![Page 1: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/1.jpg)
Integrating dose spatial distribution into radiotoxicity
calculation
Ming Zhang
Dept. of Bioinformatics & Computational BiologyUniversity of Texas M.D. Anderson Cancer Center
![Page 2: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/2.jpg)
Radiotoxicity
![Page 3: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/3.jpg)
Dose volume histogram
Toxicity measured by dose volume (surface) histogram
volu
me
dose (Gy)
dose map DVH
![Page 4: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/4.jpg)
Dose spatial distribution
Dose levels and spatial distribution both affect toxicity
![Page 5: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/5.jpg)
Maximum clusters
2 / 42 ( / )
1( )
1b D D a
p De
probability that the voxel is damaged
dose received at a voxel
local damage function:
![Page 6: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/6.jpg)
Cluster of damaged voxels
Clusters: connected components of damaged voxels
cluster size =1, 1, 1, 1, 1
cluster size =1, 3
maximum cluster
![Page 7: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/7.jpg)
Connectivity
1-connectivity
2-connectivity
![Page 8: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/8.jpg)
Maximum clusters
local damage probability
maximum clusterlocation
maximum cluster size
2648.91
dose map
![Page 9: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/9.jpg)
maximumclustersrendering
![Page 10: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/10.jpg)
Example
![Page 11: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/11.jpg)
DSH(absolute area)
![Page 12: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/12.jpg)
DSH(relative area)
![Page 13: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/13.jpg)
differenceof maximumclusters
![Page 14: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/14.jpg)
Discussions
Maximum clusters describe radiotoxicity by
Incorporating dose spatial distribution into cluster calculation
Working with all dose levels simultaneously
Providing a visualization tool to select treatment plans (location and size of maximum cluster)
![Page 15: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/15.jpg)
Discussions
Local damage function
sigmoidal shape: analytical, piecewise
parameters (patient/organ specific)
Computational complexity
number of iterations in simulation
all possible parameter combinations
![Page 16: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/16.jpg)
Dose component histogram
![Page 17: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/17.jpg)
Dose component histogram
For each dose level d
DVH: sum of all voxels receiving dose d or more
DCH: largest component of organ region receiving dose d or more
![Page 18: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/18.jpg)
Cluster/component connectivity
• Local connectivity (immediate neighborhood)
– 1-connectivity
– 2-connectivity
– n-connectivity
• Regional connectivity (extended neighborhood)
![Page 19: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/19.jpg)
Regional connectivity
![Page 20: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/20.jpg)
Conclusions
Dose spatial distribution should be integrated into radiotoxicity calculation
Connectivity determines cluster/component formation
Maximum cluster
works with all dose levels simultaneously
provides size and location of MC (rendering)
Dose component histogram (DCH)
Incorporates spatial distribution into DVH
![Page 21: Integrating dose spatial distribution into radiotoxicity calculation](https://reader035.vdocuments.us/reader035/viewer/2022062315/568159fa550346895dc7461a/html5/thumbnails/21.jpg)
Collaborators:
Howard Thames, Ph.D. (MDACC)
Susan Tucker, Ph.D. (MDACC)
Radhe Mohan, Ph.D. (MDACC)
Lei Dong, Ph.D. (MDACC)
Xiaodong Zhang, Ph.D. (MDACC)
Ronald Goldman, Ph.D. (Rice)
Falai Chen, Ph.D. (USTC, China)
Ming Zhang, Ph.D.Department of Bioinformatics &
Computational BiologyUT M.D. Anderson Cancer [email protected]