Achieving dose reduction in lumbar spine radiography

Conventional lumbar spine examinations are performed by placing the patient in the supine position. The alternative prone position is less commonly used. In this study, researchers measured entrance skin exposure for both supine and prone positioning techniques and the radiation dose to the eyes, thyroid, ovaries, testes and bone marrow. Compared with the AP projection, the PA projection produced a moderately higher bone marrow dose (28%), but resulted in a slightly reduced dose (17%) to the thyroid and greatly reduced doses (200+%) to the eyes, ovaries, uterus and testes. The PA projection also produced an ESE 52% lower than the AP projection. Results suggest an advantage to using prone positioning for lumbar spine examinations.