Bone marrow and peripheral blood cells toxicity of a single 2.0 gy cobalt60 ionizing radiation: an animal model

BACKGROUND: Bone marrow is extremely vulnerable to damage caused by radiation therapy. Hence, bone marrow suppression is an important side effect of radiotherapy. Effective use of radiotherapy is therefore compromised by radiation-related injuries. MATERIAL AND METHODS: Six Guinea-pigs were recruited for the study of which three were subjected to total body irradiation with Co60 while the other three served as controls. Bone marrow and peripheral blood samples were collected before and at days 9, 14 and 21, post irradiation. Manual and automated counts were performed for bone marrow nucleated cells and peripheral blood cells respectively. RESULTS: Declining bone marrow cellularity was evident immediately post irradiation. Mean ± SD of marrow cell counted per mm3 were 121,924±281, 87,603±772, 121,367±375 and 122,750±1000 pre-irradiation and days 9, 14 and 21, postirradiation (p-values 0.10, 0.27 and 0.29 respectively). Significant drops in counts were noticed on day 9 post-irradiation for all red cell parameters (p-values <0.05), for Total White Blood Cell Count and Neutrophil count (p-values <0.05) and also on days 14 and 21 for Lymphocytes (p-values <0.05) and on day 21 for Eosinophil/Basophil/Monocytes (p-value <0.05). A significant drop in platelets counts was also noticed on day 9 (p-value <0.05) which significantly increased above pre-irradiation value on day 21. CONCLUSION: Total body irrradiation with Co60 significantly affects the bone marrow with maximum reductions in marrow nucleated cells and peripheral blood cells counts on day 9 post irradiation

Occupational hazards among medical radiation workers

Objectives: The objective of the study was to determine the prevalence of occupational hazards among medical radiation workers in Northern Nigeria and to assess the adequacy of existing occupational safety measures in the region. Materials and Methods: A prospective cross-sectional study of 139 medical radiation workers in six tertiary health-care institutions in northern Nigeria. Structured questionnaires were used to obtain vital information about the occurrence of occupational hazards, prevention and control measures. Data were analyzed using descriptive and inferential statistics using the computer software SPSS. Results: Out of 159 questionnaires distributed 139 were retrieved giving a response rate 87.4%. Stress, direct contact with bodily fluids, and contrast media splashes were the three most prevalent hazards reported by 121 (87.1%), 78 (56.1%), and 72 (51.8%), respectively. Conclusion: Medical radiation workers in Northern Nigeria face a wide range of occupational hazards, and therefore concerted efforts must be channeled toward mitigating these hazards

Radiation Dose in Paediatric Computed Tomography: Risks and Benefits

Computed tomography (CT) is a powerful tool for the accurate and effective diagnosis and treatment of a variety of conditions because it allows high-resolution three-dimensional images to be acquired very quickly. However as the number of CT procedures performed globally have continued to increase; with growing concerns about patient protection. Currently; no system is in place to track patient doses and the lifetime cumulative dose from medical sources. The widespread use of CT even in developing countries has raised questions regarding the possible threat to public health especially in children. The best available risk estimates suggest that paediatric CT will result in significantly increased lifetime radiation risk over adult CT. Studies have shown that lower milliampere-second (mAs) settings can be used for children without significant loss of information. Although the risk-benefit balance is still strongly tilted toward benefit; there is still need for caution. Furthermore since the frequency of paediatric CT examinations is rapidly increasing; and estimates suggest that quantitative lifetime radiation risks for children are not negligible; efforts should be made toward more active reduction of CT exposure settings in paediatric patients. This article hopes to address this concerns and draw attention to the fact that children are not 'small adults ' and should therefore be treated differently

Assessment of the impact of background gamma radiation on reproductive defects in two major IGBO towns of Nigeria

Late biological effects of ionizing radiation on humans result in induction of cancers and various forms of genetic defects. A preliminary survey of hospital based data in Enugu and Owerri in the South Eastern States of Nigeria were carried out to ascertain possible relationship between our observed data on background radiation levels and reproductive abnormalities in these areas. The incidence of reproductive defects seems to correlate more with life style and socio-economic status than with background radiation dose rates

Assessment of chest radiographs for quality assurance and radiation protection

A retrospective study of 1000 chest radiographs randomly selected from various government and private owned hospitals in the southern part of Nigeria covering a period of twenty years was carried out. Accuracy in patient positioning; beam collimation and identification of radiographs were assessed as indicators for quality assurance and radiation protection. The result showed that for male 59 were rotated and 41 were not. For the female; 60 were rotated while 39 were not. 95.30 radiographs were inadequately collimated; and 69.30 were properly identified. This suggests poor quality and exposure of patients to unnecessary radiation though more attention was paid to identification of radiographs

Occupational radiation monitoring and quality assurance in hospital X-ray departments

Quality assurance is essential to any programme of diagnostic radiology; to prevent undue exposure of x-ray personnel and patients to radiation. This paper reports observations from a survey of some hospital x-ray facilities in Accra and Kumasi in Ghana; to find out about steps taken by x-ray workers to ensure quality control and administration in diagnostic radiology. The grid point method has been used to do a detailed study of scatter radiation levels of two x-ray departments in Accra. The iso-dose rate contours have been analysed; and results show the importance of good design of x-ray rooms and provision of protective structures