DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Reference is now made to the drawings wherein like numerals refer to like parts throughout.

[0038] As used herein, the term “autonomously” shall mean independent of direct physical or tactile control by an operator or external device. As will be described in greater detail below, the smart probe of the present invention is designed to be initially introduced into the patient after which time the probe operates autonomously; i.e., only utilizing electrical, inductive, magnetic, or radio frequency signals to enable or perform certain desired functions, with no direct external physical contact or connections. This is to be distinguished from prior art endoscopic inspection or treatment devices, which always maintain some physical or tactile link (such a tube, electrical wire, or fiber optic bundle) with the operator, and hence which do not operate autonomously while in the patient.

[0039] FIG. 3 is a perspective view of a first embodiment of the smart probe of the present invention. The probe 300 comprises an outer housing 302 having a generally ellipsoid shape and an inner cavity 303 (not shown), a lens aperture 304 positioned in one end of the housing 302 , and lenses 306 a, 306 b mounted in alignment with the aperture 304 within a lens retaining board 305 . An optional lens cover 308 covers the lenses 306 a , 306 b and seals the aperture 304 . A plurality of other components (including, inter alia, a CCD array, microcontroller, clock, parallel/serial drivers, and sample and hold circuitry, not shown) are disposed within the aforementioned cavity 303 or otherwise within the outer housing 302 itself. These other components are described in greater detail below with reference to FIGS. 6 - 7 . A generally ellipsoid shape is used for the outer housing 302 of the present embodiment to facilitate passage of the probe 300 through the intestinal tract of the patient, and to assist in maintaining the proper orientation of the probe during use; e.g., such that the lenses 306 are oriented to have sufficient perspective and focal length to adequately view portions of the interior of the patient's intestine. Optionally, the rear portion of the probe 300 may be flared, or other contours or devices utilized to assist in orientation within the intestine. While the present embodiment utilizes a generally ellipsoid shape for the outer housing 302 , it will be recognized that other shapes and configurations for the outer housing (and lens aperture 304 ) may be used in accordance with the present invention. For example, substantially cylindrical or “bullet-shaped” outer housings could be used. Alternatively, an outer housing having a non-symmetric lateral cross-section (i.e., that taken in a plane to which the longitudinal axis of the housing 302 is normal) could be employed. Many other suitable shapes exist.

[0040] Furthermore, it will be recognized that the probe 300 may operate in both a “forward looking” and “rearward looking” orientation within the patient. Specifically, the probe may be disposed within the intestine such that the aperture 304 (and associated CCD array) is oriented in the direction of probe advance, or alternatively rearward. As described in more detail below, it is further contemplated by the present invention that the probe may be equipped with both forward and rearward looking CCD arrays.

[0041] The outer housing 302 is sized in the present embodiment to have a diameter (at its widest point, measured across its circumference) on the order of 12 mm (roughly 0.5 in.) in order to allow unencumbered passage through the intestinal tract and even the ileocecal valve. However, it will be appreciated that other sizes of probe, both smaller and larger, may be used depending on a variety of factors including the size of, and any peculiarities associated with, a given patient's intestines, as well as the instrumentation/components desired to be carried by the probe 300 .

[0042] The outer housing 302 is in the present embodiment constructed of a mechanically rigid and stable polymer such as ethylene tetrafluoroethylene (Tefzel®) which is also resistant to chemical exposure and other environmental influences, and which is also nontoxic to the patient. Tefzel® also has the desirable property of being able to be fabricated with a smooth (i.e., low coefficient of friction) surface which further facilitates passage of the probe 300 through the intestinal tract, although this property is not essential. It can be appreciated, however, that other materials (such as certain metals, resins, composites, or even organic materials) may be used to form all or part of the outer housing 302 . For example, the housing need not be a discrete component, but rather may be an encapsulant such as that used on integrated circuit devices.

[0043] The housing 302 is made of minimal wall thickness so as to have adequate rigidity yet permit the maximum size cavity therein. In the present embodiment, a wall thickness of 0.5 mm (roughly 0.020 in.) is selected, although other values may be used. The outer housing of the probe of FIG. 3 is split circumferentially at the mid-section to facilitate component insertion and removal. The halves of the housing 302 a, 302 b are fit tightly together so as to minimize the possibility of fluid leaking into the cavity 303 . A sealing agent 580 (and/or a sealing ring or gasket) is used to further prevent fluid leakage. Note also that such sealing is applied around the interface of the lens board 305 and the outer housing 302 , as shown in FIG. 5 .

[0044] One or more data transfer terminals 532 and power transfer terminals 716 are embedded at or near the surface of the probe housing 302 to facilitate data and power transfer, respectively, between the probe 300 and the MCD 800 ( FIG. 8 ). In the present embodiment, the terminals 532 , 716 are ring-shaped so as to permit data/power transfer in any rotational orientation of the probe 300 around its longitudinal axis; however, it will be recognized that other terminal shapes and configurations may be used.

[0045] The lens cover 308 shown in FIG. 3 is designed to protect the lenses 306 a, 306 b , 306 c from becoming occluded by substances present in the intestine of the patient during probe travel. Ideally, the patient will be restricted from eating or ingesting any substance for a suitable period prior to probe use so as to minimize any such occlusions; however, the lens cover 308 further assists in maintaining the lenses clear prior to use. The lens cover 308 of the present embodiment is a thin membrane (on the order of a few thousandths of an inch thick) and is comprised of a substantially clear gelatin-like substance comparable to that commonly used to contain and deliver pharmaceutical products (such as so-called “gel caps” which are well known in the pharmaceutical arts) or equivalent thereof. The design and composition of the lens gel substance is, in the present embodiment, controlled so as to provide a timed dissolution within the patient. For example, if it is estimated that the intestinal motility of the patient is X cm/hr, and the region of the intestine desired to be inspected using the probe 300 is Y cm from the point of introduction of the probe, then the lens cover 308 can be chosen to dissolve in roughly Y/X hr or less (allowing for some margin of error). The lens cover 308 of the present embodiment is shaped to conform roughly with the outer surface of the lens(es) 306 and with the profile of the outer housing 302 such that the cover 308 is maintained within the housing aperture 304 , and provides minimal optical distortion, until it dissolves. Note also that a substantially clear material is chosen to permit the passage of some light through the cover 308 before its dissolution, although lens covers with other optical properties (such as selective wavelength filtration) may be used.

[0046] It should be noted that while the present embodiment makes use of a lens cover 308 , the use of such cover may not be necessary in certain applications, and therefore need not be present. Furthermore, while the present embodiment describes a lens cover which is chemically dissolvable, other types of lens covers may be employed with the present invention. For example, a mechanical shutter arrangement could be used to selectively cover/uncover the lenses 306 . Alternatively, a lens cover which dissolves or otherwise alters its properties when exposed to an electrical current or coherent electromagnetic radiation may be employed. A permanent (i.e., non-dissolving) lens cover having desirable optical properties could also be used.

[0047] Referring now to FIG. 4, a front view of the smart probe 300 of FIG. 3 is shown, illustrating the relationship of the housing aperture 304 , lenses 306 , the CCD array 402 , and the lens cover 308 . Specifically, the aperture 304 is sized and shaped to permit light of varying wavelengths to impinge upon the active region 404 of the CCD array 402 , and to accommodate the optical light lens 306 b which is positioned laterally to the main lens 306 a in this embodiment. The aforementioned lens cover 308 generally conforms to the outer surface of each of the lenses 306 a, 306 b, thereby acting as a protective cover for each before dissolution. As will be described in greater detail herein, the optical lens 306 b acts to transfer and distribute broad spectrum visible light generated within the probe 300 to intestinal tissue in proximity to the lenses. Remitted or reflected visible is passed through the main lens 306 a (which is chosen to be effectively transparent to a broad range of wavelengths in the spectral regions of interest) to the CCD array 402 . The main lens 306 is, in the embodiment of FIGS. 3 and 4 , a substantially convex lens designed to gather and more narrowly focus energy originating from various positions outside the probe 300 onto the CCD array 402 . The optical lens 306 b is, conversely, designed to radiate and distribute light incident on its inner surfaces (via the associated fiber optic bundle, described below) more broadly within the intestine.

[0048] The CCD array 402 of the present embodiment is a multi-pixel semi-conductive device having anti-blooming protection, and being sensitive to various wavelengths of electromagnetic radiation. A Texas Instruments Model TC210 192×165 pixel CCD image sensor is chosen for use in the present embodiment, based on its performance attributes, spectral responsivity, and size (i.e., the package outline is roughly 5 mm by 3 mm), although myriad other devices could be used with equal success. The operation of the CCD array 402 is described in greater detail below.

[0049] Referring now to FIGS. 5 and 5 a, cross-sections of the probe 300 of FIGS. 3 and 4 are illustrated. The probe outer housing 302 generally contains a number of different components in its internal cavity 303 including the aforementioned lenses 306 and CCD array 402 , as well as a light emitting diode (LED) 504 , a single mode fiber optic bundle 506 , and one or more inductive data transfer terminals 532 . A number of discrete or integrated semiconductor components are also present within the probe 300 , including a “flash” analog-to-digital converter ADC 512 , sample and hold circuit 514 , parallel and serial drivers 516 , 518 , microcontroller (or microprocessor) 520 , clock driver 524 , and a data interface circuit 526 as described in greater detail below. The LED 504 is located roughly co-linearly with the central axis of its lens 306 b with the fiber optic bundle 508 disposed there between as shown in FIG. 5 . The LED 504 , its fiber optic bundle 508 , and its lens 30 b are optically coupled so as to transmit light energy to the lens in an efficient manner. The A/D converter 512 , drivers 516 , 518 , microcontroller 520 , and other electronic components are disposed within the cavity 303 on one or more miniature printed circuit board assemblies (PCBAs) 510 in a space-efficient manner, with the semiconductor components being disposed and electrically connected on either side of the assemblies 510 . The semiconductor packages are chosen so as to fit within the housing, as discussed in more detail herein. One or more inductive data transfer terminals 532 generally in the form of circumferential rings are disposed within the outer housing at or near the surface thereof as previously described in order to provide for data transfer between the probe 300 and the remote unit 802 of the MCD data processing and analysis equipment 800 external to the patient (see discussion of FIG. 8 below). Additionally, one or more inductive power transfer terminals 716 are positioned on the outer portion of the housing to facilitate inductive power transfer between the MCD and the probe 300 . Inductive power transfer is chosen in the present embodiment so as to obviate the need for a chemical battery or other potentially hazardous power source within the probe 300 , although a battery may be used. Alternatively, in another embodiment, a radio frequency (RF) oscillator and supporting circuitry (not shown) is disposed within the housing 302 on the PCBA 510 to receive radio frequency energy generated externally to the patient and convert this energy to direct current power within the probe 300 .

[0050] So as to fit within the limited volume of the cavity 303 , each of the aforementioned components 504 , 510 , 512 , 514 , 516 , 518 , 520 , 524 , 526 is chosen to have the minimum physical profile. While several discrete component functions are depicted in the functional block diagram of the probe data acquisition and transfer circuitry 600 (described below with reference to FIG. 6 ), in actuality many of these functions can be integrated and performed by a lesser number of devices so as to economize on space. For example, a Texas Instruments MSP430×MSP ultra low power microcontroller (such as in the “DW package”) incorporating internal memory, clock, and ADC may be used in the resent embodiment. Application specific integrated circuits (ASICs), FPGAs, or other custom ICs having a high degree of integration may also be used for such purposes. Such integration is desirable in the present invention, and is presently well within the capability of those skilled in the semiconductor design and fabrication arts. Alternatively, a larger number of discrete components (as shown in FIG. 5 ) may be used. For example, a Texas Instruments TLV2543C flash ADC with a 20 pin “DB” package (roughly 8 mm×7.5 mm×2 mm) may be used as the ADC 512 of the present embodiment. This package more than adequately fits within the aforementioned 12 mm outer housing 302 (assuming a 0.5 mm housing wall width), while preserving space for the other components. Preferably, a BGA (ball grid array) package is utilized to eliminate leads along the edge of the package(s) and further economize on space. It will be appreciated, however, that a wide variety of integration schemes, packages, profiles, and lead (pin) structures may be used in the present invention in order to simultaneously fit all of the desired components within the aforementioned outer housing 302 .

[0051] The circuit board assemblies 510 of the present embodiment are preferably multilayer boards having a plurality of circuit traces, vias, and contact pads disposed therein to facilitate electrical interconnection of the various terminals of the integrated circuits (ICs) and any discrete electrical components (such as the LED 504 , resistors, capacitors, or transistors). The design and fabrication of such circuit boards is well known in the electrical arts. Electrical interconnection between the multiple PCBAs 510 of FIG. 5 is accomplished via miniature flexible electrical tracing (not shown). Note that in the present embodiment, the PCBAs 510 are disposed in a generally longitudinal fashion (i.e., parallel to the longitudinal axis of the probe housing 302 ); however, other orientations, such as transverse to the longitudinal axis, could be used.

[0052] The LED 504 used in the embodiment of FIGS. 3 - 5 is a standard, low voltage lightemitting diode having a spectral emission characteristic centered in the visible wavelengths. In the present embodiment, a “white light” LED of the type well known in the electrical arts is preferred, although other types, power ratings, and spectral outputs are possible. This LED 504 is used as an optical illumination source for the CCD array 402 previously described. Specifically, light generated by the LED is passed via its fiber optic bundle 508 to the optical lens 306 c and radiated out of the probe 300 into the region immediately surrounding the CCD array 402 . The fiber optic bundle is, in this embodiment, a single mode optical fiber of the type well known in the optical transmission arts. Light reflected by the interior surfaces of the patient's intestine is gathered by the main lens 306 a and focused on the CCD array 402 , including the visual sub-array 402 b, where it generates charge within the individual CCD array cells. The voltage and power rating of the LED 504 is chosen to be compatible with the desired light intensity, power supply circuit capacity, and system voltage available within the probe. In the present embodiment, a milliwatt LED is used having a voltage rating on the order of 25 Vdc, although other may be used.

[0053] Referring now to FIG. 6 , one embodiment of the data acquisition, processing, and transfer circuit 600 of the smart probe of FIGS. 3 - 5 is disclosed. As previously described, the circuit 600 of the present embodiment comprises a number of components including, inter alia, a CCD array 402 , parallel and serial drivers 516 , 518 , sample and hold circuit (SHC) 514 , system clock 524 , microcontroller 520 , amplifier 522 , ADC 512 , and data transfer sub-circuit 526 . Other electronic elements (such as capacitors, resistors, transistors, and diodes; not shown) are also used to facilitate operation of the circuit 600 ; the use of such components is well known in the relevant arts and accordingly will not be discussed further herein. Furthermore, it will be noted that such electronic elements are ideally integrated with one or more of the aforementioned components 512 , 514 , 516 , 518 , 520 , 522 , 524 , 526 in order to minimize space consumed within the probe outer housing 302 .

[0054] As shown in FIG. 6 , the CCD array is driven by the parallel and serial drivers 516 , 518 based on a user-defined clock signal output from the clock/timer 524 and controlled by the microcontroller 520 . Analog signals output from the CCD array are amplified by amplifier 522 and passed to SHC 514 . Analog signals output from the SHC 514 are rapidly converted by the ADC 512 into digital signals, the latter being input to the data transfer sub-circuit 526 . A “flash” ADC (i.e., one with a sampling rate on the order of microseconds or less) is used to permit streaming of video data at video rates, typically 720 MHz. A 10 or 12-bit resolution ADC may be used, for example, to accommodate the dynamic range of the CCD. The required ADC resolution can generally be determined by the following relationship:

N≧(DR/6.02)

[0055] Where:

[0056] N Number of data bits

[0057] DR Dynamic Range of CCD in db

[0058] The data transfer sub-circuit 526 comprises a modulator 528 , demodulator/filter 529 , transistor stage 530 , and data transfer terminal 532 . The construction and operation of inductive terminals is well known in the electronic arts, and is described in, inter alia, U.S. Pat. No. 4,692,604 “Flexible Inductor” issued Sep. 8, 1987, which is incorporated herein by reference in its entirety. Note that in the present embodiment, the “flexible” inductor of the '604 patent is configured so as to form a circumferential ring within the probe outer housing, as shown in FIG. 3 . A high frequency (MHz) clock signal is supplied by the clock 524 to the modulator 528 so as to generate an ac carrier. The data signal output from the ADC 512 is used by the modulator 528 to modulate the aforementioned ac carrier, thereby producing an amplitude modulated ac waveform on the coil of the data terminal 532 by way of the transistor stage 530 . The output of the probe data terminal 532 is a magnetic flux which varies according to the amplitude modulated ac signal carried on the terminal coil. The coil 542 of the MCD remote unit data terminal 540 is inductively coupled to the probe data terminal coil via the magnetic flux; accordingly, an amplitude modulated, alternating current signal of the same phase and frequency is generated in the remote unit coil 542 . This signal is then demodulated using, for example, a diode and filter capacitor as described in U.S Pat. No. 4,605,844, “Computerized Transaction Card With Inductive Data Transfer”, issued Aug. 12, 1986, which is also incorporated by reference herein in its entirety. The resulting demodulated data signal, a replica of the data signal supplied by the output of the ADC 512 , is input to the front-end processing (e.g., DAC or DSP) of the MCD, as described with reference to FIGS. 8 and 9 below. It will be further recognized that the design of the data transfer sub-circuit 526 must consider the video data rates previously described (typically 7-20 MHz).

[0059] The demodulator/filter 529 performs two functions: (i) demodulating the control and data signals sent by the MCD microprocessor during probe startup and operation; and (ii) isolation and filtering of any errant power transfer signal which couples to the inductive coil(s) of the data transfer terminal 532 .

[0060] Referring now to FIG. 7 , one embodiment of the inductive power transfer circuit 700 used in the smart probe of FIGS. 3 - 6 and MCD remote unit 802 is described. Similar to the inductive data transfer sub-circuit 526 illustrated in FIG. 6 , the power transfer circuit 700 utilizes a clocking signal generated by the clock 702 in the MCD remote unit 802 to supply a parallel transistor stage 703 including two pairs of transistors 704 a, 704 b and associated MOSFETs 706 a, 706 b . One pair of transistors 704 a is supplied via an signal inverter 708 so as to invert the phase (i.e., shift by 180 degrees) of the signal with respect to the non-inverted signal supplied to transistors 704 b. An alternating current waveform (of a different frequency than that imposed upon the data transfer terminal(s) 532 ) is accordingly generated within the coil 710 of power transfer terminal 712 , which is inductively coupled to the coil 714 of the power transfer terminal(s) 716 in the probe 300 . A diode (rectifier) stage 720 including filter capacitor (not shown) is used to convert the induced ac signal in the probe coil 714 to direct current. A voltage regulator and conversion circuit 722 is used to regulate and adjust the voltage of the converted dc power prior to supply to the other components 402 , 504 , 512 , 514 , 516 , 518 , 520 , 522 , 524 , and 526 within the probe 300 via the various voltage busses 730 , 732 , 734 . The construction and operation of voltage regulating and conversion circuits is well known in the electrical arts, and will not be discussed further herein. U.S Pat. No. 4,692,604, previously cited herein, describes the construction and operation of inductive power transfer circuits such as that utilized herein in greater detail.

[0061] Similarly, it will be noted that the method of clocking signal recovery described in the above-referenced patent may be utilized in the present invention to obviate the clock 524 of FIG. 6 . Specifically, the ac waveform transferred from the MCD remote unit 802 can be used to generate a clock signal prior to rectification by the diode stage 720 using a clock recovery circuit 740 . This clock signal may then be used to drive those components requiring a clock signal, such as the CCD array 402 , ADC 512 , etc.

[0062] It will be further recognized that while the present embodiment utilizes inductive data and power transfer, other methods of such transfer are possible. See, for example, the capacitive data transfer apparatus described in U.S. Pat. No. 4,816,654, “Improved Security System for a Portable Data Carrier”, issued Mar. 28, 1989, which is incorporated herein by reference in its entirety.

[0063] Referring now to FIG. 8 , the monitoring and control device (MCD) 800 of the present invention includes, in a first embodiment, a remote unit 802 which can be placed in close proximity to the patient's abdomen in the region of the intestine where the probe 300 is located to permit inductive data and power coupling thereto. The remote unit 802 includes, inter alia, one or more inductive data terminals 540 , and one or more inductive power transfer terminals 712 These terminals 540 , 712 are located within the unit so as to provide adequate separation during operation, yet still permit simultaneous contact with the probe 300 while in the patient. The operation of these terminals is described in greater detail above with respect to FIGS. 6 and 7 . As shown in FIG. 8, a circular “ring” configuration is used for the terminals 540 , 712 in the present embodiment so as to minimize the effects of different azimuthal orientations of the remote unit 802 with respect to the probe 300 , although it will be appreciated that other configurations (such as pins, rods, strips, etc. may conceivably be used). As the probe 300 slowly moves within the intestine, the remote unit 802 is moved accordingly by the operator so as to maintain contact therewith. Since the inductive coupling between the data and power transfer terminals 540 , 712 of the remote unit and terminals 532 , 716 of the probe is substantially affected by the distance between the respective terminals, as well as the interposed material (tissue, fluids, etc.), the remote unit 802 must be periodically moved while the probe 300 is in use.

[0064] The remote unit is connected to the MCD main unit 804 via a standard data transmission cable 806 of the type well known in the electrical arts. As further illustrated in FIG. 9 , the MCD main unit 804 of the present embodiment includes, inter alia, a “flash” digital to analog converter (DAC) 902 , digital signal processor (DSP) 904 , microprocessor 906 , encoder 908 , video display driver 910 , display unit 912 , video memory 914 , and nonvolatile storage device 916 . Image data transmitted from the probe 300 is passed to the main unit 804 from the remote unit 802 , de-compressed if required by the DSP 904 , converted to an analog format by the DAC 902 , coded by the video encoder 908 , and displayed on the display unit 912 . These displayed visual or autofluorescence images constitute one form of diagnostic aid according to the present invention, although it will be recognized that other such aids (such as ultrasound images) may be produced. Images may be stored in the storage device 916 for a variety of functions (such as later retrieval or enhancement) if desired, as is well known in the electronic arts. The microprocessor 906 acts to control the operation of the MCD 804 as well as the probe 300 via data signals transmitted to the probe during startup and operation. Specifically, the microprocessor 906 of the MCD generates and passes control data to the microcontroller 520 of the probe via a modulator circuit 911 and the inductive data terminals 532 , 540 on startup to initiate microcontroller control of the probe. The probe microcontroller 520 , which is connected to and receives input from the clock 524 (or alternatively, the clock recovery circuit 740 associated with the power transfer circuitry), switches power to the remaining (non-powered) probe components such as the SHC 514 and ADC 512 and generates the necessary signals to the various probe components (based on its internal programming) so as to initiate operation of the LED 504 , collection of image data via the CCD array 402 , and subsequent processing/transfer of the collected data.

[0065] The remote unit 802 of the MCD 800 is, in a second embodiment, a band which is fitted around the abdomen of the patient (not shown). This band includes a plurality of individual data and power transfer terminals each of which are capable of transferring data and power inductively between the MCD and the probe 300 . The terminals are physically arranged in an interleaved fashion (alternating data and power transfer terminals) so as to provide a high density of terminals yet minimize any interference between terminals. The data terminals are electrically arranged so as to allow the MCD to select and display data received from one or more of the data terminals (channels). This multi-terminal approach is used to allow the probe to maintain contact with the MCD remote unit with minimal or no movement of the remote unit. As the coupling between one set of data terminals is increased with respect to the other terminals, the signal quality for that channel increases accordingly. In one embodiment, the digital data received from the data terminals is input to a high frequency multiplexer. The multiplexer generates a single multiplexed output (based on the multiple data channel inputs) which is input to a DSP. The DSP samples and analyzes the data on the single multiplexed channel for each input channel using an internal algorithm to evaluate the strength and quality of signal on that input channel. The microprocessor selects the most viable channels at any given time based on the output of the signal sampling algorithm running on the DSP, and utilizes the selected input channel as the data source for the DAC and video driver.

[0066] Conversely, all of the multiple power transfer terminals in the remote unit of the second embodiment are driven synchronously and simultaneously by the MCD so as to permit inductive coupling with the probe at all times, thereby minimizing power “drop outs”.

[0067] FIG. 10 a is a perspective view of a second embodiment of the smart probe of the present invention. The probe 1000 of FIG. 10 a comprises an outer housing 1002 having a generally cylindrical shape with rounded ends (“capsule”), an inner cavity 1003 (not shown), and a lens aperture 1004 positioned in one end of the housing 1002 . Three lenses 1006 a, 1006 b, 1006 c are mounted in alignment with the aperture 1004 , and optionally protected by a lens cover. The third lens 1006 c of the present embodiment is used to distribute laser (coherent) light energy generated by a laser diode which is described in greater detail below. The CCD array 1010 includes two sub-arrays 1010 a, 1010 b ( FIG. 10 b ) for the collection of visible ambient and light emitted by autofluorescence, respectively. The probe 1000 further includes a digital signal processor (DSP) and memory (not shown) which facilitate processing and storage of the data collected by the CCD sensor and control of the probe, as described below. Data transfer terminals 1040 and power transfer terminals 1043 are embedded at or near the surface of the housing 1002 , as in previous embodiments.

[0068] Referring now to FIG. 10 b, a front view of the smart probe 1000 of FIG. 10 a is shown, illustrating the relationship of the housing aperture 1004 , lenses 1006 , the CCD array 1010 , and the lens cover 1008 . Specifically, the aperture 1004 is sized and shaped to accommodate the CCD array 1010 and associated main lens 1006 a, laser energy lens 1006 b, and the optical light lens 1006 c. The laser and optical lenses 1006 b, 1006 c are positioned laterally to the main lens 1006 a in this embodiment. The aforementioned optional lens cover 1008 conforms to the outer surface of each of the lenses 1006 a, 1006 b , 1006 c. Both remitted visible light and emissions resulting from the autofluorescence of the surrounding tissue are passed through the main lens 1006 a (which is chosen to be effectively transparent to a broad range of wavelengths in the spectral regions of interest) to the CCD array 1010 . The main lens 1006 a is, in the embodiment of FIGS. 10 a and 10 b, a substantially convex lens designed to gather and more narrowly focus energy originating from various positions outside the probe 1000 onto the CCD array 1010 . The laser lens 1006 b and optical lens 1006 c are, conversely, designed to radiate and distribute light incident on their inner surfaces (via their associated fiber optic bundles) more broadly within the intestine.

[0069] The CCD array 1010 of the present utilizes an interleaved design whereby individual charge collecting cells having sensitivity to broad spectrum visible light are spatially mixed with cells having sensitivity within a range of wavelengths ideally centered on the autofluorescence peak associated with biological tissue within the interior of the patient's intestine ( 530 mn in the present embodiment). Hence, two separate CCD sub-arrays are formed (each having approximately half of the total number of cells in the array 1010 ); (i) a “visible” light sub-array 1010 a, and (ii) an “autofluorescence” sub-array 1010 b. As shown in FIG. 10 b, the pixels of the two sub-arrays 1010 a, 1010 b are physically interleaved such that alternation between the pixels of each sub-array occurs in the row dimension only. Therefore, when reading voltage data out of the array 1010 on a row-by-row basis, data from successive cells will be associated with alternating sub-arrays. When data is serially read out of the array 1010 of FIG. 10 b in the column direction, an entire column is associated with the same sub-array. This arrangement is used to permit the data acquisition circuitry (described further below with respect to FIG. 12 ) to readily parse data from the two sub-arrays 1010 a, 1010 b and store it at different locations within the device memory 1026 . It will be recognized that other types of interleaving of the array 1010 may be used in conjunction with the present invention, however. For example, alternation of pixels on a column basis may be used. Alternatively, pixels could be alternated on both a row and column basis. Furthermore, interleaving of the pixels need not be used; rather, a single multifunction CCD array, or a system of two or more discrete CCD arrays arranged in some other spatial relationship (such as side-by-side, or over-under) could be used, either with a single lens 1006 a as shown in FIG. 10 b, or separate, dedicated lenses.

[0070] Referring now to FIG. 11, a cross-section of the probe 1000 of FIGS. 10 a and 10 b is illustrated. The probe outer housing 1002 generally contains a number of different components in its internal cavity 1003 including the aforementioned lenses 1006 a, 1006 b , 1006 c and CCD array 1010 , as well as a semiconductor laser 1012 , light emitting diode (LED) 1014 , two respective single mode fiber optic bundles 1016 , 1018 , and one or more data transfer terminals 1020 . A number of discrete or integrated semiconductor components are also present within the probe 1000 , including, inter alia, an analog-to-digital converter (ADC) 1022 , a digital processor 1024 , microcontroller 1025 , digital memory 1026 with integral memory controller, as described in greater detail below. The semiconductor laser 1012 and LED 1014 are located approximately co-linearly with the central axis of their respective lenses 1006 b, 1006 c, with the fiber optic bundles 1016 , 1018 disposed there between as shown in FIG. 11 . The laser and LED 1012 , 1014 , their respective bundles 1016 , 1018 , and respective lenses 1006 b, 1006 c are optically coupled so as to transmit light energy to the lenses in an efficient manner. The ADC 1022 , signal processor 1024 , memory 1026 , and other electronic components are disposed within the cavity 1003 on one or more miniature printed circuit board assemblies (PCBAs) 1030 in a space-efficient manner, with the semiconductor components being disposed and electrically connected on either side of the assemblies 1030 . One or more data transfer terminals 1040 in the form of circumferential rings are located within the outer housing at or near the surface thereof in order to provide for data transfer between the probe 1000 and the MCD remote unit (not shown). Additionally, a power transfer circuit 1042 with transfer terminals 1043 similar to that described with respect to the embodiment of FIGS. 3 - 7 is disposed within the housing 1002 on a PCBA 1030 to receive and demodulate inductive modulated energy generated externally to the patient by the MCD remote unit. Optionally, in yet another embodiment, a NiMH or comparable miniature battery (not shown) and supporting circuitry may be included within the outer housing 1002 as a power source in lieu of the aforementioned inductive power circuit 1042 .

[0071] As previously discussed with respect to the embodiment of FIGS. 3 - 7 , the package profiles of the components used within the present embodiment are chosen so as to permit all of the above-described components to be fit within the outer housing. This becomes particularly critical with respect to the embodiment of FIGS. 10 a, 10 b, and 11 , since there are substantially more components contained within the outer housing 802 . The size of each component package must be weighed against the necessity of the component and the overall available space within the probe housing 1002 . For example, when choosing a DSP package, the necessary MIPS, degree of integration of other functions within the DSP (such as, DMA, internal memory, etc.) are balanced with the available space within the housing. Similarly, the memory storage capacity is balanced with the physical package size in order to optimize all parameters. Also, as previously discussed, the use of highly integrated multifunction devices is desirable in order to reduce the size of the probe 1000 . For example, embedded memory (i.e., that integrated within the DSP or other component package) may be employed as the capability of such devices increases. Furthermore, the placement of the individual components at various locations on the PCBAs 1030 (as well as the placement of the PCBAs themselves) is optimized for space.

[0072] In light of the foregoing, it will be appreciated that the size and shape of the probe outer housing 1002 can be adjusted to accommodate internal components of varying sizes, consistent with the requirement that the housing be sized and shaped to permit passage through the desired portion of the patient's intestinal tract. Typically, the ileocecal valve at the juncture of the small and large intestines will constrain the maximum diameter of the probe housing. The probe housing 1002 of the embodiment of FIGS. 10 - 11 is larger (roughly 40 mm in length, and 15 mm in diameter) than that of the embodiment of FIGS. 35 (roughly 30 mm in length, and 12 mm in diameter), although it will be recognized that other sizes and shapes may be used.

[0073] The laser 1012 of the smart probe 1000 is now described. A semiconductor (diode) laser is used in the embodiment of FIGS. 10 - 11 to generate laser energy in the desired wavelength band. In the present embodiment, a center wavelength of 530 nm (corresponding to green light) is used, although it will be recognized that other wavelengths may be chosen based on the response of certain types of tissue and the needs of a specific application. As shown in FIG. 2 , the ratio of measured fluorescent intensity for diseased tissue to that of normal tissue is minimized (and both the absolute intensity and intensity difference maximized) at roughly 530 nm, thereby effectively increasing the resolution and signal-to-noise ratio of the system without additional processing. A micro-package diode laser is utilized based on availability and cost, output power, size, and power consumption considerations, although other lasers may be used. A laser driver circuit 1013 (such as a model NS102 manufactured by NVG Corporation) is used in conjunction with the aforementioned laser diode in order to control the operation and output of the diode. Note that the size of the laser diode and driver circuit (on the order of a few millimeters in all dimensions) allows conservation of space within the probe outer housing 1002 . The laser 1012 may be configured to operate in either pulsed or CW (continuous wave) modes, or both, depending on the needs of the operator. Switching between modes of operation is accomplished via the microcontroller 1025 , as is well known in the art.

[0074] Referring now to FIG. 12 , one embodiment of the data acquisition, storage, and transfer circuit 1200 of the present invention is described. As shown in FIG. 12 , the circuit 1200 comprises generally a combined CCD array 1010 , analog-to-digital converter (ADC) 1022 , digital signal processor (DSP) 1029 , microcontroller 1025 , random access memory (RAM) with integral memory controller 1026 , and a data transfer sub-circuit 1027 . Other components include a system clock/timer 1044 , parallel/serial drivers 1046 , 1048 , sample and hold circuit 1050 , data compression algorithm (running on the DSP), and data transfer terminal(s) 1040 . The function and operation of these components are described in greater detail below.

[0075] As previously described, the CCD array 1010 is used to gather light energy of varying wavelengths, and produces a voltage output which is proportional to the intensity of the incident light. Note that during laser operation, the cells of the CCD may be drained if required to prevent damage. The analog output of the CCD array is fed to the ADC 1022 , which converts the analog signal to a digital representation. The ADC of the present embodiment has at least two analog input channels which are multiplexed to permit the conversion of analog voltage data generated by either of the CCD sub-arrays 1010 a , 1010 b to a digital format. The digital output of the ADC is fed to the DSP 1024 which performs a variety of control and signal processing functions including demultiplexing of the multiplexed ADC signals, and signal compression for storage in the memory 1026 . The DSP takes the digital data received from the ADC, demultiplexes and formats it, and optionally compresses it for storage within the memory using any number of data compression techniques such as pulse code modulation (PCM) or delta pulse code modulation (DPCM), which are well known in the signal processing arts. Data compression is performed within the DSP using an algorithm adapted for such purpose which is stored within the program or flash memory of the DSP 1024 or, alternatively, within the off-chip memory 1026 . It will be appreciated that while a DSP having a program memory is used in the present application, other types of processors may be substituted based on the chosen data acquisition and transfer properties. A discretely packaged DSP such as a Texas Instruments TMS320C2xx series processor (roughly 14 mm×14 mm×2 mm in the “PN” PQFP package) could feasibly be used in the present embodiment, although as previously discussed, it is desirable to integrate as many probe functions into one IC as possible in order to economize on space within the probe outer housing. Note that if data compression is not used, the need for a DSP is obviated, since other functions may be performed by the microcontroller 1025 . The DSP 1024 interfaces with the memory controller within the memory 1026 which controls the accessing and storage of data therein. The probe memory 1026 of the present embodiment is a standard 3.3. V logic static random access memory (SRAM), although other types of memory (such as DRAM, SDRAM, “flash”, or SLDRAM) may be used. 3.3. V SRAM is preferred based on its comparatively low power consumption and static data storage properties. The memory 1026 is chosen to have adequate storage capacity for compressed (or non-compressed) data output from the DSP 1024 during imaging. The memory 1026 , depending on the operating mode of the probe (e.g., streaming data externally via the data transfer sub-circuit, or storing internally), must be able to store a sufficient amount of data so as to permit (i) any buffering of the data necessitated by the data transfer sub-circuit 1026 , and (ii) storage of at least one frame (and preferably more) obtained by the CCD array 1010 . In the present embodiment, a sub-array of 31,680 pixels is used (192 pixels per line, 165 lines per sub-array); hence, a memory storage capacity corresponding to binary representations of at least this number of pixels is used. The memory storage capacity needed is further determined by the type and efficiency of compression utilized, if any. Compression is used not only to minimize the size and increase the capacity of the memory 1026 within the probe, but also to minimize the bandwidth necessary to transmit data via the data interface sub-circuit 1027 .

[0076] It will be recognized that while the foregoing descriptions of the smart probe of the present invention are cast in terms of embodiments having laser and/or broad spectrum visual light sources, a CCD array, inductive power and data transfer, and signal processing and/or data storage capability, any number of different combinations of these features (or even other features) may be used consistent with the present invention. For example, a probe having a laser diode, CCD array, capacitive data transfer, and battery power supply is contemplated. Alternatively, other embodiments of the smart probe could include a device for obtaining a microsample (biopsy) of intestinal tissue, or for delivering a dose of a drug, chemical, or even ionizing radiation to, inter alia, otherwise inaccessible portions of the intestine of the patient. A large number of alternate configurations are possible, all being within the scope of the present invention.

Endoscopic Delivery Device

[0077] Referring now to FIG. 13 a, a first embodiment of the endoscopic delivery device of the present invention is disclosed. Specifically, the device 1300 of FIG. 13 a includes a housing 1302 located at its distal end 1304 , the housing having an internal cavity 1306 sized to receive the smart probe 300 of FIG. 3 (or alternatively, other embodiments). The housing 1302 and distal end of the device 1304 are sized so as to permit passage through the esophagus and stomach of a patient. The cavity 1306 is open at the distal end of the device, such that the smart probe 300 may be inserted into the cavity via an aperture 1308 .

[0078] A closure or diaphragm 1310 is mounted over the aperture 1308 as shown in FIG. 13 a. The closure 1310 is, in the present embodiment, a substantially hemispherical membrane which is scored or perforated in one or more areas of its surface so as to be substantially weakened in these areas (see FIG. 13 b ). In one embodiment, the closure is scored radially as shown in FIG. 13 . One or more tubes 1316 running down the length of the delivery device 1300 terminate in the cavity 1306 in the region 1312 behind the probe 300 (when inserted in the housing 1302 ). A pliable, ring-shaped seal 1314 is fitted to the interior of the housing near the aperture 1308 , the seal having an inner diameter of its sealing surface approximating that of the probe outer housing 302 . The seal 1314 is sized so as to permit easy movement of the probe 300 through the seal, yet also maintain adequate sealing against the gross leakage of fluid (or gas) past the seal. A non-toxic fluid or gas (such as water, or air) is applied via the tube(s) 1316 during implantation of the smart probe in order to expel the probe from the housing 1302 and cavity 1306 . Collectively, this arrangement comprises the release mechanism.

[0079] As the portion of the cavity 1306 behind the probe and seal 1314 is pressurized by the fluid/gas, the probe 300 is displaced forward within the cavity so as to contact the closure 1310 . The scores 1320 in the closure 1310 will eventually yield under the force exerted by the probe, thereby rupturing the closure and allowing the expulsion of the probe from the cavity. It will be recognized that the yield stress of the closure scores 1320 is preferably set such that an extremely low fluid/gas pressure is required to rupture the closure, thereby causing the probe 300 to move slowly out of the housing 1302 and preventing any potential trauma to the interior region of the patient's intestine from the expulsion transient. Additionally, the rate of pressure increase within the cavity 1306 can readily be controlled by the operator using any number of available means such as a hand pump, low volumetric flow rate mechanical pump, or the like.

[0080] While the present embodiment describes a mechanically ruptured closure and associated fluid system for expelling the probe, it can be appreciated that a number of different ways of rupturing or dissolving the closure may be employed. For example, minute electrical filaments could be used to melt portions of the closure prior to probe expulsion. Alternatively, the closure could be dissolved or weakened by the presence of one or more chemical agents, or even light energy. It will be further recognized that the closure is optional and may not even be used in certain applications, especially if a lens cover 308 is used on the probe 300 .

[0081] In the embodiment of FIG. 13 a , a narrow fiber optic bundle 1322 and lens 1323 is routed around the periphery of the probe and within the housing 1302 of the endoscopic delivery device 1300 in order to assist the operator in locating and implanting the smart probe 300 . Light gathered by the bundle 1322 and lens 1323 is transmitted to a video display unit or other means of viewing (not shown). It will be recognized, however, that other means of viewing the probe 300 during delivery (both direct and indirect) may be used. For example, the probe/delivery device location could be viewed using ultrasonic, magnetic resonance, or X-ray imaging.

[0082] A second embodiment of the improved endoscopic delivery device according to the present invention is shown in FIG. 14 . In this embodiment 1401 , the smart probe is biased by a spring or other means (such as an elastic member) toward the aperture 1408 in the housing such that the probe is urge from the cavity 1406 and housing 1402 , as shown in FIG. 13 b. A retaining detent or latch 1440 is positioned at or near the aperture 1408 and engages a recess 1442 in the outer housing 302 of the probe 300 such that when the probe is inserted into the cavity and latched, the spring 1446 (or other biasing means) biases the probe 300 against the latch 1440 . The latch is, in the present embodiment, actuated by a miniature cord or cable 1450 disposed within a channel 1452 running longitudinally up the side of the delivery device 1401 , although it will be recognized that a myriad of different release mechanisms may be used. Alternatively, an outer closure (not shown) may be used in place of the latch 1440 to retain the probe 300 within the housing against the biasing force until the closure is sufficiently weakened by electrical energy, light energy, or the presence of a chemical agent.

Method of Providing Diagnosis and Treatment

[0083] Referring now to FIG. 15, a method of providing diagnosis and treatment of a patient using the apparatus of the present invention is disclosed.

[0084] It will be recognized that while the following method recites a series of steps in a given order, this order may be permuted where appropriate such that the steps recited herein may be performed in alternate sequences. Additionally, certain steps (including, for example, the installation of the lens cover) may be completely omitted, or other steps added. The following description is meant only to be illustrative of the method of the present invention.

[0085] It will be further recognized that while not recited as a specific step in the embodiment of the method described below, patient intestinal preparation prior to introduction of the smart probe is essential to the proper operation of the probe while in the patient. Such intestinal preparations exist in a myriad of different varieties and are well understood by those of ordinary skill in the medical airs, and accordingly shall not be discussed further herein.

[0086] Additionally, while the following description of the method of the present invention is cast in terms of delivery via an endoscopic delivery device, it will be appreciated that other methods or forms of delivery device may be used, and that the method is not limited to one form of delivery. For example, the probe may be sized such that it can be swallowed by the patient. Ultimately, as the probe is passed through the stomach into the small intestine after swallowing, it will be oriented based on its shape (substantially ellipsoid or cylindrical in the preferred embodiments) so as to facilitate data gathering.

[0087] In the first step 1502 of the instant method 1500 , the type/configuration of probe to be used is determined based on the parameters of the patient and the information desired, and a testing protocol selected. For example, if only a visual inspection of a portion of the intestinal wall of a patient is desired, then a probe of the type described with reference to FIGS. 3 - 7 above is selected. Such a probe can arguably have a smaller profile (due to its simpler construction as compared to the probe of FIGS. 10 - 11 ), and therefore may be better suited in applications where intestinal strictures may exist.

[0088] The probe is then tested outside of the patient to verify proper operation in step 1504 . Such testing may include, inter alia, testing of the operability of the CCD array, laser diode and DSP (if so equipped), LED, data transfer circuit, and inductive power circuit. It will be recognized that a number of different test protocols may be used depending on, inter alia, the specific configuration of the probe.

[0089] Next, the proper lens cover is chosen for use with the probe and installed if desired in step 1506