METHOD FOR DATA COMMUNICATION INVOLVING MESSAGE FILES CREATED BY STANDARD-COMPLIANT EQUIPMENT

Abstract: A method to deliver standard-compliant messages between locations utilizing conventional transmission pathways (16) without requiring a direct link between standard-compliant devices, or to deliver a standard-compliant message to a non-compliant recipient for subsequent use or manipulation of that data. A store-and-forward process is used while emulating the standard-compliant association between originating (12) and receiving (20) sites. A standard-compliant device operatively associated with the originating site transmits a formatted message file that is received by a network access device (NAD) located at the originating site (14), with that NAD simulating the presence and configuration of a selected compliant device (perceived as a recipient device by the transmitting device). Packaging is added to the message file for transmission over a suitable pathway to the destination site's NAD (18), which simulates the presence and configuration of a selected originating device in order to open an association and deliver the message file to a destination device, software application, or other intended recipient.

Description: METHOD FOR DATA COMMUNICATION INVOLVING MESSAGE FILES CREATED BY STANDARD-COMPLIANT EQUIPMENT CROSS-REFERENCE TO RELATED APPLICATIONS This application is related to copending U.S. Patent Application Serial No. 08/631,540 filed on April 12, 1996 and entitled Method for Conveying Data Between a Plurality of Geographically-Remote Sender and Recipient Sites. The specification of that application including the content of its file history and the prior art discussed or cited therein are incorporated herein by reference as though fully set forth. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to electronic communication of medical-related information between geographically-remote user sites, and particularly to the transmission of medical images and related information originally formatted in an equipment interface standard via a communication pathway using network access devices (NADs) capable of simulating the operation of the corresponding standard-compliant equipment. 2. Discussion of the Prior Art Within the past few years, the transmission of medical images and dedicated "store- and-forward" systems to archive and process related data has become relatively commonplace in a variety of technologically-progressive medical environments. Different departments within a hospital or medical center will frequently be networked together to share patient information, and remote sites may also be linked to the network for importing data such as medical images (X-ray, MRI, ultrasound, and so forth) as well as storing and retrieving patient records. Transmission of patient records and medical images between remote sites (such as a rural physician's office and a metropolitan hospital or specialist's facility) for consultation or referral has also gained greater acceptance in recent years. Previously, the transmission of medical images and related data was known to the field, but was significantly restricted to dedicated or "closed" network systems. In particular, image acquisition and archiving in the electronic domain using magnetic or optical media was earlier recognized as a necessity by radiologists and related practitioners. Diagnostic applications using medical images in the electronic domain have lagged significantly behind the transmission or storage and retrieval functions, however practitioners are beginning to accept that medical images in the electronic domain retain sufficient data for diagnostic purposes, and are amenable to significant advantages in handling, display, computer-aided analysis, and post-diagnosis manipulation and processing. Specialized medical information management systems and databases were developed for using and retaining this data, with each being adapted for a particular organization or facility and the equipment being used. In addition, each manufacturer of diagnostic or imaging equipment traditionally utilized a proprietary format or protocol, and custom interfaces were required to permit equipment from different vendors to connect to the same network or medical information management system. Beyond image acquisition equipment, each manufacturer of display equipment, workstations, archiving or storage systems, and output devices utilized different protocols and interfaces, and data being input to or output from a medical information management program required extensive filtering and reformatting to be compatible with other peripherals or databases. Consequently, the National Electrical Manufacturers Association (NEMA) established a uniform protocol for medical equipment interfaces referred to as the Digital Imaging Communication In Medicine (DICOM) Standard. DICOM defines the interface which permits any DICOM-compliant medical imaging device or related equipment or computer system to communicate directly with one another and exchange medical images or data. DICOM serves as a specification which manufacturers use when designing a product, and has two levels of application: connectivity (message exchange standards responsible for establishing connections and exchanging properly structured messages so an information object sent by one application will be completely received by another) and interoperability (the ability to process and manipulate those medical images or objects). DICOM defines several image objects on which certain "services" can be performed or applied. These services form the basis for DICOM-compliant applications for medical images transmitted between devices, although DICOM does not standardize the underlying image acquisition parameters themselves. Connectivity between two pieces of equipment is evaluated via a "conformance statement" defining or describing the data format and image handling capabilities of the receiving device. The conformance statement also conveys some (but not all) of the information relevant to interoperability, and consequently "plug-and-play" capabilities between two devices cannot be ensured by the DICOM Standard at the interoperability level except for very simple applications. While the DICOM Standard has proven useful for communicating medical images and related data between directly linked image-acquisition and image-processing devices, its compliance requirements can restrict the options available for transmitting medical images or data between remote locations in a generic format capable of cross-modality use or manipulation by a recipient, or via conventional wide bandwidth data transmission pathways (i.e., proprietary pathways, WANs, the Internet, and so forth) that involve steps such as encryption, fragmentation, serialization, remote archiving, or appending transmission, routing, tracking, or commerce-support information to the file. Data or medical images are also transmitted as discrete objects, rather than grouped together as complete patient files or electronic envelopes containing data of distinct types, sizes, data depths, acquisition or transmission parameters, and so forth. Moreover, while a data processing terminal or personal computer may be equipped with a program permitting DICOM messages to be received for subsequent review, use, or manipulation by an individual, a destination DICOM device may itself only be open to receiving strictly-formatted DICOM messages, and may "block" the transmission of any message that is not a strictly-formatted DICOM message to any subsequent personal computer or user connected on that network path. BRIEF DESCRIPTION OF THE INVENTION The present invention provides a method to deliver DICOM message files between geographically remote locations from one DICOM compliant device to another utilizing conventional transmission pathways without requiring a direct link between those DICOM devices. In addition, it provides a method to deliver DICOM message files from a DICOM compliant device to a non-DICOM recipient for subsequent use or manipulation of associated medical images and data. A store-and-forward process is used while emulating the DICOM association dialog between the originating and receiving sites. In other words, the originating site transmits a DICOM message file that is received by a network access device (NAD) located at or reasonably near the originating site, and the NAD simulates the presence and configuration of a selected DICOM compliant device. As such, in addition to enhancing network processing of DICOM messages between traditionally dedicated DICOM devices, the NADs may serve as gateways or filters so that messages may be transmitted to or shared by DICOM devices which would not otherwise be capable of directly communicating with one another, to the extent that partial or complete image content can be interpreted by a DICOM device if supplied by the NAD with appropriate DICOM formatting instructions. Packaging is added to the DICOM message file for transmission over a suitable pathway, and the resultant file is then sent across the pathway to a destination site's NAD. The destination site's NAD simulates the presence and configuration of a selected originating DICOM device in order to open an association with the ultimate destination DICOM device (or recipient's software application) and deliver the complete DICOM message plus any other relevant data incorporated into the package or file. The simulation actions are transparent to both DICOM devices. It may be appreciated by those skilled in the art that the system and method of this invention permits transmission of DICOM-formatted messages between dedicated DICOM- compliant devices via a variety of alternate network connections which include any suitable transmission pathway. In addition, the system permits connecting DICOM-compliant devices to a local area network (LAN) without blocking or interrupting the flow of DICOM and non- DICOM data on that LAN, and permits workstations, personal computers, and peripheral devices to be connected in series or parallel with DICOM-compliant devices which are capable only of sending or receiving strictly-formatted DICOM messages. Some of the additional features and advantages of this system and method include the capability to implement DICOM across a normal wide area network (WAN). Direct connection of DICOM devices across a WAN can tie up the originating work station during the time it takes to send data and wait for confirmation. With the method of this invention, the data is transferred to the originating NAD across the LAN at LAN speeds, thereby freeing the workstation, the professional using that workstation, and possibly the workstation's storage resources in a more time-efficient manner. Ultimate destination devices do not have to be "up" or operational at all times for messages to be transmitted, due to the store and forward process facilitated by the NAD connections. This structure allows DICOM message files to be stored at either the originating NAD or the destination NAD. In contrast, the conventional "point-to-point" configuration requires the originating DICOM site to poll the destination DICOM site periodically to determine when the destination becomes active. While the destination DICOM site is inactive, the corresponding workstation storage resources are also unavailable. Only after the destination DICOM site becomes active can the sending process be initiated and the storage resources utilized. The system and method of this invention negates these limitations or deficiencies at both the origination and destination sites. The majority of DICOM devices currently placed in service by a variety of manufacturers (except databases) can only open one association at a time. In other words, one DICOM device can talk to one and only one other DICOM device at a given instant. If a DICOM message file needs to be sent to multiple locations — for example, an archive and a consulting physician — the sending process must be performed multiple times. In contrast, the system and method of this invention allows for rapid transfer to the originating NAD, which then can open associations with multiple destination DICOM devices (or destination NADs) and move the data to them simultaneously without tying up the originating DICOM device or its associated LAN. DICOM messages can be routed in any manner desired, including secure or private single destinations, multiple or batch- processed transmissions to one or more sites, publish-to-many-site transmissions, or combinations thereof. Grouped message files can be separated or divided and forwarded to the appropriate recipients according to operator instructions, or predetermined routing codes entered into a database associated with the originating or recipient NAD or as a service provided by the operator of the transmission pathway. The operator of the transmission pathway can provide adjunct services, such as off-site archiving, encryption, billing, and a variety of other services. A related advantage is that multiple workstations at a medical site can simultaneously open an association with the originating NAD. This increases efficiency by eliminating the bottleneck which occurs in point-to-point applications. Thus, none of the workstations are waiting for another workstation to: (1) establish an exclusive link to the DICOM device, (2) complete their sending or receiving process, or (3) terminate their exclusive link. Because the originating and destination NADs may be linked to the same standard transmission pathway, a commercial transaction-tracking or verification service can scan the DICOM message for selected elements, thus providing an entirely distinct method for monitoring imaging costs or equipment usage by medical institutions, insurers, and other users. Resources such as tracking or billing capabilities and verification services operate without slowing message transfer rates, and are transparent to users. The system also provides a heightened level of security for verifying image integrity, archiving and retransmitting images, and preventing network tampering. If desired, individual destination locations can be locked in or out — thus preventing inadvertent or unauthorized transmissions to other locations, or dictating that certain transmissions only go to a specified destination — to safeguard patient confidentiality and enhance administrative oversight. The system also permits a greater degree of flexibility and customization regarding security and oversight. Security may be implemented individually on a message- by-message basis, or depending upon factors or criteria such user identification, patient classification, message content, departmental or organizational distinctions, or other levels or schemes as may be desired by a particular facility or network administrator. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a diagram of a basic communication pathway between two DICOM- compliant devices serving as sender and recipient of a formatted message, with originating and destination network access devices (NADs) simulating operation of the sender and recipient devices; and Figure 2 is a diagram showing a more complex communication pathway than that of Figure 1, with multiple recipient sites and additional post-transmission devices or applications. DESCRIPTION OF THE PREFERRED EMBODIMENTS The system and method for transmitting or communicating "standard-formatted" messages of this invention are shown in Figures 1 and 2 and described herein with reference to those Figures, as well as the appended software description, and the system and method are referenced generally herein by the numeral 10. In this specification, the Digital Imaging Communication In Medicine (DICOM) Standard is utilized as a representative example in practicing the system and method 10, however it may be readily appreciated that the system and method 10 of this invention may be utilized with a wide variety of other standards or protocols depending upon the particular type of image or data being transmitted and the sending and recipient applications. Referring particularly to the Figure 1, an originating DICOM device 12 is operatively and sequentially connected to an originating network access device (NAD) 14, a wide area network (WAN) 16 or other electronic communication or transmission pathway of any type conventionally known or hereafter developed, a destination NAD 18, and the destination DICOM device 20. The originating NAD 14 simulates any one of many receiving DICOM devices 20, and the destination NAD 18 simulates any one of many originating DICOM devices 12. A peripheral device 22 such as a workstation or personal computer can similarly be connected to the originating NAD 14 or the destination NAD 18 via a network (LAN) connection at the corresponding site. The peripheral device 22 may be connected directly to the NAD 14, 18 in parallel with the corresponding DICOM device 12, 20, or in series with that DICOM device 12, 20. Depending upon the capabilities of the particular DICOM device 12, 20, the peripheral device 22 or the DICOM device 12, 20 may be the intermediate in a series connection, but where a personal computer or workstation is the peripheral device 22, it is preferably the intermediary connected directly to the NAD 14, 18. One or more DICOM devices 12, 20 physically situated either proximately or remotely relative to the NAD 14, 18 may be operatively connected to that NAD 14, 18 using a LAN, WAN, or other connection that is suitable and appropriate for the particular facilities, uses, and circumstances. In some situations, the ratio of DICOM devices 12, 20 to NADs 14, 18 may be 1 :1 or nearly 1 :1, or several DICOM devices 12, 20 located at physically remote locations within a single complex, at adjacent facilities, or even spread around a region such as a campus or small town can share a single NAD 14, 18. The DICOM standard specifies that the data stream is a value representation of all the patient information including images "as is." The original DICOM message file from the originating DICOM device 12 is kept intact as it is processed through the originating NAD 14 and transmitted via the pathway 16, however a "packaging layer" or "electronic envelope" is added that provides transportation cues, display information, database field information, and any other applications or functionality dictated by the transmission system. A further description of representative methods and systems for the transmission of such information between geographically remote sender and recipient sites is disclosed in U.S. Patent Application Serial No. 08/631,540 filed on April 12, 1996, which is incorporated herein by reference as though fully set forth. Applications are added to specify ultimate source and ultimate destination information, as well as other relevant information regarding content or transmission instructions. Information needed to open the association is captured and validated against predetermined criteria, and may be modified, appended, or replaced as desired (for example, by the service provider 24) to accomplish intended results regarding the message transmission or receipt, device compatibility, security, transaction processing, and so forth. In particular, the transfer syntax (specifying information such as the level of service class: Network Image Transfer, Network Print Management, etc.) is captured to negotiate an association with the receiving endpoint, whether it is the destination DICOM device 20, terminal, personal computer, or peripheral device. The system 10 also captures all information that deals with the format of the data in order to deliver the display parameters to the ultimate destination DICOM device 20. While the DICOM message information is being stored on the originating NAD 14 or destination NAD 18, the system 10 scans the DICOM message for data in selectable DICOM elements. The data in these elements are logged to a transaction history data file associated with the current DICOM message data set being transferred. This data can be used to provide billing based on some variable such as total megabytes transferred, or megabytes per patient ID, per insurance provider, per modality, per department, and so forth. Any one or multiple DICOM elements can be selected, and private data elements are similarly supported by adding them to the scan list. Referring particularly to Figure 2, it may be appreciated that multiple originating DICOM devices 12 may be connected to one or more originating NAD 14 at the sender's location, either independently or through a LAN, and the originating NAD 14 may also serve as or be incorporated into a connection to other elements of the LAN such as workstation terminals, personal computers, and a variety of peripheral devices 22 for data storage, image display, printing or plotting, and so forth. In addition, the originating NAD 14 may be operatively connected via the transmission pathway 16 to an unlimited number of destination NADs 18, each of which may operatively connected to a destination DICOM device 20 or to other peripheral devices 22. It may be readily appreciated that a group of message files or objects such as medical images or patient data (designated a, _>, c, d,...) may be obtained from several originating DICOM devices 12 through one originating NAD 14, and subsequently transmitted to and received by separate destination NADs 18 and distinct destination DICOM devices 20 or peripheral devices 22. Each destination NAD 18 also serves as an originating NAD 14 for messages transmitted in the opposite direction, and any pattern or array of file message source and recipient sites may be accommodated. Message files may be transmitted singularly, in bulk transmissions to one site, or in a publish-to-many-sites format. In this embodiment, four DICOM devices 12 representing exemplary modalities (film digitizer, digital radiography unit, scanner, and ultrasound) all can open associations with the first originating NAD 14. Originating NAD 14 sends the data across the transmission pathway 16 to the DICOM devices 20 or peripherals 22 representing distinct exemplary modalities associated with the second and third destination NADs 18. Associations are opened between the destination NADs 18 and their associated destination peripherals 22. The file a from the film digitizer 12 goes to the archive 22 at the third destination NAD 18, the file b from the digital radiography unit 12 goes to the viewing station 22 at the third destination NAD 18, the file c from the scanner 12 goes to the 3-D display 22 at the second destination NAD 18, and the file d from the ultrasound imaging device 12 also goes to the viewing station 22 at the second destination NAD 18. The film digitizer 12, digital radiography unit 12, scanner 12, and ultrasound imaging device 12 may be strictly-formatted DICOM-compliant devices 12, or alternately may be peripherals 22 attached to the originating NAD 14 which received DICOM-formatted message files (such as medical images) directly from a DICOM device 12 or via another source. Similarly, the archive 22, viewing station 22, and 3-D display 22 may be peripheral devices 22 capable of receiving DICOM-formatted message files (such as medical images) in addition to non-DICOM messages, or strictly-formatted DICOM-compliant devices 12 capable of receiving only DICOM-formatted message files. A service provider 24 may connect to the network pathway 16 to access the NADs 14, 18, as well as to control or monitor the transmission of message files. The service provider 24 may perform a wide variety of functions in addition to establishing, operating, and managing the communications pathway 16 (in the case of a proprietary or dedicated pathway 16), such as routing message files, archiving images and patient data, and tracking and billing expenses for the use of equipment 12 or the transmission of message files. The service provider 24 may accomplish tracking and billing functions by scanning the packaged message or electronic envelope as it is transmitted via the network pathway 16, or the originating NAD 14 or destination NAD 18 may be capable of scanning relevant information from outgoing or incoming message files and storing that information in a database for later acquisition by the service provider 24 or an operator on the associated LAN. The transmitted message files may be archived at the NAD 14, 18 sites, or in a remote location, such as the facility of the service provider 24, with billing or tracking information appended to the files or culled from the archived files for later processing. What is claimed is:

Claims: 1. A method for transmitting a message file between a first standard-compliant device located at an originating site and a second standard-compliant device located at a destination site over a network pathway, said method comprising the steps of: providing a first network access device operatively connected to the first standard- compliant device and to the network pathway; providing a second network access device operatively connected to the network pathway and to the second standard-compliant device; and transmitting the message file between the originating site and the destination site, wherein said first network access device simulates the presence of the second standard-compliant device to facilitate the first standard-compliant device sending the message file to the destination site via said first network access device and the network pathway, and wherein said second network access device simulates the presence of the first standard-compliant device to facilitate the second standard-compliant device receiving the message file via said second network access device and the network pathway. 2. The method of claim 1 wherein the first network access device simulates the presence and configuration of the first standard-compliant device. 3. The method of claim 1 wherein the second network access device simulates the presence and configuration of the second standard-compliant device. 4. The method of claim 1 wherein the first network access device simulates the configuration of a distinct standard-compliant device. 5. The method of claim 1 wherein the second network access device simulates the configuration of a distinct standard-compliant device. 6. The method of claim 1 wherein the first standard-compliant device is a DICOM device. 7. The method of claim 1 wherein the second standard-compliant device is a DICOM device. 8. The method of claim 1 wherein a service provider is operatively connected to the network pathway, said service provider implementing selected procedures relating to the message file. 9. The method of claim 8 wherein the selected procedures implemented by the service provider include routing the message file from the originating site to the destination site. 10. The method of claim 8 wherein the selected procedures implemented by the service provider include generating transaction information regarding the transmission of the message file. 11. The method of claim 8 wherein the message file initially has a standard- compliant format and the selected procedures implemented by the service provider include modifying said standard-compliant format. 12. The method of claim 8 wherein the selected procedures implemented by the service provider include archival storing of the message file. 13. The method of claim 8 wherein the selected procedures implemented by the service provider include storing and retrieving the message file for retransmission. 14. The method of claim 8 wherein the selected procedures implemented by the service provider include storing and retrieving the message file for delayed transmission. 15. The method of claim 8 wherein the message file is sent by a sender and intended for a recipient, and further wherein the selected procedures implemented by the service provider include performing security functions limiting the ability to receive or access the message file to said recipient. 16. The method of claim 8 wherein the selected procedures implemented by the service provider include tracking information regarding usage characteristics of the first standard-compliant device. 17. A method for transmitting a message file from an originating site to a destination site over a communication pathway, said message file having a standard- compliant format associated therewith at either said originating site or said destination site or both, said standard-compliant format being at least partially representative of the configuration of a selected standard-compliant device, said method comprising the steps of: providing a network access device operatively connected to the communication pathway at the originating site, or a network access device operatively connected to the communication pathway at the destination site, or both; and transmitting the message file between the originating site and the destination site, wherein one or both of said network access device operatively connected to the communication pathway at the originating site or said network access device operatively connected to the communication pathway at the destination site simulates the presence and configuration of the selected standard- compliant device to facilitate the transmission of the message file via the communications pathway. 18. The method of claim 17 wherein a standard-compliant device is operatively connected to the communications network at the originating site, and wherein the network access device operatively connected to the communication pathway at the originating site captures information regarding the configuration of said standard-compliant device to facilitate establishing a communication association with the network access device operatively connected to the communication pathway at the destination site for transmission of the message file. 19. The method of claim 17 wherein a standard-compliant device is operatively connected to the communications network at the destination site, and wherein the network access device operatively connected to the communication pathway at the destination site captures information regarding the configuration of said standard-compliant device to facilitate transmission of the message file to said standard-compliant device. 20. The method of claim 17 wherein a first standard-compliant device is operatively connected to the communications network at the originating site, the network access device operatively connected to the communication pathway at the originating site capturing information regarding the configuration of said first standard-compliant device to facilitate establishing a communication association with the network access device operatively connected to the communication pathway at the destination site for transmission of the message file, and wherein a second standard-compliant device is operatively connected to the communications network at the destination site, the network access device operatively connected to the communication pathway at the destination site capturing information regarding the configuration of said second standard-compliant device to facilitate establishing a communication association with the network access device operatively connected to the communication pathway at the originating site for transmission of the message file.

Inventors: BROWN KELLY J, GIEBLER MARK J, BROWN, KELLY, J., GIEBLER, MARK, J.
Applicants: WAM & EXCL, WAM&EXCL
Application year: 1998
Main classification: G06F9
IPC codes: G06F9