A Web interface to cloud-based
Monte Carlo simulations
for TrueBeam and C-linac
Jong In Park
M.S. student
http://radiotherapyresearchtools.com
Contents
 What is the Virtual Linac
 Application of Virtual Linac
 How can we use (register) ?
Background
Varian provides ‘just’ phase space file for TrueBeam simulation
• Field-independent components were not open to the public
- Target, ion chamber, carousel
Purpose of Virtual Linac
Varian has developed a cloud based web application, called “Virtual Linac”
Linac Monte Carlo simulation as service
- Enable the research community
- Validated geometry (by Varian)
- Fast computing is available w/o server
Now updating ..
2013. 05. 06 version 84 (open to the public)
~ 2013. 11. 18 version 94
http://radiotherapyresearchtools.com
Simulation Mechanics
Amazon Web Service
User
Elastic compute cloud 2
Input file
Dose distribution
Run MC simulation
http://radiotherapyresearchtools.com
Use Case 1 – General case
Virtual Linac
Check a plan
DOSXYZnrc
Dose distribution
http://radiotherapyresearchtools.com
Virtual Linac Graphic User Interface
http://radiotherapyresearchtools.com
Validation of Simulation Results
Presented in ‘AAPM’ meeting
- Simulation results were well matched with measurement
http://radiotherapyresearchtools.com
Use Case 2 – What can we change ?
Treatment head
Investigate changes to the treatment head
- Low energy, medium energy, high energy, imaging,
- Custom is also available
http://radiotherapyresearchtools.com
Use Case 2 – What can we change ?
Originally, in TrueBeam simulation
Virtual Linac
Can define “Target”
Using carbon target
Use Case 2 – Treatment head
Flattening filter
- Open port (FFF), 4X, 6X, 8X, 10X, 15X, 18X, 20X
Location of writing phase space file
- above the jaw
- below the mylar
- isocenter
- 95 cm from source
- 150 cm from source
http://radiotherapyresearchtools.com
Use Case 3 – TrueBeam Developer mode
• Dose distributions from TrueBeam Developer Mode XML file
- non-Monte Carlo expert
• What exactly is Developer Mode?
- A method to control all motion axes and imaging through
customized XML scripts
Image by Varian
Use Case 3 – TrueBeam Developer mode
Still to come !
TrueBeam
Developer mode ‘xml’
http://radiotherapyresearchtools.com
How can we use (register) ?
Requirements
① Send an email to – Daren Sawkey (Varian Medical Systems)
- expression of register
How can we use (register) ?
Requirements
② IP address as seen by the outside world (google “what’s my ip”)
How can we use (register) ?
Requirements
③ Amazon Web services account number
• You can sign up for the Amazon Web Services (AWS) at aws.amazon.com.
• After the sign up, click my account
• The AWS documentation is great, and available at
aws.amazon.com/documentation/ec2 for EC2.
How can we use (register) ?
Requirements
④ A completed license agreement
He or she has the power and authority
Varian the opportunity to review a draft copy of
the proposed publication or presentation for
review and approval at least 45 days prior to..
How can we use (register) ?
Once the register, you can get started
- Log in to AWS
How much is it?
Payment ! When ?
Between Amazon web service and users
- Running the instance (Table)
- Data transfer
On-demand instance
Unit: $
 “Linux” is cheaper than “window”

Can save cost reduced to 1/10 by using ‘spot request’ (highly recommend)
Summary
• Varian validated geometry of component
- Full TrueBeam simulation is available
• Fast parallel computing
• TrueBeam developer mode will be soon
• Reasonable cost with ‘spot request’
• More detail information http://radiotherapyresearchtools.com
Thank you for your attention !