The present invention related to an apparatus and method for diagnosing diseases inside of a living biological body. A wireless capsule comprises a micro-spectrometer, a biosensor and/or a select specimen collection system and can be introduced into a nature tract of the biological body. The disease information can be acquired during the wireless capsule travels through the biological body.
Wireless capsule means a micro-device, which can travel inside of a living biological body for collecting information to diagnose diseases and/or collecting specimen. Spectroscopy means a technique of measuring an optical property distribution or a concentration from a biological tissue and/or juice to diagnose disease via its morphology and/or chemical component changes. Biosensor means a self-contained integrated device, which is capable of providing specific analytical information using a biological recognition element.
One of the primary benefits of the photonic approach to imaging and examining biological materials is that said imaging and examination can be conducted in vivo in a patient with little risk of injury to the patient. This is to be contrasted with certain conventional imaging techniques, such as X-ray imaging, which involves subjecting a patient to potentially harmful X-ray radiation, and with certain conventional examination techniques, such as biopsy and histological evaluation, which cannot be conducted in vivo. The organ or tissue to be examined is located internally. The photonic examination approach often involves inserting optical fibers, typically disposed within an endoscope or similar device, into the patient's body in proximity to the area to be examined. The area to be examined is irradiated with light transmitted thereto by optical fibers, and the light from the irradiated area is collected and transmitted by optical fibers to a spectroscopic device or camera and computer for observation and analysis.
Over the past twenty years, many researchers have laid down a strong foundation to apply optical spectroscopy for disease diagnosis or blood information in laboratory bench scales. Examples of spectroscopy diagnoses are: Chance in U.S. Pat. No. 5,987,351 “Optical coupler for in vivo examination of biological tissue”, Alfano et al. in U.S. Pat. No. 6,615,068 “Technique for examining biological materials using diffuse reflectance spectroscopy and the kubelka-munk function”, Alfano et al. in U.S. Pat. No. 6,208,886 “Non-linear optical tomography of turbid media”, Alfano et al. in U.S. Pat. No. 6,091,985 “Detection of cancer and precancerous conditions in tissues and/or cells using native fluorescence excitation spectroscopy”, Georgakoudi et al in U.S. patent application No. 20030013973 “System and methods of fluorescence, reflectance and light scattering spectroscopy for measuring tissue characteristics”. Examples of methods in hemoglobin diagnosis are Schmitt, et al., in the “Measurement of Blood Hematocrit by Dual-wavelength Near-IR Photoplethysmography,” in SPIE proceedings in 1992 and Sodickson's “Kromoscopic Analysis: A Possible alternative to spectroscopic analysis for noninvasive measurement of analytes in vivo” in Clinical Chemistry magazine in 1994. These spectroscopic studies will be adapted with today's system integration technologies in our wireless spectroscopy biopsy capsule invention.
Optical spectroscopy from a tissue sample has been used in pathology to determine the disease in laboratory. With the advancement of today's photonic technology, broad-specttum light sources of laser diodes and LED (light emitting diode) are readily available and can be coupled into a mini-scale sensor or capsule. These broad spectrum and compact light sources can be configured and utilized with a variety of different fluorescence or absorption or diffuse reflect spectra. One or differing excitation wavelengths can be used in these approaches. The chemical and biological threats are detected and identified through interactions between the light and the matter.
A wireless capsule can be used to collect gastrointestinal (GI) tract tissue samples or other specimen of patients using special designed devices. The capsule comprises one or multiple LEDs, one or multiple optical information filter modules, one or multiple optical sensors, a signal-processing module, and a data storage module. The filter module is often coated on the surface of the optical sensor. The spectroscopy can also be used to measure the physiological and/or biochemical parameters in tissues and juices of a biological body, such as pH, osmolarity, temperature, ion concentrations, SaO2, SaCO2 hemoglobin, glucose, cholesterol, cholesterol esters, lipoproteins, triglyceride of changes in optical characteristic to diagnose the disease.
Alfano, R. et al. in U.S. Pat. No. 6,240,312 “Remote-controllable, micro-scale device for use in medical diagnosis and/or treatment”, revealed some basic concepts using spectroscopic diagnosis in a wireless capsule. They did not provide detail designs and methods such as biosensors or sample collection methods. Kim, et al in U.S. patent application No. 20030092964 “Micro capsule type robot” and Kimchy, et al in U.S. patent application No. 20030139661 “Ingestible device”, were aiming on the mechanical and optical designs of a wireless capsule.
One development of mini-scale sensors is the biosensor, which behaves as a miniature bio-probe and data processor. Biological data of the tissue sample can be analyzed either in vivo or in vitro (after the biosensor is discharged from the anus). A biosensor can be used to detect biomarkers, such as hepatocarcinoma-intestine-pancreas/pancreatitis-associated-protein I (HIP/PAP-I) in pancreatic juice for early diagnosis of pancreatic adenocarcinoma; the dyed antibody of p53 tumor suppressor gene in the GI wall for diagnosing the cancers; or any dye-marked target which has an optical characteristic. A biosensor can also be used to measure the physiological and/or biochemical parameters in GI juices, such as cholecystokinin-(26-33) (CCK-8), special proteins, and some changes in optical properties of GI tissues or GI juices for diagnosing disease and criticizing the GI physiological conditions.
It is an object of the present invention to provide a novel medical diagnosis tool that combines wireless capsule with micro-spectroscopy to detect morphology and/or chemical component changes inside a biological body in vivo.
It is an object of the present invention to provide a novel medical diagnosis tool that combines a wireless capsule with micro-biosensor to detect changes in DNAs, proteins, enzymes and antibodies inside a biological body in vivo.
It is an object of the present invention to provide a novel medical diagnosis tool that can collect one or multiple specimens inside a biological body guided by the information from micro-spectroscopy and/or micro-biosensor in vivo.
It is another object of the present invention to provide a novel medical diagnosis tool that combine one or multiple techniques described above to provide a multiple functional wireless capsule for medical uses.
As a result of extensive devolvement in order to achieve the above objects, the inventors further developed the above knowledge found by the inventors, and discovered that the above objects were accomplished by
All of which are incorporated herein by reference.
This invention will integrate technologies of miniature light sources, light detector, biosensor, and remote sample collection, using disease sensitizing agents, optical spectroscopy and imaging to build a wireless capsule for non- or mini-invasive medical diagnoses.
The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.
The accompanying drawings, which are hereby incorporated into and constitute a part of this specification, illustrate preferred embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings wherein like reference numerals represent like parts:
The principles and preferred embodiments of the present invention is a wireless capsule. A schematic diagram of a wireless capsule for spectroscopic biopsy is shown in
The wireless capsule adapted for use inside a biological body will be a capsule without a wire connection, but with or without a remote-control system outside the body. It will be 1 mm to 30 mm in length, 1 mm to 15 mm in wide or in diameter and a form as a cylinder or any other form. It comprises of
The heart of the spectroscopy biopsy capsule is a micro-spectrometer. A design block diagram of a micro-spectrometer is shown in
The wireless capsule consists of a specimen collection system, a spectroscopic system (comprising, for example, fluorescence-type and/or transmission-type and/or reflection-type gratings and filters), a motion mechanism, a communications system, a light source, an imaging system and a power system. A flow chart of the spectroscopic wireless capsule design is shown in
The foregoing devices can measure local tissue properties in situ using spectroscopic features from fluorescence, transmission, differ reflectance, scattering, and Raman bands. Two specific examples to detect GI bleeding and cancer are described below:
GI Bleeding Detection using Absorption Spectroscopy A wireless capsule comprises of a light emitting and light detecting parts as shown in
Both spectral and position data will be transmitted to a receiver belt worn on the human body. The final diagnosis will be performed by a computer system to compare the ratio of oxyhemoglobin and de-oxyhemoglobin concentrations. The maximum oxygenation value will reveal the bleeding area. Alternatively, a specimen storage module inside the capsule can save physically biopsy samples to be analyzed after the capsule is excreted from anus.
Cancer Diagnosis using Fluorescence Spectroscopy A wireless capsule can be designed for fluorescence spectroscopy. Major parts in this application include one or multiple light emitting diodes at different wavelengths and one or multiple photo detectors with selected wavelength narrow band filters as shown in
Other examples of using fluorescence spectroscopy to diagnose cancer are given by Alfano and co-workers using biopsy specimen in laboratory. Fluorescence spectra of normal tissues excited by 488 nm light were found to be quite different from that of cancer tissues. The emission spectra from cancer tissues have a smooth spectral curve with the peak at approximately 530 nm. The emission spectra from normal tissues have three peaks, at 530, 550, and 590 nm.
Operation procedures of using a wireless capsule to medical diagnosis is typically initiated through a native open such as through mouth by swallowing. It can also be launched from an endoscope, such as from a gastroscope into GI track and a cystoscope into bladder and urinary tract. After identified problems in GI tracts using a wireless imaging capsule, the second capsule is designed as a claim to collect diagnosis sample from the imaged location.
Procedures of capsule biopsy are described as follows:
The solid tissue collection assembly has capabilities to adjust capsule position and azimuth status. Some components designed for the solid tissue specimen collection in a wireless capsule are shown in FIGS. 6 to 8 These parts include:
Liquid specimen collection can be performed using various methods, such as needles, reverse osmosis, permeation, porous structure, fiber structure, and hollow fibers.
Optical system for illumination and signal collection uses a multi-lens-mirror imaging assembly for the spectroscopy wireless capsule. The assembly consists of lenses, mirrors, LEDs, apertures, filters, and holders. The detection assembly uses either CCD or CMOS imaging chip.
The first type is a combination of four sets of front-lens, side-lens, mirror, and rear-lens structure. The side view and the A-A′ cross-section view are shown in
The second type is a combination of four sets of front-lens, mirror, and side-lens structure. The side view and the A-A′ cross-section view are shown in
Mirrors are optical reflection surfaces with positive, negative or zero curvature, i.e., concave, convex, or plane reflection surface. LED spectrum covers from the infrared to UV band. The combination of a front lens and the front surface of the optical shell can increase the field of view of imaging. A CCD chip or a CMOS chip is shared by five independent sets of imaging optics, including one wide-angle front imaging and four side high resolution imaging mechanisms.
The light source is preferably one or more micro-scale, color LEDs, lasers based on quantum wells or a photographic flash lamp. The combination two to three LEDs using a hologram can form a wideband light source with a controlled spectral intensity distribution. A combined uv LEDs (wavelength from 250-nm to 350-nm) with white light source will be used in bio-sensor applications inside a wireless capsule.
Optical detectors used in this invention for spectroscopy can be: a CCD or a CMOS chip with the pixel number from 10×10 to 4000×4000 and the spectral spanned from 300-nm to 1100-nm; a NIR camera with the pixels number from 10×10to 2000×2000 and the spectral sensitivity from 400-nm to 1800-nm. For one-dimensional detectors: PIN diode with spectral range from 300-nm to 1800-nm; or APD with spectral range from 300-nm to 1800-nm. Three examples of the position of light source and detector are shown in
A hologram can perform several functions together: multi-function lenses, color filters, spectral reformer, and beam splitter. For the lens application using a hologram, light can be collimated to illuminate the specimen. An example of the holographic multi-function design is shown in
A spectral reformer can adjust the intensity spectral distribution of the illumination to match white light spectrum, Mercury arc spectrum, or sun light spectrum. A holographic beam splitter can provide high throughput efficiency for the illumination light transmission and the signal light reflection based on the geometrical factor and wavelength. By rotating a hologram, tunable narrow band filtering is obtained. This change of the effective grating space will be used as a re-configurable narrow band color filter for signal collection.
For the spectral reformer, the spectral intensity distribution could be determined using the following equation:
I[output, λ]=A1I1(λ1±Δλ1)+A2I2(λ2±Δλ2)+ . . . +AiIi(λi±Δλi)+ . . . +AnIn(λn±Δλn)
Where A1,A2 , . . . Ai, . . . An are constant parameters and could be numerically optimized to fit the desired spectral intensity distribution; Ii is the intensity of the i-th light source at the peak wavelength of λI with the bandwidth of ΔλI, respectively.
After introduced into the inside of a biological body, the wireless capsule will function as a diagnosis modality. Besides two examples shown in
The other examples of detecting optical properties changes of solid tissue or juice in GI tract is that optical absorption spectra can be recorded simultaneously and continuously in the pancreas arterially perfused at various flow rates. This is done to explain how optical absorbance changes corresponding to parallel reduction of cytochromes aa3, b, and cc1 are observed in perfused pancreas stimulated with high concentration of an exocrine secretagogue, such as cholecystokinin-(26-33) (CCK-8). With perfusion flow rate between 1.5 and 3.0 ml/min, there are no optical absorbance changes corresponding to cytochrome reduction, but these optical absorbance changes occur when the perfusion flow rate is decreased to 1.0 ml/min. These optical absorbance changes are not observed during exocrine secretion stimulated by CCK-8 at the perfusion flow rate of 3.0 ml/min.
Transient but a slight change in optical absorbance, which corresponds to reduction of cytochromes, is observed in the glands perfused at the flow rate of 2.0 ml/min when secretion is stimulated by 1 nM CCK-8. When the perfusion flow rate is decreased to 1.0-1.5 ml/min, these optical absorbance changes corresponding to reduction of cytochromes occurred in glands stimulated by CCK-8. Optical absorbance changes corresponding to reduction of mitochondrial cytochromes during secretion stimulated with CCK-8 may indicate local hypoxia in the perfused organ.
Other examples of tissue and/or juice optical property measurements for clinical diagnosis are listed in Table 2 below:
Light-induced fluorescence of exogenous fluorophores can be performed using a wireless biopsy capsule. An example of this application is injecting photofrin as a photosensitized dye into living body 48 h before spectroscopy. The wireless capsule will be inserted into the bladder via a cystoscope. Fluorescence was taken and a ratio of red photosensitized dye fluorescence to the blue auto-fluorescence of the tissue will be calculated. Based upon this ratio, excellent demarcation between papillary tumors and normal bladder wall will be achieved.
Swallow sensitized dyes for in vivo capsule biopsy in GI tract disease and/or functions. The examination using a wireless capsule can be performed in a physician's office or in a hospital. The methods of providing dye include swallow, IM injection, IV injection, and local inunctions. The wireless capsule can be introduced into the native track of the biological body through swallow, injection or an endoscope. For example: the wireless capsule can be swallowed into the GI track via mouth; can be shot into the cardiovascular system via percutanous injection; and can be inserted into the bladder via a cystoscope.
Examples of different spectroscopy with exogenous dyes for clinical diagnoses are listed in Table 3:
Biosensor technology is also coupled into this biopsy capsule invention. The publication of Jin, et al. “Voltage sensitive dye imaging of population neuronal activity in cortical tissue,” in J. Neuroscience Methods in 2002 provides a good example of the voltage enhanced dye imaging approach. Sadoulet's article in the magazine of Biophotonics International “Using light to read the code of life”, in 2003 gave a good review of those miniature spectrometer technology. McMullin, et al. in “Optical Detection System for biosensors using Plastic Fiber Optics” (2003), Thrush et al. in “Integrated semiconductor fluorescent detection system for biosensor and biomedical applications,” (2003) and Ting, et al. in “Research and development of biosensor technologies in Taiwan,” (2000) have provided the design and integration of biosensors with various optical technologies.
Fast and sensitive detection of K-ras mutations in tumor cells of GI tracts are attractive targets for molecular screening and early detection of colon or pancreatic malignancies. Using a biosensor and an optical transducer could be performed.
An example of chemi-luminescence (CE) detection in a flow-thru wireless capsule in vivo can increase both the sensitivity and spatial. Enzyme-catalyzed CL reactions for the detection of hybridizations can be imaged using a CCD camera. Similar to two-color fluorescence measurements, multiple enzyme labels can be used. Relaxation time of a CL species can be applied.
Alterations in the gene have been associated with carcinogenic manifestations in several tissue types in humans. The design of this highly integrated detector system is based on miniaturized phototransistors having multiple optical sensing elements, amplifiers, discriminators, and logic circuitry in a wireless capsule. The system utilizes laser or LED excitation and fluorescence signals to detect complex formation between the p53 monoclonal antibody and the p53 antigen. Recognition antibodies are immobilized on a nylon membrane platform and incubated in solutions containing antigens labeled with Cy5, a fluorescent cyanine dye. Subsequently, this membrane is placed on the detection platform of the biosensor and fluorescence signal is induced using a 632.8-nm He—Ne laser or LED. Using this immuno-biosensor, we have been able to detect binding of the p53 monoclonal antibody to the human p53 cancer protein in biological matrices. The performance of the integrated phototransistors and amplifier circuits of the biosensor, previously evaluated through measurement of the signal output response for various concentrations of fluorescein-labeled molecules, have illustrated the linearity of the microchip necessary for quantitative analysis. The design of this wireless capsule permits sensitive, selective and direct measurements of a variety of antigen-antibody formations at very low concentrations.
Other examples of biosensor diagnoses are listed in Table 4 below:
Specimen collection system in the wireless capsule is described as: The biomarkers of pancreatic adenocarcinoma improve the early detection of this deadly disease to screen for differentially expressed proteins in pancreatic juice (Cancer Res 2002 Mar. 15; 62(6):1868-75, Rosty C, et al.). Pancreatic juice samples can be obtained from patients via a sallow-able wireless capsule. The differentially expressed protein as hepatocarcinoma-intestine-pancreas/pancreatitis-associated-protein I (HIP/PAP-I), a protein released from pancreatic tract during acute pancreatitis and over expressed in hepatocellular carcinoma.
Another application using the specimen collection system is for the pharmaceutical and pharmacological study. The wireless capsule can collect specific specimen from a specific region, e.g. gastric juice in the stomach and pancreatic juice in the duodenum. The collection procedure can be programmed by a microprocessor inside the wireless capsule. The collection can also be performed by a feedback from the spectroscopy or biosensor inside the wireless capsule or by an external trigger signal from outside the human body.
Number | Date | Country | |
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60437022 | Dec 2002 | US |