Note: Descriptions are shown in the official language in which they were submitted.
CA 02325651 2000-11-09
System and Method for Transfer of Medical Images
Field of the Invention
The invention relates generally to medical images, and more particularly to an
Internet based system for the transfer of medical images.
Background of the Invention
1o There is a growing need for universal availability of medical images for
radiologists, physicians and other interested parties who would benefit from
access to
medical images from different medical institutions that may be at different
geographical locations.
Computer systems used for the storage and retrieval of digital medical images
~ 5 are generally known as Picture Archiving and Communication (PAC) systems.
These
systems generally comprise: extensive digital storage capabilities, a
processor for
indexing medical images and workstations, attached through a Local Area
Network
(LAN) for medical image retrieval and viewing. PAC systems are generally
designed
as client-server systems with the workstation containing software to interact
with the
2o PAC system when acting as a client and software to act as an medical image
server
such that the workstation can obtain and display medical images.
There have been efforts to standardize the above systems such that a client
can
interact with multiple servers which each act as a source of medical images.
One
approach considers the standardization of messages and interfaces. The Digital
25 Imaging and Communications in Medicine (DICOM) Standard (protocol) was
introduced in 1985 by the American College of Radiology /The National
Electrical
Manufacturers Association (ACR- NEMA) and is outlined in; ARC-NEMA Standards
Publication No. 300. The DICOM Standard is meant to provide a degree of
universality to the formatting of medical images thereby facilitating
communication
30 of digital medical image information between medical devices, regardless of
the
manufacturer of the equipment on which they were collected. The standard has
been
adopted by most modality and PACs vendors allowing it to become the typical
CA 02325651 2000-11-09
method for exchanging medical-imaging data between two computer systems.
DICOM-compliant medical image archives are ubiquitous at hospitals
throughout the world. A server that comprises medical images that conform to
the
DICOM protocol are generally referred to as DICOM Nodes. DICOM Nodes
interface to modalities, viewing stations and other DICOM-compliant equipment
that
come from different manufacturers. The retrieval of medical images stored
according
to the DICOM Standard requires a DICOM transfer request be placed with the
DICOM Node containing the medical image. The above attributes form what will
be
referred to as a standard DICOM system. The strengths and limitations of a
standard
1 o DICOM system will be known to those of skill in the art.
While the DICOM Standard has been very successful at facilitating
interoperability and information exchange at the hospital-level LAN it does
not
address issues that arise when access to medical image data is needed on a
regional,
national or global scale, such as would be required in a Wide Area Network
(WAN).
t 5 A standard DICOM system does not provide automatic locating of DICOM
medical image archives in a dynamic environment. A DICOM Node's contact
information, i.e., IP address and port number, needs to be added manually to
the
contact lists of all other DICOM Nodes that need to communicate with it.
Therefore,
for example, an archive within which a plurality of medical images are stored
requires
2o the contact information for all viewers to whom it will provide data. It
will be
apparent to those of skill in the art that such a system is not feasible in a
WAN
environment.
Further with the use of a WAN one has the ability to access a plurality of
institutions and servers contained therein that contain medical images. One
would
25 like to efficiently determine which server or servers of the above
plurality of servers
contains the requested medical image without the need to send a separate query
to
every server from which medical images may be retrieved. This process which is
currently required for a standard DICOM system does not efficiently scale up
to the
WAN level.
3o The Internet and its suite of communications protocols has become a widely
used WAN. That essentially standardizes the protocols for the distribution of
information over a wide area. While sometimes being used for the purposes of
2
CA 02325651 2000-11-09
sharing information locally (at the institutional LAN level) the Internet's
main
strength is the ability to distribute and share information globally (at the
world WAN
level). The built-in scalability of the Internet as a distribution channel
that naturally
facilitates universal accessibility of information (°'anywhere at
anytime") is a strength
of the Internet that many other electronic information distribution solutions
including
standard DICOM lack. Therefore it is apparent that a system for the
distribution of
information over a wide area could beneficially access the capabilities
provided by the
Internet.
There are a variety of circumstances in which access to medical images from
outside the institution in which they are stored is beneficial. The
circumstances are
associated with the requirements of various health care professionals
including;
radiologists, physicians and researchers. It will be apparent to one skilled
in the art
that this list is not meant to be exhaustive. Rather it is representative of
the needs of
various professionals in the medical community. Some exemplary current and
near-
~ 5 term relevant clinical needs will now be discussed.
Radiologists often use and sometimes rely upon prior imaging studies of a
patient to best interpret the imaging information associated with the current
study.
These prior studies may occasionally reside in DICOM-compliant archives in
other
institutions. In the case of standard DICOM, radiologists who want to access
medical
2o images from multiple imaging facilities have to have each facility install
and allow
them to use a "virtual private network" to access that facilities DICOM
medical image
archives. The radiologist then configures their reading and viewing station to
access
the DICOM medical image archives in all the facilities. Making the above
system
work reliably and securely involves technical challenges and may often not be
a
25 practical solution. While virtually all current DICOM medical image
archives offer
some kind of Internet-based access, such access is either unsuitable for
effective
interpretation, or it requires using a proprietary viewer, which may be
different for
each institution serviced by the radiologist. Thus the Internet based
capabilities are
far from standardized and do not access the full capabilities of the Internet.
30 Physicians constitute a second group of professionals that often require
ongoing access to a patient's medical images. This access may span weeks or
months
after the imaging study and often from a number of different physical
locations and
CA 02325651 2000-11-09
institutions. Remote access to the imaging information may also be required
for tele-
consultation and e-conferencing between physicians. Such conferencing would
greatly benefit from standard DICOM information and facilitate the 3D post-
processing of DICOM medical images at the physician workstation. Non-DICOM
methods that allow referring physicians access to medical images across the
Internet,
e.g., by converting them to GIF or JPEG medical images, do not provide the
DICOM
information required for 3D post-processing.
Medical researchers would also benefit from wide access to medical images
and the broad range of pathological information there within. Such access may
be
freely permitted if all patient identification has been removed. Insurance
adjusters
may also benefit from access to medical images related to a given claim in
order to
assess its validity.
Finally, with the growing "patient empowerment" trend, patients will often
request access to their own imaging information. Since patients will almost
always be
~ 5 remote from the DICOM Nodes that contain the medical images Internet
accessibility
would be beneficial. Further, patients may wish to tele-consult with experts
across the
Internet. This may often require that the experts will have access to the
patient's
medical images before rendering an opinion. Implementation of a life-long
patient
record requires ubiquitous access to medical images over long periods of time.
20 Moreover, a standard DICOM system is not suited for the distribution of
imaging information over the Internet. Systems that have been developed
providing
this capability are often cumbersome and do not fully access the capabilities
provided
by the Internet. On the other hand, medical image distribution solutions
developed for
the Internet are based on the use of proprietary technologies and thus are
only suited
25 for users who choose to work with one vendor. They do not leverage the
capabilities
and standardization of DICOM, the leading medical imaging communication
standard.
Therefore, there is a need for a system for the transferring of medical images
that follow the DICOM Standard beyond local area networks within institutions,
for
3o which the DICOM Standard is well suited. The system would preferably use
the
Internet and its suite of communications protocols. The system would also
implement
4
CA 02325651 2000-11-09
security measures allowing the secure distribution of medical information
across the
Internetto authorized users.
Summary of the Invention
It is an object of the invention to provide a novel system and method for the
transfer of medical images across a wide area network that obviates or
mitigates at
least one of the disadvantages of the prior art.
In accordance with one aspect of the invention a system for transferring one
or
more medical images between two or more local area networks across a wide area
network is presented. The system comprises; one or more image storage servers
a list
server and one or more client computers.
In accordance with another aspect of the invention a system for transferring
15 medical images over a wide area network is presented. The system comprises;
two or
more local area networks, each local area network comprising a collection of
one or
more medical images, the on or more medical images being comprised by one or
more
image storage servers and the one or more medical images conform to a common
image storage and retrieval protocol, one or more clients being able to
request one or
2o more medical images and a local area network server being connectable to
the wide
area network, and a list server for providing a list of one or more medical
images
available from the image storage servers and contact information for the local
area
network servers, the list server being connectable to the wide area network.
25 In accordance with another aspect of the invention a local area network
that
forms an element of a system for transferring one or more medical images over
a wide
area network is presented. The local area network comprises; one or more
computers
acting as clients within the local area network, one or more image storage
servers
comprising the one or more medical images that conform to a common image
storage
3o and retrieval protocol, and a local area network server, the local area
network server
providing an interface between the local area network and a wide area network
to
which the local area network server is connected to and in communications
with, the
CA 02325651 2000-11-09
local area network server maintaining a list of image storage servers within
the local
area network containing medical images.
In accordance with another aspect of the invention a list server that is an
element of a system for transferring one or more medical images across a wide
area
network I presented. The list server comprises; a list of one or more medical
images
comprised by one or more image storage servers of local area networks that are
elements of a system for transferring medical images, a directory comprising
contact
information for multiple local area network servers of local area networks
that are
elements of a system for transferring medical images, and a connecting unit
for
connecting to the wide area network for communicating with the two or more
local
area network servers.
In accordance with another aspect of the invention a method of requesting one
~ s or more medical images that conform to a common image storage and
retrieval
protocol within a system for transferring one or more medical images across a
wide
area network is presented. The method comprising the steps of; receiving a
query by
a local area network server from a requesting client who is an element of the
same
local area network as the local area network server, the query being in
accordance
20 with a common image storage and retrieval protocol, analyzing information
provided
in the query by the local area network server of the local area network of the
requesting client, contacting a list server by the local area network server
of the local
area network of the requesting client, receiving from the list server a list
of one or
more medical images comprised by the system for transferring medical images
which
25 are available to and are of interest to the requesting client, and
returning the list of
available medical images to the requesting client.
In accordance with another aspect of the invention a method of transferring
one or more medical images that conform to a common image storage and
retrieval
3o protocol from a first local area network that comprises one or more medical
images
and a local area network server to a second local area network that comprises
one or
more clients and a local area network server across a wide area network is
presented.
CA 02325651 2000-11-09
The method of transferring one or more medical images comprises the steps of;
receiving a selection of a one or more medical images which conforms to the
common
image storage and retrieval protocol, contacting a list server of the wide
area network
by the local area network server of the second local area network, providing
contact
and security information by the list server of the wide area network to the
local area
network server of the second local area network, contacting the local area
network
server of the first local area network by the local area network server of the
second
local area network using the contact and security information, retrieving the
requested
one or more medical images by the local area network server of the first local
area
network, and forwarding of the one or more medical images retrieved from the
first
local area network to the second local area network via the external network.
In accordance with another aspect of the invention a method by which a list
server facilitates the transfer of one or more medical images across a wide
area
t 5 network is presented. The method comprising the steps of; receiving a
query from a
local area network server of a client requesting one or more medical images,
forming
a list of one or more medical images comprised by the system for transferring
medical
images, returning the list of one or more medical images to the local area
network
server of the local area network that comprises the client requesting the one
or more
2o medical images, and providing contact and security information to the local
area
network server of the local area network that comprises the client requesting
one or
more medical images.
Brief Description of the Drawings
The invention will be described with reference to the accompanying drawings,
wherein:
Figure 1 is a schematic diagram illustrating the networks of the medical image
transfer system of the current invention;
3o Figure 2 is a schematic diagram that illustrates details of the networks
presented in Figure 1;
Figure 3 is a flow chart of the query process performed during a request for
the
CA 02325651 2000-11-09
transfer of medical images; and
Figure 4 is a flow chart of the medical image retrieval process performed
during the transfer of medical images.
Detailed Description Embodiments of the Invention
The currently preferred embodiment presents a system and architecture for
transferring medical images that conform to the DICOM protocol from one local
area
network to another, remote local area network. In the currently preferred
embodiment
to the transfer between local area networks occurs across the Internet via a
third party
entity that will be referred to as the Internet DICOM Access Service or IDAS.
IDAS
provides clients access to medical images contained in servers that are
elements of the
medical image transfer system of the current invention pending the proper
security
measures have been provided.
15 A description of the architecture of the system of the currently preferred
embodiment will now be provided. The basic architecture of the networks
encompassed by IDAS is illustrated schematically in Figure 1. The system can
be
generally divided into three groups of resources that are generally formed as
networks
of computers. These networks may include any combination of clients and
servers.
2o Network 102 generally represents a wide area network. In the currently
preferred embodiment external network 102 is substantially formed by the
Internet
and uses the communications protocols of the Internet including the Internet
suite of
communications protocols (TCP/IP, SSL, etc.). Network 102 further comprises
resources that are external to any medical institution, clinic or
practitioner's office that
25 are elements of IDAS such that they are visible to multiple institutions.
Networks 104.1 and 104.2 generally represent networks within entities such as
hospitals, radiology or other imaging clinics and or government agencies and
will be
referred to as institutional networks. It will be apparent to one skilled in
the art that
the above list of institutions containing such networks is not necessarily
complete but
30 rather exemplary of the organizations that may contain clients requesting
DICOM
medical images and DICOM Nodes that may provide medical images to IDAS.
Networks 106.1 and 106.2, which will be referred to as clinic networks,
CA 02325651 2000-11-09
generally represent entities such as a sole practitioner's office or a small
clinic that
will request and supply medical images to IDAS. These entities may comprise
either a
single computer or a small network of computers that may include personal
computers
that are connected to a server. The number of resources in either networks
106.1 or
106.2 is generally smaller than that contained in institutional network 104.1
or 104.2.
Networks 104 and 106 are generally local networks which form Local Area
Networks (LANs) and are generally found in institutions or clinics,
respectively, that
comprise a plurality of clients and servers that request and provide medical
images,
respectively. Networks 104 and 106 are connected to the Internet through any
appropriate connection. Internet connections envisioned by the current
invention
include, but are not limited to wireline phone services, including ISDN and
DSL,
cable services or wireless services. Each of the above networks that are
elements of
IDAS will now be discussed in greater detail.
Details of the above three networks are presented in Figure 2. For purposes of
presenting the currently preferred embodiment the medical image transfer
system will
comprise one institutional network 204 and one clinic network 206. In the
currently
preferred embodiment institutional network 204 comprises three basic elements
or
groups of resources. Client computers 208.1 and 208.2 are local 'stations'
within
institutional network 204 from which clients can view medical images 220.1 and
220.2 that are stored in archives (image storage servers) 212.1 and 212.2,
respectively.
Clients can view medical images from the same local network of which they are
a
member or request medical images from other local area networks through
network
202. Archives 212.1 and 212.2 are servers that provide medical image storage
capabilities for institutional network 204 in which they are located. Archives
212.1
and 212.2 form DICOM Nodes within institutional network 204. In the currently
preferred embodiment archives 212.1 and 212.2 are servers which are capable of
storing large quantities of data as is generally associated with medical
images. Such
servers and the capabilities required of them would be known to those of skill
in the
art.
Local area network server 210 of institutional network 204 is designated as
its
"IDAS Node". IDAS Node 210 is also known as a DICOM proxy node. An IDAS
Node is a server within a local area network such as institutional network 204
that
CA 02325651 2000-11-09
manages a cluster of DICOM archives (Nodes) 212.1 and 212.2 and serves as the
interface between institutional network 204 and network 202. IDAS Node 210
appears as a regular DICOM Node to the other elements of institutional network
204
and as a proxy server and firewall to external network 202 used to transfer
medical
images between local networks. IDAS Node 210 further maintains a local list of
all
DICOM Nodes within the institutional network of which it is a member. Each
IDAS
Node 210 is responsible for periodically querying each local DICOM archive,
212.1
and 212.2, to establish a list of all medical images currently located on
DICOM Nodes
of institutional network 204 of which it is an element.
1o Network 202 is substantially formed by a wide area network to which
networks 204 and 206 are connected and in communications with. In the
currently
preferred embodiment this wide area network is the Internet. The wide area
network
of the currently preferred embodiment contains two types of communications
links.
Links 205 are high bandwidth links that are used for communication of medical
t 5 images amongst IDAS Nodes. Links 203 are low bandwidth links that are used
for
communication of control data between IDAS Nodes and list server 214, which is
also
comprised by network 202. Network 202 also comprises list server 214 that will
be
referred to as the IDAS Directory.
Communications link 203 provides low bandwidth communications between
2o IDAS Nodes 210 and 216, and IDAS Directory 214. C'.ommunications link 203
will
therefore be used for low bandwidth communications including medical image
location and bibliographic information. Communications link 205 provides for
high
bandwidth communications amongst IDAS Nodes 210 and 216. In the currently
preferred embodiment link 205 is a dedicated high-speed link to the Internet
25 "backbone". Communications link 205 would therefore be used for the
transfer of
medical images between IDAS Nodes 210 and 216. Communications link 205 may
comprise other communications links that are suited to high bandwidth
communications such as 1SDN and DSL. Communications links 203 and 205 will
both be elements of the Internet. The current invention encompasses any
suitable
3o communications link as would be apparent to one skilled in the art.
IDAS Directory 214 acts as a centralized resource for the IDAS Nodes and
facilitates the transferring of DICOM compliant medical images across the
Internet.
CA 02325651 2000-11-09
IDAS Directory 214 comprises a central list of medical images contained within
the
networks of IDAS. This list is updated by the IDAS Nodes with information they
obtain during the periodic querying of DICOM Nodes.
IDAS Directory 214 further comprises a database containing information on
each medical imaging study contained within DICOM Nodes of institutional
network
204 and clinic network 206 and each IDAS Node of the medical image transfer
system of the current invention. The medical imaging study information
comprises
unique identifiers (referred to as "Study Instance UIDs" in DICOM) of patient
studies
managed by the IDAS Nodes in institutional and clinic networks, 204 and 206,
1o respectively. IDAS Directory 214 further comprises contact information for
each
IDAS Node - namely for each patient study accessible through IDAS there is a
reference to the IDAS Node from which the study can be retrieved (e.g., the
network
address and the DICOM Application Entity Title of that node). In the currently
preferred embodiment where the wide area network to which the all IDAS Nodes
are
connected is the Internet, contact information may also comprise a Universal
Resource Locator (URL) of each of the IDAS Nodes. IDAS Directory 214 contains
access control information for each patient study listed within it to ensure
that only
the authorized users have access to a a given patient study. This information
comprises; client name, client group name (multiple clients assigned a single
security
2o token), IDAS Node name and IDAS Node group name (multiple IDAS Nodes
assigned a single security token). IDAS Directory 214 is a single entity at
the logical
level but it is implemented as a distributed architecture similar to DNS of
the Internet.
Therefore, IDAS Directory 214 acts as a distributed repository of information
about
all IDAS Nodes connected to and in communication with the system of the
current
invention. It further acts as a distributed repository containing information
about all
medical images managed by all IDAS Nodes.
Clinic network 206 generally represents local area networks of individual
users or small clinics. In the currently preferred embodiment network 206
comprises
3o computer 216, that forms an IDAS Node and client computer 218. Clinic
network
206 may be distributed, where central IDAS Node 216 may be a regional node to
which a plurality of remote clients 218 are connected and in communication
with.
CA 02325651 2000-11-09
Such a regional IDAS Node would be maintained by an IDAS administrator. In an
alternative embodiment clinic network 206 may only comprise a single computer
in a
clinic or practitioner's office which would act as both the IDAS Node and
viewer of
clinic network 206. While the communication between IDAS Nodes may use
DICOM the currently preferred embodiment uses proprietary protocols that are
optimized for the transfer of data on the Internet. Communication between IDAS
Nodes and the IDAS Directory uses standard DICOM.
Communication of medical images between IDAS Node 210 and clients 208.1
and 208.2 and between IDAS Node 210 and image storage servers 212.1 and 212.2
of
1o a given institutional network 204 may be conducted using standard DICOM
protocols
and links that are common to such networks as would be apparent to those of
skill in
the art. Similarly the transfer of medical images between IDAS Node 216 and
client
218 of network 206 uses standard DICOM. Further communication with third-party
software is also conducted using standard DICOM protocols. In the currently
~ 5 preferred embodiment communication between IDAS Nodes of different
networks
across external network 202 uses proprietary protocols that are highly
optimized for
medical image transfer via the Internet while maintaining DICOM information.
Furthermore, the proprietary protocol may support additional value-enhancing
services, such as e-conferencing or consultation, expert referral directory,
emergency
20 over-read service, or even a Computer-Aided Diagnosis (CAD) service that
marks
suspected lesions on the overlay of medical images as they pass through the
system.
Thus system of the currently preferred embodiment uses standard DICOM
protocols for the transfer of medical images within an institutional network
and
translates the medical images into a proprietary format. for communications
between
25 IDAS Nodes i.e. across the Internet.
The methods associated with the transferring of medical images using IDAS
will now be considered. The first stage of the process of transferring medical
images
using IDAS is the formation of a query and execution of security protocols.
This
stage of medical image transfer is shown in the flow chart presented in Figure
3. A
3o client wishing access to DICOM medical images contained in a DICOM Node
that is
an element of the IDAS system of the current invention and is outside of the
network
of which the client is an element sends a single regular DICOM query at step
330 to
12
CA 02325651 2000-11-09
IDAS Node 210 or 216 of institutional network 204 or clinic network 206,
respectively, with which the client is associated. This query contains client
information including; client name, client group and a password that will
determine
the extent of authorized access within IDAS for the requesting client. The
supplied
client information is analyzed at step 332 by the IDAS Node with which the
client is
associated to determine if additional information is required. Each IDAS Node
will
have current access requirements that are in agreement with other IDAS Nodes
of the
system. If additional client information is required the client will be
prompted at step
334 for the additional information. This additional information is then
analyzed to
1 o determine the scope of authorized access for the requesting client. When
sufficient
information has been provided for determination of a given client's access the
IDAS
Node with which the requesting client is associated contacts IDAS Directory
214 at
step 336. IDAS Directory 214 establishes a list at step 338 of available
studies that
match the request and are within the client's scope of access, based on the
client's
i5 identification information. This list is returned to the client at step 340
via the IDAS
Node with which the client is associated as part of the standard DICOM
Query/Retrieve protocol. The currently preferred embodiment, through the use
of
central IDAS Directory 214, allows file transfer across an external network
without
the manual addition of DICOM IP address and port number to contact lists.
Further,
20 only a single query need be sent from the IDAS Node associated with
requesting
client to IDAS Directory 214.
A flow chart of the medical image retrieval process is presented in Figure 4.
The requesting client selects a study or medical images that they would like
to retrieve
from the list of appropriate available studies returned at step 340, at step
450. The
25 IDAS Node with which the requesting client is associated then interacts
with IDAS
Directory 214 at step 452 and obtains the contact information of the image
storage
server's proxy IDAS Nodes) at step 454. IDAS Directory 214 also returns a
security
code at step 454 that will allow the IDAS Node with which the client is
associated to
request the selected study from the IDAS Node of the local area network that
3o comprises the selected study. The IDAS Node with which the client is
associated
accesses the image storage server's (DICOM Node comprising the requested
medical
images) proxy Node at step 456 at which time study retrieval is initiated. The
server
13
CA 02325651 2000-11-09
proxy Node retrieves the requested study or medical image data from the image
storage server containing the requested data using standard DICOM at step 458.
The
retrieved study or medical image data is then forwarded to the requesting
client's
proxy (IDAS) Node at step 460 via the Internet using a proprietary image
storage
protocol. The 1DAS Node then relays the medical images to the client's viewer
using
standard DICOM.
Prior to delivery of an image to a requesting client i.e. after step 460, IDAS
determines what, if any, patient information should be obscured from the
requesting
client. In the currently preferred embodiment there are two levels of access a
client
1 o may have with respect to patient information comprised by the medical
images. In
one level of access the client may have so called 'full' access where all
study and
patient information is presented to the requesting client. In another level of
access
specific patient information is obscured from the medical image and or
associated
study record before presentation to the requesting client. Information
including, but
not necessarily limited to, patient name, patient address and referring
physician is
obscured from the medical image prior to delivery to the requesting client in
this level
of access. The process of obscuring information is performed by the IDAS Node
of
the local area network comprising the image storage servers that are providing
the
medical images. Information related to the level of access of a requesting
client is
2o provided by the IDAS Directory to the IDAS Node of the local area network
comprising the image storage servers that are providing the medical images.
It is envisioned that alternative embodiments of the invention may provide
different levels of access with respect to patient information comprised by
the medical
images. In another level of access any information that would disclose a
patient's
identity may be removed. Other levels of patient information may be a function
of
clients use of the medical images and any applicable laws in either the
jurisdiction of
origin for the medical images or the jurisdiction of the requesting client.
These and
other alternative embodiments are encompassed by the current invention.
The currently preferred embodiment was described with reference to a specific
3o number of clinic and institutional networks that each had particular number
and
configuration of computers and/or other elements. It will be apparent to one
skilled in
the art that the exact number of clinic and institutional networks can be
varied within
14
CA 02325651 2000-11-09
the scope of the current invention. Further, the configuration of client
viewers and
archive servers can be varied within a given network and still lie within the
scope of
the current invention.
In an alternative embodiment the medical images may be stored accordingly to
protocols other than DICOM. Such protocols will be apparent to those of skill
in the
art.
In another alternative embodiment the wide area network used in the transfer
of medical images may be formed by a network other then the Internet. Such
wide
area networks and their use will be apparent to those of skill in the art.
1 o While the invention has been described according to what is presently
considered to be the most practical and preferred embodiments, it must be
understood
that the invention is not limited to the disclosed embodiments. Those
ordinarily
skilled in the art will understand that various modifications and equivalent
structures
and functions may be made without departing from the spirit and scope of the
15 invention as defined in the claims. Therefore, the invention as defined in
the claims
must be accorded the broadest possible interpretation so as to encompass all
such
modifications and equivalent structures and functions.
