moddicom: Package for handling DICOM RT files

Description Usage Arguments Details Value References

This function calculates the Normal Tissue Complication Probability according the Lyman/Kutcher/Burman model.

1	DR.Lyman(doses, TD50 = 45, gamma50 = 1.5, a = 1)

`doses`	Either a `dvhmatrix` class object or a vector with nominal doses
`TD50`	The value of dose that gives the 50% of probability of outcome
`gamma50`	The slope of dose/response curve at 50% of probability
`a`	Value for parallel-serial correlation in radiobiological response

This model is a reformulation of probit model by using other parameters than mean and standard deviation. In its original formulation the NTCP is given by the following equation:

NTCP=1/√{2π}\int_{-∞}^{t}exp(-x^2/2)dx

where:

v=\frac{V}{V_{ref}}

t=(D-TD_{50}(v))/(m*TD_{50}(v))

TD(v)=TD(1)*v-n

In previous equations V is the irradiated fraction volume and V_{ref} is the referenced volume for the given outcome, m is another way to describe the slope of dose-response curve (see following lines). In the moddicom implementation the parameters to be set in the model are TD_{50} and γ_{50}. The model has been coded by adapting the original formula using these parameters in this way:

t=(EUD-TD_{50})/(m*TD_{50})

with:

m=\frac{1}{γ_{50}√{2π}}

The relationship between Dose and Volume has been achieved by using the equivalent uniform dose as calculated by DVH.eud function.

A vector with NTCP(s) calculated according LKB model.

Burman C, Kutcher GJ, Emami B, Goitein M. Fitting of normal tissue tolerance data to an analytic function. Int J Radiat Oncol Biol Phys. 1991 May 15;21(1):123-35. PubMed PMID: 2032883.

kbolab/moddicom documentation built on Nov. 29, 2020, 9:11 p.m.