Overview of radiation dose to patients from medical X-ray examinations in Nigeria.

Abstract

Objectives: Medical Imaging accounts for the largest radiation exposure of population from artificial sources of radiation. The radiation dose rcceivedby patients from iedicail x-ray examinations in Nigeria has shown large variations within and among diagnostic centers for similar examinations. This could be traced to lack of imaging protocols and on avalability of local/national diagnostic reference, levels. Hence, the need to assess the trend of radiation doseto patients from radiological practice in Nigeria. Methocls:Entrance surface doses(ESDs) reported by, Nigerian authors for common x-ray examinations from 2000 - 2014 were extracted from articles published in peer reviewed journals, analyzed and compared with ifiternationally recommended Diagnostic Reference Levels (DkLs).

Results: Among x-ray examinations, skull accounted for 32% followed by chest (22%), lumbar spine (13%), abdomen (12%), pelvis (8%), extremitics(8%), thorax and cervical spine(5%). The range of mean ESDs reported for various projections of x-ray examination are chest (2.28 - 3.70 mGy); Abdomen (4.42 - 7.22 mGy); Skull (3.81 - 5.19 mGy); Pelvis (5.93 mGy); Lumbar spine (5.73 - 10.98 mGy); Thorax (0.96 - 1.85 mGy); Cervical spine (1.45 - 1.49mGy) and Extremitics (0.31 -0.49 mGy). In this study, it was found that the mean ESDs received by patients from chest, skull and pelvis ex'aminations were higher than the published DRLs for similar x-ray examinations.

Conclusion: The results of this study showed that to harmonize radiation protection of patients and improve radiological practice in Nigeria there is need for development of comprehensive national diagnostic reference levels.