VDP Healthy Reference Calculator

129Xe VDP Healthy Reference Calculator

129Xe VDP Healthy Reference Calculator

Estimate age- and sex-specific healthy reference values, upper limit of normal, and z-scores for hyperpolarized 129Xe MRI ventilation defect percent across commonly used VDP quantification methods.

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Single Subject Calculator
Batch Excel Calculator
Required columns: SubjectID, Age, Sex. Optional: method-specific VDP columns such as TH60, Kmeans, AKmeans, LBmean, GLBmean, GLB99p, or one generic VDP column with the selected method.
Reference Curve and Results
Median VDP (%)
SD (%)
ULN (%)
z-score
Z-score interpretation
  • z = 0 → exactly average healthy value
  • z = 1.64 → approximately the 95th percentile (ULN threshold)
  • z > 2 → clearly abnormal
Observed VDP is used only to calculate the z-score. The plot displays the predicted median and ULN curves for the selected method and sex, with values marked at the selected age.
Reference and Citation
These calculations are based on age-dependent healthy reference equations derived from the multicenter 129Xe MRI Clinical Trials Consortium (XeCTC) ULN study for hyperpolarized 129Xe ventilation defect percent (VDP).
Please cite the ULN reference manuscript and acknowledge the XeCTC consortium if these reference equations are used in research, clinical reporting, presentations, software tools, or publications.