Extract DVH Data

How do I extract DVH data for a structure?

Below is Eclipse v11 script code that extracts DVH data for the first loaded PTV found for the loaded plan and structure set. The DVH data is written to a file in the user's temp directory called "dvh.csv".

{code:c#} public void Execute(ScriptContext context /, System.Windows.Window window/) { if (context.Patient == null || context.PlanSetup == null || context.PlanSetup.Dose == null || context.StructureSet == null) MessageBox.Show("Please load a patient, structure set, and a plan that has dose calculated!");

  // get reference to selected plan
  PlanSetup plan = context.PlanSetup;

  // linq query finds the first PTV structure
  Structure target = (from s in context.StructureSet.Structures where 
                      s.DicomType == "PTV" select s).FirstOrDefault();

  if (target == null) 
    throw new ApplicationException("Plan '"+plan.Id+"' has no PTV!");

  // build exported DVH filename, put it in the users temp directory
  string temp = System.Environment.GetEnvironmentVariable("TEMP");
  string dvhFilePath = temp + @"\dvh.csv";

  // export DVH for 'target' to 'dvhFilePath'
  exportDVH(plan, target, dvhFilePath);

  // 'Start' generated CSV file to launch Excel window
  System.Diagnostics.Process.Start(dvhFilePath);
  // Sleep for a few seconds to let Excel window start
  System.Threading.Thread.Sleep(TimeSpan.FromSeconds(3));
}
private void exportDVH(PlanSetup plan, Structure target, string fileName)
{
  // extract DVH data
  DVHData dvhData = plan.GetDVHCumulativeData(target,
                                DoseValuePresentation.Relative,
                                VolumePresentation.AbsoluteCm3,  0.1);

  if (dvhData == null)
    throw new ApplicationException("No DVH data for target '"+target.Id+"'.");

  // export DVH data as a CSV file
  using (System.IO.StreamWriter sw = 
                    new System.IO.StreamWriter(fileName, false, Encoding.ASCII))
  {
    // write the header, assume the first dvh point represents the others
    DVHPoint rep = dvhData.CurveData[0](0);
    sw.WriteLine(
      string.Format("Relative dose [{0}]({0}),Structure volume [{1}]({1}),", 
        rep.DoseValue.UnitAsString, rep.VolumeUnit)
    );
    // write each row of dose / volume data
    foreach (DVHPoint pt in dvhData.CurveData)
      sw.WriteLine(string.Format("{0:0.0},{1:0.00000}", 
                            pt.DoseValue.Dose, pt.Volume));
  }
}

{code:c#}