WO2012143800A1

WO2012143800A1 - Method and device for fluorescence guided surgery to improve intraoperative visualization of biliary tree

Info

Publication number: WO2012143800A1
Application number: PCT/IB2012/051081
Authority: WO
Inventors: Yasser Fawzy; Amr Mohsen; Mahmod ELBASIOUNY
Original assignee: Yasser Fawzy; Amr Mohsen; Elbasiouny Mahmod
Priority date: 2011-04-19
Filing date: 2012-03-08
Publication date: 2012-10-26

Abstract

A method and device for improving intraoperative visualization of luminal structures by fluorescent internal illumination is disclosed. Primary focus is on bile duct visualization in order to allow performance of safe laparoscopic cholecystectomy. The method is based on injecting fluorescent dye either directly in the gallbladder or intravenously so that a fluorescence emission can be induced and a fluorescence image of the biliary system can be detected. The device can comprise a light source (typically high power light emitting diode) producing UV and/or Blue light through and a cylindrical sterilizable or disposable tubular probe with a diameter between 5-15mm. The tubular probe can have an embedded light guide such as a liquid light guide to transmit the light generated by the external UV source to an area under examination, and an inner hollow channel to allow for inserting a surgical instrument (such as dissection instrument). The device can be used during laparoscopic procedures as an integrated device to laparscopic imaging system or as stand-alone imaging system. The device can also be used in open surgery in different parts of the body where it can be introduced through a wound that is used to access the operative field.

Description

METHOD AND DEVICE FOR FLUORESCENCE GUIDED SURGERY TO IMPROVE INTRAOPERATIVE VISUALIZATION OF BILIARY TREE

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 61/476,758, filed April 19, 2011, entitled "METHOD AND DEVICE FOR FLUORESCENCE GUIDED SURGERY TO IMPROVE INTRAOPERATIVE VISUALIZATION OF BILIARY TREE AND OTHER ANATOMICAL STRUCTURES," which is hereby incorporated by reference herein in its entirety.

BACKGROUND

Technical Field

This invention relates to a method and a device for biliary tree visualization during laparoscopic cholecystectomy or open cholecystectomy and more particularly to a method and a device for real-time visible light fluorescence of the biliary tree.

Description of the Related Art Disease of the gallbladder often requires its surgical removal. The surgical removal of the gallbladder is called cholecystectomy. This is an invasive surgical method, often followed with complication due to infections and with longer time for patient recovery. In order to handle some of the drawbacks of the open cholecystectomy the gallbladder can be removed using a minimally invasive procedure known as closed laparoscopic cholecystectomy. The closed laparoscopic cholecustectomy is done by making two to three small incisions in the abdomen through which an insertion of a surgical instrument can be done. The instrument can comprise an illumination means to illuminate surgical area and an imaging device to provide the surgeon with images from inside the body. Despite the advantages of laparoscopic over open cholecystectomy several reports have shown that the incidence of bile duct injuries has raised from a 0.1%-0.2% to 0.4%-0.7%. In 97% the injuries are caused by misidentification of biliary anatomy such as for example the operator mixing up the axial ducts as the cystic duct. Intraoperative cholangiography and ultrasound are standard methods of identifying biliary anatomy at surgery. However, these two techniques carry disadvantages, such as, a high cost, need of highly trained and experienced personal capable to interpret the imaging results, sturdy equipment, radiation hazard, and lack of real-time feedback during the procedure on the biliary anatomy so that the surgeon can make an informed and right decision during the surgery.

Various known prior art teaches the use of an indocyanine green (ICG) dye and an infrared light illumination to achieve an intra-operative visualization of the bile ducts. The main limitation of the known prior art device and method is that the indocyanine green dye is expensive dye and the prior art system requires an additional specialized camera to capture the near-infra-red (NIR) images of the biliary tree thus increasing the cost of the laparoscopic imaging system. In addition to the highly bulky equipment with two cameras, the prior art system also requires an image processing technique in order to improve the image quality.

Accordingly, there is a need for a real-time method that can be integrated with the lapascopy imaging system to identify biliary tree structures during the operation in a user friendly and expedient manner, thus making surgery safer and reducing operating time.

SUMMARY In one aspect, a device is provided for providing an UV excitation light to illuminate a biliary tree or portions thereof for performing laparoscopic cholecystectomy under a visible fluorescence guidance. The system comprises an elongated tubular probe that can be inserted within the incision/opening used for laparscopic instrument insertion.. The tubular probe has an embedded light guide for transmitting UV light and an inner hollow channel for passing a laparscopic instrument through the tubular probe. The system further comprises a light source for producing an excitation light to illuminate the biliary tree or portions thereof and a fluorescent substance injection system to inject the fluorescent substance to an area subject to observation to cause a fluorescence emission in the area, the fluorescent substance being suitable for in vivo use. A produced fluorescence image can be detected by a naked eye or a laparoscopic camera. The light source can be an UV lamp or one or more UV LEDs placed outside the tubular tube configured to produce an UV excitation light that can be focused into the light guide embedded into the tubular probe. In another aspect the light source can be an UV LED mounted at a distal tip of the tubular probe. In addition the device can comprise a position sensor placed at a distal tip of the tubular probe. The position sensor can comprise a vertical shaft projecting downwardly from the tip of the tubular probe and a variable position scale. The position sensor is configured to indicate a distance between the area under observation and the distal tip of the tubular probe. In one aspect the intensity of the produced UV light is reduced or increased based on the distance measured by the sensor to ensure safe and constant dose of UV light. In one aspect, the light source can be configured to produce simultaneously an UV excitation light and a white light. The device can comprise a beam splitter to convey the white light into a fiber optic of the laparoscopic probe and to convey the UV excitation light into the light guide embedded into the tubular probe.

In one aspect, the tubular probe can be reusable after sterilization. In another implementation, the tubular probe can be disposable after use.

In another aspect, a device is provided for imaging a biliary tree or portions thereof. The device can be used as stand-alone laparscopic imaging system comprises an elongated rigid tubular probe having at least two channels, a light guide embedded in a first channel of the tubular probe, a light source configured to produce simultaneously an ultraviolet (UV) excitation light and white light , a fluorescent substance injection system connected to a fluorescence substance source to inject the fluorescent substance to an area subject under observation to cause a fluorescence emission in the area and an imaging device to capture the fluorescence emission coming from the area under observation. The light source can be an array of light emitting diodes (LEDs). At least one of the LEDs is an UV LED to produce an UV excitation light. The device further comprises an optical coupler to combine the excitation light and the white light and to transmit the combined light to the light guide embedded in the tubular tube. A second channel of the tubular probe is made of an imaging fiber bundles and is used to transmit the white light image and the fluorescense image to a color video camera mounted at the distal end of the second channel.. The device further comprises a long pass filter located in front of the imaging device to pass a light longer than 400 nm to the imaging device and to reflect a light less than a 400nm away from the imaging device.. The array of LEDs can produce an illumination light in a wave range of 350- 700nm. In yet another aspect, a diagnostic imaging method for visualizing a biliary tree or portions thereof is provided that includes the steps of injecting a fluorescent substance suitable for an in vivo use, the fluorescent substance emitting photons when exposed to an excitation light, illuminating all or a portions of the biliary tree with an ultraviolet excitation light and observing locations of emission from a bile, wherein the emissions of the bile provide a fluorescence image of the biliary tree or exposed portions thereof. A fluorescence image can be observed with a naked eye during an open cholecystectomy or through a laparoscopic camera.

In addition to the aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and study of the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers may be re-used to indicate correspondence between referenced elements. The drawings are provided to illustrate example embodiments described herein and are not intended to limit the scope of the disclosure. Sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not drawn to scale, and some of these elements are arbitrarily enlarged and positioned to improve drawing legibility.

FIGURE 1 is a schematic cross-sectional view of a device for visualizing a biliary tree using a fluorescence emission from a fluorescent dye injected into an observation area according to one non-limiting embodiment showing a light guide embedded into the tubular probe and the inner hollow channel for inserting surgical instrument .

FIGURE 2 is a schematic cross-sectional view of a device for visualizing a biliary tree showing a light source mounted on a tip of a tubular probe and a surgical instrument inserted into an inner channel of the tubular probe.

FIGURE 3 is a schematic cross-sectional view of a device for visualizing a biliary tree according to one non-limiting embodiment showing an optical beam splitter used to convey a white illumination light to a laparoscopic fiber optic and to convey an excitation light to a light guide embedded into the tubular probe. FIGURE 4 is a schematic cross-sectional view of a device for visualizing a biliary tree according to one non-limiting embodiment showing a probe positioning sensor at a tip of a tubular probe.

FIGURE 5 is a schematic device for visualizing a biliary tree according to one non-limiting embodiment that can be used as a stand-alone imaging probe.

FIGURE 6 is a schematic cross-sectional view of a possible tubular probe design and layout.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The present invention relates to a device and a method for visualization of luminal structures such as bile ducts, blood vessels, urethras, lymphatic vessels etc. and/or tissue perfusion, by producing real-time fluorescence emission from the luminal structures. The device can be inserted through a laparoscopic opening or through an open surgery incision and can provide simultaneous visualization and dissection of the bile duct structures under fluorescence guidance during the cholecystectomy procedure. The device can be used as a stand-alone device or can be integrated to a laparoscopic probe. The invention is based on injecting a fluorescein dye (or any other suitable fluorescent dye) and illuminating the area surrounding where the dye has been injected with an ultraviolet (UV) excitation light. The UV light and the injected dye will produce a fluorescence image from internal structures of the biliary tree that can be detected using regular video camera or with a naked eye. An UV light of 350 - 400nm can be transmitted to the area under observation through a laparoscopic probe, or through the open surgery incision. The fluorescent dye can be injected in the observation area for emitting fluorescence when the area is irradiated with the UV excitation light. The illumination light can have intensity (power density) sufficient to induce fluorescence emission in the area injected with the fluorescein. The irradiated UV light should be within the standards allowed by the Maximum Permissible Dose (MPD) for tissues. The fluorescein can be injected either intravenously or directly to the gallbladder during the open cholecystectomy procedure. The device can be integrated to a standard laparoscopic probe. It can be inserted through an instrument channel (instrument trocar) of the laparoscopic probe. The UV light can be with a constant power density regardless of the distance between a tip of the probe and the observation area and can be strong enough to produce visible fluorescence emission from the biliary tree that is injected with a suitable fluorescent dye without causing damages to the area.

In one implementation, the device can be used as a stand-alone imaging device without employing a standard laparoscopic probe.

1. To provide an overall understanding of the invention, certain illustrative embodiments will be described, including a device for generating real-time fluorescence of the biliary tree structure used during laparoscopic or open cholecystectomy procedures. However, it will be understood that the methods and systems described herein can be suitably adapted to other medical imaging applications where fluorescence images with diagnostic image information obtained from the image can be acquired. For example, the systems and methods are applicable to a wide range of diagnostic or surgical applications where a target pathology, tissue type, or cell may be labeled with a fluorescent dye. For example, the device can be used to detect ischaemic tissues in the deeper tissues and body cavities at surgery, e.g., ischaemic intestine, vascularity of anastomoses, Assessment of viability of pancreas for acute pancreatitis (detect necrotic areas) and first stage Fowler Stevens op for undescended testis. Or to check the perfusion of transplanted organs at operation, e.g., kidney and liver. These and other applications of the devices described herein are intended to fall within the scope of the invention.

FIG. 1 shows one non-limiting embodiment of a device 10 of the present invention. The device 10 can comprise an elongated tube 12, and a light source 14. The tube 12 can have a rigid cylindrical body with at least two separate channels 11a and l ib. A light guide 16 can be embedded into a first channel 11a of the tube 12. The light guide 16 can be used for transmitting an illumination light from the light source 14 to an area under observation 18. A second channel l ib can be hollow. The second channel l ib of the tube 12 can be used to insert a surgical instrument used during cholecystectomy such as an electrocautery. In one implementation, different shapes of the tube 12 can be used as long as the tube 12 is sized and shaped suitably for inserting into a surgery incision or into an instrument insertion channel (trocar) during laparoscopic procedure . The device 10 can further include an injection means 20 for injecting a fluoresce material to the area 18. The injection means 20 can comprise a dye source 22 containing the fluorescence material and an injector 23 connected to the dye source 22 to inject the dye to the area 18. The injector 23 can inject the fluorescent dye to the area 18 either directly through the surgical opening or intravenously. The fluorescence material can be a fluorescein or any other suitable fluorescent dye. The fluorescence dye can be configured to emit photons when excited with an ultra violet or blue excitation light.

The tube 12 can be dimensioned and sized so that it can be inserted into surgery incision. For example, the tube 12 can have a length of about 15 - 35mm and a diameter of about 15mm or less. A diameter of the first channel 11a can be around 5 mm or less and_a diameter of the second channel 1 lb can be suitable for inserting a 5mm or 10mm surgical instrument into it.

The light source 14 can be an UV lamp used for irradiating the area 18 with an ultraviolet excitation light of about 360 - 400nm. The light source 14 can produce shorter or longer waveband of the excitation light without departing from the scope of invention. For example, the light source 14 can produce an excitation light of about 350 - 400nm. In one implementation, the light source can be one or more light emitting diodes (LEDs) configured to produce an UV excitation light. The light source 14 can be located outside the tube 12 and a number of light collection means, e.g. collection lenses, can be used to focus the illumination light into the light guide 16. The light guide 16 can be an UV transmitting quartz glass. In one implementation, the light guide 16 can be a liquid light guide. The fluorescent dye can be introduced from the dye source 22, through the injector 23 into the bloodstream of a subject. In one embodiment the fluorescent dye can be injected in the area 18 directly through the surgery incision. When an area where the fluorescent dye has been injected is illuminated with the ultraviolet excitation light, the fluorescent dye emits photons producing a fluorescence. The fluorescence light emitted from the area 18 (due to the fluorescent dye injected therein) can be collected by one or more lenses (not shown) that can focus the emitted fluorescence into an imaging guide. The image guide can be the same as the light guide 16 or can be separate light guide independent from the light guide 16. The device 10 can be integrated to the laparoscopic probe (not shown) by inserting the tube 12 through the instrument channel (trocar) of such probe. In this case the emitted fluorescence can be focused into an image guide of the laparoscopic probe. The fluorescence image can be observed with a naked eye 24 in case when the device 10 is used during an open surgical procedure or can be detected by an image detector 26. The fluoresce image captured by the detector 26 can be displayed to a monitor 28. The image detector 26 can be a standard camera used in any commercially available laparoscopic system. The captured fluorescence image is a visible fluoresce in a green waveband.

The device 10 can further comprise a light source driver/controller that can regulate and control the light source 14 so that the power/energy density of the light source 14 is fixed depending on a distance between a distal tip 12a of the device 10 and the area 18 (tissue under examination). The second channel l ib of the tube 12 can be used for inserting a surgical instrument 13 (FIG. 2) that is typically used during cholecystectomy procedure. The device 10 can further comprise a long pass edge filter 30 located before the image detector 26 to prevent the reflected UV/blue light to reach the detector 26 thus improving the contrast of the fluorescence image.

FIG. 2 shows another non-limiting embodiment of the present invention. The device 10 depicted in FIG. 2 can use one or more UV LEDs 31to generate the excitation light. The one or more LEDs can be mounted at the distal tip 12a of the tube 12 and can generate an UV excitation light with controlled power density to produce a visible fluorescence image of the observation area 18. The fluorescent dye can be injected into the area 18 through an injection system 20 (FIG. 1). The device can further comprise a long pass edge filter 30 located before the image detector 26 so that the light beam reflected and emitted from the illuminated area impinges on the long pass filter 30. The long pass filter 30 is configured to reflect light in an UV/blue wave range, e.g. light with wavelength less than 450nm, and to transmit the light with longer wavelength to the detector 26. So the long pass filter 30 can prevent the reflected UV/blue light to reach the detector 26 thus improving the contrast of the visible fluorescence image. The device 10 depicted in FIG. 2 can be add-on to a laparoscopic system 200 which includes a laparoscopic probe 32. The tube 12 of the system 10 can be inserted into an instrument channel of the laparoscopic probe 32. The image can be captured by a standard laparoscopic camera and can be displayed on the monitor 28 (FIG. 1). In one implementation, the image detector 26 can be a miniaturized charged coupled device (CCD) sensor with filter coating. The CCD can be mounted at the tip 12a of the tube 12. A microlens can be used to focus the fluorescence image onto the CCD sensor. The fluorescence image can be produced by providing the UV excitation light either from an outside light source using a light guide 16 to transmit the illumination light to the area under observation or from one or more LEDs 31 located at the distal tip 12a of the tube 12. FIG. 3 depicts a laparoscopic imaging system 300 where a device for inducing a fluorescence emission is integrated. The system 300 comprises a laparoscopic probe such as a probe 32 and a device 10 shown in FIGs. 1 and 2that can be inserted into an instrument channel of the laparoscopic probe 32. The device 10 can comprise the rigid tubular probe 12 with an inner hollow channel l ib for instrument insertion. The system 300 further comprises a light source 34 for producing simultaneously a white light illumination light and an UV excitation light. The light source 34 can be an array of LEDs that can provide a white light and excitation light in a wavelength of about 350 - 700nm. In one implementation, the light source 34 can be a mercury lamp, a xenon lamp or any other light source that can provide a strong UV excitation light and a white light illumination light. The produced UV excitation light is strong enough to provide fluorescence emission from an area where a suitable fluorescent dye is inserted through a dye injection system (not shown). The system 300 further comprises an optical coupler 36. The optical coupler 36 can comprise a beam splitter (beam combiner) and an ultraviolet (UV) filter. The optical coupler 36 is configured to convey the white illumination light to a fiber optic 33 of the laparoscopic probe 32 and to transmit the UV excitation light to a light guide embedded within the channel 11a of the rigid tube 12. Fluoresce emitted from the area under observation in which the fluorescent dye is injected, can be captured by a standard laparoscopic camera 26. A reflected UV/blue light (less than 400nm) coming from the observation area can be prevented from reaching the camera 26 by inserting a long pass filter 30 that reflects the light less than 400 nm and transmits the light longer than 400 nm to the camera 26 thus improving the contrast of the fluorescence image.

FIG. 4 shows an example of a device 40 for visualization of the biliary tree (similar to the device shown in FIG 2). The device 40 can comprise a LED 42 as a light source for producing an UV excitation light beam. The LED 42 can be mounted at a distal tip of a first channel 1 la of the rigid tubular probe 12. A second hollow channel 1 lb of the tube 12 can be configured to receive a surgical instrument 44. In addition the device 40 can comprise a mechanical valve 46 connected the second channel l ib at a distal end 12c of the tube 12. The valve 46 can prevent a pneumoperitoneum gas that is injected into an abdominal cavity to separate an abdominal wall from its contents, to escape outside the abdominal cavity through the hollow channel 1 lb. The device 40 further comprises a position sensor 48 that comprises a shaft 49 and a variable position scale to indicate a distance between an area under observation 18 and a distal tip 12a of the tube 12. The shaft 49 can be connected in proximity to the distal tip 12a and projects downwardly away from the distance tip 12a. The shaft 49 can slide out of the tube 12 into its expanded form (projecting away from the tube tip 12a) or can be retracted into its close position when the shaft 49 is slide into the tube 12. When in its expanded for the shaft 49 can touch a tissue (area 18) under observation and thus indicate the distance from it on the variable position scale. When not in use the shaft 49 of the sensor 48 can slide into the tube 12. Based on the distance between the area 18 and the distal tip 12a of the tube 12 a power density of the light source 44 can be adjusted. For example, if the tube is close to the area the power density of the light source can be reduced. When the distance between the area 18 and the tip 12a of the tube 12 is increased the power density of the light source can be increased too. The shaft 49 can be made of any suitable material such as a stainless steel and can have a diameter of about l-3mm. A rubber pad is connected to the shaft end to touch the tissue softly. The device 40 is dimensioned to be inserted into an instrument channel of a laparoscopic probe.

In one implementation, the rigid tube 12 of the device shown in FIGs 1 - 4 can be made of a stainless steel or any other material that can withstand a suitable sterilization technique. Such tube 12 can be reusable after sterilization. In another implementation, the tube 12 can be made from a suitable plastic material. Such tube can be disposable after use. The tube 12 can be inserted into an instrument channel of a laparoscopic probe. Then the area/tissue (i.e. a bile duct) is injected with the fluorescent dye such as, a fluorescein. When such area/tissue is illuminated with an UV excitation light the UV light induces the area/tissue to emit fluorescence. Such fluorescence provides visualization of the illuminated area/tissue (i.e. a bile duct or a portion of it) and allows to _^distinguish accurately a bile tree anatomy identifying tissue to be removed. The tissue can be removed using the dissection instrument that can be inserted into the inner hollow channel l ib of the tube 12.

FIG. 5 shows a device 50 for visualization of the biliary tree that can be used as a stand-alone imaging device for performing laparoscopic surgery under fluorescence guidance. The device 50 can comprise an elongated, rigid, tubular body 52, a light source 54 and an image detector 56. The light source 54 can be an array of multiple LEDs. Some LEDs (e.g. 54a) can be an UV LEDs for producing an UV excitation light. The other LEDs (e.g. 54b) can produce a white light illumination beam. An optical coupler 57 can be used to combine an UV excitation beam and a white light beam coming from the array of LEDs 54a and 54b. The white light beam and the excitation beam can be focus by a collecting lens (not shown) into a light guide 58. The light guide 58 can be a liquid light guide or a quartz glass configured to transmit both the UV excitation light and the white light. The light guide 58 can be used to simultaneously transmit the UV light beam and the white light beam to an area under observation 18. For example, the area under observation can be a bile duct or a portion of the bile duct. The area 18 can be injected with a fluorescein or any other suitable fluorescent dye so that when it is illuminated with the UV excitation light the fluorescent dye emits photons producing fluorescence light. Light that is reflected and emitted from the area 18 is collected by a lens (not shown) and can be transmitted through a fiber optic 59 to the detector 56. The image captured by the detector 56 can be displayed on a monitor (not shown). The device 50 can further comprises a long pass filter 60 located before the detector 56. The light coming from the area 18 impinges on the filter 60. Light with a wavelength less than 420nm (UV /Violet reflected light) if reflected while the light longer than 400nm (with green fluorescence) is transmitted to the detector 56. The device 50 can further comprise an instrument channel (not shown) for inserting a surgery instrument.

In one mode of operation, the imaging system 50 is inserted into a laparoscopic incision and the area under examination such as, bile duct, blood vessels, urethras, lymphatic vessels, is illuminated simultaneously with a white light and an UV excitation light. A fluorescent dye such as, a fluorescein or any other suitable fluorescent dye is injected to the area under examination either directly or intravenously. When the area injected with the fluorescent dye is illuminate d with the UV excitation light a fluorescence is induced showing accurately the structural anatomy of the illuminated area. The fluorescent image is captured by the camera 56 and is displayed on the monitor.

Figure 6 shows two modes describing the design and construction of a disposable tubular tube inserted during laparscopy. The tubular tube 3 has two channels 4 and 6. The first channel 6 has embedded UV transmission quartz. The embedded quartz rod is coupled to external UV light through light guide (like liquid light guide) 10. The inner hollow channel 4 is used to mount a disposable trocar for surgical instrument insertion. While particular elements, embodiments and applications of the present disclosure have been shown and described, it will be understood, that the scope of the disclosure is not limited thereto, since modifications can be made by those skilled in the art without departing from the scope of the present disclosure, particularly in light of the foregoing teachings. Thus, for example, in any method or process disclosed herein, the acts or operations making up the method/process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Elements and components can be configured or arranged differently, combined, and/or eliminated in various embodiments. The various features and processes described above may be used independently of one another, or may be combined in various ways. All possible combinations and sub-combinations are intended to fall within the scope of this disclosure. Reference throughout this disclosure to "some embodiments," "an embodiment," or the like, means that a particular feature, structure, step, process, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases "in some embodiments," "in an embodiment," or the like, throughout this disclosure are not necessarily all referring to the same embodiment and may refer to one or more of the same or different embodiments. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, additions, substitutions, equivalents, rearrangements, and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions described herein.

Various aspects and advantages of the embodiments have been described where appropriate. It is to be understood that not necessarily all such aspects or advantages may be achieved in accordance with any particular embodiment. Thus, for example, it should be recognized that the various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may be taught or suggested herein.

Conditional language used herein, such as, among others, "can," "could," "might," "may," "e.g.," and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without operator input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. No single feature or group of features is required for or indispensable to any particular embodiment. The terms "comprising," "including," "having," and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term "or" is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list.

The example calculations, simulations, results, graphs, values, and parameters of the embodiments described herein are intended to illustrate and not to limit the disclosed embodiments. Other embodiments can be configured and/or operated differently than the illustrative examples described herein.

Claims

WHAT IS CALIMED IS:

1. A device for providing an UV excitation light to illuminate a biliary tree or portions thereof and for performing laparoscopic cholecystectomy under a visible fluorescence guidance, the device comprising:

an elongated tubular probe having an inner hollow channel;

a light source for producing an UV excitation light to illuminate the biliary tree or portions thereof; and

a fluorescent substance injection system to inject the fluorescent substance to an area subject to observation, the fluorescent substance being suitable for in vivo use, the fluorescence substance emitting photons in the visible spectra in response to the excitation light.

2. A device of claim 1, being dimensioned to be inserted into an instrument insertion channel (trocar) used during laparoscopy.

3. A device of claim 1, further comprising an imaging device configured to capture a fluorescence image produced when the area injected with the fluorescence substance is illuminated with the UV excitation light.

4. A device of claim 1, wherein the light source is an UV LED mounted at a distal tip of the tubular probe.

5. A device of claim 1, wherein the light source is located outside the tubular probe.

6. A device of claim 1, further comprising a light guide embedded into the tubular probe, the light guide being configured to transmit the UV excitation light from the light source located outside the tubular probe to the area under observation.

7. A device of claim 6, wherein the light guide is a liquid light guide or a UV transmitting quartz glass.

8. A device of claim 1, wherein the light source produces the excitation light in a wavelength of 350 - 400nm.

9. A device of claim 1, further comprising a surgery instrument inserted into the inner hollow channel of the tubular probe.

10. A device of claim 1, wherein the inner hollow channel has a mechanical valve such as flap valve at its distal end to control the passage of the surgical instrument.

11. A device of claim 1, wherein the inner hollow channel of the tubular tube can fit a disposable or reusable laparscopy trocar for surgical instrument insertion

12. A device of claim 3, further comprising a long pass filter located in front of the imaging device, the long pass filter being configured to pass a light longer than 400 nm to the imaging device and to reflect a light less than a 400nm away from the imaging device.

13. A device of claim 1, further comprising a position sensor placed at a distal tip of the tubular probe, the position sensor having a shaft configured to slide out of the distal tip to its expanded position, and a variable position scale, the position sensor being configured to indicate a distance between the area under observation and the distal tip of the tubular probe.

14. A device of claim 1, wherein the tubular probe is disposable after use.

15. A device of claim 10, wherein the tubular probe is reusable.

16. A device for providing simultaneously an UV excitation light and a white light to illuminate an biliary tree or portions thereof and for performing laparoscopic cholecystectomy under a visible fluorescence guidance, the device comprising:

an elongated tubular probe having an inner hollow channel , a light guide embedded into the tubular tube;

a light source for producing simultaneously an UV excitation light and a white light to illuminate the biliary tree or portions thereof; and

a fluorescent substance injection system to inject the fluorescent substance to an area subject to observation, the fluorescent substance being suitable for in vivo use, the fluorescence substance emitting photons in response to the excitation light.

17. A device of claim 16, further comprising an imaging device to capture a fluorescence image of the area under observation.

18. A device of claim 16, being dimensioned to be inserted into an instrument channel of a laparoscopic instruments.

19. A device of claim 16 further comprising an optical coupler to convey the white light from the light source to a fiber optic guide of the laparoscopic probe and to convey the UV excitation light to the light guide embedded into the tubular probe.

20. A device of claim 16, wherein the light guide is a liquid light guide or a UV transmission quartz glass.

21. A device of claim 16, wherein the light source produces light in a wavelength of 350 - 700nm.

22. A device of claim 16, further comprising a long pass filter located in front of the imaging device, the long pass filter being configured to pass a light longer than 400 nm to the imaging device and to reflect a light less than a 400nm away from the imaging device.

23. A device of claim 16, further comprising a position sensor placed at a distal tip of the tubular probe, the position sensor having a shaft configured to slide out of the distal tip to its expanded position, and a variable position scale, the position sensor being configured to indicate a distance between the area under observation and the distal tip of the tubular probe.

24. A device of claim 16, wherein the tubular probe is disposable after use.

25. A device of claim 16, wherein the tubular probe is reusable.

26. A device for imaging a biliary tree or portions thereof, the device comprising: an elongated tubular probe having at least two channels, the tubular probe having a light guide embedded into a first channel of the tubular probe, the light guide being configured to transmit an UV excitation light and a white light;

a light source connected to the tubular probe for producing simultaneously an UV excitation beam and a white light beam, the excitation beam and the white light beam being transmitted through the light guide to an area under observation;

a fluorescent substance injection system to inject the fluorescent substance to an area under observation, the fluorescent substance being suitable for in vivo use, the fluorescence substance emitting photons in response to the excitation beam; and

A video camera connect configured to capture a fluorescence image produced from the area injected with the fluorescent dye.

27. A device of claim 1, wherein the light source is an array of LEDs, at least one of the LEDs is configured to produce an UV excitation light.

28. A device of claim 2, wherein the array of LEDs produces an illumination light in a wavelength of 350 - 700nm.

29. A device of claim 1, further comprising an optical coupler to combine the excitation beam and the white light beam.

30. A device of claim 1, wherein the fluorescence substance is a fluoresceine.

31. A device of claim 1, wherein the light guide is a liquid light guide or a quartz glass.

32. A device of claim 1, further comprising a long pass filter located in front of the imaging device, the long pass filter being configured to pass a light longer than 450 nm to the imaging device and to reflect a light less than a 450nm away from the imaging device.

33. A device of claim 1, further comprising a position sensor connected to a distal tip of the tubular probe, the position sensor having a shaft configured to slide out of the distal tip to its expanded position, and a variable position scale, the position sensor being configured to indicate a distance between the area under observation and the distal tip of the tubular probe.

34. A device of claim 1, further comprising a surgery instrument inserted into a second channel of the tubular probe.

35. A diagnostic imaging method for visualizing a biliary tree or portions thereof, the method comprising the steps of:

injecting a fluorescent substance suitable for an in vivo use, the fluorescent substance emitting photons when exposed to an excitation light; illuminating all or a portions of the biliary tree with an ultraviolet excitation light to stimulate the fluorescent substance to emit photons; and

observing locations of emission from the bile, wherein the emissions of the bile provide an image of the biliary tree or exposed portions thereof.