/// Calculates the RTOG conformity index as isodose volume irradiated at reference dose (Body contour volume irradiated)
/// divided by the target volume. Does not necessarily mean the volumes are coincident!
/// </summary>
/// <param name="s">the target structure</param>
/// <param name="pi">the planning item containing the dose</param>
/// <param name="referenceDose">the reference isodose (eg. prescription dose)</param>
/// <returns>RTOG conformity index</returns>
public static double GetCI_RTOG(ESAPIX.Facade.API.Structure s, ESAPIX.Facade.API.PlanningItem pi, DoseValue referenceDose)
{
var external = pi.GetStructureSet()?.Structures.FirstOrDefault(st => st.DicomType == DICOMType.EXTERNAL);
if (external == null)
{
return(double.NaN);
}
var prescription_volIsodose = pi.GetVolumeAtDose(external, referenceDose, VolumePresentation.AbsoluteCm3);
var target_vol = s.Volume;
return(prescription_volIsodose / target_vol);
}
/// <summary>
/// Converts the dose to the system units. It cannot convert from % to abs dose. Will return NaN if asked
/// </summary>
/// <param name="dv">the dose value to be converted</param>
/// <param name="unit">the unit desired for the returned dose</param>
/// <returns>the dose in the desired units</returns>
public static DoseValue ConvertToSystemUnits(this DoseValue dv, ESAPIX.Facade.API.PlanningItem pi)
{
var newDv = new DoseValue(dv.Dose, dv.Unit);
if (dv.GetPresentation() != DoseValuePresentation.Relative)
{
// Need to convert to system units first (ugh!)
var oldPresentation = pi.DoseValuePresentation;
pi.DoseValuePresentation = DoseValuePresentation.Absolute;
if (pi?.Dose != null)
{
var systemUnits = pi.Dose.DoseMax3D.Unit;
pi.DoseValuePresentation = oldPresentation;
//Thanks ESAPIX!
newDv = dv.ConvertUnits(systemUnits);
}
else
{
throw new Exception("Cannot determine system units for dose. Plan dose is null");
}
}
return(newDv);
}
