Keywords:
Paediatric, Genital / Reproductive system male, Digital radiography, Diagnostic procedure, Dosimetry, Experimental investigations, Quality assurance
Authors:
M. Jain1, A. CHOUGULE1, R. C. Sharma2, M. JOAN1, G. SINGH2, A. PRAJAPATI2; 1Jaipur, Rajasthan/IN, 2jaipur/IN
DOI:
10.26044/ecr2019/C-3060
Conclusion
The conventional chest examination was chosen for the study even though it is a relatively low dose examination but it is the most frequent pediatric radiography examination in all countries and,
due to very high frequency,
might produce a significant contribution to the collective effective dose.
The observed mean entrance surface dose (ESD) for chest radiography are higher than the National Radiological Protection Board (NRPB) DRL dose guidelines being the mean dose value instead of 75th percentile value as suggest for diagnostic reference level calculation and these dose level changes with different selections of the imaging parameters and imaging practices the observed dose levels are well within limit of 0.2mGy/projection as suggested by A.U.Sonawane,
et.al9 for chest x-ray examination of children aged between 10-15 years for Indian continent.
The variation in dose levels for chest radiography suggest that particular consideration is needed in the grouping of patients for pediatric radiographic examination because the size of children,
and hence the dose level,
significantly varies not only by age but also at a given age.
pediatric patients vary in size from premature babies (e.g.,
250 - 350 g) to obese adolescents (> 90 kg body weight) representing a factor of more than 300.
This is reflected in higher ESD dose values for children age between 10-15 year as compared to 5-10 and < 5 years Childs (Table1).
The gonadal dose values obtained from OSLD / Monte Carlo measurement are higher for neonates & children < 5 years in comparison to 5-10 and 10-15 age group children due to smaller size leads to the proximity of gonads from the radiation field.
(Table 2)
It is well known that different beam qualities or acquisition geometries in radiography can result in very different organ doses even when the entrance air kerma (EAK) / DAP values are the same.
It would be advantageous if the quantity is closely related to the real patient dose: organ doses and effective dose.
The mean dose to gonads of male children measured using OSLD and Monte Carlo simulation for Chest Radiography having a strong correlation (R2= 0.99) however the measured dose value by OSLD is higher than simulated gonadal dose value might account for angular dependency & low dose uncertainty of OSLD suggested by Al‐Senan at al10 in characterization of OSLD.
The observed gonadal dose values are for chest radiography of male child are very low11as compared to ESD value of Chest radiography account less than 0.4% of mean ESD and it has a very weak correlation (R2= -0.92).
The evaluation of patient doses enabling follow-up of the patient dose level when using similar equipment,
and also enabling comparisons with other equipment,
rooms or institutions for the same examination or procedure.
as sufficient data is not available on the pediatric doses.
Also,
the available data are sparse and scattered for various geographical regions.
The introduction of newer technologies with semiconductor-based detection has decreased the doses significantly.
Also,
the teaching and training of the technical staff are helping in lowering the exposure in pediatric imaging.