An experimental study was carried out to determine the radiation doses received by the brain, thyroid glands and the genital organs (i.e. ovaries testicles) of the babies in the Neonatal Intensive Care Unit during chest radiography. A Perspex block phantom of similar size to the neonate was exposed to radiation using the actual average exposure parameters that applied normally in the NICU. The doses were measured using thermo-luminance lithium fluoride dosimeter chips. The entrance and exit doses were then measured for the brain, thyroid and gonads organs. The measurement was obtained with and without shielding. The results of our study showed that infants did not receive what might be considered excessive radiation from diagnostic modalities. Entrance Skin Dose was found to be below the European Committee reference dose of 80 mGy for mobile chest radiographs. Applying the radiation protection shield such as 0.5 mm lead rubber sheet is of great value in reducing the radiation doses to the brain cells and the gonadal organs.

Radiography is one of the important new mean of investigation in modern medicine. Diagnostic radiology is increasingly used in the assessment and treatment of neonates requiring intensive care. Therefore, in a department such as the Neonatal Intensive care Unit, it becomes of a great importance as it gives the physician an easy and accurate way of examining neonate. The commonest clinical indications of chest radiography on NICU include; respiratory distress syndrome, acquired pneumonia pre/ post-delivery and pneumothorax which is a complication of RDS or aspiration ventilation in the newborn. Consequently there are a lot of risks in using x-rays on the human body cells. These risks can be divided into somatic and genetic effects. The somatic effects include infertility, cancer and cataracts. The genetic effects show abnormal features in the infants after the excessive exposure of the pregnant mother to radiations. However in an NICU, where the incubator plays the role of the mother womb, it becomes impossible to avoid radiation that is because the neonate is got to have an x-ray taken at least to justify his /her stay in the unit, where the premature newly born sick children infants are kept to be looked after.

Radiographic examinations of neonates are particularly critical because of delayed radiogenic cancers as a consequence of a relative longer life expectancy. The small size of neonates, especially of premature infants, places all organs within the useful beam, resulting in a higher effective dose per radiograph than may be the case with older children and adults. Therefore, radiation doses for neonatal X-ray examination should be kept to a minimum. It is also important to ensure that radiation doses from repeated radiographic examinations carried out frequently in the same room of the NICU should be kept at a minimum. The aim of this work was to determine the radiation doses received by the infants from radiographic exposure in order to find the dose received by brain, thyroids and gonadal organs  during an antero-posterior chest x-ray with and without shielding.

With Regards,
Sara Giselle
Associate Managing Editor
Journal of Medical Physics and Applied Sciences