مجله دانشکده پزشکی اصفهان (Jul 2011)
The Average of Cumulative Radiation Dose in Neonates in the Neonatal Surgery Ward Due to Diagnostic and Therapeutic Radiologic Procedures During the Admission Period
Abstract
Background: The carcinogenic effect of radiation is directly related to the exposure rate and the risk is even more in infants. The scope of the present study is to evaluate of the average of cumulative radiation dose in neonates in the neonatal surgery ward due to diagnostic and therapeutic radiologic procedures during the admission period, in Alzahra hospital of Isfahan, Iran. Methods: This investigation was a descriptive study on 168 neonates. It was done in neonatal surgery ward during last 9 months of 2009 in Alzahra hospital of Isfahan, Iran. The patients were selected randomly and with no attention to age, sex, diagnose and admision time. Thermo luminescent dosimeters (TLD GR200), were used for dosimetry and each chips was putted in a plastic envelope on the neonate sternum during the admission period. The cumulative absorbed dose by each patient was stored during the admission by TLD and followed by reading by TLD reader. For using of TLDs, they were calibrated and two calibration factors (individual and batch) were performed in radiotherapy section of Seyed Al-shohada hospital of Isfahan, Iran. After checking the accuracy of calibration, the absorbed dose by each patient was achieved by using of calibration factors. Finding: The average of admission time for each patient was 7.64 days and the average of cumulative absorbed dose was 3.13 Millisievert (mSv) during this time. The maximum absorbed dose in one patient was 42.83 mSv. The average number of conventional radiography for each patient was 2.77. The average of conventional radiography and cumulative absorbed dose in patient with no examination or just simple x-ray examinations was 2.58 and 0.863 mSv, respectively. Chest x-ray examination was the most examination used here (338 person). The average dose for each chest x-ray examination was 0.313 mSv. The average of cumulative absorbed dose among patients with fluoroscopic examination was about 12.6 mSv. The cumulative absorbed dose in 19 patients was more than 10 mSv. Conclusion: The average of cumulative absorbed dose was not more than the dose limit according to reference levels, but in comparison with other medical centers in the world is very high. Therefore, it is necessary to pay more attention to reduce radiological imaging procedures, particularly about fluoroscopic procedures.
