Evaluation of Effective Dose in Hysterosalpingography

The high dose acquired during hysterosalpingography and the young age of the women who undergo this examination call for an accurate dosimetric analysis and the setting up of optimisation procedures The results are presented of a survey of doses given to patients during hysterosalpingography. A transmission ionisation chamber and thermoluminescence dosemeters (Tl.Ds) were used to evaluate the dose-area product and the entrance dose, respectively. The first dosimetric method enabled an insight to he gained into the relative contribution of the different radiographic projections and of fluoroscopy. The mean entrance dose values for the complete examination evaluated from ionisation chamber measurements or measured by TLDs were 23.9 ± 3.4 mGy and 25.2 ± 3.8 mGy respectively, including backscattering. Ovary and uterus doses were evaluated from entrance skin dose by a Monte Carlo program and compared with direct measurements of the uterus dose obtained by positioning the Tl.Ds in the plastic cup of the microinjector, used to introduce the contrast medium. The possibility of employing this last method for individual dose monitoring was investigated. Effective dose evaluation was carried out on the basis of the dose-area product measurements using the conversion coefficients published by the National Radiological Protection Board (NRPB). Finally, it was found that a proper choice of film size and the exclusion of the direct antero-posterior (AP) projection can significantly reduce the dose to the patient.