MR urography: Anatomical and quantitative information on congenital malformations in children.

BACKGROUND AND AIM: Magnetic resonance urography (MRU) is considered to be the next step in uroradiology. This technique combines superb anatomical images and functional information in a single test. In this article, we aim to present the topic of MRU in children and how it has been implemented in Northern Greece so far. The purpose of this study is to demonstrate the potential of MRU in clinical practice. We focus both on the anatomical and the quantitative information this technique can offer. MATERIALS AND METHODS: MRU was applied in 25 children (ages from 3 to 11 years) diagnosed with different types of congenital malformations. T1 and T2 images were obtained for all patients. Dynamic, contrast-enhanced data were processed and signal intensity versus time curves were created for all patients from regions of interest (ROIs) selected around the kidneys in order to yield quantitative information regarding the kidneys function. RESULTS: From the slopes of these curves we were able to evaluate which kidneys were functional and from the corticomedullary cross-over point to determine whether the renal system was obstructed or not. CONCLUSION: In all 25 cases MRU was sufficient, if not superior to other imaging modalities, to establish a complete diagnosis.

Unexpected dose to the daughter of a patient treated with iodine-131 for hyperthyroidism.

Patients treated with radioiodine for thyrotoxicosis and hyperthyroidism are a source of radiation exposure and represent a potential radiation hazard for the people in their environment. Doses to the relatives can be estimated from dose rates of the patient or measured with a proper dosimeter. Sensitive thermoluminescent dosimeters have been used to measure the doses absorbed by the family members of patients treated with iodine-131 ((131)I) for thyrotoxicosis. In the present case, a 12 year old daughter of a female patient, aged 41 years, treated with 592 MBq of (131)I, received a dose of 7.79 mSv during the first seven days. This value is well above the dose constraints proposed by the International Commission on Radiological Protection, i.e 1 mSv for children and fetuses and 3 mSv for carers. Obviously, the patient and her daughter didn't follow the given restrictions. That was unexpected for a 12 year old child who didn't need special care and was able to understand and follow certain instructions. It is the opinion of the authors that if there are children in the family of a hyperthyroid patient treated with (131)I, they should stay in another house for at least a week. If this is impossible for social reasons, hospitalization of the patient should be considered, although treatment of thyrotoxicosis is held in an out-patient basis.

[Proposals for the revision of radiation protection measures for doses up to 222 MBq iodine-131 for whole body scintiscan for the detection of metastatic lesions].

The goal of this study was to estimate the necessary period of time, required for radiation protection instructions to be followed by patients with differentiated thyroid carcinoma (DTC) after total thyroidectomy who are given iodine-131 ((131)I) for a whole body scintiscan (WBS) in relation to the instructions of the European Commission and the ICRP. In order to estimate and evaluate the dose received by the family members and the general public, we have studied 30 patients and were given a dose of 92-222 MBq of (131)I for a diagnostic WBS. The patients studied were four men with mean age+/-standard deviation (M+/-SD)=55+/-6 y and 26 women with: M+/-SD=47+/-14 y. Dose rate measurements were carried out at the Nuclear Medicine Department of the AHEPA University Hospital; 1 h after the patients had received the (131)I dose and 48 h later when they returned to the hospital for the WBS. The calculated doses received by the in-living relatives of the patients and by the general public, assuming that radiation protection measures were applied for 2d, ranged between 76-640 microSv and 22-171 microSv respectively. In conclusion, the results of this study, compared to the dose constraints suggested by the European Commission, indicate that the duration of radiation protection guidelines for patients receiving (131)I for diagnostic purposes could be reduced to only two days without any potential risk to family members or to members of the public. The case of children of the immediate family environment, aged less than 3 y, was not investigated in this study.