IROC-Houstons Pediatric TBI Phantom Credentialing Program Andrea - - PowerPoint PPT Presentation

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Apr 14, 2023 128 likes •253 views

IROC-Houstons Pediatric TBI Phantom Credentialing Program Andrea Molineu, Hunter Mehrens, David Followill Denver Summer 2017 Meet Hansel and Gretel 2-fold purpose 10 yr old pediatric Credentialing CIRS phantom Lung dose

SLIDE 1

IROC-Houston’s Pediatric TBI Phantom Credentialing Program

Andrea Molineu, Hunter Mehrens, David Followill Denver Summer 2017

SLIDE 2

Meet Hansel and Gretel

10 yr old pediatric

CIRS phantom

No slices
No pre-drilled

holes

2-fold purpose
Credentialing
Lung dose

measurements

SLIDE 3

brain neck mediastinum umbilicus pelvis rt abdomen lt abdomen lung

SLIDE 4

TLD

13 TLD
Visible on CT
Loaded in

rods physicist can reload

SLIDE 5

Directions

Deliver 3 Gy to midline umbilicus
Use lung blocks as you would for patient

SLIDE 6

Irradiations

7 institutions 16 irradiations Variety of setups Variety of delivery With and without lung blocks

SLIDE 7

Position/Beam Direction

6 decubitus 4 sitting 1 supine 5 supine/prone 14 AP/PA 2 lateral

SLIDE 8

Plans/Lung Blocks

2 plans

(1 Eclipse, 1 Pinnacle)

8 blocked irradiations 8 non-blocked irradiations

SLIDE 9

Results

Area Average dose % of RX Umbilicus 297.5 ± 10.7 0.99 Neck 282.4 ± 21.8 0.94 Lung without blocks 324.1 ± 10.9 1.08 Lung with blocks 176 ± 101 0.59

SLIDE 10

Conclusions

Good agreement with RX point
Unblocked lungs receive ~8% higher than RX
Large variation in blocked lung dose
Some treatments give even blocked lung high

doses

SLIDE 11

Questions

Thanks!