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Purpose: This paper illustrates the annual trends in medical radiation exposure due to conventional radiography (CR), computed tomography (CT) and nuclear medicine (NM) procedures of the Emilia-Romagna population from 2001 to 2006., Materials and Methods: We gathered information about the type, number and mean doses of CR, CT, and NM examinations performed in 17 hospitals of the Emilia-Romagna region. In particular, numerical values of the following dosimetric parameters were requested: entrance skin dose for CR, CT dose index and dose-length product for CT and activity administered for NM. Lastly, the annual collective dose S and annual average per-caput dose were calculated., Results: The 13 diagnostic imaging procedures that were the greatest contributors to the Emilia-Romagna population dose between 2001 and 2006 were identified and, for the year 2006, their percentage contribution to total procedures and population dose are indicated. CR, CT and NM accounted for 12%, 78% and 10% of the dose, and 83%, 15% and 2% of total procedures, respectively. The annual trends of S and average per capita dose are shown, and the theory underlying the use of these parameters is briefly discussed., Conclusions: This type of study relies heavily on the analysis of field data and as such, the growing attention paid in recent years to procedure optimisation should continue, and expand even for the justification of the procedures themselves as justification has a significant impact on the reduction of S and per-caput doses.

Purpose: The Italian Decree of Law 187/2000 provides for many fulfilments relevant to justification and optimisation of medical exposures that can complicate the daily work of radiology departments if considered as mere legal requirements. On the contrary, this law should be regarded as a good opportunity to analyse and optimise working practices. To this end, the Emilia- Romagna Region carried out an initial assessment of medical exposures to its population in 2001 followed by a second survey taking into account new dosimetric evaluations. This paper illustrates the results of this second survey and analyses the most significant parameters in comparison with similar studies reported in the literature., Materials and Methods: We first determined the examinations to be considered: 12 easily identifiable examinations divided into macroaggregates were selected for conventional radiography and computed tomography (CT). Hospitals of the Emilia-Romagna Region were directly asked to provide the number of examinations performed subdivided by type and grouped by nomenclature code, some technical parameters related to both examination protocol and equipment and the value of dose quantities as measured by local medical physicists., Results: Study of distribution of the entrance skin dose for different examinations in single hospitals showed no systematic differences in kilovoltage settings versus dose whereas the number of examinations tended to be inversely proportional to dose. These trends could be explained by the fact that in hospitals where many examinations of the same type are performed, operators, equipment and procedures are well integrated, leading to a level of specialisation that allows efficient interaction in order to deliver an "optimal dose". Analysis of the "entrance skin dosemax"/"entrance skin dosemin" ratios for various projections and comparison with literature data seem to show that a "scale factor" has a fundamental role in the variability of entrance skin dose values amongst hospitals and that "chest" examinations are the most critical, with the greatest differences in entrance skin doses., Conclusions: The evaluations performed in this study show that this type of analysis heavily relies not only on the cooperation of all professionals responsible for patient radiation protection but also on the experience gained during previous surveys because data collection is a very critical process that can invalidate, if not carefully performed, all subsequent processing.

An assessment of the electromagnetic fields emitted from short and ultrashort wave diathermy sources and from magneto therapy operating at a frequency of 50 Hz was made to evaluate the occupational exposure to the operators. Operators were exposed to electromagnetic fields which rarely exceed the recommended limits of International Commission on Non-Ionizing Radiation Protection (ICNIRP) and American Conference of Governmental Industrial Hygienists (ACGIH). Only a measurement of electromagnetic fields near short wave diathermy equipment operating at a frequency of 27.12 MHz exposed operators to levels above those recommended by ICNIRP at a distance of 1 metre. Magnetic fields of magneto therapy exceeded residential exposition of 1 microtesla, at a distance of 4 metres.

The dosimetric values measured on digital dental examinations (panoramic radiography and cephalography) were compared with those obtained with screen-film combinations. The X-ray dose was measured at the critical organs (lens, thyroid, cervical cord) on an anthropomorphic phantom, using thermoluminescence dosimeters and an ionization chamber: the radiographic unit was set at the same exposure values used for standard human studies in adults and children. The mean thyroid dose for screen-film panoramic radiographs was 0.037 mGy in the child and 0.053 in the adult; the lens and the cord doses were 0.009-0.012 mGy and 0.096-0.135 mGy, respectively. Digital panoramic radiography gave the thyroid a dose of 0.013 mGy in the child and 0.016 mGy in the adult: such a marked dose reduction was observed for the lens and the cervical cord too (0.0044-0.0052 mGy and 0.035-0.042 mGy, respectively). With conventional film cephalography the thyroid was given a mean dose of 0.042-0.072 mGy according to age and to patient's size; the lens received higher doses (0.420-0.720 mGy). These values were markedly reduced with the digital technique; 0.032-0.034 mGy to the thyroid gland and 0.320-0.340 mGy to the lens; spinal cord doses became negligible with digital exposures (0.009-0.010 mGy). The overall analysis of dosimetric values demonstrated a mean dose reduction averaging 40-60% with respect to standard film exposure. This difference is more apparent in the adult, since the linear dose-response pattern of the digital system allows good images to be acquired in "thicker" people without markedly increasing exposure values.

The effective dose (ED) and the organ dose given with Computer Tomography (CT) scanners can be determined by means of a computing method suggested by the English National Radiological Protection Board (NRPB). This method uses the integral air-dose profile as input. Due to the non-rectangular shape of the CT profiles, a Computer Tomography Dose Index (CTDI) has been defined, as the integral dose profile divided by nominal slice thickness. The experimental determination of the CTDI can be carried out with thermoluminescent dosimeters. However, the measurement can be simplified by using a cylindrical ion chamber. This paper reports the calibration of a PMO5 ion chamber (5 cm3 in volume and 5 cm in length) in terms of sensitivity value (4.45 pC mGy-1 mm-1). CTDI measurements by means of a PMO5 ion chamber were used to determine the effective doses and lung doses for the CT scanners used at the Institute of Radiology of the Catholic University in Rome. The dose levels thus obtained are in agreement with other national and international data. Moreover, the method allows the differences in the doses absorbed by the patients submitted to CT with different technical approaches to be calculated.

The authors examine 62 cases of curietherapy in the deep vagina on 21 cases of utero-vaginal applications and make a comparison between two dosimetric methods used to measure the dose to the rectum and to the bladder: the direct measure by the Siemens Gammameter dosimeter and the Chassagne-Horiot method. Very large differences were found between the doses evaluated by the two methods. The values with the direct measure were often found to be higher than the calculated ones. When the measurements were done by different doctors, the result was almost the same.

The effects produced as a consequence of the Chernobyl nuclear reactor accident in the population of Como are assessed on the basis of the measurements taken in the environment and on the food. Exposure measurements produced by external radiation and the activities of the different radionuclides introduced into the body, by ingestion and inhalation, made it possible to obtain an estimate of the dose equivalent and its somatic and genetic effects on the population. The results show that such effects may produce 0.5-2 cases of malignant tumour in the next 25 years and 0.2-1 case of genetic damage in the next 60 years and are therefore statistically insignificant.

The authors present a preliminary dosimetry study of 10 MV X-rays for irradiation technique with only one anterior mantle-field. The results of the studied beam for SSD = 120 cm are: 40 X 40 cm2 fields, build-up at 2.5 cm, penumbra (85% divided by 15%) variable between 8 divided by 9 mm, 50% of the dose at depth of 18 cm, homogeneity +/- 4%. These dosimetry results are suitable for beginning the clinical research.

We make use of an individualized moving strip technique (MST) for ovarian cancer radiotherapy. On the pelvis, strip fields have smaller width than in usual MST proposed by Dembo and Delclos, and different heights. Femoral heads are spared without needing lead shields. Thus our technique can be useful for patients previously treated by heavy chemotherapy. Dosimetric checks by computer, TLD, and film dosimetry, show a fair dose homogeneity inside target volume.

The X-ray absorption meter (Diagnostic energy between 20-60 Kev) of common place-glass has been studied. The possibility of replacing lead glass with a reinforced type, also very cheap, has been examined.

At the Casaccia Nuclear Centre the personnel occupationally exposed to a risk of internal contamination from radioactive substances is controlled by means of periodic radiotoxicological analyses. About 30,000 analyses of natural uranium, enriched uranium, thorium, gamma emetters, plutonium, americium, etc. in urine have been carried out since 1962. In the case of accidental acute radiocontamination by inhalation, wound and ingestion, special control on urine, blood, feces, nasal swabs, etc. must be schedules. The results can be very useful to the medical staff in order to take the most suitable therapeutical measures or to calculate the body burden.

The release into environment of liquid radioactive wastes coming from the metabolic therapy department of the Spedali Civili in Brescia was monitored during six months, with a rate of release of about 20 divided by 50 mCi of 131I every 30 divided by 40 days. Samples of 10 liters of liquid, taken from sewers downstream from the release point during a release operation, was percolated on 50 cm3 of ionic exchange resin in order to achieve a suitable counting rate with a Ge(Li) crystal spectrometer, connected to a 2048 channel analyzer. From these measurements a dilution curve along the sewers course was obtained, allowing one to know, for a given radioiodine concentration at the release point, concentration at every point downstream. In this way, by means of a simple linear compartmental model, it is possible to calculate the average individual dose taken by individuals who are living in the region (250.000 inhabitants) in one year of release operations. In our case we considered, as critical pathways to man, cow milk, meat, cereals and fruits: we obtained for thyroid, which in the case of radioiodine is the critical organ, an individual annual dose of 5,41 x 10(-4) mrem, while for total body we obtained 9,49 x 10(-7) mrem.