A software application to estimate exposure around 131I cancer and hyperthyroid patients

A Windows-based software application (IDOSE) has been developed to estimate time-dependent radiation exposure around patients who receive 131I-sodium iodide (NaI) for hyperthyroidism or thyroid cancer therapy. This application is based on radiation exposure associations which relate pharmacokinetically such factors as administered dose, distance from patient, directional projection and time. The software was tested by comparing its predictability with that obtained with a survey meter in-house as well as at neighbouring hospitals for a total of 74 patients who were administered 131I(NaI). The latter surveys were performed at the patient's surface, at 30 cm and at 100 cm, from 0.25 to 56 h post-administration for a total of 133 data points. Statistical testing showed r-coefficients of > 0.9 and paired t-test values of > 0.39 between the predicted and measured survey values for all distances surveyed. The versatility of IDOSE lies in its ability to predict radiation exposure to others who come into contact with the patient relative to projection, time and distance. The latter is based on patient- and literature-generated default values at administration for three distances: surface, 30 cm and 100 cm. Thereafter, IDOSE predicts exposures at the default distances as a function of time. User-generated survey values at administration are an input option. IDOSE will never take the place of an actual survey. Its potential lies with estimating such information at times when surveys are not possible. Hypothetical 131I(NaI) patients are followed to illustrate the multifaceted nature of IDOSE. This paper describes the development, implementation and efficacy of a user-friendly Windows-based software application for predicting radiation exposure around 131I(NaI) patients.