Download - Volumetric modulated Arc-Therapy
3D - CRT
Rectum
Prostate
Overdose
• 4 beams: 2 AP/PA +2 lateral beams
• Overdosage in bladder / rectum limits dose which can be delivered to tumor volume
From 3D - CRT (appeared in 1995-not anymore “modern” )
3D - CRT = 3D Conformal Radiation Therapy
PROSTATE EXAMPLE
Source: Amethyst management
From 3D - CRT to IMRT
“Control” of dose deposition still coarse
Target conformity
3D - CRT IMRT
3D - CRT = 3D Conformal Radiation TherapyIMRT = Intensity Modulated Radiation Therapy
• With IMRT up to 6-8 beam directions
• Still risk of overdosage in bladder/ rectum
PROSTATE EXAMPLE
Source: Amethyst management
IMRT technology (2000)
IMRT = Intensity Modulated Radiation Therapy
• IMRT Prostate showing five beams
• Dose distribution better than the 3D-CRT method but still high dose in bladder/ rectum
• Treatment time of about 10 minutes
Source: Amethyst management
“Control” of dose deposition still coarse
Target conformity
PROSTATE EXAMPLE
IMRT
VMAT = Volumetrically Modulated Arc Therapy
VMAT technology (used since 2009*)
• Beams, coming from 360 directions
• Highly conformal dose distribtution
• Only 2 minutes treatment time
Target conformity
Source: Amethyst management
PROSTATE EXAMPLE
VMAT
VMAT demo
From 3D - CRT to IMRT to VMAT
Source: Amethyst management