the first fluorescent drug to be started when a current time reaches the first administration start timing, performs control to enable the administration of the second fluorescent drug to be started when the current time reaches the second administration start timing, and, at least until the current time reaches the diagnosis start scheduled timing, performs control for setting irradiation of first excitation light for exciting the first fluorescent drug and second excitation light for exciting the second fluorescent drug in a stopped state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

An embodiment of the present invention is explained below with reference to the drawings.

FIGS. 1 to 30relate to the embodiment of the prevent invention.

FIG. 1is a diagram showing a configuration of a main part of an endoscope system according to the embodiment of the present invention.

An endoscope system301includes, as shown inFIG. 1, a scope2that can be inserted into a body cavity of a subject and picks up an image of a site to be observed201in the body cavity and outputs an image pickup signal, a light source apparatus1that supplies illuminating light for illuminating the site to be observed201observed by the scope2, a processor3that applies various kinds of signal processing to the image pickup signal from the scope2and outputs the image pickup signal; a monitor4including a function of a display section that displays an image corresponding to the output signal from the processor3, a digital filing apparatus5that records an image corresponding to the output signal from the processor3, and a photographing apparatus6that photographs the image corresponding to the output signal from the processor3.

Further, the endoscope system301includes, as shown inFIG. 1, a keyboard62capable of outputting a signal corresponding to key operation such as input operation of a character string to the processor3, a speaker63including a function of a sound output section that emits sound corresponding to the output signal from the processor3, and a dispensing unit71that performs administration of chemical including a fluorescent drug according to the output signal from the processor3.

A light guide13for transmitting illuminating light supplied from the light source apparatus1to a distal end portion of the scope2is inserted through an inside of the scope2. A liquid feeding tube72for administering the chemical, which is supplied from the dispensing unit71, to the site to be observed201is inserted through a not-shown conduit (channel) formed on the inside of the scope2.

The scope2includes, at the distal end portion, an illumination optical system14athat emits the illuminating light, which is transmitted by the light guide13, to the site to be observed201, an objective optical system14bthat focuses return light from the site to be observed201illuminated by the illuminating light, a CCD14of a monochrome type, an image pickup surface of which is arranged in a focusing position of the objective optical system14b, and an image pickup actuator39arranged on an optical path between the objective optical system14band the CCD14. The scope2includes a mode changeover switch15capable of performing operation for switching of an observation mode of the endoscope system301, a release switch16capable of performing operation related to acquisition of a still image of the site to be observed201, and a scope discrimination element17in which peculiar discrimination information corresponding to a type and the like of the scope2is stored.

The CCD14is driven according to control by the processor3and applies photoelectric conversion to the return light from the site to be observed201focused on the image pickup surface to thereby generate an image pickup signal and output the image pickup signal to the processor3. In the CCD14in the present embodiment, a not-shown electronic shutter capable of adjusting an exposure time and a readout time according to control by the processor3is provided. Further, in the CCD14in the present embodiment, a not-shown charge amplifying device is provided.

A detailed configuration of the image pickup actuator39is explained.FIG. 2is a diagram showing a state in the case in which an optical filter is interposed on an optical path in a filter switching mechanism of the image pickup actuator.FIG. 3is a diagram showing a state during energization of a magnet displacement device at the time when the filter switching mechanism is set in the state shown inFIG. 2.FIG. 4is a diagram showing a state in the case in which the optical filter is retracted from the optical path in the filter switching mechanism of the image pickup actuator.FIG. 5is a diagram showing a state during non-energization of the magnet displacement device at the time when the filter switching mechanism is set in the state shown inFIG. 4.

A filter switching device39aof the image pickup actuator39has a configuration capable of switching, according to control by the processor3, a first arrangement state (an interposed state) in which a filter that allows only light in a predetermined wavelength band to pass is interposed on an optical path extending from the objective optical system14bto the CCD14and a second arrangement state (a retracted state) in which the filter that allows only the light in the predetermined wavelength band to pass is retracted from the optical path extending from the objective optical system14bto the CCD14.

Specifically, the filter switching device39aof the image pickup actuator39has a configuration similar to a configuration of a light adjusting device described in Japanese Patent Application Laid-Open Publication No. 2009-8717. In other words, the filter switching device39aincludes a filter switching mechanism101and a magnet displacement device102.

The filter switching mechanism101is formed to hold a filter moving member105, a close-time stopper107, and an open-time stopper108between a lower substrate103and an upper substrate104.

One end of a shape memory alloy wire120is fixed to a magnet119of the magnet displacement device102. A bias spring121and an insulative tube122are inserted through the shape memory alloy wire120. On the other hand, the other end of the shape memory alloy wire120is fixed to a not-shown caulking member. The not-shown caulking member is fixed at an end on an opposite side of the magnet119of the tube122as well.

In the filter moving member105, a rotating shaft109and a columnar magnet110are press fit. An optical filter section118including an optical filter117ais provided in the filter moving member105.

On the other hand, in the lower substrate103, an optical opening111, a rotating shaft insertion hole for inserting the rotating shaft109, and a cutout for guide of the magnet110are formed. In the upper substrate104, as in the lower substrate103, an optical opening having a diameter same as or slightly larger than a diameter of the optical opening111, a rotating shaft insertion hole for inserting the rotating shaft109, and a cutout for guide of the magnet110are formed.

In other words, the rotating shaft109is inserted into the rotating shaft insertion holes respectively provided in the lower substrate103and the upper substrate104. Consequently, the filter moving member105can rotate to be displaced about the rotating shaft109. A rotatable range of the filter moving member105is limited by the close-time stopper107and the open-time stopper108. A movable range of the magnet110is limited by the cutouts for guide respectively provided in the lower substrate103and the upper substrate104.

With the configuration explained above, when the filter moving member105rotates to be displaced about the rotating shaft109, for example, if the optical filter section118comes into contact with the close-time stopper107, a center of the optical filter117aand a center of the optical opening111coincide with each other.

In the first arrangement state (the interposed state) of the filter switching device39a, for example, as shown inFIG. 3, the shape memory alloy wire120contracts according to application of a voltage corresponding to control by the processor3and the magnet119fixed to one end of the shape memory alloy wire120is displaced to a side of the tube122resisting a repulsion force of the bias spring121, whereby an N pole of the magnet110and an N pole of the magnet119are arranged in opposed positions.

Consequently, in the first arrangement state (the interposed state), a repulsive force is generated between the magnet110and the magnet119and the magnet110is displaced toward a center direction of the filter switching mechanism101. As a result, in the first arrangement state (the interposed state), for example, as shown inFIG. 2, the filter moving member105rotates counterclockwise about the rotating shaft109and the optical filter section118comes into contact with the close-time stopper107.

In the first arrangement state (the interposed state), since the optical opening111is covered by the optical filter section118, the filter switching mechanism101allows only return light in a predetermined wavelength band specified by the optical filter117ato pass to the image pickup surface of the CCD14.

On the other hand, with the configuration explained above, when the filter moving member105rotates to be displaced about the rotating shaft109, for example, if the optical filter section118comes into contact with the open-time stopper108, the optical filter section118completely retracts from the optical opening111.

In the second arrangement state (the retracted state) of the filter switching device39a, for example, as shown inFIG. 5, the shape memory alloy wire120expands according to application of a voltage corresponding to control by the processor3and the magnet119fixed to one end of the shape memory alloy wire120is displaced to an opposite side of the tube122following the repulsion force of the bias spring121, whereby an S pole of the magnet110and the N pole of the magnet119are arranged in opposed positions.

Consequently, in the second arrangement state (the retracted state), an attractive force is generated between the magnet110and the magnet119and the magnet110is displaced toward an outer circumferential direction of the filter switching mechanism101. As a result, in the second arrangement state (the retracted state), for example, as shown inFIG. 4, the filter moving member105rotates clockwise about the rotating shaft109and the optical filter section118comes into contact with the open-time stopper108.

In the second arrangement state (the retracted state), since the optical opening111is not covered by the optical filter section118, the filter switching mechanism101does not perform band limitation to return light passed through the objective optical system14band allows the return light to directly pass to the image pickup surface of the CCD14.

FIG. 6is a diagram showing characteristics of an optical filter provided in the image pickup actuator.

It is assumed that the optical filter117aof the filter switching device39ain the present embodiment is formed to allow only light of 680 to 850 nm to pass without generally attenuating the light, for example, as shown inFIG. 6.

The image pickup actuator39in the present embodiment includes, as shown inFIG. 1, the filter switching device39aand a filter switching device39bhaving a configuration substantially the same as the configuration of the filter switching device39a.

FIG. 7is a diagram showing characteristics of an optical filter, which is different from the optical filter shown inFIG. 6, provided in the image pickup actuator.

The filter switching device39bincludes an optical filter117bthat allows only return light in a wavelength band different from the return light in the optical filter117aallowed to pass by the optical filter117ato pass. On the other hand, the filter switching device39bincludes components same as the components of the filter switching device39aother than the optical filter117b. Further, the optical filter117bis formed to allow only light of 790 to 850 nm to pass without generally attenuating the light, for example, as shown inFIG. 7.

The image pickup actuator39in the present embodiment is not limited to the image pickup actuator configured based on the configuration of the light adjusting device described in Japanese Patent Application Laid-Open Publication No. 2009-8717 explained above. Specifically, as long as the image pickup actuator39in the present embodiment has a configuration capable of switching the first arrangement state (the interposed state) and the second arrangement state (the retracted state) concerning each of the optical filters117aand117b, the image pickup actuator39may be configured based on another configuration such as the light adjusting device described in Japanese Patent Application Laid-Open Publication No. 2009-8719.

The light source apparatus1includes a lamp7that emits light in a wavelength range including a visible range and a near infrared range, a filter wheel8provided to vertically traverse an optical path of the lamp7, a motor9that switches a filter interposed on the optical path of the lamp7to one of filters of the filter wheel8, a rotating filter10provided to vertically traverse the optical path of the lamp7, a motor11that drives to rotate the rotating filter10, a diaphragm12arranged on the optical path of the lamp7from the filter wheel8to the rotating filter10, and a condensing lens12athat condenses illuminating light passed through the rotating filter10on an end face on a light incident side of the light guide13.

FIG. 8is a diagram showing an example of a configuration of the filter wheel provided in the light source apparatus.

As shown inFIG. 8, in the filter wheel8having a disk shape, a normal light filter50that allows light in the visible range to pass, a first excitation light filter51that allows light in a part of the visible range and in a red range to pass, a second excitation light filter55that allows light in a part of the visible range and in the near infrared range to pass, and a third excitation light filter56having both pass bands of the first excitation light filter51and the second excitation light filter55are provided along a circumferential direction of the disk. In other words, the filter wheel8is configured such that the motor9rotates according to control by the processor3, whereby any one of the normal light filter50, the first excitation light filter51, the second excitation light filter55, and the third excitation light filter56is interposed on the optical path of the lamp7and the other three filters than the one filter are retracted from the optical path of the lamp7.

FIG. 9is a diagram showing characteristics of the normal light filter provided in the filter wheel.

The normal light filter50is formed to allow light in a wavelength band of 400 to 650 nm among lights in wavelength bands emitted from the lamp7to pass without generally attenuating the light as shown inFIG. 9.

FIG. 10is a diagram showing characteristics of the first excitation light filter provided in the filter wheel.

The first excitation light filter51is formed to allow light in a wavelength band of 600 to 650 nm among the lights in the respective wavelength bands emitted from the lamp7to pass without generally attenuating the light and allow light in a wavelength band of 790 to 810 nm to pass while attenuating the light to predetermined intensity as shown inFIG. 10.

FIG. 11is a diagram showing characteristics of the second excitation light filter provided in the filter wheel.

The second excitation light filter55is formed to allow light in a wavelength band of 700 to 760 nm among the lights in the respective wavelength bands emitted from the lamp7to pass without generally attenuating the light and allow light in the wavelength band of 790 to 810 nm to pass while attenuating the light to predetermined intensity as shown inFIG. 11.

FIG. 12is a diagram showing characteristics of the third excitation light filter provided in the filter wheel.

The third excitation light filter56is formed to allow light in the wavelength band of 600 to 760 nm among the lights in the respective wavelength bands emitted from the lamp7to pass without generally attenuating the light and allow light in the wavelength band of 790 to 810 nm to pass while attenuating the light to predetermined intensity as shown inFIG. 12.

The diaphragm12has a configuration capable of increasing and reducing a light amount of light passed through the filter wheel8according to control by the processor3.

FIG. 13is a diagram showing an example of a configuration of the rotating filter provided in the light source apparatus.

As shown inFIG. 13, in the rotating filter10having disk shape, an optical filter41that allows light in the red range to pass, an optical filter42that allows light in a green range to pass, and an optical filter43that allows light in a blue range and the near infrared range to pass are provided along a circumferential direction of the disk. In other words, the rotating filter10is configured such that the motor11rotates according to control by the processor3(a timing signal of a below-mentioned timing generator30), whereby the optical filters41,42, and43are interposed on the optical path of the lamp7or retracted from the optical path of the lamp7while being sequentially interchanged. It is assumed that the rotating filter10in the present embodiment is formed not to allow light to pass when a place other than places where the optical filters41,42, and43are arranged is interposed on the optical path of the lamp7.

FIG. 14is a diagram showing characteristics of the optical filter provided in the rotating filter.

The optical filter41is formed to allow light in the wavelength band of 600 to 650 nm among wavelength bands of light passed through the filter wheel8and the diaphragm12to pass without generally attenuating the light as shown inFIG. 14.

FIG. 15is a diagram showing characteristics of an optical filter, which is different from the optical filter shown inFIG. 14, provided in the rotating filter.

The optical filter42is formed to allow light in the wavelength band of 500 to 600 nm and light in the wavelength band of 790 to 810 nm among the respective wavelength bands of light passed through the filter wheel8and the diaphragm12to pass without generally attenuating the lights as shown inFIG. 15.

FIG. 16is a diagram showing characteristics of an optical filter, which is different from the optical filters shown inFIGS. 14 and 15, provided in the rotating filter.

The optical filter43is formed to allow light in the wavelength band of 400 to 500 nm and light in the wavelength band of 700 to 760 nm among the respective wavelength bands of light passed through the filter wheel8and the diaphragm12to pass as shown inFIG. 16.

After being inputted to the processor3, the image pickup signal outputted from the CCD14is subjected to processing such as CDS (correlated double sampling) in a pre-process circuit18and, after being converted into a digital image signal in an A/D conversion circuit19, outputted to a color balance correction circuit20.

The color balance correction circuit20selects, based on the timing signal from the timing generator30, a color balance correction coefficient corresponding to each of the optical filters41,42, and43to be synchronized with timing when the optical filters41,42, and43of the rotating filter10are sequentially interposed on the optical path of the lamp7and reads the selected color balance correction coefficient from a not-shown memory. After multiplying image signals sequentially outputted from the A/D conversion circuit19with the color balance correction coefficient read from the not-shown memory, the color balance correction circuit20outputs the image signal after the multiplication to the multiplexer21.

The color balance correction coefficient is a correction value calculated by arithmetic processing of the control section33(an arithmetic processing circuit33a) in a color balance operation for a white balance or the like. The color balance correction coefficient is stored in the not-shown memory of the color balance correction circuit20as a processing result of the arithmetic processing. The color balance operation for the white balance or the like is started at timing when the control section33detects that operation related to execution start of the color balance operation is performed in a color balance setting switch (not shown in the figures) provided in an input switch group60of the processor3.

The multiplexer21outputs, based on the timing signal from the timing generator30, image signals outputted from the color balance correction circuit20while appropriately allocating the image signals to synchronization memories22a,22b, and22cto be synchronized with the timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7.

The synchronization memories22a,22b, and22chave a configuration capable of temporarily storing an image signal outputted from the multiplexer21.

After simultaneously reading the image signals stored in the synchronization memories22a,22b, and22c, the image processing circuit23applies predetermined image processing to the read three image signals. The image processing circuit23outputs the three image signals after the predetermined image processing to the color tone adjusting circuit24while allocating the image signals to a first color channel corresponding to a first color component (e.g., a red (R) component), a second color channel corresponding to a second color component (e.g., a green (G) component), and a third color channel corresponding to a third color component (e.g., a blue (B) component).

After reading a color tone adjustment coefficient stored in a not-shown memory, the color tone adjusting circuit24performs matrix arithmetic processing using the color tone adjustment coefficient and the image signal of the first color component (the first color channel), the image signal of the second color component (the second color channel), and the image signal of the third color component (the third color channel) outputted from the image processing circuit23. Thereafter, the color tone adjusting circuit24applies gamma correction processing to the image signal of the first color component, the image signal of the second color component, and the image signal of the third color component subjected to the matrix arithmetic processing. The color tone adjusting circuit24outputs the image signals of the first color component, the second color component, and the third color component subjected to the gamma correction processing to an encoding circuit26and a light adjustment circuit27. The color tone adjusting circuit24outputs the image signal of the first color component subjected to the gamma correction processing to a D/A conversion circuit25a, outputs the image signal of the second color component subjected to the gamma correction processing to a D/A conversion circuit25b, and outputs the image signal of the third color component subjected to the gamma correction processing to a D/A conversion circuit25c.

The color tone adjustment coefficient is an adjustment value calculated by arithmetic processing by the control section33(the arithmetic processing circuit33a) in a color tone adjustment operation. The color tone adjustment coefficient is stored in the not-shown memory of the color tone adjusting circuit24as a processing result of the arithmetic processing. The color tone adjustment operation is started at timing when the control section33detects that operation related to a change of a color tone displayed on the monitor4is performed in a color tone setting switch (not shown in the figures) provided in the input switch group60of the processor3. When the operation related to a change of a color tone displayed on the monitor4is performed, the control section33(the arithmetic processing circuit33a) performs arithmetic processing for calculating a color tone adjustment coefficient corresponding to the color tone after the change.

The image signals of the first color component, the second color component, and the third color component outputted from the color tone adjusting circuit24are outputted to the monitor4after being respectively converted into analog video signals in the D/A conversion circuits25a,25b, and25c. Consequently, the monitor4displays observed images corresponding to respective observation modes.

The image signals of the first color component, the second color component, and the third color component outputted from the color tone adjusting circuit24are outputted to the digital filing apparatus5and the photographing apparatus6after being subjected to encoding processing in the encoding circuit26. Consequently, the digital filing apparatus5records and stores still image at the time when the control section33detects input operation in the release switch16. The photographing apparatus6photographs the still image at the time when the control section33detects the input operation in the release switch16.

The light adjustment circuit27performs control for the diaphragm12based on respective signal levels of the image signals of the first color component, the second color component, and the third color component outputted from the color tone adjusting circuit24such that illuminating light of an appropriate light amount corresponding to an observation mode is supplied from the light source apparatus1. The light adjustment circuit27performs control for changing an amplification ratio of an amplification ratio control circuit29.

An exposure time control circuit28controls the electronic shutter of the CCD14based on the timing signal outputted from the timing generator30and an output signal from the control section33to be synchronized with the timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7and to correspond to the output signal from the control section33. An exposure time in the CCD14is changed by such control for the electronic shutter.

The amplification ratio control circuit29controls the charge amplifying device of the CCD14based on the control by the light adjustment circuit27and the timing signal outputted from the timing generator30to obtain an amplification ratio synchronized with the timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7and corresponding to the control by the light adjustment circuit27. The amplification ratio in the CCD14is changed by such control for the charge amplifying device.

The timing generator30generates a timing signal for appropriately synchronizing operations of the respective sections of the endoscope system301and outputs the timing signal.

A CCD driver31drives the CCD14based on the timing signal outputted from the timing generator30to be synchronized with the timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7.

An image pickup actuator control circuit32applies, to the image pickup actuator39, based on the timing signal outputted from the timing generator30, control for synchronizing the timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7, switching timing for an arrangement state of the optical filter117ain the filter switching device39a, and switching timing of an arrangement state of the optical filter117bin the filter switching device39b.

The control section33including a CPU and a memory includes the arithmetic processing circuit33athat performs arithmetic processing, a storing circuit33b, a timing circuit33c, a determination circuit33d, and a switching control circuit33e.

In the storing circuit33b, various data used for, for example, the arithmetic processing of the arithmetic processing circuit33asuch as below-mentioned table data are stored in the storing circuit33b.

The timing circuit33cincludes an RTC (real time clock) and a timer. The timing circuit33cis configured such that an elapsed time from administration of a fluorescent drug to a subject can be measured for each of fluorescent drugs.

The determination circuit33dperforms below-mentioned determination processing based on an arithmetic processing result of the arithmetic processing circuit33aand a measurement result of the timing circuit33c.

The switching control circuit33eapplies, to the motor9of the light source apparatus1and the like, control based on a detection result of an operation state in the mode changeover switch15of the scope2connected to the processor3and a determination result of the determination circuit33d.

On the other hand, in the input switch group60of the processor3, plural switches such as a color tone setting switch capable of performing operation concerning a change of a color tone of an image displayed on the monitor4, a color balance setting switch capable of performing operation concerning a color balance operation for a white balance or the like, and an image display selecting switch capable of performing operation concerning switching of a display form of an observed image displayed on the monitor4are provided. The control section33detects operation states of the respective switches provided in the input switch group60of the processor3and performs control, processing, and the like corresponding to a detection result.

The control section33detects an operation state in the release switch16of the scope2connected to the processor3and performs, according to a detection result, control related to recording of a still image in the digital filing apparatus5and (or) photographing of the still image in the photographing apparatus6.

When the scope2is connected to the processor3, the control section33reads information stored in the scope discrimination element17and performs control corresponding to the read information.

It is assumed that the control section33in the present embodiment is connected to the respective sections of the processor3via a not-shown signal line or the like to be capable of applying comprehensive control to the respective sections of the processor3.

A notification signal generating circuit61generates a character signal for displaying a predetermined character string capable of notifying information concerning determination results of the determination circuit33dof the control section33and outputs the character signal to the monitor4. The notification signal generating circuit61generates a sound signal for generating predetermined sound capable of notifying the information concerning the determination results of the determination circuit33dof the control section33and outputs the sound signal to the speaker63. The notification signal generating circuit61in the present embodiment only has to be configured to be capable of outputting at least one of the character signal and the sound signal.

A valve control circuit64generates, based on control by the control section33, a valve switching signal for switching open and close of a below-mentioned valve section71cprovided in the dispensing unit71and outputs the valve switching signal.

FIG. 17is a diagram showing an example of a configuration of the dispensing unit.

The dispensing unit71includes, as shown inFIG. 17, a chemical tank71ain which a chemical containing a fluorescent drug is stored in advance, a tubular member71bconnected to an opening of the chemical tank71a, and a valve section71cprovided between the tubular member71band the liquid feeding tube72.

The valve section71cincludes a valve member such as an electromagnetic valve. The valve section71cperforms an opening and closing operation according to a valve switching signal outputted from the processor3to thereby start or stop supply of the chemical from the tubular member71bto the liquid feeding tube72.

Subsequently, action of the endoscope system301in the present embodiment is explained. In an example explained in the present embodiment, a first fluorescent drug excited by irradiation of light in the wavelength band of 600 to 650 nm to emit fluorescence in a first wavelength band (680 to 750 nm) and a second fluorescent drug excited by irradiation of light in the wavelength band of 700 to 760 nm to emit fluorescence in a second wavelength band (790 to 850 nm) are administered to the same subject and observation is performed. It is assumed that, in the chemical tank71aof the dispensing unit71, a chemical including the second fluorescent drug is stored in advance.

First, a surgeon or the like connects the respective sections of the endoscope system301and turns on a power supply to thereby start operations of the respective sections.

According to turn-on of a power supply for the processor3, output of a timing signal from the timing generator30is started.

FIG. 18is a timing chart showing an exposure period and a readout period of the CCD provided in the scope.

The CCD driver31drives the CCD14based on the timing signal from the timing generator30according to, for example, the timing chart ofFIG. 18. Consequently, the CCD14operates such that an exposure period T1serving as a period related to accumulation of charges and a readout period T2serving as a period related to flushing of the charges accumulated in the exposure period T1are alternately interchanged.

FIG. 19is a timing chart showing interposing actions and retracting actions for the respective optical filters involved in the rotation of the rotating filter.

According to turn-on of a power supply for the light source apparatus1and start of an output of the timing signal from the timing generator30, rotation driving of the motor11is started. According to the rotation driving of the motor11, the optical filters41,42, and43are interposed on the optical path of the lamp7or retracted from the optical path of the lamp7while being sequentially interchanged. The interposing actions and the retracting actions of the optical filters41,42, and43involved in the rotation driving of the motor11are performed according to, for example, timing corresponding to the timing chart ofFIG. 19. Specifically, the motor11rotates the rotating filter10to sequentially interpose the optical filters41,42, and43on the optical path of the lamp7in the exposure period of the CCD14and retract the optical filters41,42, and43from the optical path of the lamp7in the readout period of the CCD14.

On the other hand, after connecting the respective sections of the endoscope system301and turning on the power supply, the surgeon or the like operates the keyboard62to thereby (cause the monitor4to display, for example, a setting screen related to various kinds of setting for the processor3and) set a reference value Ns of an accumulation amount at diagnosis start time and a reference value Ne of an accumulation amount at diagnosis end time in observation performed using a fluorescent drug. The surgeon or the like administers the first fluorescent drug to the site to be observed201of the subject at any point before or after setting the reference values Ns and Ne.

The reference values Ns and Ne are values indicating a ratio with respect to 100% set as a maximum value Nmax equivalent to a peak value of an accumulation amount of the fluorescent drug. In an initial state, the reference values Ns and Ne are stored in the storing circuit33bin a state in which the reference values Ns and Ne are set as Ns=Ne=Nmax.

Depending on a way of combining a type of a fluorescent drug in use, an organ to which a target region (the site to be observed201) administered with the fluorescent drug belongs, and a method of administering the fluorescent drug to the target region, a sufficient diagnosis ability can be sometimes obtained even if the reference values Ns and Ne are respectively values other than Nmax. Therefore, the reference values Ns and Ne may be able to be respectively set to arbitrary values by the operation of the keyboard62or may be able to be selected one by one out of predetermined plural values (such as 80%, 60%, and the like).

When the control section33detects that new reference values Ns and Ne are set by operation of the keyboard62, the control section33updates the reference values Ns and Ne stored in the storing circuit33b.

After performing the setting of the reference values Ns and Ne, the surgeon or the like operates the keyboard62to thereby input various kinds of information such as a type of the first fluorescent drug, an organ to which a target region (the site to be observed201) administered with the first fluorescent drug belongs, a method of administering the first fluorescent drug to the target region, and an administration start time of the first fluorescent drug to the subject.

After performing the setting of the reference values Ns and Ne, the surgeon or the like operates the keyboard62to thereby input various kinds of information such as a type of the second fluorescent drug, an organ to which a target region (the site to be observed201) administered with the second fluorescent drug belongs, and a method of administering the second fluorescent drug to the target region.

On the other hand, the arithmetic processing circuit33aof the control section33selects, out of the table data stored in advance in the storing circuit33b, table data coinciding with the type of the first fluorescent drug and table data coinciding with the type of the second fluorescent drug.

FIG. 20is a diagram showing an example of table data used in selecting a drug movement of a fluorescent drug.

In the table data, for example, as shown inFIG. 20, information concerning drug movements in a living body is stored in advance in the storing circuit33bin a state in which the information is classified for each of types of plural fluorescent drugs. According to the information, the arithmetic processing circuit33aof the control section33selects the table data illustrated inFIG. 20when a fluorescent drug in use is a fluorescent drug A.

Further, the arithmetic processing circuit33aof the control section33selects, out of the table data coinciding with the type of the first fluorescent drug, one drug movement corresponding to a combination of an organ to which a target region (the site to be observed201) administered with the first fluorescent drug belongs and a method of administering the first fluorescent drug to the target region. The arithmetic processing circuit33aof the control section33selects, out of the table data coinciding with the type of the second fluorescent drug, one drug movement corresponding to a combination of an organ to which a target region (the site to be observed201) administered with the second fluorescent drug belongs and a method of administering the second fluorescent drug to the target region.

Specifically, for example, when a target region (the site to be observed201) administered with the fluorescent drug A belong to a stomach and the fluorescent drug A is administered by intravenous injection in the table data of the fluorescent drug A shown inFIG. 20, the arithmetic processing circuit33aof the control section33selects a drug movement A02.

According to the present embodiment, for example, the reference values Ns and Ne are set in advance for each of the drug movements in the respective table data stored in the storing circuit33b, whereby the reference values Ns and Ne may be uniquely decided according to selection of one drug movement.

The arithmetic processing circuit33aof the control section33causes, based on the reference values Ns and Ne stored in the storing circuit33band an administration start time of the first fluorescent drug to the subject, a point when the elapsed time T from the administration of the first fluorescent drug to the subject is 0 and the accumulation amount N of the fluorescent drug is 0 to coincide with the administration start time in one drug movement selected out of the table data coinciding with the type of the first fluorescent drug, acquires a diagnosis start time Ts1equivalent to the first elapsed time T when the accumulation amount N is equal to Ns, and acquires a diagnosis end time Te1equivalent to the elapsed time T when the accumulation amount N is equal to Ne last after the diagnosis start time Ts1.

The arithmetic processing circuit33aof the control section33causes a point when the elapsed time T from the administration of the second fluorescent drug to the subject is 0 and the accumulation amount N of the fluorescent drug is 0 to coincide (generally coincide) with the administration end time Te1in one drug movement selected out of the table data coinciding with the type of the second fluorescent drug. In other words, the arithmetic processing circuit33aof the control section33sets an administration start time of the second fluorescent drug to the subject based on the diagnosis end time Te1of the first fluorescent drug.

Further, the arithmetic processing circuit33aof the control section33acquires a diagnosis start time Ts2equivalent to the first elapsed time T when the accumulation amount N is equal to Ns and acquires a diagnosis end time Te2equivalent to the elapsed time T when the accumulation amount N is equal to Ne last after the diagnosis start time Ts2.

FIG. 21is a diagram showing an example of the one drug movement selected out of the table data coinciding with the type of the first fluorescent drug.FIG. 22is a diagram showing an example of the one drug movement selected out of the table data coinciding with the type of the second fluorescent drug.FIG. 23is a diagram showing an example of diagnosis start times and diagnosis end times acquired when the drug movements shown inFIGS. 21 and 22are respectively selected.

A drug movement of a fluorescent drug in a living body has a correlation shown inFIGS. 21 and 22between the elapsed time T from administration of the fluorescent drug into a body of the subject until the fluorescent drug is discharged and the accumulation amount N in a target region (the site to be observed201) in the body of the subject administered with the fluorescent drug. Therefore, for example, when the drug movement shown inFIG. 21is selected as a drug movement of the first fluorescent drug and the reference values Ns and Ne are set equal, the diagnosis start time Ts1and the diagnosis end time Te1shown inFIG. 23are acquired. As shown inFIG. 23, the diagnosis end time Te1of the first fluorescent drug is adjusted to an administration start time of the second fluorescent drug.

For example, when the drug movement shown inFIG. 22is selected as a drug movement of the second fluorescent drug and the reference values Ns and Ne are set equal, the diagnosis start time Ts2and the diagnosis end time Te2shown inFIG. 23are acquired.

When the first fluorescent drug is directly sprayed and administered to the target region, unlike the administration by the intravenous injection, a time immediately after the first fluorescent drug is actually sprayed to the target region is equivalent to an administration start time to the subject, i.e., time when the elapsed time T is 0 and the accumulation amount N of the fluorescent drug is 0. In view of such a point, when the first fluorescent drug is directly sprayed and administered to the target region, the time equivalent to time when the elapsed time T is 0 and the accumulation amount N of the fluorescent drug is 0 is set to, for example, time when an administration start time notice switch (not shown in the figures) provided in the input switch group60is depressed rather than an administration start time inputted by operation of the keyboard62. Consequently, it is possible to acquire an accurate diagnosis start time Ts1and an accurate diagnosis end time Te1.

On the other hand, the determination circuit33dof the control section33performs, based on the diagnosis start time Ts1and the diagnosis end time Te1acquired by the arithmetic processing circuit33aand a measuring result of the timing circuit33c, determination concerning whether a current time is equivalent to time within a diagnosis available time of the first fluorescent drug, which is a period of time from the diagnosis start time Ts1to the diagnosis end time Te1. The determination circuit33dof the control section33performs, based on the diagnosis start time Ts2and the diagnosis end time Te2acquired by the arithmetic processing circuit33aand the measuring result of the timing circuit33c, determination concerning whether the current time is equivalent to time within a diagnosis available time of the second fluorescent drug, which is a period of time from the diagnosis start time Ts2to the diagnosis end time Te2.

In other words, the determination circuit33dof the control section33is configured to be capable of performing, based on the diagnosis start time Ts1and the diagnosis end time Te1acquired by the arithmetic processing circuit33aand the measuring result of the timing circuit33c, determination whether the current time reaches the diagnosis start time Ts1and determination whether the current time reaches the diagnosis end time Te1. The determination circuit33dof the control section33is configured to be capable of performing, based on the diagnosis start time Ts2and the diagnosis end time Te2acquired by the arithmetic processing circuit33aand the measuring result of the timing circuit33c, determination whether the current time reaches the diagnosis start time Ts2and determination whether the current time reaches the diagnosis end time Te2.

For example, an operation performed in switching of an observation mode in the endoscope system301in the present embodiment is explained with reference to an example in the case in which the diagnosis start time Ts1, the diagnosis end time Te1, the diagnosis start time Ts2, and the diagnosis end time Te2illustrated inFIG. 23are acquired.

When a determination result that the current time does not reach the diagnosis start time Ts1of the first fluorescent drug (T<Ts1) is obtained by the determination circuit33d, the switching control circuit33eof the control section33applies, irrespective of an operation state of the mode changeover switch15, control for switching the observation mode to a below-described white color light observation mode to the motor9and the image pickup actuator control circuit32.

On the other hand, when a determination result that the current time is within the diagnosis available time of the first fluorescent drug (Ts1≦T≦Te1) is obtained by the determination circuit33d, the switching control circuit33eof the control section33interposes the first excitation light filter51on the optical path of the lamp7by controlling the motor9of the light source apparatus1when switching operation to a first observation mode for irradiating excitation light corresponding to the first fluorescent drug is performed in the mode changeover switch15(or when switching from the below-described white color light observation mode to the first observation mode is performed irrespective of an operation state of the mode changeover switch15). In other words, in the first observation mode, frame-sequential first illuminating light including reference light in the wavelength band of 790 to 810 nm and first excitation light in the wavelength band of 600 to 650 nm is supplied to the light guide13.

Further, when the determination result that the current time is within the diagnosis available time of the first fluorescent drug is obtained by the determination circuit33d, the switching control circuit33eof the control section33controls the image pickup actuator control circuit32when switching operation to the first observation mode is performed in the mode changeover switch15(or when switching from the below-mentioned white color light observation mode to the first observation mode is performed irrespective of an operation state of the mode changeover switch15). By controlling the image pickup actuator control circuit32, the switching control circuit33eof the control section33causes the image pickup actuator39to operate to synchronize timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7and switching timing of an arrangement state of the optical filter117ain the filter switching device39a.

FIG. 24is a timing chart showing interposing actions and retracting actions in the first observation mode for the respective optical filters provided in the image pickup actuator.

Specifically, as shown inFIGS. 18,19, and24, in the first observation mode, in the exposure period of the CCD14and a period in which the optical filter41is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the first arrangement state (the interposed state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the second arrangement state (the retracted state). On the other hand, as shown inFIGS. 18,19, and24, in the first observation mode, in the readout period of the CCD14, a period in which the optical filter42is interposed on the optical path of the lamp7, or a period in which the optical filter43is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the second arrangement state (the retracted state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the second arrangement state (the retracted state).

Therefore, in the first observation mode, the first fluorescent drug is excited by the first illuminating light (the first excitation light) emitted from the light guide13. Therefore, first fluorescence in the wavelength band of 680 to 750 nm and reference light in the wavelength band of 790 to 810 nm are sequentially focused on the image pickup surface of the CCD14as return light from the site to be observed201.

When a determination result that the current time is not within the diagnosis available time of the first fluorescent drug (does not reach the diagnosis start time Ts1or exceeds the diagnosis end time Te1) is obtained by the determination circuit33d, even if switching operation from another observation mode to the first observation mode is performed in the mode changeover switch15, the switching control circuit33eof the control section33invalidates the switching operation by maintaining a control state for the motor9and the image pickup actuator control circuit32in a state before the switching operation is performed.

At a point when the determination result that the current time is within the diagnosis available time of the first fluorescent drug is obtained by the determination circuit33d, i.e., a point when the current time reaches the diagnosis start time Ts1of the first fluorescent drug, the switching control circuit33eof the control section33may apply control for shifting the observation mode to the first observation mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15.

Further, the switching control circuit33eof the control section33controls, based on a determination result of the determination circuit33d, the valve control circuit64at timing when the current time reaches the diagnosis end time Te1of the first fluorescent drug to thereby start administration of the chemical including the second fluorescent drug to the site to be observed201. According to such control of the switching control circuit33e, the valve control circuit64sets the valve section71cof the dispensing unit71in an open state for a fixed period, whereby the chemical including the second fluorescent drug is administered to the site to be observed201by an amount necessary for fluorescence observation. According to the present embodiment, the switching control circuit33emay have a configuration in which, after the current time reaches the diagnosis end time Te1of the first fluorescent drug, for example, an administration start switch (not shown in the figures) provided in the input switch group60is depressed, whereby control by the valve control circuit64is started. With such a configuration, the surgeon or the like can perform administration of a fluorescent drug to a target region highly accurately (at suitable timing).

On the other hand, when the determination result that the current time is not within the diagnosis available time of the first fluorescent drug is obtained by the determination circuit33d, the notification signal generating circuit61generates a character signal for displaying a character string for informing a period of time when switching to the first observation mode is impossible including a message that, for example, the current time does not reach the diagnosis start time Ts1of the first fluorescent drug or the current time exceeds the diagnosis end time Te1of the first fluorescent drug and outputs the character signal to the monitor4. When the determination result that the current time is not within the diagnosis available time of the first fluorescent drug is obtained by the determination circuit33d, the notification signal generating circuit61generates a sound signal for generating sound for informing the period of time when switching to the first observation mode is impossible including the message that, for example, the current time does not reach the diagnosis start time Ts1of the first fluorescent drug or the current time exceeds the diagnosis end time Te1of the first fluorescent drug and outputs the sound signal to the speaker63.

The notification signal generating circuit61may operate to perform the respective notifications at a point when the current time reaches the diagnosis start time Ts1and the diagnosis end time Te1of the first fluorescent drug or operate to cause the monitor4to always display the diagnosis start time Ts1and the diagnosis end time Te1of the first fluorescent drug based on a determination result of the determination circuit33d.

Further, the notification signal generating circuit61may operate to cause the monitor4to display a message for urging administration of the second fluorescent drug and (or) cause the speaker63to output sound at a point when the current time reaches the diagnosis end time Te1based on a determination result of the determination circuit33d. The notification signal generating circuit61performs such an operation, whereby, as an administering method for the second fluorescent drug, it is also possible to adopt an administering method other than a method of administering the second fluorescent drug using the dispensing unit71such as oral administration or intravenous injection administration.

When a determination result that the current time exceeds the diagnosis end time Te1of the first fluorescent drug and does not reach the diagnosis start time Ts2of the second fluorescent drug (Te1<T<Ts2) is obtained by the determination circuit33d, the switching control circuit33eof the control section33applies control for switching the observation mode to the below-described white color light observation mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15. In other words, the switching control circuit33eof the control section33stops the irradiation of the first illuminating light (the first excitation light) on the site to be observed201(reduces an irradiating light amount of the first illuminating light (the first excitation light) to 0) at timing when the current time exceeds the diagnosis end time Te1of the first fluorescent drug.

When the determination result that the current time exceeds the diagnosis end time Te1of the first fluorescent drug and does not reach the diagnosis start time Ts2of the second fluorescent drug is obtained by the determination circuit33d, (the switching control circuit33eof) the control section33of the present embodiment may perform, for example, control for supplying a physiological salt solution stored in advance in a not-shown tank or the like to the site to be observed201. With such a configuration of (the switching control circuit33eof) the control section33, it is possible to clean the site to be observed201before observation in the below-described second observation mode is started.

When the determination result that the current time exceeds the diagnosis end time Te1of the first fluorescent drug and does not reach the diagnosis start time Ts2of the second fluorescent drug is obtained by the determination circuit33d, (the switching control circuit33eof) the control section33of the present embodiment does not always apply the control for switching the observation mode to the below-described white color light observation mode to the motor9and the image pickup actuator control circuit32. (The switching control circuit33eof) The control section33may perform, for example, control for reducing an irradiating light amount of the first excitation light to be smaller than an irradiating light amount within the diagnosis available time of the first fluorescent drug while maintaining the first observation mode.

On the other hand, when a determination result that the current time is within the diagnosis available time of the second fluorescent drug (Ts2≦T≦Te2) is obtained by the determination circuit33d, the switching control circuit33eof the control section33interposes the second excitation light filter55on the optical path of the lamp7by controlling the motor9of the light source apparatus1when switching operation to a second observation mode for irradiating excitation light corresponding to the second fluorescent drug is performed in the mode changeover switch15(or when switching from the below-described white color light observation mode to the second observation mode is performed irrespective of an operation state of the mode changeover switch15). In other words, in the second observation mode, frame-sequential second illuminating light including reference light in the wavelength band of 790 to 810 nm and second excitation light in the wavelength band of 700 to 760 nm is supplied to the light guide13.

Further, when the determination result that the current time is within the diagnosis available time of the second fluorescent drug is obtained by the determination circuit33d, the switching control circuit33eof the control section33controls the image pickup actuator control circuit32when switching operation to the second observation mode is performed in the mode changeover switch15(or when switching from the below-mentioned white color light observation mode to the second observation mode is performed irrespective of an operation state of the mode changeover switch15). By controlling the image pickup actuator control circuit32, the switching control circuit33eof the control section33causes the image pickup actuator39to operate to synchronize timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7and switching timing of an arrangement state of the optical filter117bin the filter switching device39b.

FIG. 25is a timing chart showing interposing actions and retracting actions in the second observation mode for the respective optical filters provided in the image pickup actuator.

Specifically, as shown inFIGS. 18,19, and25, in the second observation mode, in the exposure period of the CCD14and a period in which the optical filter43is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the second arrangement state (the retracted state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the first arrangement state (the interposed state). On the other hand, as shown inFIGS. 18,19, and25, in the second observation mode, in the readout period of the CCD14, a period in which the optical filter41is interposed on the optical path of the lamp7, or the optical filter42is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the second arrangement state (the retracted state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the second arrangement state (the retracted state).

Therefore, in the second observation mode, the second fluorescent drug is excited by the second illuminating light (the second excitation light) emitted from the light guide13. Therefore, second fluorescence in the wavelength band of 790 to 850 nm and reference light in the wavelength band of 790 to 810 nm are sequentially focused on the image pickup surface of the CCD14as return light from the site to be observed201.

When a determination result that the current time is not within the diagnosis available time of the second fluorescent drug (does not reach the diagnosis start time Ts2or exceeds the diagnosis end time Te2) is obtained by the determination circuit33d, even if switching operation from another observation mode to the second observation mode is performed in the mode changeover switch15, the switching control circuit33eof the control section33invalidates the switching operation by maintaining a control state for the motor9and the image pickup actuator control circuit32in a state before the switching operation is performed.

At a point when the determination result that the current time is within the diagnosis available time of the second fluorescent drug is obtained by the determination circuit33d, i.e., a point when the current time reaches the diagnosis start time Ts2of the second fluorescent drug, the switching control circuit33eof the control section33may apply control for shifting the observation mode to the second observation mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15.

On the other hand, when the determination result that the current time is not within the diagnosis available time of the second fluorescent drug is obtained by the determination circuit33d, the notification signal generating circuit61generates a character signal for displaying a character string for informing a period of time when switching to the second observation mode is impossible including a message that, for example, the current time does not reach the diagnosis start time Ts2of the second fluorescent drug or the current time exceeds the diagnosis end time Te2of the second fluorescent drug and outputs the character signal to the monitor4. When the determination result that the current time is not within the diagnosis available time of the second fluorescent drug is obtained by the determination circuit33d, the notification signal generating circuit61generates a sound signal for generating sound for informing the period of time when switching to the second observation mode is impossible including the message that, for example, the current time does not reach the diagnosis start time Ts2of the second fluorescent drug or the current time exceeds the diagnosis end time Te2of the second fluorescent drug and outputs the sound signal to the speaker63.

When a determination result that the current time exceeds the diagnosis end time Te2of the second fluorescent drug (Te2<T) is obtained by the determination circuit33d, the switching control circuit33eof the control section33applies control for switching the observation mode from the second observation to the below-described white color light observation mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15. In other words, the switching control circuit33eof the control section33stops the irradiation of the second illuminating light (the second excitation light) on the site to be observed201at timing when the current time exceeds the diagnosis end time Te2of the second fluorescent drug.

When switching operation to the white color light observation mode for irradiating white color light is performed in the mode changeover switch15(or when switching from another observation mode to the white color light observation mode is performed irrespective of an operation state of the mode changeover switch15), the switching control circuit33eof the control section33interposes the normal light filter50on the optical path of the lamp7by controlling the motor9of the light source apparatus1. In other words, in the white color light observation mode, frame-sequential illuminating light (white color light) including red light (R light) in the wavelength band of 600 to 650 nm, green light (G light) in the wavelength band of 500 to 600 nm, and blue light (B light) in the wavelength band of 400 to 500 nm is supplied to the light guide13.

Further, the switching operation to the white color light observation mode is performed in the mode changeover switch15(or when the switching from another observation mode to the white color light observation mode is performed irrespective of an operation state of the mode changeover switch15), the switching control circuit33eof the control section33controls the image pickup actuator control circuit32. By controlling the image pickup actuator control circuit32, the switching control circuit33eof the control section33causes the image pickup actuator39to set the arrangement state of the optical filter117aof the filter switching device39aand the arrangement state of the optical filter117bof the filter switching device39bin the second arrangement state (the retracted state).

Therefore, in the white color light observation mode, reflected lights of illuminating lights (R light, G light, and B light) emitted from the light guide13are sequentially focused on the image pickup surface of the CCD14as return light from the site to be observed201.

On the other hand, after applying the control for switching the observation mode to the white color light observation mode to the motor9and the image pickup actuator control circuit32, when a determination result that 0≦T≦Te2is further obtained by the determination circuit33d, the switching control circuit33eof the control section33controls the light adjustment circuit27to increase an aperture of the diaphragm12to thereby cause the light amount of the R light, the G light, and the B light to be respectively reduced to predetermined light amounts.

Specifically, the light adjustment circuit27increases the aperture of the diaphragm12such that the light amounts of the R light, the G light, and the B light emitted from the light source apparatus1are respectively equal to or smaller than predetermined values. In such a case, the light adjustment circuit27increases an amplification ratio of the amplification ratio control circuit29such that brightness of reflected lights of the R light, the G light, and the B light focused on the image pickup surface of the CCD14are suitable for observation.

Alternatively, the light adjustment circuit27reduces a light amount of the R light emitted from the light source apparatus1to be equal to or smaller than the predetermined value by relatively increasing, based on a timing signal from the timing generator30, the aperture of the diaphragm12at timing when the R light, a wavelength band of which overlaps the first or second excitation light, among the R light, the G light, and the B light is generated. In such a case, the color balance correction circuit20sets a color balance correction coefficient for making a color balance of an observation image corresponding to the reflected lights of the R light, the G light, and the B light suitable for observation (e.g., R:G:B=1:1:1) and performs adjustment of the color balance. The adjustment of the color balance involved in the reduction of the light amount of (the reflected light) of the R light is not limited to adjustment performed in the color balance correction circuit20alone and may be adjustment performed by the color balance correction circuit20and the color tone adjusting circuit24in association with each other.

The aperture of the diaphragm12(the light amounts of the R light, the G light, and the B light) controlled by the operation of the light adjustment circuit27in the white color light observation mode is a parameter set according to a discoloration characteristic of a fluorescent drug. One aperture may be able to be selected and set for each of types of fluorescent drugs out of plural diaphragm quantities by, for example, operation of the keyboard62. Alternatively the aperture may be stored in the storing circuit33bin a state in which the aperture is set in advance for each of the types of the fluorescent drugs.

On the other hand, for example, after applying the control for switching the observation mode to the white color light observation mode to the motor9and the image pickup actuator control circuit32, when the determination result that 0≦T≦Te2is further obtained by the determination circuit33d, the switching control circuit33eof the control section33may apply control for switching the normal light filter50provided in the filter wheel8to a not-shown filter for discoloration prevention.

As the filter for discoloration prevention, a filter configured to be capable of attenuating intensity of light in a wavelength band, which overlaps the first or second excitation light, among the R light, the G light, and the B light to predetermined intensity, for example, including characteristics shown inFIGS. 26 and 27can be applied.

FIG. 26is a diagram showing an example of the filter for discoloration prevention applicable in the present embodiment.FIG. 27is a diagram showing an example, which is different from the example shown inFIG. 26, of the filter for discoloration prevention applicable in the present embodiment.

The filter for discoloration prevention formed to include the characteristics illustrated inFIG. 26allows lights (the B light and the G light) in a wavelength band equal to or larger than 400 nm and smaller than 600 nm to pass without generally attenuating the lights. The filter for discoloration prevention attenuates light (the R light) in a wavelength band equal to or larger than 600 nm and equal to or smaller than 650 nm to about half intensity and allows the light to pass. Therefore, when the normal light filter50is switched to the filter for discoloration prevention including the characteristics illustrated inFIG. 26, the above-mentioned color balance adjustment is performed in the color balance correction circuit20(and the color tone adjusting circuit24).

The filter for discoloration prevention formed to include the characteristics illustrated inFIG. 27allows the lights (the B light and the G light) in the wavelength band equal to or larger than 400 nm and smaller than 600 nm to pass without generally attenuating the lights. The filter for discoloration prevention cuts off the light (the R light) in the wavelength band equal to or larger than 600 nm and equal to or smaller than 650 nm (attenuates intensity of the light to 0). Therefore, when the normal light filter50is switched to the filter for discoloration prevention including the characteristics illustrated inFIG. 27, processing for generating an observed image without using the reflected light of the R light is performed by the respective sections of the processor3.

The switching control circuit33eof the control section33may be configured to perform both the control for increasing the aperture of the diaphragm12and reducing the light amount of the R light and the control for switching the normal light filter50to the filter for discoloration prevention illustrated inFIG. 26and attenuating the intensity of the R light.

The configuration and the action of the present embodiment explained above are not limited to the case in which the first fluorescent drug and the second fluorescent drug are excited by the excitation lights in the wavelength bands different from each other to emit fluorescences. The configuration and the action of the present embodiment can be applied to, for example, a case in which the first fluorescent drug and the second fluorescent drug are excited by excitation lights in a same wavelength band to emit fluorescences.

On the other hand, according to the present embodiment, the endoscope system301may be configured using a dispensing unit71A shown inFIG. 28instead of using the dispensing unit71illustrated inFIG. 17.

FIG. 28is a diagram showing an example, which is different from the example shown inFIG. 17, of the configuration of the dispensing unit.

The dispensing unit71A includes, as shown inFIG. 28, chemical tanks71aand71din which chemicals including fluorescent drugs of kinds different from each other are stored in advance, a tubular member71bconnected to an opening of the chemical tank71a, a tubular member71econnected to an opening of the chemical tank71d, and a valve section71fprovided between the tubular members71band71eand the liquid feeding tube72.

The valve section71fincludes a valve member such as an electromagnetic valve between the tubular member71band the liquid feeding tube72. The valve section71fperforms an opening and closing operation for the valve member according to a valve switching signal outputted from the processor3to thereby start or stop supply of a chemical from the tubular member71bto the liquid feeding tube72. The valve section71fincludes a valve member such as an electromagnetic valve between the tubular member71eand the liquid feeding tube72. The valve section71fperforms an opening and closing operation for the valve member according to a valve switching signal outputted from the processor3to thereby start or stop supply of a chemical from the tubular member71eto the liquid feeding tube72.

Subsequently, action of the endoscope system301including the dispensing unit71A instead of the dispensing unit71is explained while the contents explained above are omitted as appropriate. In an example explained below, in the configuration in which the dispensing unit71A is used instead of the dispensing unit71, a chemical including the first fluorescent drug is stored in advance in the chemical tank71a, a chemical including the second fluorescent drug is stored in advance in the chemical tank71d, and the first fluorescent drug and the second fluorescent drug are administered to the same site to be observed201.

First, the surgeon or the like connects the respective sections of the endoscope system301and turns on the power supply to thereby start operations of the respective sections.

According to turn-on of the power supply for the processor3, output of a timing signal from the timing generator30is started.

The CCD driver31drives the CCD14based on a timing signal from the timing generator30according to, for example, the timing chart ofFIG. 18.

According to turn-on of a power supply for the light source apparatus1and start of an output of the timing signal from the timing generator30, rotation driving of the motor11is started. The interposing actions and the retracting actions for the optical filters41,42, and43are performed according to, for example, timing corresponding to the timing chart ofFIG. 19.

On the other hand, after connecting the respective sections of the endoscope system301and turning on the power supply, the surgeon or the like operates the keyboard62to thereby (cause the monitor4to display, for example, a setting screen related to various kinds of setting for the processor3) and sets the reference value Ns of an accumulation amount at diagnosis start time and the reference value Ne of an accumulation amount at diagnosis end time in observation performed using a fluorescent drug.

When the control section33detects that new reference values Ns and Ne are set by operation of the keyboard62, the control section33updates the reference values Ns and Ne stored in the storing circuit33b.

After performing the setting of the reference values Ns and Ne, the surgeon or the like operates the keyboard62to thereby input various kinds of information such as a type of the first fluorescent drug, an organ to which a target region (the site to be observed201) administered with the first fluorescent drug belongs, and a method of administering the first fluorescent drug to the target region.

After performing the setting of the reference values Ns and Ne, the surgeon or the like operates the keyboard62to thereby input various kinds of information such as a type of the second fluorescent drug, an organ to which a target region (the site to be observed201) administered with the second fluorescent drug belongs, and a method of administering the second fluorescent drug to the target region.

Further, the surgeon or the like operates the keyboard62to thereby input a diagnosis start scheduled time Tss serving as a scheduled time for starting diagnosis of the site to be observed201by both the first fluorescent drug and the second fluorescent drug.

On the other hand, after selecting table data coinciding with a type of the first fluorescent drug out of the table data of the plural fluorescent drugs stored in the storing circuit33b, the arithmetic processing circuit33aof the control section33further selects, out of the selected table data, one drug movement corresponding to a combination of an organ to which a target region (a site to be observed) administered with the first fluorescent drug belongs and a method of administering the first fluorescent drug to the target region. After selecting table data coinciding with a type of the second fluorescent drug out of the table data of the plural fluorescent drugs stored in the storing circuit33b, the arithmetic processing circuit33aof the control section33further selects, out of the selected table data, one drug movement corresponding to a combination of an organ to which a target region (a site to be observed) administered with the second fluorescent drug belongs and a method of administering the second fluorescent drug to the target region.

The arithmetic processing circuit33aof the control section33causes, based on the reference value Ns stored in the storing circuit33band the diagnosis start scheduled time Tss, a first elapsed time T when the accumulation amount N is Ns in the one drug movement selected out of the table data coinciding with the type of the first fluorescent drug and a first elapsed time T when the accumulation amount N is Ns in the one drug movement selected out of the table data coinciding with the type of the second fluorescent drug to coincide with the diagnosis start scheduled time Tss.

The arithmetic processing circuit33aof the control section33acquires an administration start time Ta1equivalent to time when the accumulation amount N of the first fluorescent drug is 0 and an administration start time Tas equivalent to time when accumulation amount N of the second fluorescent drug is 0 in a state in which the diagnosis start scheduled times Tss in the two drug movements, i.e., the drug movement of the first fluorescent drug and the drug movement of the second fluorescent drug are caused to coincide with each other.

The arithmetic processing circuit33aof the control section33acquires a diagnosis end time Te1equivalent to a last elapsed time T when the accumulation amount N of the first fluorescent drug is Ne in a state in which the diagnosis start scheduled times Tss in the two drug movements, i.e., the drug movement of the first fluorescent drug and the drug movement of the second fluorescent drug are caused to coincide with each other. Further, the arithmetic processing circuit33aof the control section33acquires a diagnosis end time Te2equivalent to a last elapsed time T when the accumulation amount N of the first fluorescent drug is Ne in a state in which the diagnosis start scheduled times Tss in the two drug movements, i.e., the drug movement of the first fluorescent drug and the drug movement of the second fluorescent drug are caused to coincide with each other.

FIG. 29is a diagram showing an example of a case in which the diagnosis start scheduled times in the drug movements shown inFIGS. 21 and 22are caused to coincide with each other.

Specifically, when the drug movement shown inFIG. 21is selected as the drug movement of the first fluorescent drug, the drug movement shown inFIG. 22is selected as the drug movement of the second fluorescent drug, and the reference value Ns is set equal to Ne, as illustrated inFIG. 29, the diagnosis start scheduled times Tss in these two drug movements are caused to coincide with each other, the administration start time Ta1and the diagnosis end time Te1of the first fluorescent drug are acquired, and the administration start time Ta2and the diagnosis end time Te2of the second fluorescent drug are acquired.

On the other hand, the determination circuit33dof the control section33performs, based on the administration start times Ta1and Ta2and a measurement result of the timing circuit33c, determination concerning whether the current time reaches the administration start time Ta1and determination concerning whether the current time reaches the administration start time Ta2. The determination circuit33dof the control section33performs, based on the diagnosis start scheduled time Tss, the diagnosis end time Te1, the diagnosis end time Te2, and a measurement result of the timing circuit33c, determination concerning whether the current time reaches the diagnosis start scheduled time Tss, determination concerning whether the current time reaches the diagnosis end time Te1, and determination concerning whether the current time reaches the diagnosis end time Te2.

An operation and the like performed in switching of the observation mode in the endoscope system301including the dispensing unit71A instead of the dispensing unit71are explained below. In the explanation, as an example, the diagnosis start scheduled time Tss, the administration start time Ta1, the diagnosis end time Te1, the administration start time Ta2, and the diagnosis end time Te2illustrated inFIG. 29are acquired.

The switching control circuit33eof the control section33controls the valve control circuit64based on a determination result of the determination circuit33dat timing when the current time reaches the administration start time Ta2of the second fluorescent drug to thereby start administration of the chemical including the second fluorescent drug to the site to be observed201. According to such control by the switching control circuit33e, the valve control circuit64sets the valve member between the tubular member71eand the liquid feeding tube72provided in the valve section71fof the dispensing unit71A in an open state for a fixed period, whereby the chemical including the second fluorescent drug is administered to the site to be observed201by an amount necessary for fluorescence observation.

The switching control circuit33eof the control section33controls the valve control circuit64based on a determination result of the determination circuit33dat timing when the current time reaches the administration start time Ta1of the first fluorescent drug to thereby start administration of the chemical including the first fluorescent drug to the site to be observed201. According to such control by the switching control circuit33e, the valve control circuit64sets the valve member between the tubular member71band the liquid feeding tube72provided in the valve section71fof the dispensing unit71A in an open state for a fixed period, whereby the chemical including the first fluorescent drug is administered to the site to be observed201by an amount necessary for fluorescence observation.

On the other hand, when a determination result that the current time does not reach the diagnosis start scheduled time Tss (T<Tss) is obtained by the determination circuit33d, the switching control circuit33eof the control section33applies control for switching the observation mode to the white color light mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15.

When a determination result that the current time is within a diagnosis available time by both the first fluorescent drug and the second fluorescent drug (Tss≦T≦Te2) is obtained by the determination circuit33d, the switching control circuit33eof the control section33interposes the third excitation light filter56on the optical path of the lamp7by controlling the motor9of the light source apparatus1when switching operation to a third observation mode for irradiating excitation light corresponding to the first and second fluorescent drugs is performed in the mode changeover switch15(or when switching from another observation mode to the third observation mode is performed irrespective of an operation state of the mode changeover switch15). In other words, in the third observation mode, frame-sequential third illuminating light including the reference light in the wavelength band of 790 to 810 nm, the first excitation light in the wavelength band of 600 to 650 nm, and the second excitation light in the wavelength band of 700 to 760 nm is supplied to the light guide13.

Further, when the determination result that the current time is within the diagnosis available time of both the first and second fluorescent drugs is obtained by the determination circuit33d, the switching control circuit33eof the control section33controls the image pickup actuator control circuit32when switching operation to the third observation mode is performed in the mode changeover switch15(or when switching from another observation mode to the third observation mode is performed irrespective of an operation state of the mode changeover switch15). By controlling the image pickup actuator control circuit32, the switching control circuit33eof the control section33causes the image pickup actuator39to operate to synchronize timing when the optical filters41,42, and43are sequentially interposed on the optical path of the lamp7, switching timing of an arrangement state of the optical filter117ain the filter switching device39a, and switching timing of an arrangement state of the optical filter117bin the filter switching device39b.

FIG. 30is a timing chart showing interposing actions and retracting actions in the third observation mode for the respective optical filters provided in the image pickup actuator.

Specifically, as shown inFIGS. 18,19, and30, in the third observation mode, in the exposure period of the CCD14and the period in which the optical filter41is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the first arrangement state (the interposed state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the second arrangement state (the retracted state). Further, as shown inFIGS. 18,19, and30, in the exposure period of the CCD14and the period in which the optical filter43is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the second arrangement state (the retracted state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the first arrangement state (the interposed state). On the other hand, as shown inFIGS. 18,19, and30, in the third observation mode, in the readout period of the CCD14or the period in which the optical filter42is interposed on the optical path of the lamp7, the image pickup actuator control circuit32sets the arrangement state of the optical filter117aof the filter switching device39ain the second arrangement state (the retracted state) and sets the arrangement state of the optical filter117bof the filter switching device39bin the second arrangement state (the retracted state).

Therefore, in the third observation mode, the first fluorescent drug and the second fluorescent drug are excited by the third illuminating light (the first excitation light and the second excitation light) emitted from the light guide13. Therefore, the first fluorescence in the wavelength band of 680 to 750 nm, the second fluorescence in the wavelength band of 790 to 850 nm, and the reference light in the wavelength band of 790 to 810 nm are sequentially focused on the image pickup surface of the CCD14as return light from the site to be observed201.

When a determination result that the current time is not within the diagnosis available time of both the first and second fluorescent drugs is obtained by the determination circuit33d, even if switching operation from another observation mode to the third observation mode is performed in the mode changeover switch15, the switching control circuit33eof the control section33invalidates the switching operation by maintaining a control state for the motor9and the image pickup actuator control circuit32in a state before the switching operation is performed.

On the other hand, when the determination result that the current time is not within the diagnosis available time of both the first and second fluorescent drugs is obtained by the determination circuit33d, the notification signal generating circuit61generates a character signal for displaying a character string for informing a period of time when switching to the third observation mode is impossible including a message that, for example, the current time does not reach the diagnosis start scheduled time Tss or the current time exceeds the diagnosis end time Te2of the second fluorescent drug and outputs the character signal to the monitor4. When the determination result that the current time is not within the diagnosis available time of both the first and second fluorescent drugs is obtained by the determination circuit33d, the notification signal generating circuit61generates a sound signal for generating sound for informing the period of time when switching to the third observation mode is impossible including the message that, for example, the current time does not reach the diagnosis start scheduled time Tss or the current time exceeds the diagnosis end time Te2of the second fluorescent drug and outputs the sound signal to the speaker63.

The notification signal generating circuit61may operate to perform the respective notifications at a point when the current time reaches the diagnosis start scheduled time Tss and the diagnosis end time Te2or operate to cause the monitor4to always display the diagnosis start scheduled time Tss and the diagnosis end time Te2based on a determination result of the determination circuit33d.

When a determination result that the current time exceeds the diagnosis end time Te2and is within the diagnosis available time of the first fluorescent drug (Te2≦T≦Te1) is obtained by the determination circuit33d, the switching control circuit33eof the control section33invalidates the switching operation to the third observation mode and applies control for switching the observation mode to the first observation mode to the motor9and the image pickup actuator control circuit32.

When a determination result that the current time exceeds the diagnosis end time Te1(Te1<T) is obtained by the determination circuit33d, the switching control circuit33eof the control section33applies control for switching the observation mode from the first observation to the white color light observation mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15.

When the determination result that the current time exceeds the diagnosis end time Te2and is within the diagnosis available time of the first fluorescent drug is obtained by the determination circuit33d, the notification signal generating circuit61generates a character signal for displaying a character string including a message that, for example, the observation mode is switched to the first observation mode because of a period of time when switching to the third observation mode is impossible and outputs the character signal to the monitor4. When the determination result that the current time exceeds the diagnosis end time Te2and is within the diagnosis available time of the first fluorescent drug is obtained by the determination circuit33d, the notification signal generating circuit61generates a sound signal for generating sound including a message that, for example, the observation mode is switched to the first observation mode because of a period of time when switching to the third observation mode is impossible and outputs the sound signal to the speaker63.

The switching control circuit33eof the control section33may apply, based on a determination result obtained by the determination circuit33d, control for shifting the observation mode from the white color light observation mode to the third observation mode to the motor9and the image pickup actuator control circuit32irrespective of an operation state of the mode changeover switch15at a point when the current time reaches the diagnosis start scheduled time Tss. Further, when the current time reaches the diagnosis start scheduled time Tss and enters a period of time within the diagnosis available time of both the first and second fluorescent drug, the switching control circuit33eof the control section33may apply control for shifting the observation mode from the white color light observation mode to the third observation mode to the motor9and the image pickup actuator control circuit32when switching operation to the third observation mode is performed in the mode changeover switch15.

The notification signal generating circuit61may operate to cause the monitor4to display a message for urging administration of the first fluorescent drug and (or) cause the speaker63to output sound at a point when the current time reaches the diagnosis start time Ta1based on a determination result of the determination circuit33d. The notification signal generating circuit61may operate to cause the monitor4to display a message for urging administration of the second fluorescent drug and (or) cause the speaker63to output sound at a point when the current time reaches the diagnosis start time Ta2based on a determination result of the determination circuit33d. The notification signal generating circuit61performs such an operation, whereby, as an administering method for the first fluorescent drug and the second fluorescent drug, it is also possible to adopt an administering method other than a method of administering the first and second fluorescent drugs using the dispensing unit71A such as oral administration or intravenous injection administration.

As explained above, according to the present embodiment, when fluorescence emitted from a fluorescent drug administered to a site to be observed of a subject, it is possible to suppress generation of fluorescence in times other than a period of time when diagnosis of the site to be observed is possible. As a result, it is possible to realize improvement of a diagnosis ability in performing diagnosis of the site to be observed.

The present invention is not limited to the embodiment explained above. It goes without saying that various modifications and applications are possible without departing from the spirit of the invention.