Varian Medical Systems Receives FDA 510(k) Clearance For A New Version Of Helios IMRT Treatment Planning Software | Varian

Varian Medical Systems Receives FDA 510(k) Clearance For A New Version Of Helios IMRT Treatment Planning Software

PALO ALTO, Calif., - June 17, 2002 - Varian Medical Systems, Inc. (NYSE: VAR)today announced it has received 510(k) clearance from the U.S. Food and Drug
Administration (FDA) to market a rapid new version of its inverse treatment
planning software for SmartBeam® IMRT.  The new Helios® 6.5 runs
on the company's Eclipse® platform, introduced last year to expedite and
improve the quality of radiation treatment planning in a Windows
environment.  It will be exhibited at the American Association of
Physicists in Medicine (AAPM) meeting in Montreal, July 14-18, 2002.

 "This new version of Helios brings all of the power, speed, and industry
leading features of our Eclipse platform to the inverse treatment planning
process for IMRT," said Tim Guertin, president of Varian Medical Systems'
oncology business.  "Now three-dimensional conformal radiation therapy,
brachytherapy, and IMRT can all be planned on the same workstation."

Helios 6.5 is an inverse treatment planning tool that calculates an optimal
way of filling a radiation oncologist's prescription specifying the radiation
dose levels for a tumor and dose constraints for the surrounding healthy
tissues.  Helios on the Eclipse platform incorporates several new
features and enhancements that improve the speed and accuracy of IMRT
treatment planning.  The software maintains its easy-to-learn,
user-friendly graphical interface.  It automates a number of complex
functions, including organ contouring and segmentation, which help doctors
work with three-dimensional diagnostic images to create prescriptions for
radiation treatment.  Helios incorporates a smart template library of
dose-volume constraints for clinical cases that routinely require inverse
treatment planning.  Doctors can add customized templates to the library
as they are developed. 

Interactive Optimizing

Helios performs millions of calculations to optimally fulfill the radiation
dose prescription accurately and in the shortest possible amount of time. With
Helios 6.5, users can freely change any parameter while the optimization is
taking place, making adjustments to the plan "on the fly."

"Helios displays the results of the optimization as it progresses in real
time. Users can modify the dose-volume constraints and immediately observe the
impact on the dose-volume histogram," said Corey Zankowski, PhD, treatment
planning product manager.  "Without the interactive user-interface, the
physician would have to wait until the entire optimization process was
finished before evaluating the results.  That takes a lot of time.
 With Helios, since many dose-volume combinations can be evaluated in a
single optimization session, you can do a better job clinically in less time."

Helios 6.5 incorporates a very fast optimization algorithm.  The program
can optimize a nine-field head and neck IMRT plan in less than 20 minutes a
task that can take many hours with other kinds of inverse treatment planning
systems.  Helios can plan for the treatment of multiple targets
simultaneously, or the delivery of high and low dose in separate regions of a
single tumor as easily as it plans for a single uniform target.

Flexible Interfaces and Full Integration

The new version of Helios provides a comprehensive set of verification and
quality assurance tools for verifying dose distributions, as well as tools for
commissioning an entire IMRT system.  The program also incorporates an
open architecture capable of exchanging information with other radiotherapy

Helios is now fully integrated with Varian's Vision™ product line, so
that patient plan data is shared with XimaVision (for simulation), VARiS 6.5
(for treatment), and PortalVision (for treatment verification).  As an
integral part of the Eclipse platform, Helios offers users all of the powerful
Eclipse planning tools for inverse planning tasks.  Helios and Eclipse
provide a common user interface, making it easier to learn how to operate the

IMRT and Inverse Treatment Planning

IMRT is an advanced form of cancer radiotherapy that deliver high radiation
doses directly to tumors while sparing more of the surrounding healthy
tissue.  The number of cancer centers offering SmartBeam IMRT from Varian
Medical Systems more than doubled to 100 in 2001, and has since grown to 140

With IMRT, doctors specify the desired radiation doses for tumors as well as
the exposure constraints for surrounding healthy tissues and organs. 
Inverse treatment planning software determines the optimal way to modulate the
radiation beam's intensity during a treatment by working backward through a
complex range of radiation delivery options.  It then produces the
electronic instructions that guide the treatment equipment.

Varian Medical Systems will begin shipping the new Helios 6.5 in late July,
2002.  For more information, call 800-544-4636 or 650 424-5700 or visit