WO2001043057A1

WO2001043057A1 - Method and apparatus for analyzing medical images

Info

Publication number: WO2001043057A1
Application number: PCT/US2000/042722
Authority: WO
Inventors: Kenneth C. Weil; Jeffrey Levy; Michael Henry
Original assignee: Med Detect Inc.
Priority date: 1999-12-10
Filing date: 2000-12-08
Publication date: 2001-06-14
Also published as: AU4311701A

Abstract

An apparatus and method for facilitating the review of medical images. The system and method utilize a viewer (72) which can display a first image (82) and a decoder (74) which reads a patient code associated with the first image to initiate automated retrieval of supplemental information related to the first image. In preferred embodiments, the patient code is a bar code (86), the decoder is a bar code reader and the supplemental information includes a second image derived from the first image which highlights features or regions of potential medical significance. The methods and apparatus have particular utility in mammography screening.

Description

METHOD AND APPARATUS FOR ANALYZING MEDICAL IMAGES

FIELD OF INVENTION The present invention relates to the field of retrieving, processing and analyzing medical data, especially medical images and patient information pertinent to such medical images. For example, in certain embodiments, the present invention is related to streamlining the processing and analysis of conventional x-ray mammograms by medical personnel in conjunction with a digital image derived from the x-ray mammogram, the digital image having been processed by a processor which compares the digital image with preselected criteria to provide an indication of regions of potential medical significance.

BACKGROUND OF THE INVENTION One of the major advances in medicine has been the development of sophisticated imaging techniques for the detection and monitoring of disease. Such techniques have enabled physicians to identify and treat diseases at earlier stages and to better judge the effectiveness of treatment, with the net result being better prognoses for patients.

The new imaging techniques can be utilized to obtain images of various subject matter. For instance, images of various body parts are now routinely obtained using different radiology and magnetic imaging technologies. Rather than obtaining images of a complete body part or section of the body, an image may be obtained of a specimen taken from a patient, such as a sample from an organ, tissue or biological fluid. These types of images are more common in the field of pathology for example. The increasingly high-tech nature of medical image analysis is further reflected by the fact that many times an image may be taken at one location but an analysis, or at least a partial analysis, may be performed at a second remote location, the initial image being transmitted to the remote site by electronic means. Increasingly, the initial analysis of medical images is being conducted using computer algorithms to identify features which are characteristic of certain diseases. It is also frequently becoming the case that images are being stored in various types of electronic storage devices so that images can be reviewed at different time periods; this makes it possible to accurately monitor the progress of treatment for example.

With the advent of new medical imaging technologies, the increasing occurrence of transmitting images to analysis centers and then back to treatment centers, and archival storage of medical images, there has developed an increased need for simple yet rapid means for identifying, tracking and accessing medical images. For instance, there must be a convenient way for identifying and retrieving images and relevant patient information regarding the images. Mammography serves as an illustrative example of the problems associated with current methods for locating and handling medical images. Current mammogram procedures typically begin by obtaining an x-ray image of the breast being examined, although machines capable of obtaining digital images of the breast are becoming increasingly available. A label containing the patient's name or identification number may simply be stuck to the x-ray using an adhesive backing on the label. Alternatively, the label may be "flashed" onto the x-ray film using a specially designed light box which exposes the label onto the x-ray film.

The x-ray image may be used in a computerized process to generate a second or processed image in which features of potential medical significance are highlighted. A medical professional such as a radiologist examines both the original x-ray image and the processed image to make a medical determination as to whether there is in fact evidence of some type of abnormality. In the case of mammography, such abnormalities are most frequently a suspicious mass or a calcification. In examining the two images, the x-ray image is usually displayed on a "viewer" or "alternator." To access the processed image, the radiologist typically must manually type in or input certain patient information to access the processed image from electronic storage. Once accessed, the processed image is displayed on a second viewer or screen.

The analysis for analyzing mammograms just described illustrates two of the major problems currently associated with medical image analysis. Current methods are inefficient and limit the volume of images that can be processed because the analyst must manually input information to obtain the processed image.

Consequently, there is a need for new automated methods and apparatus for obtaining and analyzing medical images which streamline and facilitate the review of such images by medical professionals. This is particularly true in cases in which an initial image is used to generate a second image or other processed information which the analyst or medical professional then uses in conjunction with the original image in conducting a medical evaluation. There is also a need for methods and apparatus for analyzing medical images which 1) require minimal or no input by medical professional in order to access the second image or other supplemental information related to the original image, thereby allowing the medical professional to concentrate on the analysis, 2) allows for faster and more efficient evaluation, 3) are compatible with long term storage and retrieval, 4) allows for tracking of images when they are processed at a remote location, 5) assists in tracking when numerous images are processed simultaneously, 6) ensures that patients' results are linked correctly to patient films, 7) preserves patient confidentiality when transmitting images to a remote location, and 9) facilitates rapid retrieval of older (or any other) films for a given patient. An embodiment of the present invention does not necessarily need to address each of these objectives.

SUMMARY OF INVENTION

The present invention provides methods and apparatus for acquiring, processing and retrieving medical information which satisfy the needs identified above. The methods and apparatus provided for in the current invention allow medical professionals to obtain a medical image and then link a patient code with the original image. The patient code can be utilized to automate the retrieval of supplemental information which the physician can use in tandem with the original image to diagnose or monitor disease.

The methods and apparatus satisfy the criteria set forth above. Because the methods and apparatus utilize a patient code, client confidentiality may be maintained when transmitting images to remote locations. The methods and apparatus also allow for automated access to the supplemental information associated with the original image, thus freeing the medical professional to concentrate on analysis and making for a faster and more efficient process. Finally, the methods and apparatus are compatible with, and provide for, short term and long term storage of the original image and supplemental information. More particularly, the present invention provides a system for facilitating the analysis of medical images which generally comprises a first viewer and a decoder. The first viewer displays a first image so that it can be viewed by a medical analyst. The first image includes a representation of a patient's body part or a representation of a specimen taken from the patient, in addition to a patient code which encodes desired information about the patient. The decoder reads or decodes the patient code and, in so doing, initiates automated retrieval of supplemental information also associated with the same patient code from a data storage unit. The medical analyst can use the first image in conjunction with the supplemental information to perform a medical evaluation, such as diagnosing or monitoring the treatment of a disease. The system may also include one or more of the following devices in addition to the first viewer and decoder. For instance, the system may include an image collector which is utilized in obtaining the first image. This image collector can include, for example, an x-ray machine or a device capable of obtaining a digital image (e.g., a digital camera). The system may also include a linking device which creates the necessary link between the first image and the patient code.

A processor may also be part of the system. The processor may include a digitizer for converting the first image into a digital image, assuming the first image is not already a digital image. The processor also includes an output/input device for importing the digitized first image. The processor uses the digitized first image to create supplemental information. Preferably, the processor includes a comparator which compares the digitized first image against preselected criteria using specialized computer algorithms to identify regions or features that appear abnormal. An image generator within the processor generates a second image which highlights any apparent abnormal features. Finally, the system preferably includes a second viewer which is capable of displaying the supplemental information associated with the first image. In preferred embodiments, this means that the second viewer displays a visual representation of the digital version of the second image so that it can be viewed, together with the first image on the first viewer, by the medical analyst. As noted above, the decoder initiates automated retrieval of the supplemental information, such as a second image. This facilitates the medical analyst's ability to concentrate on his or her examination of the first image and the supplemental information.

The present invention also includes methods which enhance the rate and efficiency at which medical analysts can review medical images. In general the methods comprise utilizing a patient code associated with a medical image to automate the retrieval of supplemental information related to the first image which, in conjunction with the first image, can be used by an analyst in conducting a medical analysis.

More specifically, certain methods include displaying a first image on a viewer for viewing by a medical analyst, wherein the first image includes a representation of a patient's body part, or of a specimen taken from the patient, and a patient code which encodes desired information about the patient. The patient code is utilized to automate access to supplemental information concerning the patient. The first image and the supplemental information can then be used by the analyst in conducting a medical evaluation.

The methods of the present invention may include additional steps as well. For instance, the methods may include obtaining the first image which is representative of a patient's body part or a specimen taken from the patient. Methods may also include a linking step in which a patient code is linked with the first image.

The methods may further include a processing step. For those instances in which a digital image is not initially acquired, the processing step may initially involve digitizing the first image. The digital image is then used to generate supplemental information related to the first image. In preferred embodiments, the processing step includes comparing the digitized version of the first image with preselected criteria to identify features of medical concern. The processor then generates a second image which highlights the features which appear abnormal. As noted above, during an analysis session, the analyst displays the first image on a first viewer. The patient code associated with the first image is read or decoded by the decoder and automated retrieval of the supplemental information, preferably a second image, is initiated. The supplemental information is displayed on a second viewer. Thus, the analyst can examine both the first image displayed on the first viewer and the supplemental information on the second viewer in conducting a medical analysis. The second viewer may be part of the same unit as the first viewer or it can be a separate unit. Unlike existing methods, the analyst is not required to input any information to access the supplemental information. In preferred embodiments, the patient code is a bar code, the decoder is a bar code reader and the supplemental information is a second image derived from the first image which highlights features of potential medical concern. The methods and apparatus of the present invention find particular utility in analyzing mammograms. In such instances, the first image is typically an x-ray mammogram and the second image is a digital image derived from the x-ray mammogram which highlights suspicious areas such as masses and/or calcifications.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic view which depicts the major components of the system of the present invention.

FIGS. 2 A and 2B are diagrammatic views which more fully show the components of the processor unit of the system of the present invention (components bounded by dashed lines are optional).

FIG. 2C is a diagrammatic view which more fully illustrates the components of the image analysis center of the system of the present invention (components bounded by dashed lines are optional).

FIG. 3 A is a diagrammatic view of one embodiment in which the decoder is an integral component of the first viewer.

FIG. 3B is a diagrammatic view of an alternate embodiment in which the decoder is not an integral component of the first viewer. FIG. 4A is a perspective view which depicts an embodiment wherein the first viewer and the second viewer exist as separate units.

FIG. 4B is a perspective view which depicts an alternate embodiment in which the first viewer and second viewer are part of the same unit.

FIG. 5 is a diagrammatic view which shows the major steps in a method of the present invention (dashed lines extend to optional steps).

FIGS. 6A and 6B are diagrammatic views which show more fully the different steps encompassed in the processing steps wherein the first image is a non-digital image and a digital image, respectively.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides methods and systems which allow medical personnel to more quickly retrieve information associated with medical images and increase the efficiency of the review of such images and related information in evaluating the existence of disease and the efficacy of treatment. More particularly, the systems of the present invention are useful in situations in which an initial medical image of a body part or of a specimen taken from a patient is obtained and then the first image is used to generate supplemental information which can be used by medical personnel in conjunction with the original image in making a medical evaluation. By associating a patient code with the medical image and the supplemental information, it is possible to use the code to quickly identify, locate and retrieve the original image and supplemental information related to it. Systems of this type find particular utility in the analysis of medical images in the radiology and pathology context. It is envisioned that the systems and methods of the present invention will have special utility in the evaluation of x-ray mammograms against processed images which highlight regions of potential medical significance, such as suspicious masses and/or calcifications.

As used herein, the term "patient code" is defined to mean a series or letters, symbols or designs which represent certain information which cannot be readily interpreted by simple observation of the code. Preferably, the patient code is a bar code. The use of a patient code is in accord with the goal of maintaining patient confidentiality with regard to the medical images examined using the apparatus and methods of the present invention. The specific information encoded by the patient code can vary. As an example, the code could include the patient's I.D. number, age, date of exam and type of image. In the case of mammography, the encoded information would also indicate whether the image is of the right or left breast and whether the image is a top or side view

(medial lateral oblique and cranial caudal views).

The term "supplemental information" is meant to include, but is not limited to, information which is related to the original or first image. Such information may be textual, another image, or a combination thereof. In preferred embodiments, the supplemental information is derived from a computerized analysis of the first image. For example, in certain particularly preferred embodiments, the supplemental information is a second image derived from the original image which has been processed using computer algorithms to highlight regions or features which are indicative of disease or otherwise appear to be medically relevant. However, the supplemental information need not be generated directly from the original medical image.

With reference now to FIG. 1, the system of the present invention may include an image collector 10, a linking device 30, a processor 50 and an image analysis system 70. For non-digital images, the original image may be digitized by a separate digitizer 40 as shown in FIG. 1. Alternatively, the image may be digitized by a digitizer integrated within the processor 50 as described more fully below. As indicated by the dashed lines between these different devices, the devices may be connected with one another so that information or data can be transmitted from one unit to another or they may exist as independent units. Thus, systems of the present invention may include an individual unit such as the image analysis system 70 or combinations of the various units. In general terms, the image collector 10 is used to obtain a first image of a patient's body part or of a specimen obtained from the patient, such that the linking device 30 associates the first image with the patient code. The processor 50 utilizes the first image to create supplemental information which is related to the first image. During processing, the patient code remains associated with the supplemental information. The supplemental information can then be transmitted to the image analysis system 70. The image analysis system 70 displays the first image and utilizes the patient code associated therewith to automate the retrieval and display of the supplemental information so that the first image and supplemental information can be easily viewed and utilized by a medical professional during a medical evaluation. More specifically, the image collector 10 can include a variety of different devices which are capable of acquiring an image or representation of a body part or of a specimen taken from a patient. For example, the image collector 10 may be an x-ray machine which creates an image on x-ray film. A digital camera capable of generating a digital image or representation is a second example of an image collector 10 which could be used. In this case, the first image or representation would be stored as a digital file on some type of data storage medium.

The linking device 30 is a device which is capable of associating a patient code with the first image acquired by the image collector 10. In those cases in which the first image is recorded on x-ray film, the linking device 30 may be a device which uses light to expose the patient code onto the x-ray film. In practice, the code is generally flashed onto the film before the image is acquired. When the first image is a digital image, the linking device 30 is a device capable of incorporating the patient code into the file containing the first image or capable of creating a link between the patient code and the first image file. As shown in FIG. 1 , the first image with its associated patient code is typically transfeπed to a processor 50 which utilizes the first image to generate supplemental information concerning the patient. As noted above, most preferably the supplemental information created by the processor 50 is a second image derived from the first image, although other types of information could be generated.

FIG. 2A provides an example of the major components of the processor 50 in those cases in which the first image is acquired as a non-digital image. An example of this type of case would be when the first image is an image recorded on x-ray film. An input/output device 52 is used to import the first image into the processor 50. The digitizer 54 acts to convert the first image into a digital representation which can be stored as a digital file. The patient code is also digitized and is used in tracking and identifying the first image during processing. As depicted by the dashed lines around the digitizer 54 in FIG. 2A, the digitizer 54 can also exist as an independent unit separate from the processor unit 50.

Once the first image, including the patient code, has been digitized, the digital image is transferred to a comparator 56 which utilizes the digital representation of the first image to generate supplemental information. In a preferred embodiment, the comparator 56 is an optical processor. The comparator 56 may be located in physical proximity with the input/output device, or may be remote. In certain preferred embodiments, the comparator 56 compares the digital representation of the first image with preselected criteria to identify features of potential medical significance. An image generator 58 then generates a second image in which features indicative of disease or which otherwise appear medically relevant are highlighted, e.g., circled electronically. The patient code is also associated with the second image. The resulting second image, including the patient code, is then exported from the processor 50 by the input/output device 52 to the image analysis system 70 (see FIG. 1). In those cases in which the image collector 10 is capable of acquiring a digital image, or in those instances in which the digitizer is separate from the processor unit 50, a digitizer 54 is not required, as shown in FIG. 2B. In such cases, the processor unit 50 need only include the input/output device 52, the comparator 56 and the image generator 58. These components function in the same way as just described in relation to FIG. 2B. Supplemental information such as a second image is transmitted to the image analysis system 70. As illustrated in FIG. 2C the major components of the image analysis system can include a short term data storage unit 76, a first viewer 72, a decoder 74, a second viewer 77 and an archival data storage unit 78. As indicated by the dashed lines in FIG. 2B, the archival data storage unit 78 is optional. The supplemental information which typically exists as a digital image, is initially stored in a short term data storage unit 76, e.g., a computer memory device. When medical personnel are ready to view the first image and the supplemental information, the originally acquired first image (e.g., an image on x-ray film or a digital image) is displayed on a first viewer 72. The first viewer 72 is capable of displaying the first image for viewing by a medical professional, such as a radiologist or pathologist for example. A decoder 74 associated with the first viewer 72 decodes or reads the patient code linked with the first image and initiates retrieval of the supplemental information from a storage device such as the separate data storage unit 76; the supplemental information is then displayed upon a second viewer 77. Any viewer described herein may have image manipulation capabilities, such as context, brightness, magnification, rotation, etc. After the supplemental information is used, it can then be stored for later use in an archival storage unit 78.

The first viewer 72 can be any type of device capable of displaying the first image so that it can be viewed by medical personnel. The first viewer 72 will vary somewhat in design depending upon the form of the first image. In those instances in which the first image is an x-ray image, the first viewer 72 includes the necessary components and lights for backlighting and illuminating the x-ray so that it can be easily viewed by the medical analyst. In those instances in which the first image 82 is recorded as a digital image, the first viewer 72 would include a display unit capable of displaying a visual representation of such a digital image.

In a digital system as described above, supplemental information may be shown on the first viewer 72, such as by being superimposed on the first image. In this case, the second viewer 77 is unnecessary.

FIG. 3 A illustrates the general design of a first viewer 72 in which the first image is recorded on x-ray film. In such cases, the first viewer 72 includes a viewing screen 80 upon which the first image 82 can be positioned and viewed. In certain embodiments, the decoder 74 is built into the first viewer 72 and is located behind the viewing screen 80 so that when the first image 82 is positioned at the spot at which the first image 82 is to be viewed the decoder 74 is centered behind the patient code 86 associated with the first image 82 (the decoder 74 for this situation is shown in solid lines in FIG. 3A). When positioned in this way, the decoder 74 can easily read or decode the patient code 86 while the first image 82 is in a stationary position during viewing by the medical analyst.

Certain viewers 72 made for viewing x-ray films are designed to automatically feed the first image 82 (i.e., an x-ray film) onto the first viewer 72 and to position the first image 82 at a specific location on the viewer screen 80. In general such viewers are designed for medical facilities which analyze a high volume of images. Viewers such as these typically are designed to store a large number of films or images on a first storage reel (not shown) located one side of the viewer 72. By using a foot peddle, the medical analyst can advance an image onto the view screen 80 and then, after analyzing the image, further advance the image off the view screen 80 onto a second storage reel (not shown) located on the side of the viewer 72 opposite that of the first storage reel.

In such embodiments, for example, the decoder 86 may be positioned at a point in advance of the point at which the first image 82 is actually viewed. Thus, the decoder 74 may scan or read the patient code 86 as it passes over the decoder 86 enroute to the viewing location. The location of the decoder 74 in such embodiments is depicted by the decoder 74 represented by the dashed lines in FIG. 3 A. Of course the decoder 74 may be positioned at other locations on the first viewer 72 as well. It is only necessary that the decoder 74 be located at a point at which it can read or decode the patient code 86 either as the image 82 moves across the viewing screen 80 or as it is temporarily stationed at the spot at which the medical analyst views the first image 82.

FIG. 3B illustrates other embodiments in which the decoder 74 is not an integral part of the first viewer 72. Typically, this type of embodiment works best at medical centers which review a lower volume of images. A light pen 74 capable of reading or decoding the patient code 86 is one example of a decoder 74 which can be used in such embodiments. Typically, the light pen 74 is manually passed over the patient code 86 after the first image 82 has been positioned at the site at which the medical analyst views the first image 82.

For first viewers 72 which display digital images rather than x-ray images, the decoder 74 could also form an integral part of the first viewer 72 and be located behind the viewing screen 80 and positioned to be centered behind the patient code 86 when the first image 82 was displayed on the viewing screen 80. A light pen 74 as shown in FIG. 3B could also be used to scan the patient code 86 once the image 82 was displayed on the viewing screen 80.

Regardless of the specific location of the decoder 74, the decoder 74 is electrically connected to the data storage device 76 storing the supplemental information. Hence, once the patient code 86 is decoded or read by the decoder 74, the decoder 74 initiates retrieval of the supplemental information which is associated with the same patient code. As noted above, the supplemental information associated with a particular patient code 86 is displayed on a second viewer 77. The second viewer 77 is capable of displaying a visual representation of the supplemental information. As shown in FIG.

4A, the second viewer 77 may be separate from the first viewer 72, or, as illustrated in FIG. 4B, be an integral part of the first viewer 72.

As illustrated in FIGS. 3A-4B, the patient code 86 is preferably a bar code. In such preferred embodiments, the decoder 74 is a bar code reader or a light pen capable of reading a bar code. In another embodiment of the invention, the first image is of a microscope slide and the viewers 72, 77 (which could just be one viewer) are an appropriate microscope.

In view of the foregoing description of the devices of the present invention, the methods of the present invention become clear. In general, the methods of the present invention comprise utilizing a patient code, preferably a bar code, associated with a medical image to automate the retrieval of supplemental information which is associated with the same patient code so that the medical image and the supplemental information can be utilized in unison by a medical professional in conducting a medical evaluation. Preferably, the supplemental information includes a second image derived from the first image which highlights regions of potential medical significance.

The major steps in the overall process are set forth in FIG. 5. The method begins with an obtaining step 100 in which a first medical image 82 is acquired. The first image 82 once obtained is then linked 120 with a patient code 86 which includes desired information about the patient. In practice, the patient code 86 is generally flashed onto the film before the first image is acquired, in the case where the first image 82 is captured on film. In a displaying step 140, the first image 82 is displayed on a first viewer 72. The patient code 86 associated with the first image 82 is used in a utilizing step 160 to access supplemental information associated with the same patient code 86 and display such information on a second viewer 77. In an optional but preferred processing step 180, the first image 82 is utilized to generate the supplemental information which is retrieved and displayed on the second viewer 77. However, the supplemental information need not be generated during the processing step 180 as shown in FIG. 5. Instead, the supplemental information may be input into data storage and created independently of the first image. Yet in even this situation, the patient code 86 would be utilized to retrieve the supplemental information from a data storage device.

As described above, the obtaining step 100 can include any manner of acquiring a medical image of a patient's body part, or of a specimen taken from the patient. The body part or specimen may include, for example, an organ, a tissue, a cell, a biological fluid, or a sample of one of the foregoing. The obtaining step 100 may include acquiring an x-ray image or a digital image using a digital camera for instance. In the former case, the first image 82 is recorded on an x-ray film; in the latter instance, the first image 82 is a digital representation which is stored as a digital file.

Once the first image 82 is acquired, in the linking step 120 a patient code 86 is associated with the first image 82. In the case of x-ray images, this may involve "flashing" the x-ray with light to expose the patient code 86 onto the x-ray film; in those instances in which the first image 82 is a digital image, the patient code 86 is electronically linked with the digital file containing the digital representation of the first image 82.

Referring now to FIG. 6A, the processing step 180 may initially involve a digitizing step 182 in those cases in which the first image 82 is not acquired in a digital format. During the digitizing step, the patient code 86 is also digitized. Subsequent processing steps may be performed at the site at which the first image 82 was acquired. More typically, however, the first image 82 is transmitted to a separate analysis center in an optional (as indicated by the dashed line) transmission step 184. If the digitized version of the first image 82 is in fact transmitted to a separate site, care is taken to ensure that the transmission lines are secure and checks are performed to make certain that all of the bits comprising the digital file are received by the analysis or processing center.

Once the first image 82 has been digitized, the processing step 180 may further include a comparing step 186 in which the digitized first image 82 is subjected to a computer algorithm which compares the first image 82 against certain preselected criteria to identify features of potential medical significance. In a subsequent creating or generating step 188, supplemental information concerning the first image is generated. As noted above, in preferred embodiments, the supplemental information includes a second image derived from the first image 82 in which features of potential medical significance are highlighted. Regardless of the form of the supplemental information, the patient code 86 remains associated with it.

In those instances in which the processing step 180 and the obtaining step 100 occur at different sites, the supplemental information may be sent back to the site at which the first image 82 was acquired in an optional transmission step 190 (the optional nature of the step is indicated by the dashed line connecting the creation step 188 and the transmission step 190). Again, the proper security checks are made to ensure confidentiality and complete transmission. The supplemental information is typically stored in a standard short term data storage device 76 such as described above until needed. FIG. 6B lists the major steps in those instances in which the first image 82 is initially acquired as a digital image. As can be seen, the steps are identical to those set forth in FIG. 6A, except that a digitizing step is unnecessary because the first image 82 is acquired as a digital image.

When the medical professional is ready to analyze the medical images and the supplemental information for a particular patient, the first image 82 is displayed on a first viewer 72 in a displaying step 140. The different types and designs of first viewers 72 are as described above in relation to FIGS. 3A, 3B, 4A and 4B.

Finally, in a utilizing step 160, the patient code 86 associated with the first image 82 is used to access supplemental information which shares the same patient code 86 from the short term data storage device 76. More specifically, as described in greater detail above, the decoder 74 associated with the first viewer 72 reads or decodes the patient code 86 and initiates automated retrieval of the supplemental information associated with the same patient code 86; the supplemental information is then displayed on the second viewer 77. In preferred embodiments, the supplemental information is a second image derived from the first image 82, wherein features of potential medical significance are highlighted. Regardless of the actual form of the supplemental information, the medical analyst can easily refer to both the first image 82 displayed on the first viewer 72 and the supplemental information such as the second image on the second viewer 77 in making a medical evaluation. The different design arrangements for the decoder 74 and second viewer 77 are as described above in relation to FIGS. 3A, 3B, 4A and 4B.

The present method greatly enhances the speed and efficiency at which medical personnel can review medical images during a medical evaluation, because the methods are designed to associate a patient code 86 with both the original image 82 and the supplemental information. The decoder 74 is able to read the patient code 86 on the first image 82 and initiate automated retrieval of the supplemental information without requiring any input from the medical analyst. Further, the present method allows medical personnel to easily retrieve all images associated with a particular patient code, so, for example, medical personnel can evaluate a current image in comparison with one or more images taken of the same patient at previous times.

In contrast, current methods for reviewing medical images require the analyst to input information to retrieve supplemental information such as a second processed image from a data storage unit 76. Current approaches are also considerably more time consuming, are subject to errors when the analyst inputs information into the data storage device 77 to retrieve supplemental information and do not permit the analyst to focus exclusively on the images being examined.

The present methods also have the advantage of being designed to maintain patient confidentiality. The first image 82 and supplemental information are associated with a patient code 86 which cannot be deciphered by simple visual observation. This differs from cuπent methods in which labels containing the patient's name are frequently used as the means for identifying, tracking and correlating the first image 82 and supplemental information. It is not uncommon for the patient's name to appear directly on the first image and/or the supplemental information. Finally, the methods are compatible with the need for both short term and long term storage of the medical images.

The methods of the present invention have particular utility in the analysis of mammograms. Thus, the use of the general methods described herein will be briefly described in relation to this one specific application. Under current practice, the obtaining step 100 typically involves obtaining an x-ray image of a patient's breasts. Thus, the first image 82 is recorded on x-ray film. Although the mammogram typically is an x-ray image, technology is being developed which will allow the mammogram to be obtained as a digital image. In the linking step 120, a patient code 86, preferably a bar code, is "flashed" onto the x-ray film using devices adapted to expose the patient code 86 onto the x-ray film. Such devices are called "flashers" or "ID stampers" within the field of mammography. For digital mammograms, an input device would be used to link the patient code 86 with the digital mammogram image. As noted above, the patient code 86 could include, for instance, the patient's I.D. number, age, date of exam, whether the image is of the right or left breast and whether the image is a top or side view. It should be understood that the patient code 86 may be placed onto film (or other media) in addition to any other information which may be placed onto the film, such as information which is presently placed thereon. For x-ray mammograms, the mammogram is digitized in a digitizing step 182.

This step would be unnecessary for digital mammograms. Typically, the digitized mammogram would be transmitted to a specialized medical analysis center for processing. In the processing step 180, a computerized algorithm would be used in the comparing step 186 to compare the digitized image with preselected criteria which are indicative of suspicious breast masses and/or calcifications. In the creating step 188, a second image would be generated in which the suspicious masses and/or calcifications were highlighted. Details regarding processors and methods specifically designed for performing an analysis of mammograms are described in U.S. Patent 5,212,637 {"Method of Investigating Mammograms for Masses and Calcifications and Apparatus for Practicing such Method" of Serena, 1993) and U.S. Patent 5,799,100 {"Computer Assisted Method and Apparatus for Analysis of X-Ray Images Using Wavelet Transforms" of Clark, et al., 1998). The foregoing patents are merely examples of mammogram analysis procedures, and any known or future method may be used. The second image, in those instances in which it is generated at a separate analysis center, is subsequently transmitted back to the medical center at which the first image was obtained and stored in the short term data storage unit 76. When the radiologist is ready to review the case, he or she displays the first image 82 on one of the first viewers 72 of the various designs described earlier. Using either a decoder 74 located within the first viewer or alternatively a light pen, the patient code is read. The decoder 74 initiates retrieval of the second image from the data storage unit 76 and the second image is displayed on the second viewer 77 which, as noted earlier, may exist as part of, or be separated from, the first viewer 72. By examining both the first image 82 and the highlighted regions on the second image, the radiologist can evaluate whether the highlighted regions are in fact indicative of disease and/or determine the progress of the disease.

Because the methods of the present invention allow for automated retrieval of the second image, the radiologist is free to concentrate on the analysis rather than having to input information into the data storage unit 76 for each case. The process becomes particularly efficient and rapid in those cases in which the first viewer 72 is designed to automatically advance the mammogram films onto and off of the first viewer 72 as described above.

Although the methods described herein are believed to be particularly useful for the analysis of mammograms, the methods have general applicability to the analysis of medical images or medical specimens that can be imaged of any type. For example, the methods of the present invention could also be used in the analysis of images for pathology.

An aspect of the invention is that the patient code 86 can be used to retrieve medical images that were acquired in previous years, such as those stored in the archival data storage unit 78. For example, a portion of the patient code 86 can represent a patient ID, so that a user can select all or a subset of the images relating to a particular patient. Further, the comparator (preferably including optical processing) can be used to create comparisons between any of the images and thereby find suspicious areas.

It should be understood that patient information other than the patient code (bar code) according to the invention may in general also be displayed on an image. All the patents, publications and other references listed herein are incorporated by reference herein.

Claims

We claim:

1. A method for facilitating the analysis of a medical image which represents a patient's body part or a specimen taken from said patent comprising utilizing a bar code i associated with a first medical image to automate the retrieval of supplemental information concerning said patient.

2. A method according to claim 1, wherein said body part or specimen is selected from the group consisting of an organ, a tissue, a cell and a biological fluid.

3. A method according to claim 2, wherein said body part is a breast.

4. A method according to claim 3, wherein said bar code encodes information selected from the group consisting of the identity of said patient, the patient's I.D. number, patient's age, a date associated with the first medical image, and the type of view such as an indication of whether said medical image is of the right or left breast.

5. A method according to claim 1, wherein said supplemental information includes a second image which is derived from said first image and highlights a feature of potential medical significance, if any.

6. A method for facilitating the analysis of medical images, comprising:

(a) displaying a first image on a viewer for viewing by a medical professional, said first image including a representation of a patient's body part or of a specimen taken from said patient and a patient code which encodes desired information about said patient; and

(b) utilizing said patient code to provide automated access to supplemental information concerning said patient, said first image and said supplemental information being used by said medical professional in conducting a medical evaluation.

7. A method according to claim 6, wherein said patient code is a bar code.

8. A method according to claim 6, wherein said first image is an x-ray film and said viewer includes components for illuminating said x-ray.

9. A method according to claim 6, wherein said first image is a digital image and said viewer is a display unit capable of displaying a visual representation of said digital image.

10. A method according to claim 6, wherein said body part or specimen is selected from the group consisting of an organ, a tissue, a cell and a biological fluid.

1 1. A method according to claim 10, wherein said body part is a breast.

12. A method according to claim 11 , wherein said desired information selected from the group consisting of the identity of said patient, the patient's I.D. number, patient's age, a date associated with the first medical image, and the type of view such as an indication of whether said medical image is of the right or left breast.

13. A method according to claim 6, wherein said utilizing step includes using an external device unconnected to said viewer to decode said patient code.

14. A method according to claim 13, wherein said patient code is a bar code and said external device is a light pen.

15. A method according to claim 6, wherein said utilizing step includes using an internal device located within said viewer to decode said patient code.

16. A method according to claim 15, wherein said patient code is a bar code and said internal device is a bar code reader.

17. A method according to claim 6, wherein said supplemental information includes a second image which is derived from said first image and which highlights a feature of potential medical significance, if any.

18. A method according to claim 17, wherein said first image is of a breast and said highlighted feature includes suspicious masses and/or calcifications.

19. A method according to claim 6, wherein: (a) said first image is an x-ray film and said viewer includes components for illuminating said x-ray film;

(b) said patient code is a bar code;

(c) said body part is a breast; and

(c) said supplemental information includes a second image, said second image being derived from said first image and highlighting a feature of potential medical significance, if any.

20. A method according to claim 6, wherein:

(a) said first image is a digital image and said viewer includes a display unit capable of displaying a visuaLrepresentation of said digital image;

(b) said patient code is a bar code;

(c) said body part is a breast; and

21. A method for facilitating the analysis of medical images, comprising: (a) processing a first image to create a second image, said first image including a representation of a patient's body part or of a specimen taken from said patient and a patient code which encodes desired information about said patient, and said second image being stored in a data storage unit;

(b) displaying said first image on a viewer for viewing by a medical professional; and

(c) utilizing said patient code to provide automated access to said second image, said second image being used by said medical professional in conducting a medical evaluation.

22. A method according to claim 21, wherein said patient code is a bar code.

23. A method according to claim 21, wherein said second image highlights a feature of potential medical significance, if any.

24. A method according to claim 21, wherein said first image is an x-ray mammogram and said second image is a digital image which highlights suspicious masses and/or calcifications.

25. A method for facilitating the analysis of medical images, comprising:

(a) obtaining a first image representative of a patient's body part or a specimen taken from said patient;

(b) linking a patient code with said first image;

(c) displaying said first image on a viewer for viewing by a medical professional; and

(d) utilizing said patient code to provide automated access to supplemental information concerning said patient, said first image and said supplemental information being used by said medical professional in conducting a medical evaluation.

26. A method according to claim 25, wherein said patient code is a bar code.

27. A method according to claim 25, wherein said body part or specimen is selected from the group consisting of an organ, a tissue, a cell and a biological fluid.

28. A method according to claim 27, wherein said body part is a breast.

29. A method according to claim 25, wherein said obtaining step includes taking an x- ray image of said body part or specimen so that said first image is recorded on an x-ray film.

30. A method according to claim 25, wherein said obtaining step includes obtaining a digital image of said body part or specimen such that said first image includes a digital representation of said body part or specimen which is stored in a digital file.

31. A method according to claim 29, wherein said linking step includes forming an image of said patient code on said x-ray film.

32. A method according to claim 30, wherein said linking step includes electronically linking said patient code with said digital file.

33. A method according to claim 25, wherein said supplemental information is a second image derived from said first image and further comprising a processing step, said processing step including a step of creating said second image.

34. A method according to claim 33, wherein said obtaining step includes taking a non-digital image of said body part or specimen so that said first image is formed on a film and wherein said processing step further includes:

(a) digitizing said first image to form a digital representation of said first image;

(b) comparing said digital representation of said first image with preselected criteria to identify a feature of potential medial significance; and (c) creating said second image, said second image highlighting said feature of potential medical significance, if any.

35. A method according to claim 34, wherein said obtaining step is performed at a first facility and wherein said processing step further includes:

(a) transmitting said digital representation of said first image to a second facility, said comparing step and said creating step being performed at said second facility; and

(b) transmitting said second image to said first facility.

36. A method according to claim 33, wherein said obtaining step includes creating a digital representation of said body part or specimen such that said first image includes a digital image stored in a digital file and wherein said processing step further includes:

(a) comparing said digital representation of said first image with preselected criteria to identify a feature of potential medical significance; and

(b) creating a second image, said second image highlighting said feature of potential medical significance, if any.

37. A method according to claim 36, wherein said obtaining step is performed at a first facility and wherein said processing step further includes:

(b) transmitting said second image to said first facility.

38. A method according to claim 25, wherein said utilizing step includes using an external device unconnected to said viewer to decode said patient code.

39. A method according to claim 38, wherein said patient code is a bar code and said external device is a light pen.

40. A method according to claim 25, wherein said utilizing step includes using an internal device located within said viewer to decode said patient code.

41. A method according to claim 40, wherein said patient code is a bar code and said internal device is a bar code reader.

42. A method according to claim 25, wherein said supplemental information includes a second image: (a) said body part is a breast and said patient code is a bar code;

(b) said obtaining step includes taking an x-ray image of said breast so that said first image is recorded on an x-ray film; and

(c) said processing step includes:

(i) digitizing said first image to form a digital representation of said first image;

(ii) comparing said digital representation of said first image with preselected criteria to identify a feature of potential medical significance associated with said breast; and

(iii) creating said second image, said second image highlighting said feature of potential medical significance, if any.

43. A method according to claim 25, wherein said supplemental information includes a second image:

(a) said body part is a breast and said patient code is a bar code; (b) said obtaining step includes creating a digital image of said body part or specimen such that said first image includes a digital representation stored in a digital file; and

(c) said processing step includes: (i) comparing said digital representation of said first image with preselected criteria to identify a feature of potential medical significance associated with said breast; and

(ii) creating said second image, said second image highlighting said feature of potential medical significance, if any.

44. A system for facilitating the analysis of medical images, comprising:

(a) a first viewer which displays a first image for viewing by a medical professional, said first image including a representation of a patient's body part or of a specimen taken from said patient and a patient code which encodes desired information about said patient; and

(b) a decoder which decodes said patient code and initiates automated retrieval of supplemental information concerning said patient from a data storage unit.

45. A system according to claim 44, further including a second viewer for displaying said supplemental information so said supplemental information can be viewed by said medical professional and used in conjunction with said first image in conducting a medical evaluation.

46. A system according tα claim 44, further including a processor which creates a second image, said second image being derived from said first image and highlighting a feature of potential medical significance, if any.

47. A system according to claim 46, wherein said processor includes an optical processor.

48. A system according to claim 44, wherein said patient code is a bar code and said decoder is capable of generating a signal which initiates automated retrieval of said supplemental information from said data storage unit.

49. A system according to claim 44, wherein said first image is recorded on an x-ray film and said first viewer includes components for illuminating said x-ray film.

50. A system according to claim 49, wherein said x-ray is a mammogram.

51. A system according to claim 44, wherein said first image is a digital image and said first viewer is a display unit capable of displaying a visual representation of said digital image.

52. A system according to claim 51 , wherein said digital image is a digital image of a breast.

53. A system according to claim 44, wherein said decoder is an external device unconnected to said first viewer.

54. A system according to claim 53, wherein said patient code is a bar code and said external device is a light pen.

55. A system according to claim 44, wherein said decoder is an internal device which forms an integral part of said first viewer.

56. A system according to claim 50, wherein said patient code is a bar code and said internal device is a bar code reader.

57. A system according to claim 44, wherein said decoder obviates the need for said medical professional to input information into said data storage unit to retrieve said supplemental information.

58. A system according to claim 44, wherein said second viewer is capable of converting a digital representation of said supplemental information to a visual display.

59. A system according to claim 44, wherein said supplemental information is a second image derived from said first image, said second image highlighting a feature of potential medical significance, if any.

60. A system according to claim 44, wherein said first viewer and said second viewer are separate physical units.

61. A system according to claim 44, wherein said first viewer and said second viewer are part of the same physical unit.

62. A system according to claim 44, wherein:

(a) said patient code is a bar code and said decoder is capable of generating a signal which initiates automated retrieval of said supplemental information from said data storage unit;

(b) said first image is recorded on an x-ray film and said first viewer includes components for illuminating said x-ray film; and

(c) said second viewer is capable of converting a digital representation of said supplemental information to a visual display, wherein said supplemental information is a second image derived from said first image, said second image highlighting a feature of potential medical significance, if any.

63. A system according to claim 44, wherein:

(b) said first image is a digital image and said first viewer is a display unit capable of displaying a visual representation of said digital image; and

(c) said second viewer is capable of converting a digital representation of said supplemental information to a visual display, wherein said supplemental information is a second image derived from said first image, said second image highlighting a feature of potential medical significance, if any

64. A system for facilitating the analysis of medical images, comprising: (a) an image collector which obtains a first image representative of a patient's body part or of a specimen taken from said patient;

(b) a device which creates a link between said first image and a patient code which encodes desired information about said patient;

(c) a processor which creates a second image, said second image being derived from said first image and highlighting a feature of potential medical significance, if any;

(d) a first viewer which displays said first image for viewing by a medical professional;

(e) a decoder which reads said patient code and initiates automated retrieval of supplemental information concerning said patient from a data storage unit; and

(f) a second viewer which displays said supplemental information so said supplemental information can be used by said medical professional in conjunction with said first image in conducting a medical evaluation.

65. A system according to claim 64, wherein said patient code is a bar code.

66. A system according to claim 64, wherein:

(a) said image collector is an x-ray machine so that said first image is recorded on an x-ray film; and (b) said first viewer is a viewer which includes components for illuminating said x-ray film.

67. A system according to claim 64, wherein:

(a) said image collector collects a digital image of said body part or specimen so that said first image includes a digital image stored in a digital file; and (b) said first viewer is a display unit capable of displaying a visual representation of said digital image.

68. A system according to claim 65, wherein said linking device is a device which uses light to expose said patient code onto said x-ray film.

69. A system according to claim 64, wherein said linking device is an electronic input device which electronically links said patient code with said digital file.

70. A system according to claim 66, further including a digitizer which digitizes said first image on said x-ray film to form a digital representation of said first image, and wherein

(a) said supplemental patient information is a second image; and

(b) wherein said processor includes: (i) a comparator which compares said digital representation of said first image with preselected criteria to identify a feature of potential medical significance; and

(ii) an image generator which creates said second image, said second image being a digital image derived from said first image which highlights said feature of potential medical significance, if any.

71. A system according to claim 70, wherein said comparator is an optical processor.

72. A system according to claim 67, wherein said supplemental patient information is a second image and wherein said processor includes:

(a) a comparator which compares said first image with preselected criteria to identify features of potential medical significance; and

(b) an image generator which creates a second image, said second image being a digital image derived from said first image which highlights said features of potential medical significance.

73. A system according to claim 72, wherein said comparator is an optical processor.

74. A system according to claim 65, wherein said decoder is a light pen.

75. A system according to claim 65, wherein said decoder is a bar code reader which is physically connected to said first viewer.

76. A system according to claim 70, wherein said second viewer is capable of converting said digital image into a visual display which shows said highlighted feature, if any.

77. A system according to claim 72, wherein said second viewer is capable of converting said second image into a visual display which shows said highlighted feature, if any.

78. A system according to claim 64, further including a digitizer which digitizes said first image on said x-ray film to form a digital representation of said first image, and wherein: (a) said patient code is a bar code;

(b) said image collector is an x-ray machine so that said first image is recorded on an x-ray film;

(c) said first viewer is a viewer which includes components for illuminating said x-ray film; (d) said processor includes:

(i) a comparator which compares said digital representation of said first image with preselected criteria to identify features of potential medical significance; and (ii) an image generator which creates said second image, said second image being a digital image derived from said first image which highlights said feature of potential medical significance, if any; and

(e) said second viewer is capable of converting said second image into a visual display which shows said highlighted feature, if any.

79. A system according to claim 78, wherein said comparator is an optical processor.