A baseline study of entrance dose and image quality for lumbar spine radiography in Calabar, Nigeria

PurposeTo obtain baseline data for implementing optimisation protocols in Nigeria, a study of the patient entrance surface doses (ESDs) and image quality for lumbar radiography in the two major hospitals in Calabar, Nigeria has been carried out.MethodA total of 74 patients cutting across the two hospitals were monitored during lumbar X-ray examination for entrance surface doses (ESDs) using Lithium Fluoride Thermoluminescent dosimeters (LiF-TLDs). Image quality of ensuing radiographs was studied by three experienced Radiologists using the European Commission (EC) criteria for lumbar radiography.ResultsMean patient entrance dose for the studied population was about 10.5 mGy (AP) and 23.1 mGy for the lateral projection. Third quartile ESD values suggest that up to 75% of the exposed population in lumbar radiography may be receiving doses above the EC reference level. Image quality scores against a reference image were marginally above average. There was no correlation between dose and image quality per radiograph. Results confirm the need for optimisation of procedure in the area.ConclusionProcedural changes are suggested in order to lower the patient doses and improve on the image quality of radiographs. These results are to be used as a reference for future review after the optimisation protocol is put in place.