JP2007303990A - Fluorescence diagnostic equipment - Google Patents

Abstract

Provided is a fluorescence diagnostic apparatus capable of significantly suppressing loss of fluorescence information.
An excitation light source 1 oscillates excitation light having a peak wavelength shorter than the central wavelength of fluorescence of the photosensitive substance and having a difference from the central wavelength of fluorescence of the photosensitive substance of more than 12 nm and not more than 16 nm. . The excitation light is irradiated to the lesion part 5 through the collimating lens 2 and the excitation light wavelength shaping means 3. The fluorescence 6 of the photosensitive material excited by the excitation light is separated from the reflected light 7 of the excitation light by the light separating means 8 and enters the imaging device 9. The light separating means 8 has the center wavelength of the band cut filter that coincides with or near the peak value of the excitation light.
[Selection] Figure 1

Description

  The present invention relates to a fluorescence diagnostic apparatus used for a photodynamic diagnostic method.

  In recent years, PDT (photodynamic therapy) and PDD (photodynamic diagnostic methods) using a combination of a tumor-affinity / photosensitive substance (hereinafter referred to as a drug) and laser light have been used in the treatment and diagnosis of lesions centered on tumors. It has come to be utilized. PDT is a treatment method in which a drug accumulated in a lesion is irradiated with a laser beam, and the lesion is killed by utilizing the oxidizing action of active oxygen obtained by the excitation of the drug. By observing the fluorescence emitted when a part of the excited drug returns to the ground state, the site of the lesion is recognized. The present invention relates to this PDD. Specific examples of PDD utilization are shown below.

  For example, currently performed brain tumor surgery involves a surgical plan based on navigation of MRI images and the like, and the operation proceeds. However, once the tumor is removed, the tumor cannot be distinguished from normal tissue macroscopically. In addition, since the position of the brain tissue changes under the influence of the pressure change due to the primary removal of the tumor, the actual state during the operation and the MRI image taken before the operation do not match. As described above, in the current technique, it is difficult to confirm the tumor remaining after the primary excision, and a large technical problem remains in 100% excision of the tumor.

  When PDD is used for such a problem, fluorescence is observed from the tumor remaining after the primary excision. Secondary extraction may be performed with this fluorescent guide, and it can be expected that the tumor extraction rate will be significantly improved.

  As this PDD, there are a method of exciting with blue light in the vicinity of 405 nm corresponding to the maximum absorption wavelength band of the drug and a method of using red light in the 600 nm range corresponding to the maximum absorption wavelength band used for treatment. An example of fluorescence diagnosis using excitation light in this maximum absorption wavelength band is described in Patent Document 1. In Patent Document 1, for example, in fluorescence diagnosis using a drug having a maximum absorption wavelength of 664 nm and a fluorescence center wavelength of 672 nm, the difference between the excitation light and the fluorescence wavelength peak is set to 12 nm or less, and the excitation light reflected by the living body is detected. It is described that fluorescence information is obtained by removing or cutting by a light separation means.

JP-A-7-270718

  However, when the wavelength peak difference between the excitation light and the fluorescence is set to be relatively small as described above, fluorescence observation is possible. However, the excitation light and the fluorescence having a wide wavelength width overlap each other. Even if only the fluorescence information is obtained by cutting, there is a technical problem that most of the fluorescence information is removed by the light separation means.

  In view of the above-described conventional problems, an object of the present invention is to provide a fluorescence diagnostic apparatus that can significantly suppress loss of fluorescence information.

  The present invention is a fluorescence diagnostic apparatus for observing the lesion based on the fluorescence of the photosensitive substance accumulated in the lesion, wherein the peak value of the wavelength is shorter than the central wavelength of the fluorescence of the photosensitive substance And an excitation light source that oscillates excitation light in which the difference between the peak value and the central wavelength of fluorescence of the photosensitive substance is greater than 12 nm and less than or equal to 16 nm, a collimator lens that collimates the excitation light, and the collimator lens The excitation light entering the lesion site is incident, and coincides with the peak value of the excitation light, or an excitation light wavelength shaping means having a center wavelength of a bandpass filter in the vicinity thereof, and the light sensitivity excited by the excitation light. The fluorescence of the substance and the reflected light of the excitation light at the lesion are incident and coincide with or near the peak value of the excitation light. Comprising a light separating means, and an imaging device for imaging the fluorescence information obtained by said light separating means having to provide a fluorescence diagnosis device.

  The peak value of the wavelength of the excitation light and the center wavelength of the band cut filter of the light separating means are set so as to be shifted to the short wavelength side by an amount that is greater than 12 nm and less than or equal to 16 nm with respect to the fluorescence center wavelength of the photosensitive material. With this configuration, without using an expensive band cut filter with a narrow band cut width as a light separation means, loss of fluorescence information can be suppressed as much as possible to obtain more fluorescence information, and highly accurate fluorescence diagnosis can be performed. realizable.

  The photosensitive substance is, for example, talaporfin sodium. This talaporfin sodium has a fluorescence center wavelength of 672 nm, a maximum absorption wavelength of 664 nm, and a maximum absorption wavelength of 411 nm.

  The band cut width of the light separating means may be about 10 ± 2 nm (for example, 9 nm), and it is not necessary to use an expensive filter having a narrow band cut width (for example, about 4 nm).

  The fluorescence diagnostic apparatus according to the present invention includes an auxiliary excitation light source configured to have a wavelength component in a range of 408 nm to 430 nm and generating auxiliary excitation light irradiated to the lesion, and the auxiliary excitation reflected from the lesion You may further provide the removal means which removes light. By providing such an auxiliary excitation light source and irradiating the lesion site with auxiliary excitation light in the maximum absorption wavelength band, the intensity of fluorescence emitted by the photosensitive substance can be increased, and the accuracy of fluorescence diagnosis can be further improved.

  Alternatively, the fluorescence diagnostic apparatus of the present invention includes auxiliary components for generating auxiliary excitation light that includes wavelength components in the range of 408 nm to 430 nm and includes a plurality of wavelength components that exceed 430 nm and that is irradiated to the lesion. It may further comprise a light source and a removing means for removing a component of 430 nm or less of the auxiliary excitation light reflected from the lesion. Specifically, the auxiliary excitation light source is a combination of a blue diode containing a wavelength component in the range of 408 nm or more and 430 nm or less and a diode in a wavelength region such as red or green, or a white light emission by combining a blue diode and a fluorescent material. Made up of. By providing such an auxiliary excitation light source and irradiating the lesion area with auxiliary excitation light in the maximum absorption wavelength band of the photosensitive substance, the photosensitive substance emits strong fluorescence, so the accuracy of diagnosis by the fluorescence information imaged by the imaging device Can be further improved. Further, an image (for example, a white image) other than the fluorescent image can be obtained by a combination of the output of the auxiliary excitation light source and the setting of the characteristics of the removing means.

  According to the fluorescence diagnostic apparatus of the present invention, a photosensitive substance is administered to a living body and accumulated in a lesion, and the peak value of the wavelength with respect to the lesion is shorter than the central wavelength of fluorescence of the photosensitive substance, and the light Irradiation with excitation light whose difference from the central wavelength of fluorescence of the sensitive substance is more than 12 nm and not more than 16 nm, and fluorescence of the photosensitive substance excited by the excitation light and reflected light of the excitation light at the lesion Is incident on a light separating means that coincides with or near the peak value of the excitation light and has a center wavelength of a band cut filter, and separates the fluorescence from the reflected light, and obtains a fluorescence obtained from the light separating means. A fluorescence diagnostic method for imaging information can be performed.

  In the fluorescence diagnostic apparatus of the present invention, the peak wavelength of the excitation light and the center wavelength of the band-cut filter of the light separating means are shorter than the center wavelength of the light-cutting means by 12 nm or less with respect to the fluorescence center wavelength of the photosensitive substance. By shifting to the side, loss of fluorescence information can be suppressed and more fluorescence information can be obtained without using an expensive band-cut filter with narrow band-cut width as a light separation means, and high-accuracy fluorescence diagnosis Can be realized. Therefore, the fluorescence diagnostic apparatus of the present invention can provide an efficient PDD at a surgical site such as a brain tumor, and can contribute to improvement of therapeutic results by preventing the tumor from being left behind.

(Embodiment 1)
In FIG. 1, 1 is an excitation light source that oscillates excitation light, 2 is a collimating lens provided to accurately shape the wavelength of the oscillated excitation light, and 3 is the wavelength of the excitation light collimated by the collimating lens 2. Excitation light wavelength shaping means for cutting the spreading tail, 4 is shaped excitation light whose wavelength tail is cut by the excitation light wavelength shaping means, and 5 is a lesion part of a living body such as a tumor to be fluorescence observed, which will be described later. The drug to be administered has been administered in advance. 6 is fluorescence obtained as a result of excitation of the medicine accumulated in the lesion part 5 by 4 shaping excitation light 4, 7 is reflection shaping excitation light that is the shaping excitation light 4 reflected by the lesion part 5, and 8 is the lesion part. A light separating means for transmitting the fluorescence 6 from the light information obtained from the light 5 and reflecting the reflection shaping excitation light 7. Reference numeral 9 denotes an imaging device that reads the fluorescence 6 selected as necessary information by the light separation means 8, and the captured image is displayed on the image display device 11. Reference numeral 10 denotes a lens, which is used when the distance between the light separating means 8 and the lesion portion 5 cannot be secured and the cut characteristics of the light separating means 8 cannot be sufficiently exhibited.

  The PDD using the fluorescence diagnostic apparatus constructed as described above is talaporfin sodium which is a chlorin-based drug having a maximum absorption wavelength of 664 nm and a fluorescence center wavelength of 672 nm as a drug (trademark registered Rezaphyrin manufactured by Meiji Seika Co., Ltd.) ) Will be described as an example.

  After a certain amount of time after drug administration, the excitation light source 1 oscillates excitation light in a state where the degree of drug accumulation in the lesion 5 is increased. The peak value of the wavelength of the excitation light oscillated by the excitation light source 1 is shorter than the center wavelength (672 nm) of the fluorescence of the drug, and the difference between the peak value of the wavelength of the excitation light and the center wavelength of the drug is more than 12 nm and less than 16 nm. is there. In other words, the peak value of the wavelength of the excitation light is set so as to be shifted to the short wavelength side by an amount greater than 12 nm and not greater than 16 nm with respect to the central wavelength of the fluorescence of the drug. In such a range, the peak value of the wavelength of the excitation light is 656 nm or more and less than 660 nm, but in the following description, the peak value of the wavelength of the excitation light is 656 nm as a representative.

  The excitation light oscillated by the excitation light source 1 is collimated by the collimating lens 2 as preprocessing for wavelength shaping. In the collimated excitation light, the bottom component of the wavelength of the excitation light that becomes an obstacle in fluorescence observation is cut by the excitation light shaping means 3 having bandpass characteristics matching the oscillated excitation light wavelength. By this wavelength shaping, shaped excitation light 4 having a narrow wavelength width from which the wavelength base is cut is obtained. The reason for cutting the base of the wavelength of the excitation light will be described in detail later.

  By irradiating the lesioned part 5 with the shaped excitation light 4, the drug accumulated in the lesioned part 5 is excited. A part of the excited drug immediately returns to the ground state, but weak fluorescence 6 having a central wavelength at 672 nm is emitted by the energy obtained at this time. At the same time, the irradiated shaped excitation light 4 becomes reflected shaped excitation light 7 from the lesion 5. The fluorescence 6 and the reflection shaping excitation light 7 enter the light separating means 8. Since the fluorescence 6 is significantly weaker than the reflection shaping excitation light 7, the fluorescence 6 is buried in the reflection shaping excitation light 7. The light separating means 8 is provided in order to obtain fluorescence 6 from the reflection shaping excitation light 7, that is, only necessary fluorescence information. The light separating means 8 is composed of a band cut filter, and the center wavelength of the band cut filter is set so as to be shifted to the short wavelength side by an amount of more than 12 nm and not more than 16 nm with respect to the fluorescence center of the drug. In other words, the light separating means 8 matches the center wavelength of the excitation light (656 nm in this embodiment as described above). Further, the band cut filter constituting the light separating means 8 has a band cut band wider than the wavelength width of the shaped excitation light 4. As the light separating means 8, for example, a notch filter (band cut width 9 nm) manufactured by Kaiser Optical Systems can be used. Unnecessary reflection shaping excitation light 7 is reflected by this light separating means 8 and light information other than the necessary fluorescence 6 and band cut band (hereinafter referred to as white light information) is transmitted. The lesioned part 5 is photographed by the imaging device 9 using the transmitted fluorescence 6 and white light information as light information, and can be recorded and displayed on the image display device 11.

  As described above, in this fluorescence diagnostic apparatus, the peak value of the wavelength of the excitation light, the center wavelength of the band pass filter constituting the excitation light shaping means 3, and the center wavelength of the band cut filter of the light separating means 8 are determined. It is set so as to be shifted to the short wavelength side by an amount exceeding 12 nm and not more than 16 nm with respect to the center wavelength of the fluorescence 6. Specifically, this fluorescence diagnostic apparatus includes an excitation light source 1 that oscillates excitation having a center wavelength of 656 nm, excitation light shaping means 3 having a center wavelength at 656 nm, and light separation means 8 having a center wavelength at 656 nm. Yes. Such a configuration enables efficient collection of fluorescence information. Hereinafter, the reason will be described in detail with reference to FIG.

  2A and 2B show the relationship between the fluorescence spectrum band, the excitation light, and the band cut wavelength band of the light separating means 8. FIG. 2A is an example in which the difference between the peak value of the wavelength of the excitation light 4 ′ and the center wavelength (672 nm) of the fluorescence 6 ′ is set to be relatively small according to the conventional method. The peak value is 664 nm (equal to the maximum absorption wavelength of the drug and 8 nm shorter than the central wavelength of fluorescence). On the other hand, FIG. 2 (B) is an example in which the peak value of the wavelength of the excitation light 4 is set to be shifted to the short wavelength side by an amount that is greater than 12 nm and less than or equal to 16 nm with respect to the center wavelength of the fluorescence 6 according to the present invention. The peak value of the wavelength of 4 is 656 nm (16 nm shorter than the central wavelength of fluorescence). 2A and 2B, the center wavelength of the band cut of the light separating means 8 coincides with the peak value of the pumping light 4 and 4 ', and the band cut wavelength widths 21' and 21 are approximately equal to each other. It is set to 10 nm.

  As is clear from FIG. 2A, when the difference between the peak value of the wavelength of the excitation light 4 ′ and the center wavelength of the fluorescence 6 ′ is set to be relatively small according to the conventional method, most of the fluorescence 6 is obtained. The fluorescence 6 (region 6b ′) that is cut by the light separating means 8 (region 6a ′) and remains without being cut by the light separating means 8 is weak. In other words, in the case of FIG. 2A, the efficiency of extracting fluorescent information by the light separating means 8 is low. On the other hand, as apparent from FIG. 2 (B), when the peak value of the wavelength of the excitation light 4 is set sufficiently shifted to the short wavelength side with respect to the central wavelength of the fluorescence according to the present invention, the light separating means 8 As compared with FIG. 2A, the fluorescence (region 6a) cut by (1) is greatly reduced, and the fluorescence 6 (region 6b) remaining without being cut by the light separating means 8 is greatly enhanced. In other words, according to the present invention (FIG. 2A), the loss of fluorescence information due to being cut by the light separating means 8 is reduced, and the fluorescence information can be collected with high efficiency.

  Excitation efficiency (ratio of regions 6a ′ and 6a extracted as fluorescence information in the fluorescence 6 in FIGS. 2A and 2B) is 660 nm (the peak wavelength of the excitation light is 12 nm shorter than the center wavelength of the fluorescence 6), 664 nm. (FIG. 2 (A)) and the case of 656 nm (FIG. 2 (B)) were estimated. As a result, when the excitation efficiency of 664 nm excitation was 100, 660 nm excitation was 140 (40% improvement), and 656 nm excitation was 161 (61% improvement). Thus, the excitation efficiency is greatly improved by shifting the peak value of the wavelength of the excitation light 4 to the short wavelength side by an amount greater than 12 nm and less than or equal to 16 nm with respect to the center wavelength of the fluorescence 6. Specifically, by setting the peak value of the wavelength of the excitation light 4 within this range, an improvement in excitation efficiency exceeding 40% can be achieved as compared with the case of 664 nm excitation.

  It can be considered that the light separation means 8 and the band cut band are narrowed (for example, a super notch filter manufactured by Kaiser Optical Systems Co., Ltd .: band cut width 4 nm) to reduce the cut rate of the fluorescence 6, thereby improving the excitation efficiency. However, since a band cut filter with a narrow band cut band is significantly expensive, it lacks practicality. On the other hand, in the present embodiment, the peak value of the wavelength of the excitation light is relatively shifted to the short wavelength side with respect to the central wavelength of the fluorescence, so that the band cut band of the light separating means 8 is set to be excessively narrow. Even without this, high excitation efficiency as described above can be obtained. Specifically, the band cut width of the band cut filter constituting the light separating means 8 may be set to about 10 ± 2 nm.

  As described above, according to the fluorescence diagnostic apparatus of the present embodiment, loss of fluorescence information can be suppressed and more fluorescence information can be obtained without using an expensive band cut filter with a narrow band cut width as a light separating means. It is possible to obtain a highly accurate fluorescence diagnosis.

  The reason why the base of the excitation light is cut by the excitation light wavelength shaping means 4 will be described with reference to FIG. As can be seen from the pumping light-transmitted light characteristic of FIG. 3A, the base of the pumping light becomes wider when it becomes a value of 1/1000 or less from the power peak value. Therefore, even if the light separation means 8 having a band cut characteristic of about 11 nm or more is inserted and the reflected excitation light 7 is cut, if reflected excitation light that is wider than the cut width enters, the band cut region of the light separation means 8 The light protrudes and becomes transmitted light. This transmitted light is an obstacle to weak fluorescence observation. On the other hand, when the wavelength shaping filter is inserted as shown in FIG. 3 (B) and the excitation light is shaped and then the excitation light is transmitted through the light separating means 8, the light as shown in FIG. 3 (C). No light is transmitted through the separating means 8. On the other hand, when the light separating means 8 having a significantly wider cut width is used, there is no need for the tail cut of the excitation light and wavelength shaping becomes unnecessary, but at the same time, the fluorescence information is largely cut. In addition, the red component of the white light information is significantly cut, and the color balance of the image is lost, resulting in an ugly image.

  In addition, when excitation efficiency falls, it is possible to make up for lack of fluorescence intensity by raising excitation light intensity. In this case, since the efficiency as the treatment light is lowered by shifting the peak value of the excitation light to the short wavelength side, the treatment does not proceed by increasing the intensity of the excitation light. .

  FIG. 4 is a photograph of the brain tumor after the drug (talaporfin sodium) was accumulated and the tumor was first excised. FIG. 5 and FIG. 6 show fluorescence images (displayed on the image display device 11) captured by the imaging device 9 by irradiating the brain tumor with excitation light of 664 nm by the fluorescence diagnostic device of the present embodiment. FIG. 6 is an enlarged view of the upper right part of FIG. 5, and the fluorescence is remarkable in the part surrounded by the broken line, indicating that the tumor to be secondarily excised remains. As described above, the fluorescent device according to the present embodiment can provide an efficient PDD at the surgical site, and can contribute to improvement of treatment results by preventing the tumor from being left behind.

(Embodiment 2)
Referring to FIG. 7, a general drug has a maximum absorption wavelength band in the vicinity of 400 nm with respect to a maximum absorption wavelength on the order of 600 nm. Similarly, in the case of talaporfin sodium, there is a maximum absorption wavelength band at 411 nm in vivo. As shown in FIG. 7, it is clear that strong fluorescence is obtained because the absorbance at the maximum absorption wavelength is much higher than the absorbance at the maximum absorption wavelength (664 nm). FIG. 8 shows a configuration in which a second excitation light source that matches this maximum absorption wavelength is provided as auxiliary excitation light, and light in the vicinity of 411 nm is irradiated onto the lesion.

  The configuration of the fluorescence diagnostic apparatus in FIG. 8 is almost the same as that of the first embodiment, and only different points will be described below. Reference numeral 12 denotes an auxiliary excitation light source that emits light in the vicinity of 411 nm, which is the maximum absorption wavelength of the drug, specifically, 408 nm to 430 nm, 13 is auxiliary excitation light emitted from the auxiliary excitation light source, and 14 is reflected from the lesion portion 5. The reflection auxiliary excitation light 15 is a first high-pass filter that cuts the reflection auxiliary excitation light 14 and transmits a wavelength of 450 nm or more. Reference numeral 16 denotes a second high-pass filter that cuts a light component of less than 408 nm contained in the auxiliary excitation light source, and is disposed only when the light oscillated by the auxiliary excitation light source 12 contains a wavelength component of less than 408 nm.

  When the fluorescence diagnostic apparatus of FIG. 8 is used to simultaneously observe the fluorescence of the lesion portion 5 by simultaneously irradiating the 656 nm shaped excitation light 4 and the auxiliary excitation light 13 near 411 nm, the lesion portion 5 is as in the first embodiment. Fluorescence 6 is emitted stronger than when only 656 nm excitation light is irradiated. Similarly to the first embodiment, the reflection auxiliary excitation light 14 of the auxiliary excitation light 13 becomes obstructive light when observing the fluorescence of the lesion 5, but the reflection auxiliary excitation light 14 is cut by the first high-pass filter 15. Therefore, only the fluorescence image is captured by the imaging device 9. As described above, strong fluorescence is emitted by irradiating auxiliary excitation light in the vicinity of the maximum absorption wavelength (411 nm) in addition to excitation light (for example, 656 nm) in the wavelength region corresponding to the maximum absorption wavelength, and highly accurate fluorescence observation is achieved. It becomes possible.

(Embodiment 3)
The fluorescence diagnostic apparatus of the third embodiment has the same configuration as that of the second embodiment (FIG. 5) except for the auxiliary excitation light source 12. Similarly to Embodiments 1 and 2, a drug (talaporfin sodium) is accumulated in the lesion 5.

  In this embodiment, the auxiliary excitation light source 12 is an auxiliary light source composed of wavelength components of a wavelength range of 408 nm or more and a wavelength component of 430 nm or less, which is the long wavelength end of the maximum absorption wavelength band of the drug, including wavelength components. Oscillates excitation light. For example, the auxiliary excitation light source 12 is a light source that combines a blue LED that oscillates light having a wavelength component of 408 nm or more and 430 nm or less and an LED that emits light of another wavelength region such as red or green. The auxiliary excitation light source 12 may emit white light by combining a blue LED that oscillates light having a wavelength component of 408 nm or more and 430 nm or less and a fluorescent material.

  When the fluorescence diagnostic apparatus of this embodiment simultaneously irradiates the 656 nm shaped excitation light 4 and the auxiliary excitation light 13 and observes the fluorescence of the lesion part 5, the lesion part 5 has a wavelength of 656 nm as in the first embodiment. A stronger fluorescence 6 is emitted than when only excitation light is irradiated. Similarly to Example 1, there is reflection auxiliary excitation light 14 of auxiliary excitation light 13 and it becomes obstructive light for observation, but only a fluorescent image is captured by cutting components of 430 nm or less by 15 high-pass filters 1. Captured by the device. Furthermore, an image (for example, a white image) other than the fluorescent image can be obtained by combining the output of the auxiliary excitation light source 13 (the intensity of the auxiliary excitation light) and the transmission characteristics of the high-pass filter 15.

  FIG. 9A is an image obtained by observing a brain tumor with 664 nm excitation light alone. On the other hand, FIG. 9B is an image irradiated with excitation light of 664 nm and white LED light containing wavelength components of 408 nm to 430 nm as auxiliary excitation light. In FIG. 9A, although it is weak, a white light image is observed and the intensity of fluorescence is enhanced.

  The fluorescence diagnostic apparatus according to the present invention can provide an efficient PDD at a surgical site such as a brain tumor, and can contribute to improvement of therapeutic results by preventing the tumor from being left behind.

1 is a schematic diagram showing an overall configuration of a fluorescence diagnostic apparatus according to a first embodiment of the present invention. It is a schematic diagram which shows the optical relationship of excitation light and fluorescence, (A) shows the case where the wavelength of excitation light is 664 nm, (B) shows the case where the wavelength of excitation light is 656 nm. (A) is a diagram showing the relationship between the excitation light when not shaped and the transmitted light from the light separating means, (B) is a diagram showing the excitation light before and after shaping, and (C) is the excitation light before shaping. And a diagram showing the characteristics of the transmitted light from the light separating means by the shaped excitation light. Photograph of brain tumor after primary excision of tumor. A photograph of the brain tumor after primary excision of the tumor taken with excitation light. 6 is a partially enlarged photograph of FIG. The figure which shows the absorption spectrum of the chemical | medical agent used for Embodiment 1, 2, and 3 of the fluorescence diagnostic apparatus of this invention. FIG. 4 is a schematic diagram showing an overall configuration of a fluorescence diagnostic apparatus according to second and third embodiments of the present invention. (A) is a photograph of a brain tumor taken by irradiating only 664 nm excitation light, and (B) is a photograph of a brain tumor taken by irradiating 664 nm excitation light and a white LED.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Excitation light source 2 Collimating lens 3 Excitation light source wavelength shaping means 4, 4 'shaping excitation light 5 Foci 6 Fluorescence 7 Reflection shaping excitation light 8 Light separation means 9 Imaging device 10 Lens 11 Image display device 12 Auxiliary excitation light source 13 Auxiliary excitation light 13 14 Reflective auxiliary excitation light 15,16 High pass filter 21, 21 'Band cut region

Claims (5)

A fluorescence diagnostic apparatus for observing the lesion based on fluorescence of a photosensitive substance accumulated in the lesion,
An excitation light source that oscillates excitation light whose wavelength peak value is shorter than the central wavelength of fluorescence of the photosensitive substance and whose difference between the peak value and the central wavelength of fluorescence of the photosensitive substance is more than 12 nm and not more than 16 nm When,
A collimating lens for collimating the excitation light;
Excitation light wavelength shaping means having the central wavelength of a band pass filter in the vicinity of or coincident with the peak value of the excitation light is incident on the excitation light from the collimating lens toward the lesion.
The fluorescence of the photosensitive substance excited by the excitation light and the reflected light of the excitation light at the lesion are incident, and coincide with or near the peak value of the excitation light, and the central wavelength of the band cut filter A light separating means having
An imaging apparatus comprising: an imaging device that images fluorescence information obtained by the light separation means.   The fluorescence diagnostic apparatus according to claim 1, wherein the photosensitive substance is talaporfin sodium.   The fluorescence diagnostic apparatus according to claim 1 or 2, wherein a band cut width of the light separating means is 10 ± 2 nm. An auxiliary excitation light source configured to have a wavelength component in a range of 408 nm or more and 430 nm or less and generating auxiliary excitation light irradiated to the lesion;
The fluorescence diagnostic apparatus according to any one of claims 1 to 3, further comprising: a removing unit that removes the auxiliary excitation light reflected by the lesion. An auxiliary excitation light source configured to include a wavelength component in a range of 408 nm to 430 nm and including a plurality of wavelength components exceeding 430 nm, and generating auxiliary excitation light irradiated to the lesion;
The fluorescence diagnostic apparatus according to any one of claims 1 to 3, further comprising: a removing unit that removes a component of 430 nm or less of the auxiliary excitation light reflected by the lesion part.