The Real Time Image Guided HDR Brachytherapy for Prostate Cancer. Treatment Planning Bashar Al-Qaisieh
Treatment Planning Objectives: Delivery of prescription dose to target volume and minimise dose to nearby normal tissues Bashar.Al-Qaisieh@leedsth.nhs.uk
Prostate HDR Treatment Planning Involves: • Pre-treatment QA: - equipment functionality and connectivity • Patient setup: - measurement of US probe and template position with respect to patient • Needle Insertion: - optimal position • Contouring: - position of applicators with respect to PTV and OAR • Dosimetry Planning: - needle reconstruction - source activation - optimisation Bashar.Al-Qaisieh@leedsth.nhs.uk
Patient Setup • Position of the US probe in the stepper unit • Position of template with respect to the US probe • Position of anatomy with respect to the template and US probe Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual”, “Live” & “Post” Operation Functions Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Image Capture- Set Base Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Image Capture Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Contouring • Option 1: - Contour Prostate, Urethra, Rectum - Utilise to produce a “virtual” plan - Utilise at later stages after needle insertion • Option 2: - Calculate volume estimate from H,W,L measurement (SJIO) Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Contouring- Option 1 Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Contouring- Option 2 HWL Volume Estimate 50 40 Live height (mm) 30 20 10 70 0 15 20 25 30 35 40 45 60 Virtual height (mm) 50 Live width (mm) 40 30 Regression line Recorded live width 20 95% 90% 85% 10 80% 0 25 30 35 40 45 50 55 Virtual width (mm) 80 70 60 Live length (mm) 50 40 30 Regression line Recorded live length 95% 20 90% 85% 10 80% 0 Bashar.Al-Qaisieh@leedsth.nhs.uk 20 25 30 35 40 45 50 55 60 Virtual length (mm)
“Virtual” Contouring- Option 2 Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion • Option 1: - Forward - Manual and Geometric - SJIO • Option 2: - Inverse - HIPO Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion-Option 1:Forward Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion-Option 1:Forward SJIO • Reference transverse plane for peripheral needles • Base and Apex for middle needles Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion-Option 1:Forward SJIO Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion-Option 1:Forward SJIO • All needles inserted to same depth of at least 1.0cm beyond the base to account for needle dead end for metal needle 1 cm Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion-Option 2:HIPO Bashar.Al-Qaisieh@leedsth.nhs.uk
“Virtual” Needle Insertion-Option 2:HIPO Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Image Capture • All needles pushed to at least 1.0 cm deep from the base. • Needles Locked to the template. • Take final base measurement Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Needle Tip Tracking • All needle tips are updated at the same depth (base). Convert needles from “V” to “L” Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Needle Tip Tracking Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Image Capture Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Contouring Guidance • Update “Virtual” contours to match “Live” image set • Prostate dimension pre needle insertion • Record of needle position with respect to the prostate as a surrogate Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Contouring and PTV Margins Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Contouring Bashar.Al-Qaisieh@leedsth.nhs.uk
Needles Free Length measurement and “Live” Tracking Measured TPS Recorded Bashar.Al-Qaisieh@leedsth.nhs.uk
Needles “Live” Tracking Bashar.Al-Qaisieh@leedsth.nhs.uk
“Live” Source Activation Bashar.Al-Qaisieh@leedsth.nhs.uk
Planning Aims and Optimisation Options • Prostate: – 15Gy=100% isodose – V100%>95% – V150%<45% – V200%<15% – D90>100% • PTV: – V100%>95% • Rectum: – D2cc<11.8Gy – V100%=0.0cc • Urethra: – D10%<17.5Gy – D0.1cc<17.5Gy Morton et al 2009, GEC-ESTRO 2013 Bashar.Al-Qaisieh@leedsth.nhs.uk
Inverse Optimisation-DVHO Bashar.Al-Qaisieh@leedsth.nhs.uk
TG 43 Dose Calculation 10 9 8 7 r Depth Dose 6 5 4 3 2 1 0 0.5 1.0 1.5 2.0 2.5 3.0 Distance (cm) Bashar.Al-Qaisieh@leedsth.nhs.uk
Inverse Optimisation-DVHO Bashar.Al-Qaisieh@leedsth.nhs.uk
DVH output Bashar.Al-Qaisieh@leedsth.nhs.uk
Good Job…well done!!! • Oncologist check • Approve plan • Print and transfer to treatment machine • Handover to physics to independent check • Handover to radiographers • Have a cup of coffee!! Bashar.Al-Qaisieh@leedsth.nhs.uk
Timing According to Individual Planners Data from 20 implants- 2012 Time from probe in to patient Needle Needle Planner (no cases) treated insertion reconstruction Planning A (4) 02:22 00:24 00:14 00:10 B (4) 02:54 00:28 00:29 00:13 C (2) 02:54 00:38 00:16 00:24 D (7) 02:53 00:25 00:16 00:15 E (3) 02:52 00:36 00:21 00:14 Bashar.Al-Qaisieh@leedsth.nhs.uk
Thank You Bashar.Al-Qaisieh@leedsth.nhs.uk
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