[Assessment of radiation dose to patients in hysterosalpingography]

The optimization principle applied to the patient radioprotection, recently introduced in Italian legislation, requires a careful analysis of the working procedures and clinical protocols generally used in radiological practice, to avoid unnecessary exposures with no loss in diagnostic information. We carried out this analysis in hysterosalpingography, which is the radiological examination usually performed on fertile women to detect uterine and tubal conditions.

The dosimetric survey was carried out on 35 patients, 22 to 40 years old, to evaluate: a) entrance dose and dose x area product; b) doses to the most irradiated organs, that is ovaries and uterus; c) effective dose equivalent and effective dose. The doses were measured with LiF thermoluminescent dosimeters, while an ionization chamber enabled us to the calculate dose area product. Ovaries and uterus doses were calculated with a Monte Carlo program using skin entrance exposure data and some technical parameters of the examination.

The good agreement of the results obtained with both dosimetric methods demonstrated their equivalence in this specific case where the use of a clinical protocol, with no lateral projection, made the dosimeters lie always within the X-ray beam.

The mean dose was 4.5 mGy for the ovaries and 6.2 mGy for the uterus. Following the recommendations of the International Commission on Radiological Protection, both effective dose equivalent, with a mean value of 2.0 mSv, and effective dose, with a mean value of 1.95 mSv, were estimated. In conclusion, our results show that the patient dose can be reduced by limiting the use of fluoroscopy, using small size films and decreasing the number of exposures.