DVH-class {RadOnc}

Class "DVH"

Description

A data structure containing Dose-Volume Histogram (DVH) data and associated parameters for a single structure

Objects from the Class

Objects can be created by calls of the form new("DVH", patient, structure.name, structure.volume, type, dose.max, dose.min, dose.mean, dose.median, dose.mode, dose.STD, conf.index, equiv.sphere, gradient, plan.sum, dose.rx, dose.fx, doses, dose.type, dose.units, volumes, volume.type, ...).

Slots

patient:

Name of the patient (e.g. "Jane Doe")

ID:

Additional patient identifier or medical record number (e.g. "123456789")

structure.name:

Name of the structure (e.g. "Stomach")

structure.volume:

Volume of the structure (in cubic centimeters)

type:

A character string specifying the DVH type (must be one of "cumulative" or "differential")

dose.max:

Maximum (point) dose contained within the structure

dose.min:

Minimum dose contained within the structure

dose.mean:

Mean dose to the structure

dose.median:

Median dose to the structure

dose.mode:

Modal dose to the structure

dose.STD:

Standard deviation of dose to the structure

conf.index:

Conformality index

equiv.sphere:

Equivalent sphere (diameter in centimeters)

gradient:

Dose gradient (in centimeters)

plan.sum:

Logical specifying whether or not data represents a plan sum (default is FALSE)

dose.rx:

Prescription dose (in units specified by dose.units)

dose.fx:

Fractional dose (in units specified by dose.units)

rx.isodose:

Isodose line (%) receiving prescription dose (default is 100%)

doses:

List of doses corresponding to "volumes"

dose.type:

A character string specifying the dose type (must be one of "relative" or "absolute")

dose.units:

A character string specifying the dose units (must be one of "cGy" or "Gy")

volumes:

List of volumes corresponding to "doses"

volume.type:

A character string specifying the volume type (must be one of "relative" or "absolute")

Methods

[

Extract dose or volume parameter(s) from DVH object. Only one parameter may be specified at a time. Parameter specification should be of the form ["<A><B><C>"]: <A> is equivalent to "V" or "D", representing a volume or dose, respectively; <B> usually denotes a numerical value specifying the dose or volume; and <C> represents the dose or volume units ("cGy", "Gy", "%", or "cc"). An example would be ["V20Gy"] which represents the volume of the structure receiving at least 20Gy dose. Dose ranges may also be specified, for instance ["V10-20Gy"] or ["V<20Gy"]. Specialized dosimetric keywords may also be used: "Dmax" (maximum dose), "Dmin" (minimum dose), "Dmean" (mean dose), "Dmedian" (median dose), "Dintegral" (estimated integral dose), "DRx" (prescription dose), and "volume" (total structure volume). If an improper parameter is specified however, NA results will be returned. See package documentation (vignette) for more details.

$

Extract a given parameter from a DVH object

$<-

Assign a value to a given parameter within a DVH object

c

Combine multiple DVH objects into a single list

lines

Plot DVH object (see link{lines})

max

Extract maximum dose from DVH object

mean

Extract mean dose from DVH object

min

Extract minimum dose from DVH object

names

Extract structure name from DVH object

names<-

Assign structure name to DVH object

plot

Plot DVH object

points

Plot DVH object (see link{points})

print

signature(x = "DVH"): Display summary of DVH object

range

signature(x = "DVH"): Extract dose range from DVH object

show

signature(x = "DVH"): Display summary of DVH object

sum

signature(x = "DVH"): Compute the total (summed) DVH from two or more DVH objects. Note that structures are assumed to be non-overlapping; any overlaps in structure volumes may generate inaccurate dose summation.

Author(s)

Reid F. Thompson ([e-mail])

See Also

DVH.list, read.DVH

Examples

# Description of structure/slots in class
showClass("DVH")