Which diagnostic procedure involves the largest exposure of bone marrow?

The examination of the pelvic girdle involves the largest exposure of bone marrow primarily due to the dense population of red bone marrow found in this area. The pelvic girdle contains significant quantities of hematopoietic tissue, which is responsible for the production of blood cells. Because radiation exposure is of particular concern for tissues that are highly proliferative, such as bone marrow, a diagnostic procedure that targets this region results in a greater dose compared to other anatomical areas.

When examining the skull, abdomen, or thorax, although those procedures may involve some radiation exposure, the quantity and activity of bone marrow in those regions is comparatively lower. Therefore, even though all these examinations utilize radiation, the pelvic girdle is specifically problematic due to the higher density of marrow and the associated risks of radiation exposure. Understanding this tissue distribution and its implications for radiation exposure helps frame the importance of minimizing exposure during imaging procedures.