WO2007101989A2

WO2007101989A2 - Digital medical image processing

Info

Publication number: WO2007101989A2
Application number: PCT/GB2007/000773
Authority: WO
Inventors: Gareth Richard Beddoe; Ravi Bickram K. Shrestha; Adam David Boyse
Original assignee: Medicsight Plc
Priority date: 2006-03-07
Filing date: 2007-03-07
Publication date: 2007-09-13
Also published as: WO2007101989A3; GB0604610D0; GB2436156A

Abstract

A system for providing medical image processing software components to a medical imaging user, comprising a server providing access for users of the system to a selection of said software components, and a plurality of client applications each providing access to the server for a corresponding said user so as to install a selected said software component at the corresponding client application.

Description

Digital Medical Image Processing

Field of the Invention

[0001] The present invention relates to digital medical image analysis, particularly computer-implemented medical image analysis. Background of the Invention

[0002] Medical images are a valuable tool for diagnosis, and a variety of techniques or modalities have been developed; these include X-ray, computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI). Conventionally, these images have been inspected visually by trained radiographers. The images may be generated digitally (CT and MRI) or digitized from an analog image (X-ray). The digitized images may be inspected and annotated by radiographers, and the annotations stored for later retrieval and analysis.

[0003] The task of the radiographer can be made easier by storing the medical image on a computer providing a user interface which allows the user to manipulate the image and to visualize the structures contained therein in different ways. However, the process is time consuming and must be performed with great care in case any abnormalities are missed. [0004] To replace some or all of the work of the radiologist, Computer Assisted Detection (CAD) software has been designed to analyze the medical image and detect potential abnormalities. The detection can be performed semi-automatically, with some interaction with the radiologist, or automatically, involving no interaction beyond the selection of the image to be analyzed. For example, the applicant's MedicHeart™, MedicLung™ and MedicColon™ diagnostic software perform semiautomatic diagnosis of CT scans of the heart, lung and colon respectively. [0005] CAD software uses one or more algorithms to analyze a given medical image. No one algorithm can analyze accurately all types of medical image. For example, abnormal structures in the lung have different image characteristics from those in the colon. Images taken with different modalities (e.g. MRI, CT, ultrasound) have different resolutions and image characteristics and hence require different algorithms to analyse them. Hence, the user of CAD software identifies the type of medical image (for example, the modality or object of the image) and selects the appropriate algorithm for analysis of that type of image. Alternatively, the user may only be interested in analyzing one type of image and therefore only requires one type of algorithm. [0006] Patent publication WO-A-03/040965 discloses a data mining system for processing medical images, with an architecture that supports plug-in modules whereby new element extraction, element combining and inference algorithms may be installed. The data mining system may be run as a service using the internet. [0007] Patent publication EP-A-1336378 discloses an ultrasonic diagnostic device having a plug-in layer allowing software to be added or changed as desired.

[0008] Currently available digital medical image analysis software typically comprises user interface software and one or more algorithms for performing image manipulation, analysis and/or diagnosis. A user buying a particular software package is typically tied to the algorithms provided with that package, although they may be able to purchase further algorithms from the supplier of the software package. However, such algorithms are rapidly evolving to provide ever-greater accuracy and functionality, and it would be desirable to allow a user to take advantage of new algorithms as and when required. It would also be desirable to allow users greater flexibility and choice of algorithms to use. It would also be advantageous for providers of such algorithms to be able to supply them directly to the end user.

Statement of the Invention

[0009] According to one aspect of the invention, there is provided a system for providing medical image processing software components to a medical imaging user, comprising a server providing access for users of the system to a selection of said software components, and a plurality of client applications each providing access to the server for a corresponding said user so as to install a selected said software component at the corresponding client application. [0010] Preferably, use of the software component at the client application is limited according to one or more predetermined parameters, such as a predetermined number of uses or a predetermined time. The parameters may be updated by communication between the client application and the server. In one example, the user may request a predetermined number of uses of a particular software component, and when that number of uses has been exhausted, may request further uses from the server via the client application. In another example, the user may request use of a software component for a trial period and when that period has expired, may request non-time-limited use of the software component. [0011] This technical arrangement enables a novel business model for digital medical imaging, in which users pay for the use of software components on a per-use basis. This means that users need only pay for the level of use that they need, and allows small independent clinics with limited funds access to the same software components as large healthcare providers. This in turn provides access to new markets for providers of software components, which incentivizes them to produce new and better algorithms. [0012] The software components may comprise medical image processing software, medical image analysis software, and/or medical diagnosis software. [0013] The server may comprise a web portal allowing users to perform one or more of the following:

- download the client application - register as a user

- provide billing information

- select a software component to be installed in the client application

- install the software component in the client application request a licence to use an installed software component - receive a licence key enabling use of the software component according to parameters specified in the license key or otherwise

- view promotional information relating to available software components

- view demonstrations of available software components

- view news and/or information items relating to medical image analysis [0014] The client application may be operable in an online mode, connected to the server, and in an offline mode, disconnected from the server. In offline mode, the client application may be operable to process medical images using installed software components enabled by corresponding license keys. In online mode, the client application may renew licence keys that have expired by requesting new licence keys from the server. [0015] The client application may comprise one or more of: an image viewer for viewing medical images

- a medical image server for connecting to one or more remote image databases so as to receive and/or send medical images

The client application may comprise a web browser including plug-ins and/or extensions for providing the above functionality. The client application may provide a standardized plug-in architecture for the software components. Brief Description of the Drawings

[0016] Specific embodiments of the present invention will now be illustrated with reference to the accompanying drawings, as described below:

Figure 1 is a schematic diagram showing a medical imaging device and a remote computer for processing image data from the medical imaging device;

Figure 2 is a more detailed diagram of the remote computer; Figure 3 is a diagram of a client/server system in an embodiment of the invention. Figure 4 is a diagram of a browser/portal-based architecture of the system. Figure 5 is a diagram of a folder structure for implementing image processing modules in the embodiment.

Figures 6 to 9 are screenshots of a client application in the embodiment.

Detailed Description of the Embodiments

Medical Imaging

[0017] The present invention is applicable to digital medical images. One example of such an image is a CT scan image. A CT scan image is a digital image comprising one or a series of CT image slices obtained from a CT scan of an area of a human or animal patient. Each slice is a 2-dimensional digital grey-scale image of the x-ray absorption of the scanned area. The properties of the slice depend on the CT scanner used; for example, a high-resolution multi-slice CT scanner may produce images with a resolution of 0.5-0.6 mm/pixel in the x and y directions (i.e. in the plane of the slice). Each pixel may have 32-bit greyscale resolution. The intensity value of each pixel is normally expressed in Hounsfield units (HU). Sequential slices may be separated by a constant distance along the z direction (i.e. the scan separation axis); for example, by a distance of between 0.75-2.5 mm. Hence, the scan image may be a three-dimensional (3D) greyscale image, with an overall size depending on the area and number of slices scanned. Alternatively, the scan image may comprise a single slice and therefore be a single two-dimensional (2D) greyscale image. [0018] The CT scan may be obtained by any CT scanning technique, such as electron beam computed tomography (EBCT), multi-detector or spiral scan or any technique which produces as output a 2D or 3D image representing X-ray absorption. [0019] The invention is not limited to CT scan images, but may be applied to other digital medical images, such as MRI, ultrasound or X-ray images. Conventional X-ray images may be developed on an X-ray film prior to being digitized. Computer System

[0020] As shown in Figure 1, the scan image may be created by a computer 104, which receives scan data from a scanner 102 and constructs the scan image. The scan image is saved as an electronic file or a series of files, which are stored on a storage medium 106, such as a fixed or removable disc. The scan image includes metadata associated with the scan image. The scan image may be analyzed by the computer 104, or the scan image may be transferred to another computer 108 which runs software for analyzing the scan image and/or displaying the results of the analysis, as described below. The software may be stored on a carrier, such as a removable disc or a solid-state memory, or downloaded over a network.

[0021] The computer 104 and/or the computer 108 may be a computer system 200 as shown in Figure 2. The present invention may be implemented as programmable code for execution by the computer system 200. Various embodiments of the invention are described in terms of this example computer system 200. After reading this description, it will become apparent to a person skilled in the art how to implement the invention using other computer systems and/or computer architectures.

[0022] Computer system 200 includes one or more processors, such as processor 204. Processor 204 may be any type of processor, including but not limited to a special purpose or a general-purpose digital signal processor. Processor 204 is connected to a communication infrastructure 206 (for example, a bus or network). Various software implementations are described in terms of this exemplary computer system. After reading this description, it will become apparent to a person skilled in the art how to implement the invention using other computer systems and/or computer architectures. [0023] Computer system 200 also includes a main memory 208, preferably random access memory (RAM), and may also include a secondary memory 210. Secondary memory 210 may include, for example, a hard disk drive 212 and/or a removable storage drive 214, representing a floppy disk drive, a magnetic tape drive, an optical disk drive, etc. Removable storage drive 214 reads from and/or writes to a removable storage unit 218 in a well-known manner. Removable storage unit 218 represents a floppy disk, magnetic tape, optical disk, etc., which is read by and written to by removable storage drive 214. As will be appreciated, removable storage unit 218 includes a computer usable storage medium having stored therein computer software and/or data.

[0024] hi alternative implementations, secondary memory 210 may include other similar means for allowing computer programs or other instructions to be loaded into computer system 200. Such means may include, for example, a removable storage unit 222 and an interface 220. Examples of such means may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable storage units 222 and interfaces 220 which allow software and data to be transferred from removable storage unit 222 to computer system 200.

[0025] Computer system 200 may also include a communication interface 224. Communication interface 224 allows software and data to be transferred between computer system 200 and external devices. Examples of communication interface 224 may include a modem, a network interface (such as an Ethernet card), a communication port, a Personal Computer Memory Card International Association (PCMCIA) slot and card, etc. Software and data transferred via communication interface 224 are in the form of signals 228, which may be electronic, electromagnetic, optical, or other signals capable of being received by communication interface 224. These signals 228 are provided to communication interface 224 via a communication path 226. Communication path 226 carries signals 228 and may be implemented using wire or cable, fibre optics, a phone line, a cellular phone link, a radio frequency link, or any other suitable communication channel. For instance, communication path 226 may be implemented using a combination of channels. [0026] In this document, the terms "computer program medium" and "computer usable medium" are used generally to refer to media such as removable storage drive 214, a hard disk installed in hard disk drive 212, and signals 228. These computer program products are means for providing software to computer system 200.

[0027] Computer programs (also called computer control logic) are stored in main memory 208 and/or secondary memory 210. Computer programs may also be received via communication interface 224. Such computer programs, when executed, enable computer system 200 to implement the present invention as discussed herein. Accordingly, such computer programs represent controllers of computer system 200. Where the invention is implemented using software, the software may be stored in a computer program product and loaded into computer system 200 using removable storage drive 214, hard disk drive 212, or communication interface 224, to provide some examples.

[0028] In alternative embodiments, the invention can be implemented as control logic in hardware, firmware, or software or any combination thereof. Client/server System

[0029] In an embodiment of the present invention, there is provided a client/server system for distributing software components for processing digital medical images, as shown schematically in Figure 3. A plurality of computers 108 are connected via a network 302, such as the Internet, to a server which in this embodiment comprises a web server 306 and a back end server 308. Each of the computers 108 executes a client application for processing and displaying medical images, which client application may be downloaded from the webserver 306 or installed from another location. The client application also communicates with the web server 306 so as to implement medical image processing functionality as described in detail below.

[0030] At least one of the computers 108 is further connected to a medical image database 304 which receives, stores and sends medical images. In one example, the computer 108 may download a medical image from the medical image database 304 prior to processing the medical image using the client application. In another example, the computers 108 may exchange medical images via the medical image database 304. The medical image database 304 may index and retrieve medical images according to metadata. The images and metadata may conform to the DICOM (Digital Imaging and Communications in Medicine) standard. [0031] As an alternative embodiment to the client/server system described above, medical image processing software components may be distributed using a centrally controlled peer- to-peer network, such as the BitTorrent™ system.

Web Portal and Client Application Architecture

[0032] In a preferred embodiment as shown in Figure 4, the web server 306 runs a software application that provides a medical image processing web portal 402 accessible by the client applications 404 running on the respective computers 108. The web portal 402 includes a licensing and billing function 406, a main content function 408 and a software update function 410. Each client application 404 includes image processing 416, software update and licensing 418 and online content viewing 420 functions that interact with the web portal 402. The client application 404 may further include an image server 412 which interacts with the image database 304. The client application 404 preferably includes an image viewer 414. [0033] To allow access to the Ml functionality of the web portal 402, users must first register by providing user details to the licensing and billing function 406. The user is preferably required to provide payment information to a payment processing function 426. [0034] The web portal 402 displays, for selection by the user, software components available for download by the client application 404. The registered user may select a component for download, authorise payment for use of the component, and download the component 428 to the client application 404 together with a licence key 430 that determines how the component may be used. The user may then use the software component 428 within the client application 404 to process and/or analyze medical images subject to the limitations imposed by the licence key 430. If the limitations are exceeded, the user may send a license request 432 to the web portal 402; if the request is authorised and any payment that may be required for the licence is authorised, the web portal 402 then sends a new licence key 430 to the client application 404 enabling further use of the component 428 subject to the limitations of the new licence key 430. [0035] In one example, a registered user selects a component 428 for trial use, and downloads that component 428 together with the licence key 430 permitting use of the component on a limited number of images, for a limited number of image processing actions, and/or a limited time. When the permitted use of the component has been exhausted, and the user wishes to continue to use the component, the user authorises payment for the component via the licensing and billing function 406, and receives a new licence key 430 enabling further use of the component. The further use may be unlimited, or may be limited by time, number of images and/or number of processing actions. [0036] The client application 404 may interact with the web portal 402 to detect available updates to components 428 selected and/or installed in the client application. The client application 404 may send a request for updates 434 to the web portal 402, indicating what components 428 are installed, or the web portal 402 may compare records of components 428 installed in that client application with records of components for which updates are available. Available updates to installed components may be downloaded and installed automatically by the client application 404, or the user may be requested to confirm installation of updates, and authorise any payment required for the updates.

Software component architecture

[0037] The client application 404 is preferably implemented as a web browser extension or plug-in allowing installation of the software components 428 as plug-ins using a standard architecture. Figure 5 shows an example of a data structure for implementing this plug-in architecture. A client application directory 502 includes a plug-in directory 504 containing, for each component, an XML configuration file including component details such as:

- component name - vendor information version information

- license key(s)

- location of component DLLs/executable location of help file - pre-processing details

- main processing details

- parameter types

- return types menu information The plug-in directory 504 further contains the component DLLs/executables and help files as indicated in the XML configuration file.

[0038] When the client application 404 is started or updated, it parses the plug-in directory 504 and reads the configuration files to obtain the necessary information to use the installed components 428. The XML configuration format is preferably standardized so that components 428 from multiple different vendors can be installed in the client application 404.

Software component functionality

[0039] The software components 428 may process a medical image, its metadata and/or a derivative thereof. In one example, the component 428 may pre-process a medical image to segment a portion of the image, for example to identify a portion corresponding to the lung or coronary artery. Li another example, the software component 428 may process an unprocessed or pre-processed image to identify and mark the positions and/or extents of a specific type of suspected abnormality in the image. Examples of algorithms for performing such processing are described in the applicant's patent publications WO-A-05/114566, WO- A-05/112769 and WO-A-06/000738. In another example, the component 428 may post- process metadata and/or a medical image to perform an estimated diagnosis. [0040] The component 428 may require one or more input parameters and may output one or more output parameters. These parameters may be input by the user or derived from image metadata. The component 428 may derive optimum input parameters for another component, as described for example in the applicant's pending patent application no. PCT/ GB05/004547.

Client Application User Interface [0041] An example of a user interface for the client application 404 will now be described with reference to Figures 6 to 9. In this example, the user interface is implemented within a browser, such as Microsoft™ Internet Explorer™. Figure 6 shows a welcome page of the web portal 402 displayed by the browser. The following menu options 602 are presented:

- Web portal (i.e. the current page) - File management

Viewer Software mall Licensing Configuration Selection of a menu option displays a corresponding window, as described below.

[0042] Figure 7 shows a file management window comprising a search filter 702 that allows the user to search for images on the image database 304 according to various metadata fields, such as patient ID, patient name, accession number, date of birth, date of image capture and modality (i.e. type of scan). The user may select the image database(s) 304 to search using a database selector 704. Search results 706 are displayed for selection by the user, with the selected images being collected in the user's 'inbox' 708. One or more images may be selected from the inbox 708 for processing 710 or sending 712 to another user.

[0043] Figure 8 shows a viewer window comprising a plurality of panes 802, 804, 806, 808 each containing a view of, or data relating to, the selected one or more medical image(s). The viewer window displays the following viewer menu options 810: Open: opens a selected medical image Close: closes a selected medical image

Annotations: selectively displays or hides annotations on a medical image - Measurements: displays measurements derived from a selected medical image

Info: displays info (e.g. metadata) about a selected medical image - View: displays a selected medical image Processing: lists installed components 428 for selection, so as to process the selected medical image.

Different panes may display processed and unprocessed versions of the same medical image, as described for example in the applicant's international patent application PCT/GB05/002953.

[0044] Figure 9 shows a 'Software mall' window listing the installed software components or modules 902, including their description, version number and .vendor and licensed status. . The window also lists installed modules for which updates are available 904, for selection by the user. The window also displays new modules 906 not yet installed in the client application, for selection by the user. Updates and new modules are only displayed if the client application 404 is in online mode.

[0045] Other options may be presented in the software mall window. For example, the user may select a new module and elect to view further information about the module. The further information may comprise a demonstration of the module in the form of an interactive presentation or a video clip, for example.

Business Method

[0046] The system described above may be used to implement a novel business method for the provision of medical imaging software. The business method involves some or all of the following features: - provision of a plurality of medical image processing software components or modules from different vendors via a common web portal

- establishing platform standards to allow components or modules from different vendors to be installed in the same client application establishing parameter standards to allow medical imaging parameters to be passed between components provided by different vendors

- licensing selected ones of the components to users by means of a limited licence regime, preferably on authorisation of payment by the users allowing users to refresh licenses for components, preferably on authorisation of further payment. Alternative Embodiments

[0047] The embodiments described above are illustrative of rather than limiting to the present invention. Alternative embodiments apparent on reading the above description may nevertheless fall within the scope of the invention.

Claims

1. A method of making available a plurality of different medical image processing components to a user over a network, comprising the steps of: a. listing said available components to the user; b. receiving a selection of one or more of the available components by the user; c. providing the selected one or more available components to the user together with a licence enabling use of the one or more components by the user.

2. The method of claim 1, wherein step c is performed in response to payment authorisation by the user.

3. The method of claim 1, wherein step c is performed without requiring payment authorisation by the user.

4. The method of any preceding claim, wherein the licence enables at least one of a time- limited use, a limited number of uses, or use on a limited number of different images.

5. The method of any preceding claim, further including: d. receiving a request from the user for further use of the component beyond said limited use; e. receiving payment authorisation from the user for said further use; and f. providing to the user a further licence enabling said further use.

6. The method of any preceding claim, further including identifying an update available for the component, and providing said update to the user.

7. The method of claim 6, wherein said update is provided following authorisation of payment by the user for the update.

8. The method of any preceding claim, implemented on a network server.

9. The method of claim 8, wherein the user operates a client application in communication with the server.

10. A method of obtaining access to one or more selected medical image processing components over a network, comprising: a. receiving a list of available said components; b. selecting one or more of said available components; c. receiving the selected one or more available components together with one or more corresponding licences enabling use of the components; d. installing the received components; and e. processing one or more medical images using the installed components as enabled by the corresponding licenses.

11. The method of claim 10, wherein step c is performed in response to payment authorisation by the user.

12. The method of claim 10, wherein step c is performed without payment authorisation by the user.

13. The method of any of claims 10 to 12, wherein the licence enables at least one of a time- limited use, a limited number of uses, or use on a limited number of different images.

14. The method of any of claims 10 to 13, further including: d. requesting further use of the component beyond said limited use; e. authorising payment for said further use; and f. receiving a further licence enabling said further use.

15. The method of any of claims 10 to 14, further including receiving an update available for the component.

16. The method of claim 15, wherein said update is received following authorisation of payment for the update by the user.

17. The method of any one of claims 10 to 16, performed by means of a client application connected to a server over the network.

18. A computer program arranged to perform the method of any preceding claim when executed on a suitably arranged computer.

19. A computer program product comprising the computer program of claim 18, recorded on a medium.

20. A method substantially as herein described with reference to the accompanying drawings.

21. A computer program substantially as herein described with reference to the accompanying drawings.

22. A system for distributing medical image processing components, comprising a plurality of client image processing applications and a source of said medical image processing components, the client applications being arranged for selection and installation of one or more of the components, wherein limited licenses are distributed for use of the installed components, whichrlicenses- are- extendable on request ^~via the" client^" image^" processing applications.

23. A digital medical image processing application, comprising: a. an image viewer; b. means for selecting and downloading one or more images from a remote image database; and c. means for selecting and downloading one or more image processing components from a remote image processing component source; wherein the image viewer is operable to display the downloaded one or more images after processing by the downloaded one or more components.