Distributed Architectures for Medical Systems Andrew A. Kitchen Computer Integrated Surgery 8 March 2001

Plan of Attack Brief outline of Polaris Tracking Device CORBA IDL project Why efficient usage of distributed architectures in a medical situation is beneficial How such an architecture can be implemented Conclusion

Introducing a Polaris Tracker to the World Creation of a CORBA IDL & Client/Server software to enable efficient networking of a Polaris Tracking Device

The Polaris Device Efficient Optical Tracker Communicates via an RS232 port Already has C++ code written for it It is available in the ERC and is vital for other ERC endeavors

The TINI Device Communicates via an RS232 port & an Ethernet port Dedicated board with sufficient RAM & speed Runs JAVA Cheap & Small

The IDL Negotiates Everything It will allow the Polaris to talk to client through the TINI It runs on a TINI in a JAVA environment It is independent of client platform Client/Server code handle all data acquisition

Plan of Attack Brief outline of Polaris Tracking Device CORBA IDL project Why efficient usage of distributed architectures in a medical situation is beneficial How such an architecture can be implemented Conclusion

The Big Picture Multiple monitoring devices per patient Multiple devices per procedure Few doctors with limited capacity to integrate information

Where’s the Problem? How to manage many devices, and do it within a limited space? How to integrate multiple sets of data into a coherent representation of what is happening? How to manipulate data in a fast & efficient manner? How many devices can be handled at once? Will each device be able to integrate with the other devices? Is there a standard? How much will it cost?

A Sufficient Implementation of a Distributed Medical System Should…. Manage multiple devices and do it without incorporating too much of a footprint Provide quick & efficient data collection from all devices Allow for centralization of control & data management Scalability Adhere to / set recognized standards Be economical!

Plan of Attack Brief outline of Polaris Tracking Device CORBA IDL project Why efficient usage of distributed architectures in a medical situation is beneficial How such an architecture can be implemented Conclusion

A Sample Implementation Katehakis, D.G., et al. “A Distributed, Agent- Based Architecture for Acquisition, Management, Archiving and Display of Real-Time Monitoring Data in the Intensive Care Unit”, FORTH-ICS/TR- 261, October 1999.

Design of an ICU Distributed Architecture

Overall Structure of Architecture The Acquisition Agents run on servers on the network Acquisition Agents are continuously querying the device for current data The Monitoring Agents run on clients on the network Monitoring Agents occasionally query the Acquisition Agents for current data

CORBA Handles the Interaction of the Clients and the Servers

What does this gain us? Frees client resources Allows for significant expansion of network to include numerous servers & devices Provides a common communication protocol (CORBA) Makes possible integration of data from multiple devices on a single client Functions well in real-time due to dedicated server querying

What about the holes in the armor? Every device must have an associated acquisition agent, which must run on a computer (although it need not be dedicated to one device if it has enough I/O ports) CORBA isn’t used by 100% of the developers, but it is used by a vast majority Extra computers take up space Extra computers cost a lot of money

Plan of Attack Brief outline of Polaris Tracking Device CORBA IDL project Why efficient usage of distributed architectures in a medical situation is beneficial How such an architecture can be implemented Conclusion

Smaller, Cheaper & More Universal TINIs are very, very cheap ($57 - $67) TINIs are, well, tiny TINIs have Ethernet & RS232 ports TINIs run JAVA, which is available for free JacORB is a free CORBA ORB coded in JAVA The development tools for the JAVA code is free

Polaris, TINI & CORBA TINI is a dedicated server that runs JAVA The JacORB runs on the TINI board Creation of an IDL and client/server functions for the Polaris Tracker for use with the JacORB allows the TINI to communicate with the Polaris Tracker and with the clients on the network TINI operates as a dedicated server running a single Acquisition Agent and controlling a single device

What’s the Big Deal? Creating an IDL and the associated client/server code for the Polaris Tracker would prove the viability of replacing dedicated workstations with smaller and cheaper TINI boards. Using a JAVA implementation of the CORBA ORB and client/server functions would provide a strong impetus for future development using the TINI, possibly leading to the acceptance of JAVA as an industry standard for networking medical devices in a distributed architecture