A Virtual Simulator Designed
for Collision Prevention
in Proton Therapy
Hyunuk Jung1, Oyeon Kum2, Heechul Park3 and Youngyih Han1,3
Department of Health Sciences & Technology, Sungkyunkwan University1,
Korea Institute of Radiological and Medical Sciences2,
Department of Radiation Oncology, Samsung Medical Center3
Happinovation 2020
SUNGKYUNKWAN UNIVERSITY
SAMSUNG MEDICAL CENTER
Proton Therapy
3D
IMRT
Proton
Source: Department of Radiation Oncology, SMC
Effect of Air-Gap
W/ Airgap
About Three times!!
W/O Airgap
JM Sisterson et al., Distal penetration of proton beams: the effects of air gaps between
compensating bolus and patient, Phys. Med. Biol. 34 1309-1315(1989)
Collision Possibility
Sumitomo
Varian
IBA
Nozzle
Couch / Patient
Collision possibility
btw a Bulk Nozzle and
Couch / Patient
Motivation
• If collision happen, Delay the treatment and
Reduce the clinical efficiency
• Limitation of automatic detection function in planning phase
• Confirmation of the possibility of the collision before treatment setup
User Friendly Virtual Simulator
Methods Three Research Points
Machine (Nozzle)
3D Geometry
Patient
3D Geometry
Treatment Plan
(RTPS)
Treatment Setup
Collision Detection
Methods Three Research Points
✔Virtual Machine
 SolidWorks CAD Software
 CAD Design based on the specification from the manufacturer
SolidWork
Methods Three Research Points
✔Patient Information
 CT, 3D Scanner
 Use scan image to get the information of body contour where
potential collision can occur but CT scanning does not cover
 No More Imaging Dose
Geomagic XOS
Matlab
STL Format
Methods Three Research Points
✔Patient Information
 3D Reconstruction using CT data + Scan data
 Iterative Closest Point (ICT) algorithm
 Within 2 mm accuracy
(a) Head & Neck
(b) Breast
Methods Three Research Points
✔ Treatment Setup & Collision Detection
 SolidWorks CAD Software
 3D Reconstruction to iso-center of treatment room
 Rotation / Translation of Nozzle & Couch based on iso-center
 Overlap Detection for Collision conformation
Collision area
A
B
Iso-center
Methods Three Research Points
✔ Treatment Setup & Collision Detection
 Process of Collision Examination
1. Apply treatment plan
▶ A function of time and movement, i.e. animation)
2. Select two parts want to check a collision
3. Set up frame rate for calculation ( default 8 frame / sec)
▶ No limitation, but time consuming
▶ Precise vs. Speed
4. Calculation for each frame and Check the collision
▶ If collision occurs, show frame number, collision volume, and
collision area
Results Virtual Machine
Gantry 300°
Gantry 90°
Rotation
Couch 0°
Couch 15°
Results Treatment Setup & Collision Detection
(a)
(b)
(c)
(d)
Figure 1. Visualized pictures that create collision between the
virtual patient / couch and the gantry. (a) the illustration of
treatment room, including all components (Gantry Nozzle, Couch
and Patient), (b), (c) two patient – gantry collisions (d) a couch –
gantry collision. (Red color indicates the collision site)
Results Treatment Setup & Collision Detection
Results Treatment Setup & Collision Detection
Conclusions
• Our simulator was Successfully coded and performed
• Now, we are under development of the automatic
directly using input
method
file from RTP
• The developed virtual simulator is going to be connected with RTP,
which will improve clinical efficiency and patient safety
Thank You!
Thanks to Sumitomo Heavy Industries,
which provides us with the specifications
Happinovation 2020
SUNGKYUNKWAN UNIVERSITY
SAMSUNG MEDICAL CENTER
Results Treatment Setup & Collision Detection
Proton Therapy
Methods Overall Flow Chart